JPH07223372A - Information recording thin film and information recording medium - Google Patents

Abstract

(57) [Summary] [Purpose] It enables rewriting or super-resolution reading many times more than before while maintaining good recording and reproducing characteristics. [Structure] An Sb-Te-Ge-based or Sb-Te-In-based phase-change recording film 3 or a super-resolution readout thin film is provided with C
r, and Ag, Ba, Co, Ni, Pt, Si, S
r, Au, Cd, Cu, Li, Mo, Mn, Zn, A
1, Fe, Pb, Na, Cs, Ga, Pd, Bi, S
At least one element X or B selected from n, Ti, V, In and lanthanoid elements is added. A component 3b having a higher melting point than the phase change component 3a is deposited in the recording film 3 or in the super-resolution reading thin film to prevent flow / segregation of the film during recording / erasing and super-resolution reading.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information recording thin film, a method of manufacturing the same, and an information recording medium.
An information recording thin film capable of recording / reproducing information obtained by M-modulation, digital data such as computer data, facsimile signals and digital audio signals in real time by an energy beam such as a laser beam or an electron beam, or The present invention relates to a super-resolution reading thin film, a manufacturing method thereof, and an information recording medium using the information recording thin film or the super-resolution reading thin film.

[0002]

2. Description of the Related Art Various principles of recording information on a thin film (recording film) by irradiating laser light are known. Among them, lasers such as phase transition (also called phase change) of film material and photodarkening are known. The one utilizing the change in atomic arrangement due to irradiation of light has an advantage that an information recording medium having a double-sided disc structure can be obtained by directly laminating two disc members, since the thin film is hardly deformed. Also, GeS
A bTe-based or InSbTe-based recording film has an advantage that information can be rewritten.

However, with this type of recording film, if rewriting is performed a number of times more than 10 ⁵ times in pit position recording and 10 ⁴ times in pit edge recording,
Since the rewriting property is deteriorated by the flow of the recording film, a method for preventing the flow of the recording film has been studied. The flow of the recording film is caused by the laser irradiation during recording, which causes the recording film to flow, and the recording film is gradually pushed due to the deformation of the protective layer and the intermediate layer due to thermal expansion.

For example, Japanese Patent Application Laid-Open No. 4-228127 discloses a method of preventing flow by forming microcells of a recording film, and see T. Ohta et al. "Optical Data Str
age "'89 Proc. SPIE, 1078, 27 (1989) prevents the flow of the recording film by making the recording film thinner to lower the heat capacity and increasing the influence of the adhesive force between adjacent layers. A method of doing so is disclosed.

An analog information signal obtained by FM-modulating a video signal, an audio signal, etc., and an optical disc on which digital information signals such as computer data, a facsimile signal, a digital audio signal, etc. are transferred as unevenness on a substrate surface, a laser beam, an electron beam. In an optical disc having a recording thin film for recording signals and data in real time by a recording beam such as a recording beam, the signal reproduction resolution is almost equal to the wavelength λ of the light source of the reproduction optical system and the numerical aperture of the objective lens. It is determined by NA, and the recording mark period 2NA / λ is the read limit.

As a method for increasing the recording density, a method of reproducing data recorded with concavities and convexities using a medium whose reflectance changes by a phase change is described in Japanese Patent Laid-Open No. 3-292632, and A medium having a fused mask layer for high density reproduction of data recorded on a phase change recording film is described in Japanese Patent Laid-Open No. 5-73961.

In the present specification, not only the phase change between crystal and amorphous but also melting (change to liquid phase) and recrystallization,
The term "phase change" is used to include a crystalline state-to-crystalline state phase change.

[0008]

When any of the conventional recording films is used as a rewritable phase transition type recording film, the number of rewritable times is not sufficient, and the crystallization speed becomes slow as the number of rewritable times increases. There is a problem that the reproduction signal strength becomes insufficient when the number of rewritable times is increased.

Therefore, an object of the present invention is to achieve good recording / recording.
An object of the present invention is to provide an information recording thin film capable of being rewritten many times while maintaining reproduction characteristics, a manufacturing method thereof, and an information recording medium using the thin film.

In the method disclosed in Japanese Patent Laid-Open No. 3-292632, a Sb ₂ Se ₃ film is used, and the reflectance is changed by partially changing the phase in the scanning spot of the reading light to change the reflectance within the high reflectance region. Read only the phase pit. This method cannot be applied to phase-change type optical disks, magneto-optical disks, etc. other than the optical disk in which information is recorded by phase pits, because the melting point of the film is high and the laser irradiation power is high. Furthermore, when the reading is repeated many times, the flow of the film,
There are drawbacks such as segregation occurring little by little and the number of times of super-resolution readout is small. Further, the medium described in Japanese Patent Application Laid-Open No. 5-73961 uses a molten mask layer and partially melts in the scanning spot of the reading light to change the reflectance, thereby apparently reducing the spot size. In this medium, a melting mask layer having a low melting point is used, and since the viscosity is low,
When the reading is repeated a number of times, there are drawbacks such as film flow and segregation little by little, and the number of times super-resolution reading is possible is small.

Therefore, another object of the present invention is to solve the above-mentioned drawbacks of the prior art, and to convert analog information signals such as video signals and audio signals, digital information such as computer data, facsimile signals and digital audio signals. To provide a thin film for super-resolution reading, which can be applied to optical discs in which signals are recorded by unevenness, phase-change type optical discs, magneto-optical discs, etc., and by which flow and segregation are prevented to increase the number of times super-resolution reading is possible It is in.

[0012]

[Means for Solving the Problems]

(1) A first information recording thin film of the present invention is for information recording, which is formed on a substrate directly or through a protective layer and records / reproduces information by an atomic arrangement change caused by irradiation of an energy beam. In the thin film, the average composition in the film thickness direction of the information recording thin film is represented by the general formula Sb _x Te _y A _p B _q C _r (1), wherein A is selected from the first group consisting of Ge and In. At least one element, B is a lanthanoid element (La, Ce, Pr, Nd, Pm, Sm, Eu,
Gd, Tb, Dy, Ho, Er, Tm, Yb and L
u) and Ag, Ba, Co, Cr, Ni, Pt, S
i, Sr, Au, Cd, Cu, Li, Mo, Mn, Z
n, Al, Fe, Pb, Na, Cs, Ga, Pd, B
at least one element selected from the second group consisting of i, Sn, Ti and V, C is Sb, Te and A
And at least one element other than the element represented by B, wherein the units of x, y, p, q and r are all atomic percentages, and 2 ≦ x ≦ 41 and 25 ≦ y, respectively.
≦ 75, 0.1 ≦ p ≦ 60, 3 ≦ q ≦ 40, 0.1 ≦ r
It is characterized by being in the range of ≦ 30.

(2) The second information recording thin film of the present invention records / reproduces information by a change in atomic arrangement which is formed on a substrate directly or through a protective layer and which is caused by irradiation with an energy beam. In the information recording thin film, the average composition in the film thickness direction of the information recording thin film is represented by the general formula Sb _x Te _y A _p B _q (2), where A is from the first group consisting of Ge and In. At least one element selected, B is a lanthanoid element and Ag, Ba, Co, Cr, Ni, Pt, S
i, Sr, Au, Cd, Cu, Li, Mo, Mn, Z
n, Al, Fe, Pb, Na, Cs, Ga, Pd, B
represents at least one element selected from the second group consisting of i, Sn, Ti and V, and is represented by the above x, y, d and e.
All units are atomic percentages, and 2 ≦ x ≦
41, 25 ≤ y ≤ 75, 0.1 ≤ p ≤ 60, 3 ≤ q ≤ 4
It is characterized by being in the range of 0.

This corresponds to the first information recording thin film excluding the element represented by C.

(3) The third information recording thin film of the present invention records / reproduces information by an atomic arrangement change formed on a substrate directly or through a protective layer and caused by irradiation with an energy beam. In the information recording thin film, the average composition in the film thickness direction of the information recording thin film is represented by the general formula: Sb _x Te _y B _q C _r (3), wherein B is a lanthanoid element and Ag, B
a, Co, Cr, Ni, Pt, Si, Sr, Au, C
d, Cu, Li, Mo, Mn, Zn, Al, Fe, P
b, Na, Cs, Ga, Pd, Bi, Sn, Ti and V, at least one element selected from the group consisting of Sb, Te and at least one element other than B. , Said x, y, e and f
All units are atomic percentages, and 2 ≦ x ≦
41, 25 ≦ y ≦ 75, 3 ≦ q ≦ 40, 0.1 ≦ r ≦ 3
It is characterized by being in the range of 0.

This corresponds to the first information recording thin film excluding the element represented by A.

(4) The fourth information recording thin film of the present invention records / reproduces information by a change in atomic arrangement which is formed on a substrate directly or through a protective layer and which is caused by irradiation with an energy beam. In the information recording thin film, the average composition in the film thickness direction of the information recording thin film is represented by the general formula: Sb _x Te _y B _q (4), wherein B is a lanthanoid element and Ag, B
a, Co, Cr, Ni, Pt, Si, Sr, Au, C
d, Cu, Li, Mo, Mn, Zn, Al, Fe, P
represents at least one element selected from the group consisting of b, Na, Cs, Ga, Pd, Bi, Sn, Ti and V, and the units of x, y and e are all atomic percentages, and 2 ≦ x ≤ 41, 25 ≤ y ≤ 75, 3 ≤ q
It is characterized by being in the range of ≦ 40.

This corresponds to the first information recording thin film excluding the elements represented by A and C.

(5) The information recording thin film of the present invention is for information recording / reproducing, which is formed on a substrate directly or through a protective layer and changes or changes the atomic arrangement caused by the irradiation of an energy beam. In the thin film, the average composition of the information recording thin film is represented by the general formula (Ge _a Sb _b Te _c ) _1-d X _d (5), where X is Cr and Ag, Ba, Co, N.
i, Pt, Si, Sr, Au, Cd, Cu, Li, M
o, Mn, Zn, Al, Fe, Pb, Na, Cs, G
a, Pd, Bi, Sn, Ti, V, In and at least one element consisting of a lanthanoid element, wherein a, b, c and d are each 0.02 ≦ a ≦ 0.1
9, 0.04 ≦ b ≦ 0.4, 0.5 ≦ c ≦ 0.75
It is characterized by being in the range of 0.03 ≦ d ≦ 0.3.

(6) The thin film for information recording of the present invention is for information recording, which is formed on a substrate directly or through a protective layer and records / reproduces information by an atomic arrangement change caused by irradiation of an energy beam. In the thin film, the average composition of the information recording thin film is represented by the general formula (Ge _a Sb _b Te _c ) _1-d X _d (5), where X is Cr and Ag, Ba, Co, N.
i, Pt, Si, Sr, Au, Cd, Cu, Li, M
o, Mn, Zn, Al, Fe, Pb, Na, Cs, G
a, Pd, Bi, Sn, Ti, V, In and at least one element consisting of a lanthanoid element, wherein a, b, c and d are each 0.25 ≦ a ≦ 0.
65,0 ≦ b ≦ 0.2, 0.35 ≦ c ≦ 0.75, 0.
It is characterized in that it is in the range of 03 ≦ d ≦ 0.3.

(7) The information recording thin film as described in any one of 1 to 6 above is characterized in that the B or X has a concentration gradient in the film thickness direction.

(8) The information recording thin film as described in any one of 1 to 6 above, which contains a precipitate composed of a high melting point component having a relatively higher melting point than the remaining component of the thin film, and the precipitate is It is characterized by containing the element represented by B or X.

(9) The information recording thin film as described in any one of 2, 5 and 6 above, which contains a precipitate of a high melting point component having a relatively higher melting point than the remaining component of the thin film, and has a high melting point. It is characterized in that at least a part of the components is present on the light incident side of the thin film in the form of a discontinuous film in the range of an average film thickness of 1 to 10 nm.

(10) In the information recording thin film as described in any one of the above 2, 5 and 6, the high melting point contains a precipitate composed of a high melting point component having a relatively higher melting point than the remaining component of the thin film. The sum of the number of atoms of the constituent elements of the component is in the range of 10 to 50% with respect to the sum of the total number of atoms of the constituent elements of the thin film.

(11) In the information recording thin film as described in any one of the above 2, 5 and 6, the high melting point contains a precipitate of a high melting point component having a relatively higher melting point than the remaining component of the thin film. It is characterized in that the component contents change in the film thickness direction.

(12) The thin film for information recording as described in any one of the above 2, 5 and 6, which contains a precipitate composed of a high melting point component having a melting point relatively higher than that of the remaining component of the thin film. When the average composition of L _j H _k (6) is expressed by the low melting point component L of the element alone or the compound composition and the high melting point component H of the element alone or the compound composition, 20 ≦ k / (j + K) ≦ 40 ( 7)
Is used as the standard composition, and the content of each element in the film is within the range of the value determined by the above formula ± 10 atomic%.

(13) In the information recording thin film as described in any one of the above 2, 5 and 6, the high melting point contains a precipitate composed of a high melting point component having a relatively higher melting point than the remaining component of the thin film. The melting point of the component is 780 ° C. or higher.

(14) In the information recording thin film as described in any one of the above 2, 5 and 6, the high melting point contains a precipitate composed of a high melting point component having a relatively higher melting point than the remaining component of the thin film. The difference between the melting points of the components and the melting points of the remaining components of the thin film is 150 ° C. or more.

(15) In the information recording thin film as described in any one of the above 2, 5 and 6, the high melting point contains a precipitate composed of a high melting point component having a relatively higher melting point than the remaining component of the thin film. It is characterized in that the precipitates of the components are distributed in the inside of the thin film in a granular or columnar shape.

(16) In the information recording thin film as described in any one of the above 2, 5 and 6, the high melting point contains a precipitate of a high melting point component having a melting point relatively higher than that of the remaining component of the thin film. The maximum outer dimension of the component precipitates in the film surface direction of the thin film is 5 nm or more and 50 nm or less.

(17) The information recording thin film as described in any one of 2, 5 and 6 above, which contains a precipitate composed of a high melting point component having a relatively higher melting point than the remaining component of the thin film, and has a high melting point. The precipitate of the component extends in a columnar shape in the film thickness direction from both interfaces of the thin film, the length of the precipitate in the film thickness direction is 5 nm or more, and is (1/2) or less of the film thickness of the thin film. Is characterized in that.

(18) The information recording thin film as described in any one of 2, 5 and 6 above, which contains a precipitate composed of a high melting point component having a relatively higher melting point than the remaining component of the thin film, and has a high melting point. The precipitate of the component extends in a column shape from one interface of the thin film in the film thickness direction thereof, and the length of the precipitate in the film thickness direction is 10 nm or more and not more than the film thickness of the thin film. 10. The information recording thin film according to 10.

(19) In the information recording thin film as described in any one of the above 2, 5 and 6, the high melting point contains a precipitate composed of a high melting point component having a relatively higher melting point than the remaining component of the thin film. The length of the component precipitate in the film thickness direction is 10 nm
As described above, the film thickness is equal to or less than the film thickness of the thin film.

(20) In the information recording thin film described in any one of the above 2, 5 and 6, the thin film for information recording contains a precipitate composed of a high melting point component having a melting point relatively higher than that of the remaining component of the thin film, and is adjacent to each other. The straight line connecting the centers of the two high melting point component precipitates is characterized in that the length passing through the region between the precipitates in the film surface direction of the thin film is 15 nm or more and 70 nm or less.

(21) The information recording thin film as described in any one of 2, 5 and 6 above, which contains a porous precipitate composed of a high melting point component having a relatively higher melting point than the remaining components of the thin film. The residual component is distributed in the pores of the porous precipitate.

(22) The information recording thin film as described in any one of 2, 5 and 6 contains a porous precipitate composed of a high melting point component having a relatively higher melting point than the remaining component of the thin film. The maximum pore size of the porous precipitates of the high melting point component in the film surface direction of the thin film is 80 nm or less,
The maximum wall thickness in the film surface direction of the thin film in the region between two adjacent holes is 20 nm or less.

(23) The information recording thin film as described in any one of the above 2, 5 and 6, wherein the thin film contains a precipitate composed of a high melting point component having a melting point relatively higher than that of the remaining component of the thin film. Is characterized in that the melting point of the remaining component is 650 ° C. or lower.

(24) The information recording thin film as described in any one of the above 2, 5 and 6, wherein the thin film contains a precipitate composed of a high melting point component having a relatively higher melting point than the remaining component of the thin film. Is characterized in that the melting point of the remaining component is 250 ° C. or lower.

(25) The information recording thin film as described in any one of the above 2, 5 and 6, wherein the thin film contains a precipitate composed of a high melting point component having a melting point relatively higher than that of the remaining component of the thin film. At least one of the real number part and the imaginary number part of the complex refractive index of is changed by 20% or more from that before irradiation by light irradiation.

(26) In an information recording thin film which is formed on a substrate directly or through a protective layer and which records and reproduces information by a change in atomic arrangement caused by irradiation with an energy beam, It is characterized in that it contains a precipitate composed of a high melting point component having a relatively high melting point, and the precipitate is distributed in a region composed of the remaining component of the thin film.

(27) In the information recording thin film described in (26), the maximum outer dimension of the precipitate of the high melting point component in the film surface direction of the thin film is 5 nm or more and 50 nm or less.

(28) In the thin film for information recording as described in 26 above, the precipitate of the high melting point component extends in a column shape in the film thickness direction from both interfaces of the thin film, and the film thickness of the precipitate. The length in the direction is 5 nm or more and is (1/2) or less of the film thickness of the thin film.

(29) In the thin film for information recording as described in 26 above, the precipitate of the high melting point component extends in a column shape in the film thickness direction from one interface of the thin film, and the film thickness of the precipitate. The length in the direction is 10 nm or more and is less than or equal to the film thickness of the thin film.

(30) In the information recording thin film as described in 26 above, the length of the precipitate of the high melting point component in the film thickness direction is 10 nm or more and is less than or equal to the film thickness of the thin film.

(31) In the thin film for information recording as described in 26 above, a straight line connecting the centers of two adjacent precipitates of the high melting point component is a region between the precipitates in the film surface direction of the thin film. The length passing through is not less than 15 nm and not more than 70 nm.

(32) In a thin film for information recording, which is formed on a substrate directly or through a protective layer and records / reproduces information by a change in atomic arrangement caused by irradiation of an energy beam, A thin film for information recording, comprising a porous precipitate composed of a high melting point component having a relatively high melting point, and the remaining component of the thin film being distributed in the pores of the porous precipitate.

(33) In the information recording thin film as described in 32 above, the maximum inner dimension in the film surface direction of the thin film of the porous precipitate of the high melting point component is 80 nm or less,
The maximum wall thickness in the film surface direction of the thin film in the region between two adjacent holes is 20 nm or less.

(34) In the information recording thin film as described in 26 or 32 above, the melting point of the remaining component of the thin film is 650.
It is characterized by being below ° C.

(35) In the information recording thin film as described in 32 or 32 above, the melting point of the remaining component of the thin film is 250.
It is characterized by being below ° C.

(36) In the information recording thin film as described in any one of 26 and 32, at least one of the real part and the imaginary part of the complex refractive index of the thin film is 20 with respect to that before irradiation by light irradiation. It is characterized by changing by more than%.

(37) In the information recording thin film as described in 26 or 32 above, the sum of the numbers of atoms of the constituent elements of the high melting point component is 10 to 50 with respect to the sum of the total number of atoms of the thin film. It is characterized by being in the range of%.

(38) In the information recording thin film as described in any one of 26 and 32, the average composition is L _j H by the low melting point component L of the element simple substance or the compound composition and the high melting point component H of the element simple substance or the compound composition. _When expressed by the equation of _k (6), 20 ≦ k / (j + K) ≦ 40 (7)
Is used as the standard composition, and the content of each element in the film is within the range of the value determined by the above formula ± 10 atomic%.

(39) In the information recording thin film as described in any one of 26 and 32 above, the high melting point component has a melting point of 780 ° C. or higher.

(40) In the information recording thin film as described in any one of 26 and 32, the difference between the melting point of the high melting point component and the melting point of the remaining component of the thin film is 150 ° C. or more. To do.

(41) The information recording thin film as described in any one of 2, 5 and 6 above, which contains a precipitate composed of a high melting point component having a melting point relatively higher than that of the remaining component of the thin film. Alternatively, the element represented by X is preferably Mo and Si, Pt, Co, Mn, W,
Cr is particularly preferable.

(42) In a method of manufacturing a thin film for information recording, which is formed directly on a substrate or through a protective layer and records / reproduces information by an atomic arrangement change caused by irradiation with an energy beam, The method is characterized by comprising a step of forming a thin film directly or through a protective layer, and a step of irradiating the thin film with an energy beam to generate or grow a high melting point component in the thin film.

(43) In a method of manufacturing an information recording thin film, which is formed directly on a substrate or through a protective layer and records / reproduces information by an atomic arrangement change caused by irradiation of an energy beam, Forming an island-shaped seed crystal by depositing a material having a high melting point component or a material having a composition close to that of the high melting point component directly or through a protective layer, and the high melting point component on the seed crystal. And depositing a material containing the residual component, selectively growing the high melting point component on the seed crystal, and growing the residual component so as to fill the space between the seed crystals. It is characterized by

The average film thickness of the film for forming the island-shaped seed crystal is preferably 1 nm or more and 10 nm or less. 1n
If it is less than m, the effect of growing the high melting point component is small,
If it exceeds 10 nm, it causes an increase in noise.

In this method, the high melting point component is likely to grow from the interface on one side of the information recording thin film toward the inside thereof.

In the first and second methods for manufacturing the information recording thin film, known methods such as vacuum vapor deposition, gas vapor deposition, sputtering, ion beam vapor deposition, ion plating and electron beam vapor deposition are used for forming the film. Although it can be used, it is preferable to use sputtering.

In the case of sputtering, in the method of sputtering with a target having the composition of the recording thin film, the uniformity in the film is good and the noise can be reduced. On the other hand, the rotary co-sputtering method using a target having a composition of a high melting point component and a target having a composition of a remaining component can accelerate the precipitation of the high melting point component and is effective in extending the number of rewritable times.

(44) In a method of manufacturing a thin film for information recording, which is formed directly on a substrate or through a protective layer and records or reproduces information by a change in atomic arrangement caused by irradiation with an energy beam, The method is characterized by including a step of changing the content of the high melting point component in the film thickness direction when forming a film composed of the phase change component and the high melting point component directly or through the protective layer.

(45) An information recording medium provided with the information recording thin film described in any one of 1 to 6, 26 and 32 as a recording layer.

(46) An information recording medium comprising the information recording thin film described in any one of 1 to 6, 26 and 32 as a mask layer for super-resolution reading.

(47) An information recording medium comprising the information recording thin film described in any one of 1 to 6, 26 and 32 as a reflective layer for super-resolution reading.

(48) The melting point of the residual component after the precipitation of the high melting point component is 650 ° C. or less, 1 to 6, 26
And an information recording medium according to any one of 32.

(49) An information recording medium provided with the information recording thin film as described in 47 or 48 of any one of 1 to 6, 26 and 32 as a reflective layer for super-resolution reading,
The reflectance of the reflective layer is 60% or more.

(50) An information recording medium for recording or reproducing information, which is formed on a substrate directly or via a protective layer and changes or changes in atomic arrangement caused by irradiation of an energy beam. 32. An information recording thin film according to any one of 32) is provided as a recording layer or a mask layer for super-resolution reading, and has an intermediate two-layer structure of a SiO ₂ layer on the reflective layer side and a ZnS—SiO ₂ layer on the recording film side. It is characterized by comprising layers.

(51) In an information recording medium which is formed on a substrate directly or via a protective layer and which records or reproduces information by a change in atomic arrangement caused by irradiation with an energy beam, directly or on the substrate An information recording thin film for recording or reproducing information by an atomic arrangement change caused by irradiation of an energy beam, formed as a recording layer or a mask layer for super-resolution reading, and Si-Sn, Si At least one of —Ge and Si—In compounds, or a reflective layer having a composition close to this is provided.

(52) In an information recording medium which is formed directly on a substrate or via a protective layer and which records or reproduces information by an atomic arrangement change caused by irradiation with an energy beam, directly or on the protective layer. A thin film for information recording, which records or reproduces information by an atomic arrangement change caused by irradiation of an energy beam, formed as a recording layer or a mask layer for super-resolution reading, and a film thickness of a reflective layer Is 150 nm or more and 300 nm or less.

(53) In an information recording medium, which is formed on a substrate directly or via a protective layer and records or reproduces information by a change in atomic arrangement caused by irradiation with an energy beam, directly or on the substrate An information recording thin film for recording or reproducing information by an atomic arrangement change caused by irradiation of an energy beam, formed as a recording layer or a mask layer for super-resolution reading, ZnS-S on _two layers and recording film side
A protective layer having a two-layer structure of an iO ₂ layer is provided.

(54) The material of the protective layer 2 and the intermediate layer 4 is ZnS-SiO ₂ , Si-N-based material, Si-O-N.
Materials, SiO ₂ , SiO, Ta ₂ O ₅ , TiO ₂ , Al ₂
O ₃ , Y ₂ O ₃ , CeO, La ₂ O ₃ , In ₂ O ₃ , GeO,
GeO ₂ , PbO, SnO, SnO ₂ , Bi ₂ O ₃ , TeO
₂ WO ₂ , WO ₃ , Sc ₂ O ₃ , ZrO ₂ and other oxides, Ta
_{N, AlN, Si 3 N 4} , Al-Si-N material (e.g., AlSiN ₂₎ nitride such _{as, ZnS, Sb 2 S 3,} Cd
S, In ₂ S ₃ , Ga ₂ S ₃ , GeS, SnS ₂ , PbS,
Bi ₂ S ₃ , etc. sulfides, SnSe ₂ , Sb ₂ Se ₃ , C
dSe, ZnSe, In ₂ Se ₃ , Ga ₂ Se ₃ , GeS
e, GeSe ₂ , SnSe, PbSe, Bi ₂ Se ₃ and other selenides, CeF ₃ , MgF ₂ , CaF ₂ and other fluorides, Si, Ge, TiB ₂ , B ₄ C, B, C, or the above It is preferable to use a material having a composition close to that of the material. Further, it may be a layer of these mixed materials or a multilayer of these.

In the case of multiple layers, a material containing 70 mol% or more of ZnS, for example, ZnS-SiO ₂ and a material containing 70 atomic% or more of at least one of Si and Ge, for example, S.
A two-layer film of i or Si oxide such as SiO ₂ is preferable. In this case, in order to prevent deterioration of recording sensitivity, Zn
The S-SiO ₂ layer is provided on the recording film side, and the thickness is 3n.
m or more. Further, in order to exert the effect of suppressing the flow of the recording film due to the low thermal expansion coefficient of the SiO ₂ layer, the thickness is 10 nm.
The following are preferred. This two-layer film is preferably provided instead of the protective layer 2, but may be provided instead of the intermediate layer 4. As a substitute for the protective layer 2, the thickness of the SiO ₂ layer is preferably 50 nm or more and 250 nm or less. When a two-layer film is provided instead of the intermediate layer, the thickness of the SiO ₂ layer is 10 nm or more and 80
nm or less is preferable. Providing these two-layer films is
It is preferable not only when using the recording film of the present invention, but also when using other phase change recording films.

When the refractive index of the intermediate layer 4 is in the range of 1.7 or more and 2.3 or less, the film thickness is preferably 3 nm or more and 100 nm or less, and 180 nm or more and 400 nm or less.

As the material of the reflection layer 5, Al--Ti, S
Since the i-Ge mixed material can make the light absorptance of the recording mark portion smaller than the light absorptance of the portion other than the recording mark, it is possible to prevent the unerased portion due to the difference in the light absorptance, and further the rewritable number does not decrease, which is preferable . The content of Ge is preferably 10 atomic% or more and 80 atomic% or less, because the number of rewritable times is less likely to decrease.

Next, Si—Sn or Si—In mixed material, or a mixed material of two or more kinds of these mixed materials can obtain similar results and is preferable. These reflective layer materials are preferable not only for the phase change film of the present invention, but also for the reflective layer material when other phase change films are used, because the number of rewritable times does not decrease as compared with the conventional materials.

Furthermore, Si, Ge, C, Au, Ag, C
u, Al, Ni, Fe, Co, Cr, Ti, Pd, P
A single element of t, W, Ta, Mo, Sb, an alloy containing them as a main component, or a layer made of an alloy of these elements may be used, or a multi-layer made of these layers may be used. Alternatively, a composite layer of these and another substance such as an oxide may be used.

In this embodiment, the polycarbonate substrate 1 having the irregularities such as the tracking guide directly formed on the surface thereof is used.
However, instead of this, polyolefin, epoxy, acrylic resin, chemically strengthened glass having an ultraviolet curable resin layer formed on its surface, or the like may be used.

A simple laminated structure in which a part of the intermediate layer 4, the reflective layer 5 and the protective layer 2 is omitted, for example, substrate 1 / protective layer 2 / recording film 3, substrate 1 / recording film 3 / intermediate layer 4, substrate 1 / Even with the configuration of the recording film 3 / reflection layer 5, etc.,
Even if the rewriting is performed many times, the noise increase is small and good results are obtained, which is preferable.

As described above, the information recording thin film of this embodiment maintains good recording / reproducing / erasing characteristics,
It is possible to rewrite a number of times as compared with the conventional method. Also, record
There is also an advantage that the power of the laser light used for erasing may be low.

(55) The thin film for super-resolution reading of the present invention which produces a super-resolution effect upon irradiation with a beam for super-resolution reading is characterized by containing a phase change component and a precipitated high melting point component. . The super-resolution readout thin film is formed directly on the substrate or via a protective layer made of at least one of an inorganic substance and an organic substance.

(56) The high melting point component having a relatively higher melting point than the phase change component is precipitated as columnar or massive precipitates or as porous precipitates.

(57) The average composition of the super-resolution readout thin film can be represented by the following general formula.

D _e E _f F _g (8) where E is Sn, Pb, Bi, Zn, Ga, In
At least one element selected from
B, C, N, O, S, Se, Si, Te, Ag, Al,
Au, Ba, Be, Ca, Cd, Co, Cr, Cs, C
u, Fe, Ge, Hf, Hg, Ir, K, Li, Mg,
Mn, Mo, Na, Nb, Ni, Os, Pd, Pt, R
b, Re, Rh, Ru, Sb, Sc, Sr, Ta, T
i, V, W, Y and Zr represent at least one element selected from the group consisting of i, V, W, Y and Zr, and F represents at least one element other than those represented by D and E.
It can be 1, Br, Cl, F, H, I, P, etc. The units of e, f and g are all atomic percentages, and are 30 ≦ e ≦ 95, 5 ≦ f ≦ 50 and 0, respectively.
It is preferably in the range of ≦ g ≦ 20. Furthermore, 40
More preferably, the ranges are ≦ e ≦ 87, 13 ≦ f ≦ 40, and 0 ≦ g ≦ 10.

The element represented by F is, for example, D described above.
If the elements represented by E and E are Sn and Te, respectively, any element other than Sn and Te may be used. In addition, the above-mentioned D, D '(wherein the above-mentioned D is D, D'2 like Sn, Zn).
In the case of elements), E and F in combination, D-E, E-
It is preferable that the high melting point component formed by the combination of F and D'-E does not have a eutectic point, or even if it has a eutectic point, the melting point is 150 ° C or more higher than the melting points of D and DD '.

(58) The thin film for super-resolution reading is
An average composition represented by the following general formula can be used.

Se _p M _q N _r O _s (11) where M is In, Sb, Bi, Te, Au, B,
At least one element selected from Cs, Sn, Tl, S, Ge, Fe, Zn, and N is As, C, N, O, S
i, Ag, Al, Ba, Be, Ca, Cd, Co, C
r, Cu, Hf, Hg, Ir, K, Li, Mg, Mn,
Mo, Na, Nb, Ni, Os, Pd, Pt, Rb, R
e, Rh, Ru, Sc, Sr, Ta, Ti, V, W,
It represents at least one element other than the elements represented by Y, Zr, Pb, Ga, U, Se and M. O represents at least one element other than those represented by Se and M and N, such as Br, Cl, F, H, I, and P.
Can be The units of p, q, r, and s are all atomic percentages, and 40 ≦ p ≦ 9.
5, 0 ≦ q ≦ 55, 5 ≦ r ≦ 50, and 0 ≦ s ≦ 20 are preferable, and 50 ≦ p ≦ 80 and 0 ≦ q ≦ 4.
More preferably, it is in the range of 0, 10 ≦ r ≦ 40, and 0 ≦ s ≦ 10.

(59) When the average composition of the thin film for super-resolution reading is expressed by the following equation from the low melting point component L of the element simple substance or the compound composition and the high melting point component H of the element simple substance or the compound composition, L _j H _k (6) With the composition in the range of the following formula (7) as the reference composition, the content of each element constituting the above thin film in the film is within the range of ± 10 atom% determined by the formula (7). Is preferred, and more preferably within the range of ± 5 atom%.

20 ≦ k / (j + k) ≦ 40 (7) For example, the reference composition of the super-resolution readout film is (GeSb ₂
Te ₄ ) ₈₀ (Cr ₄ Te ₅ ) ₂₀ , L in the formula (7) is GeSb ₂ Te ₄ , H is Cr ₄ Te ₅ , and k /
(J + k) is 20. Here, the atomic% of each element is 11% for Ge of L, 23% for Sb, and 46 for Te.
%, Cr of H is 9%, and Te is 11%. Therefore, in the range of ± 10 atom% determined by the formula (7), Ge of L is 1 to
21%, Sb 13-33%, Te 36-56%, H
Cr is 0 to 19% and Te is 1 to 21%.

(60) Both the low-melting point component and the high-melting point component preferably contain a metal or metalloid element in an amount of 50 atomic% or more, and more preferably 65 atomic% or more.

(61) The compositions of the above formulas (8) and (11) can be used as a phase change recording film and also as a phase change recording film of a recording medium which does not use a super-resolution readout thin film. When this recording film is used, a medium having a large difference in reflectance due to crystallization and amorphization can be manufactured.

The sum of the number of atoms of the high melting point component is 10 to 5 in proportion to the sum of the total number of atoms of the constituent elements of the super-resolution readout film.
It is preferably in the range of 0%, and more preferably in the range of 20 to 40%.

(62) In the combination of the high melting point component and the phase change component, it is preferable that the same element is present in each component in the range of 30 atom% or more and 80 atom% or less.

The melting point of the high melting point component is preferably 150 ° C. or more higher than the melting point of the phase change component which is the residual component after precipitation.

(63) The average composition of the high melting point component may be at least one of the following Group A, or a composition close to this, or a compound having a melting point of 800 ° C. or higher. Here, the composition close to this means that the deviation from the listed composition is within ± 10 atom% (hereinafter,
the same). For example, in the case of BaPd ₂ , the atomic% of each element is 33% for Ba and 67% for Pd. Therefore, in the range where the deviation from the composition BaPd ₂ is ± 10 atomic%, Ba is 23 to 43% and Pd is 57 to 77%.

<Group A> BaPd ₂ , BaPd ₅ , NdP
d, NdPd ₃ , NdPd ₅ , Nd ₇ Pt ₃ , Nd ₃ Pt
₂ , NdPt, Nd ₃ Pt ₄ , NdPt ₂ , NdP
t ₅ , Bi ₂ Nd, BiNd, Bi ₃ Nd ₄ , Bi ₃ Nd
₅ , BiNd ₂ , Cd ₂ Nd, CdNd, Mn ₂ Nd, M
n ₂₃ Nd ₆ , Mn ₁₂ Nd, Nd ₅ Sb ₃ , Nd ₄ Sb ₃ ,
NdSb, NdSb ₂ , Fe ₂ Nd, Fe ₁₇ Nd ₂ , C
s ₃ Ge ₂ , CsGe, CsGe ₄ , Nd ₅ Si ₃ , Nd
₅ Si ₄ , NdSi, Nd ₃ Si ₄ , Nd ₂ Si ₃ , Nd ₅
Si ₉ , Cs ₂ Te, NdTe ₃ , Nd ₂ Te ₅ , NdT
e ₂ , Nd ₄ Te ₇ , Nd ₂ Te ₃ , Nd ₃ Te ₄ , Nd
Te, Ce ₃ Ir, Ce ₂ Ir, Ce ₅₅ Ir ₄₅ , CeIr
₂ , CeIr ₃ , Ce ₂ Ir ₇ , CeIr ₅ , CaPd,
CaPd ₂ , CaGe, Ca ₂ Ge, GeNa ₃ , Ge
Na, CaSi ₂ , Ca ₂ Si, CaSi, Se ₂ Sr,
Se ₃ Sr ₂ , SeSr, GeSr ₂ , GeSr, Ge _{2
Sr, SnSr, Sn 3 Sr 5} , SnSr 2, Ce 2 T
1, Ce ₅ Tl ₃ , CeTl ₃ , Ce ₃ Tl ₅ , CeT
1, BaTl, Pd ₁₃ Tl ₉ , Pd ₂ Tl, Pd ₃ Tl,
Mg ₂ Si, Mg ₂ Ge, BaPd ₂ , BaPd ₅ , Ce
₄ Se ₇ , Ce ₃ Se ₄ , Ce ₂ Se ₃ , CeSe, Ce ₅
Ge ₃ , Ce ₄ Ge ₃ , Ce ₅ Ge ₄ , CeGe, Ce ₃ G
e ₅ , Ce ₅ Si ₃ , Ce ₃ Si ₂ , Ce ₅ Si ₄ , Ce
Si, Ce ₃ Si ₅ , CeSi ₂ , CeTe ₃ , Ce ₂ T
e ₅ , CeTe ₂ , Ce ₄ Te ₇ , Ce ₃ Te ₄ , CeT
e, La ₃ Se ₇ , LaSe ₂ , La ₄ Se ₇ , La ₂ S
e ₃ , La ₃ Se ₄ , LaSe, GeLa ₃ , Ge ₃ La
₅ , Ge ₃ La ₄ , Ge ₄ La ₅ , GeLa, Ge ₅ La
₃ , BaSe ₂ , Ba ₂ Se ₃ , BaSe, PdSe, M
o ₃ Se ₄ , MoSe ₂ , Ba ₂ Ge, BaGe ₂ , Ba
Ge, Ba ₂ Te ₃ , BaTe, Ge ₂ Pd ₅ , GeP
d ₂ , Ge ₉ Pd ₂₅ , GePd, Ge ₃ Pt, Ge ₃ P
t ₂ , GePt, Ge ₂ Pt ₃ , GePt ₂ , GePt
₃ , Pu ₃ Sn, Pu ₅ Sn ₃ , Pu ₅ Sn ₄ , Pu ₈ Sn
₇ , Pu ₇ Sn ₈ , PuSn ₂ , PuSn ₃ , Pt ₅ Te
₄ , Pt ₄ Te ₅ , PtTe ₂ , GeNi, Ge ₃ N
i ₅ , Ge ₂ Ni ₅ , GeNi ₃ , NiTe _0.85 , Ni
Te _0.775 , Ni ₃ ± _x Te _x , Cr ₁₁ Ge ₁₉ , CrG
e, Cr ₁₁ Ge ₈ , Cr ₅ Ge ₃ , Cr ₃ Ge, CrSi
₂ , Cr ₅ Si ₃ , Cr ₃ Si, Cr ₅ Te ₈ , Cr ₄ Te
₅ , Cr ₃ Te ₄ , Cr _1-x Te, Ge ₃ Mn ₅ , GeM
n ₂ , Mn ₆ Si, Mn ₉ Si ₂ , Mn ₃ Si, Mn ₅ Si
₂ , Mn ₅ Si ₃ , MnSi, Mn ₁₁ Si ₁₉ , Mn ₂ S
n, Mn _3.25 Sn, MnTe, Te ₂ W, FeGe ₂ ,
Fe ₅ Ge ₃ , Fe ₃ Ge, Fe ₂ Si, Fe ₅ Si ₃ , F
eSi, FeSi ₂ , Ge ₂ Mo, Ge ₄₁ Mo ₂₃ , Ge
₁₆ Mo ₉ , Ge ₂₃ Mo ₁₃ , Ge ₃ Mo ₅ , GeMo ₃ , M
o ₃ Si, Mo ₅ Si ₃ , MoSi ₂ , MoSn, MoS
n ₂ , Mo ₃ Te ₄ , MoTe ₂ , Si ₂ Ti, SiTi, Si
₄ Ti ₅ , Si ₃ Ti ₅ , SiTi ₃ , Sn ₅ Ti ₆ , Sn
₃ Ti ₅ , SnTi ₂ , SnTi ₃ , CoGe ₂ , Co ₅
Ge ₇ , CoGe, Co ₅ Ge ₃ , Co ₄ Ge, Co ₃ T
e ₄ , Ge ₇ Re ₃ , Re ₅ Si ₃ , ReSi, ReSi
₂ , Re ₂ Te.

(64) The average composition of the high melting point component is
At least one of the compounds listed in Group A and Group B below, or a composition close to this, or a melting point of 60.
The compound can be 0 ° C. or higher.

<Group B> Cs ₃ Ge, Ba ₂ Tl, GePd
₃ , Fe ₆ Ge ₅ , FeTe ₂ , Co ₅ Ge ₂ , Nd ₃ P
d, Cs ₃ Te ₂ , Ce ₄ Ir, NaPd, Ca ₉ Pd,
Ca ₃ Pd ₂ , Ca ₂ Ge, Se ₃ Sr, Ce ₃ Tl, Ce
Se ₂ , Ce ₃ Ge, BaSe ₃ , GeSe ₂ , GeS
e, BaTe ₂ , GePd ₅ , Ge ₈ Mn ₁₁ , MnTe
₂ , Ge ₃ W ₂ , FeGe, Fe ₄ Ge ₃ , Fe ₃ Sn,
_{Fe 3 Sn 2, FeSn, CoTe} 2.

(65) The average composition of the high melting point component is
At least one of the compounds listed in Group B and Group C below, or a composition close to this, or a melting point of 40.
The compound can be 0 ° C. or higher.

<Group C> Ba ₄ Tl, CsTe, Ba ₄ T
1, Ba ₁₃ Tl, Cd ₁₁ Nd, Cd ₆ Nd, Cs ₅ T
e ₄ , Ca ₃ Pd, Ca ₅ Pd ₂ , Sn ₃ Sr, Ba ₁₃ T
1, PdTl ₂ , FeSe ₂ , FeSe, Cr ₂ Te ₃ ,
CrTe ₃ , FeSn ₂ .

(66) When the compounds listed in Group A above are used as the high melting point component, the average composition of the phase change component is at least one of the compositions of Group D below, a composition close to this, or a melting point of 650. It is preferably a compound having a temperature of not higher than 0 ° C.

<Group D> Sn, Pb, Sb, Te, Zn,
Cd, Se, In, Ga, S, Tl, Mg, Tl ₂ S
e, TlSe, Tl ₂ Se ₃ , Tl ₃ Te ₂ , TlTe,
InBi, In ₂ Bi, TeBi, Tl-Se, Tl-
Te, Pb-Sn, Bi-Sn, Se-Te, SS
e, Bi-Ga, Sn-Zn, Ga-Sn, Ga-I
n, In ₃ SeTe ₂ , AgInTe ₂ , GeSb ₄ Te
₇ , Ge ₂ Sb ₂ Te ₅ , GeSb ₂ Te ₄ , GeBi ₄ T
e ₇ , GeBi ₂ Te ₄ , Ge ₃ Bi ₂ Te ₆ , Sn ₂ Sb
₆ Se ₁₁ , Sn ₂ Sb ₂ Se ₅ , SnSb ₂ Te ₄ , Pb ₂
Sb ₆ Te ₁₁ , CuAsSe ₂ , Cu ₃ AsSe ₃ , Cu
SbS ₂ , CuSbSe ₂ , InSe, Sb ₂ Se ₃ ,
Sb ₂ Te ₃ , Bi ₂ Te ₃ , SnSb, FeTe, Fe
₂ Te ₃ , FeTe ₂ , ZnSb, Zn ₃ Sb ₂ , VTe
₂ , V ₅ Te ₈ , AgIn ₂ , BiSe, InSb, I
n ₂ Te, In ₂ Te ₅ , Ba ₄ Tl, Cd ₁₁ Nd, Ba
₁₃ Tl, Cd ₆ Nd, Ba ₂ Tl.

(67) When using ones listed in the group B as the high melting point component, the average composition of the phase change components is at least one of the following compositions of the group E or a composition close to this, or a melting point of 450. It is preferably a compound having a temperature of not higher than 0 ° C.

<Group E> Sn, Pb, Te, Zn, Cd,
Se, In, Ga, S, Tl, Tl ₂ Se, TlSe,
Tl ₂ Se ₃ , Tl ₃ Te ₂ , TlTe, InBi, In
₂ Bi, TeBi, Tl-Se, Tl-Te, Pb-S
n, Bi-Sn, Se-Te, S-Se, Bi-Ga,
Sn-Zn, Ga-Sn, Ga-In, Ba 4 Tl.

(68) When the ones listed in Group C above are used as the high melting point components, the average composition of the phase change components is at least one of the following Group F compositions, or a composition close to this, or a melting point of 250. It is preferably a compound having a temperature of not higher than 0 ° C.

<F group> Sn, Se, In, Ga, S, I
nBi, In ₂ Bi, TeBi, Tl-Se, Tl-T
e, Pb-Sn, Bi-Sn, Se-Te, S-Se,
Bi-Ga, Sn-Zn, Ga-Sn, Ga-In.

(69) The composition or film thickness of the super-resolution reading thin film is preferably different on the inner and outer circumferences,
It is preferable that the peripheral portion of the track of the thin film for super-resolution reading is also crystallized. The thin film for super-resolution readout according to the present invention is
The present invention can be applied to any information recording medium such as a ROM disk on which information is already recorded and a RAM disk on which information can be recorded.

(70) The apparatus for super-resolution reading of an information recording medium provided with the thin film for super-resolution reading according to the present invention has a high melting point without melting the entire film even in the region of the highest temperature of the thin film for super-resolution reading. It is preferable to have a means for presetting or manually or automatically setting the super-resolution readout power in which the component remains in the solid phase. Further, it is preferable to have a unit for detecting a disorder of the reflected light intensity distribution at the time of super-resolution reading and a unit for adjusting the laser power according to the magnitude of the disorder. Further, it is preferable to have a means for increasing the laser power at the time of super-resolution reading to be at least twice as high as the power required for autofocusing or tracking, and more preferable to have means for increasing the laser power at least three times. This device can be used for media other than the present invention,
Better results are obtained than when the super-resolution readout laser power is constant.

(71) The super-resolution readout laser light is pulsed light, and the laser pulse period T, linear velocity v, spot diameter (λ / NA), and pulse width x have the following relationships (9) and (10). 0.4 λ / NA ≦ vT ≦ 1.5 λ / NA (9) 0.3 ≦ x / T ≦ 0.5 (10) Further, the following relationships (12) and (10) may be satisfied. More preferable.

0.5λ / NA ≦ vT ≦ 0.9λ / NA (12) (72) Information is obtained by a change in atomic arrangement that is formed on a substrate directly or through a protective layer and that is caused by irradiation with an energy beam. In the information recording thin film to be recorded / reproduced, by repeatedly irradiating the laser beam with an information recording / reproducing device or an initial medium crystallization device using an information recording medium having the thin film, relative to the remaining component of the thin film. A high-melting point component having a high melting point is deposited on the surface of the thin film, and the deposit is distributed in the region of the remaining components of the thin film.

(73) An information recording medium having an information recording thin film formed or formed on a substrate directly or through a protective layer for recording / reproducing information by an atomic arrangement change caused by irradiation of an energy beam is used. By repeatedly irradiating the laser beam in the information recording / reproducing method or the medium initial crystallization method, a high melting point component having a relatively higher melting point than the remaining component of the thin film is deposited, and the deposit is the remaining component of the thin film. It has the feature that it is distributed in the region consisting of.

(74) In the information recording thin film described in (1) to (6), a laser beam is repeatedly irradiated in an information recording / reproducing apparatus or a medium initial crystallization apparatus using an information recording medium having the thin film. By doing so, a high-melting point component having a melting point relatively higher than that of the remaining component of the thin film is deposited, the deposit is distributed in a region of the remaining component of the thin film, and the deposit is at least B and X. On the other hand, it is characterized by containing an element represented.

(75) A method for manufacturing an information recording medium, which is formed on a substrate directly or through a protective layer and records / reproduces information by a change in atomic arrangement caused by irradiation with an energy beam, A step of forming a protective layer, a recording film or a super-resolution reading film, an intermediate layer, and a reflective layer on the above, and a step of adhering another substrate or another substrate in which each of the layers is formed in the same manner to the medium; And irradiating with an energy beam to generate or grow a high-melting point component in the thin film.

(76) A method of manufacturing an information recording medium, which is formed directly on a substrate or through a protective layer and records / reproduces information by a change in atomic arrangement caused by irradiation with an energy beam, comprising: A step of forming a protective layer thereon, a step of depositing a material having a high melting point component or a material having a composition close to that of the high melting point component to form an island-shaped seed crystal, and An intermediate step of depositing a material containing a melting point component and the residual component, selectively growing the high melting point component on the seed crystal, and growing the residual component so as to fill the space between the seed crystals. The method is characterized by comprising a step of forming a layer and a reflective layer, and a step of adhering another substrate or another substrate on which each layer is similarly formed thereon to this.

(77) A method for manufacturing an information recording medium, which is formed directly on a substrate or through a protective layer and records or reproduces information by a change in atomic arrangement caused by irradiation with an energy beam, comprising: A step of forming a protective layer thereon, a step of changing the content of the high melting point component in the film thickness direction while forming a film composed of a phase change component and a high melting point component, and a step of forming an intermediate layer and a reflection layer And a step of adhering another substrate or another substrate on which each layer is formed in the same manner to the above.

(78) As the high melting point component, for example, LaTe ₃ , LaTe ₂ , La ₂ Te ₃ , La ₃ Te ₄ ,
LaTe, La ₂ Te ₅ , La ₄ Te ₇ , La ₃ Te, La ₂
Sb, La ₃ Sb ₂ , LaSb, LaSb ₂ , La ₃ Ge,
La ₅ Ge ₃ , La ₄ Ge ₃ , La ₅ Ge ₄ , LaGe, La
₃ Ge ₅ , Ag ₂ Te, Cr ₃ Te ₄ , Cr ₅ Te ₈ , Cr ₂ T
e ₃ , Cr ₄ Te ₅ , CrSb, Cr ₃ Ge, Cr ₅ Ge ₃ ,
Cr ₁₁ Ge ₈ , CrGe, Cr ₁₁ Ge ₁₉ , PtTe ₂ , P
t ₄ Te ₅ , Pt ₅ Te ₄ , Pt ₄ Sb, Pt ₃ Sb ₂ , Pt
Sb, Pt ₃ Ge, Pt ₂ Ge, Pt ₃ Ge ₂ , PtGe,
Pt ₂ Ge ₃ , PtGe ₃ , NiTe, NiTe _0.85 , N
iSb, Ni ₃ Ge, Ni ₅ Ge ₂ , Ni ₅ Ge ₃ , NiG
e, CoTe, CoTe ₂ , Co ₃ Te ₄ , CoSb, C
oSb ₂ , CoSb ₃ , Co ₅ Ge ₂ , Co ₅ Ge ₃ , CoG
e, Co ₅ Ge ₇ , CoGe ₂ , Si ₂ Te ₃ , SiSb,
_{SiGe, CeTe, Ce 3 Te 4} , Ce 2 Te 3, Ce 4
Te ₇ , CeTe ₂ , CeTe ₃ , Ce ₂ Sb, Ce ₅ S
b ₃ , Ce ₄ Sb ₅ , CeSb, CeSb ₂ , Ce ₃ Ge,
Ce ₅ Ge ₃ , Ce ₄ Ge ₃ , Ce ₅ Ge ₄ , CeGe, Ce
₃ Ge ₅ , Ce ₅ Si ₃ , Ce ₃ Si ₂ , Ce ₅ Si ₄ , CeS
i, Ce ₃ Si ₅ , CeSi ₂ , Cr ₃ Si, Cr ₅ Si ₃ ,
CrSi, CrSi ₃ , CrSi ₂ , Co ₃ Si, CoS
i, CoSi ₂ , NiSi ₂ , NiSi, Ni ₃ Si ₂ , N
i ₂ Si, Ni ₅ Si ₂ , Ni ₃ Si, Pt ₅ Si ₂ , Pt ₂
Si, PtSi, LaSi ₂ , Ag ₃ In, Ag ₂ In,
Bi ₂ Ce, BiCe, Bi ₃ Ce ₄ , Bi ₃ Ce ₅ , Bi
Ce ₂ , Cd ₁₁ Ce, Cd ₆ Ce, Cd ₅₈ Ce ₁₃ , Cd ₃
Ce, Cd ₂ Ce, CdCe, Ce ₃ In, Ce ₂ In,
Ce _{1 + x} In, Ce ₃ In ₅ , CeIn ₂ , CeIn ₃ , C
e ₂ Pb, CePb, CePb ₃ , Ce ₃ Sn, Ce ₅ Sn
₃ , Ce ₅ Sn ₄ , Ce ₁₁ Sn ₁₀ , Ce ₃ Sn ₅ , Ce ₃ Sn
₇ , Ce ₂ Sn ₅ , CeSn ₃ , CeZn, CeZn ₂ , C
_{eZn 3, Ce 3 Zn 11,} Ce 13 Zn 58, CeZn 5, C
_{e 3 Zn 22, Ce 2 Zn} 17, CeZn 11, Cd 21 Co 5,
CoGa, CoGa ₃ , CoSn, Cr ₃ Ga, CrG
a, Cr ₅ Ga ₆ , CrGa ₄ , Cu ₉ Ga ₄ , Cu ₃ Sn,
Cu ₃ Zn, Bi ₂ La, BiLa, Bi ₃ La ₄ , Bi ₃
La ₅ , BiLa ₂ , Cd ₁₁ La, Cd ₁₇ La ₂ , Cd ₉ L
a ₂ , Cd ₂ La, CdLa, Ga ₆ La, Ga ₂ La, G
aLa, Ga ₃ La ₅ , GaLa ₃ , In ₃ La, In ₂ L
a, In ₅ La ₃ , In _x La, InLa, InLa ₂ , I
nLa ₃ , La ₅ Pb ₃ , La ₄ Pb ₃ , La ₁₁ Pb ₁₀ , L
a ₃ Pb ₄ , La ₅ Pb ₄ , LaPb ₂ , LaPb ₃ , LaZ
n, LaZn ₂ , LaZn ₄ , LaZn ₅ , La ₃ Zn ₂₂ ,
La ₂ Zn ₁₇ , LaZn ₁₁ , LaZn ₁₃ , NiBi, G
a ₃ Ni ₂ , GaNi, Ga ₂ Ni ₃ , Ga ₃ Ni ₅ , GaN
i ₃ , Ni ₃ Sn, Ni ₃ Sn ₂ , Ni ₃ Sn ₄ , NiZn,
Ni ₅ Zn ₂₁ , PtBi, PtBi ₂ , PtBi ₃ , Pt
Cd ₂ , Pt ₂ Cd ₉ , Ga ₇ Pt ₃ , Ga ₂ Pt, Ga ₃ P
t ₂ , GaPt, Ga ₃ Pt ₅ , GaPt ₂ , GaPt ₃ ,
In ₇ Pt ₃ , In ₂ Pt, In ₃ Pt ₂ , InPt, In ₅
Pt ₆ , In ₂ Pt ₃ , InPt ₂ , InPt ₃ , Pt ₃ P
b, PtPb, Pt ₂ Pb ₃ , Pt ₃ Sn, PtSn, P
t ₂ Sn ₃ , PtSn ₂ , PtSn ₄ , Pt ₃ Zn, PtZ
n ₂ , AlS, Al ₂ S ₃ , BaS, BaC ₂ , CdS, C
o ₄ S ₃ , Co ₉ S ₈ , CoS, CoO, Co ₃ O ₄ , Co ₂
O ₃ , Cr ₂ O ₃ , Cr ₃ O ₄ , CrO, CrS, CrN,
Cr ₂ N, Cr ₂₃ C ₆ , Cr ₇ C ₃ , Cr ₃ C ₂ , Cu ₂ S,
Cu ₉ S ₅ , CuO, Cu ₂ O, In ₄ S ₅ , In ₃ S ₄ , L
a ₂ S ₃ , La ₂ O ₃ , Mo ₂ C, MoC, Mn ₂₃ C ₆ , Mn
₄ C, Mn ₇ C ₃ , NiO, SiS ₂ , SiO ₂ , Si
₃ N ₄ , Cu ₂ Te, CuTe, Cu ₃ Sb, Mn ₂ Sb,
MnTe, MnTe ₂ , Mn ₅ Ge ₃ , Mn _3.25 Ge, M
n ₅ Ge ₂ , Mn ₃ Ge ₂ , Ge ₃ W, Te ₂ W, AlSb,
Al ₂ Te ₃ , Fe ₂ Ge, FeGe ₂ , FeSb ₂ , Mo ₃
Sb ₇ , Mo ₃ Te ₄ , MoTe ₂ , PbTe, GeP
d ₂ , Ge ₂ Pd ₅ , Ge ₉ Pd ₂₅ , GePd ₅ , Pd ₃ S
b, Pd ₅ Sb ₃ , PdSb, SnTe, Ti ₅ Ge ₃ , G
e ₃₁ V ₁₇ , Ge ₈ V ₁₁ , Ge ₃ V ₅ , GeV ₃ , V ₅ Te ₄ ,
V ₃ Te ₄ , ZnTe, Ag ₂ Se, Cu ₂ Se, Al ₂ S
e ₃ , InAs, CoSe, Mn ₃ In, Ni ₃ In, N
There are high melting point compounds such as iIn, Ni ₂ In ₃ , Ni ₃ In ₇ , PbSe, high melting point compounds having a composition close to these, a mixture thereof, or a compound of three or more elements close to the mixed composition thereof.

Among these, LaSb, CrSb, C
oSb, Cr ₃ Te ₄ , Cr ₂ Te ₃ , Cr ₄ Te ₅ , CoT
e, Co ₃ Te ₄ , LaTe ₃ , Cu ₂ Te, CuTe, C
At least one of u ₃ Sb, MnTe, MnTe ₂ , and Mn ₂ Sb is particularly preferable. The reason is that since the refractive index is close to the residual component, noise is less likely to occur and the melting point is high.

The content of oxides, sulfides, nitrides, and carbides contained in the high melting point component is preferably less than 40 atom% of the total number of constituent atoms of the high melting point component, and less than 10 atom%. Is particularly preferable. The content of these is 4
If it is 0 atomic% or more, the difference in complex refractive index from the component other than the high melting point component of the thin film, that is, the residual component cannot be reduced, or oxygen or the like diffuses into the residual component to deteriorate the recording / reproducing characteristics. This is because it tends to cause problems such as causing problems.

In the information recording thin film, information is recorded / reproduced / erased in a state where the precipitates of the high melting point component are distributed. Therefore, the high melting point component and the reversible phase change component are used. It is preferable that it has a mixed composition of. Here, "phase change" includes not only a phase change between a crystalline state and an amorphous state but also a phase change between a crystalline state and a crystalline state.

As the reversible phase change component, any known phase change recording material can be used as long as it has suitable phase change characteristics. Examples of high melting point components Among the many compounds described above, a compound containing a transition metal element such as Cr is preferable, and the content of the transition metal element is preferably 40 atom% or less of the total number of constituent atoms of the thin film, and 34 atom % Or less is more preferable.
If this condition is satisfied, there is an advantage that the effect of reducing the interface reflectance between the precipitated high melting point component and the Te-based or Sb-based phase change component is increased.

The values of the real number part n ₁ and the imaginary number part k ₁ of the refractive index of the high melting point component are the crystals of the phase change component from the viewpoint of preventing light scattering at the interface between the high melting point component and the phase change component. The values of the real part n ₂ and the imaginary part k _{2 in} the state are preferably within ± 40%, and more preferably within ± 20%.

The difference between n ₁ and n ₂ is within ± 10%, the difference between k ₁ and k ₂ is within ± 70%, and | [(n ₁ + ik ₁ )-
(N ₂ + ik ₂ )] / [(n ₁ + ik ₁ ) + (n ₂ + i
It is preferable that the interface reflectance represented by k ₂ )] | ² be 6% or less. Also, the difference between n ₁ and n ₂ is within ± 10%, k ₁
And k ₂ are within ± 70%, and the interface reflectance is 2
% Or less is more preferable. It is preferable to satisfy these conditions in order to increase the film thickness and increase the reproduction signal level and prevent light scattering at the interface.

The preferred range of the refractive index (n, k) of the high melting point component is 5.0 ≦ n ≦ 6.2, 1.1 ≦ k ≦ 6 when the phase change component is Ge-Sb-Te system. When the phase change component is In—Sb—Te system, 1.5 ≦ n ≦ 1.8 and 0.6 ≦ k ≦ 3.6.

If the high melting point component cannot be clearly discriminated in the information recording thin film as described above,
Solve as follows. That is, when one of the compositions of the remaining components (for example, phase change components) other than the high melting point component is excluded from the average composition of the thin film, 80% or more, more preferably 90% or more of the balance is the melting point of the present invention. When the composition of the high melting point component satisfies the condition of, the high melting point component of the present invention is assumed to be precipitated.

"Protective layer" used for protecting the information recording thin film
May be an organic substance or an inorganic substance, but the inorganic substance is preferable in terms of heat resistance. However, if the inorganic protective layer formed separately from the substrate is thickened in order to increase the mechanical strength, cracking, lowering of transmittance, lowering of sensitivity are likely to occur. It is preferable to adhere a thick organic layer to the side opposite to the information recording thin film. This organic material layer may be a layer formed separately from the substrate or may be an organic material substrate. This makes deformation less likely to occur.

The organic protective layer is, for example, acrylic resin,
Polycarbonate, polyolefin, epoxy resin, polyimide, polyamide, polystyrene, polyethylene,
It can be formed of a fluororesin such as polyethylene terephthalate or polytetrafluoroethylene (Teflon). It may be an ethylene-vinyl acetate copolymer known as a hot melt adhesive, a pressure sensitive adhesive, or the like. You may form with the ultraviolet curing resin which has at least 1 of these resins as a main component. The organic substrate may also serve as the protective layer.

The inorganic protective layer is, for example, oxide, fluoride, nitride, sulfide, selenide, carbide, boride,
It can be formed of an inorganic material containing boron, carbon, or a metal as a main component. An inorganic substrate whose main component is glass, quartz, sapphire, iron, titanium, or aluminum may also serve as the protective layer.

Examples of the inorganic protective layer include Ce and L.
a, Si, In, Al, Ge, Pb, Sn, Bi, T
e, Ta, Sc, Y, Ti, Zr, V, Nb, Cr and oxide of at least one element selected from the group consisting of W, Cd, Zn, Ga, In, Sb, Ge, Sn, P
a sulfide or selenide of at least one element selected from the group consisting of b, a fluoride such as Mg, Ce, Ca,
A nitride of Si, Al, Ta, B or the like, or boron or carbon, for example, the main component is
CeO ₂ , La ₂ O ₃ , SiO, SiO ₂ , In ₂ O ₃ , Al
₂ O ₃ , GeO, GeO ₂ , PbO, SnO, SnO ₂ , B
i ₂ O ₃ , TeO ₂ , WO ₂ , WO ₃ , Ta ₂ O ₅ , Sc
₂ O ₃ , Y ₂ O ₃ , TiO ₂ , ZrO ₂ , CdS, ZnS, C
dSe, ZnSe, In ₂ S ₃ , In ₂ Se ₃ , Sb ₂ S ₃ ,
Sb ₂ Se ₃ , Ga ₂ S ₃ , Ga ₂ Se ₃ , MgF ₂ , Ce
F ₃ , CaF ₂ , GeS, GeSe, GeSe ₂ , Sn
S, SnS ₂ , SnSe, SnSe ₂ , PbS, PbS
e, Bi ₂ Se ₃ , Bi ₂ S ₃ , TaN, Si ₃ N ₄ , Al
N, AlSiN ₂ , Si, TiB ₂ , B ₄ C, SiC,
There is one having a composition close to or one of B and C, or a mixture thereof.

Of these, among sulfides, ZnS or a composition close to ZnS is preferable because the refractive index is appropriate and the film is stable. With nitride, the surface reflectance is not very high, and the film is stable and strong.
i ₃ N ₄ , AlSiN ₂ or AlN (aluminum nitride) or a composition close to it is preferable. In the case of oxide, Y ₂ O ₃ , Sc ₂ O ₃ and Ce are stable because the film is stable.
O ₂ , TiO ₂ , ZrO ₂ , SiO, Ta ₂ O ₅ , In
₂ O ₃ , Al ₂ O ₃ , SnO ₂ or SiO ₂ or a composition close to them is preferable. Amorphous Si containing hydrogen may be used.

When the protective layer has a multi-layered structure of two layers or three or more layers of inorganic substance-inorganic substance or inorganic substance-organic, the protective effect is further enhanced.

When a mixture is used for the protective layer, film formation is easy. For example, (Zn having a thickness of 50 to 500 nm
With the S) ₈₀ (SiO ₂ ) ₂₀ layer, the protective effect, the recording / erasing characteristics, and the rewriting characteristics are good, and the film formation is easy.

The protective layer can also be formed of a composite material of an organic substance and an inorganic substance.

The inorganic protective layer may be formed by electron beam vapor deposition, sputtering or the like with the same composition, but it may be formed by reactive sputtering or after forming a film of at least one element of metal, semimetal and semiconductor. The film formation is facilitated by reacting with at least one of sulfur, nitrogen and nitrogen.

Generally, when a thin film is irradiated with light, interference occurs due to superposition of the reflected light from the front surface of the thin film and the reflected light from the back surface of the thin film. Therefore, when a signal is read by changing the reflectance of the thin film, a "reflection layer" that reflects light in the vicinity of the recording thin film is provided to increase the effect of interference, thereby reproducing (reading) the signal. Can be increased. Note that an absorption layer that absorbs light may be used.

In order to enhance the effect of interference, it is preferable to provide an "intermediate layer" between the recording thin film and the reflective layer. The intermediate layer has a function of preventing mutual diffusion between the recording thin film and the reflective layer at the time of rewriting, and a function of reducing heat escape to the reflective layer to increase recording sensitivity and preventing unerased portion. There is.

By properly selecting the material of the intermediate layer, it is possible to play at least part of the role of the information recording thin film.
For example, if the intermediate layer is made of selenide, at least a part of the elements of the recording thin film diffuses into the intermediate layer or reacts with the elements of the intermediate layer, or at least a part of the elements of the intermediate layer is used for recording. It diffuses into the thin film or the reflective layer and thereby plays a part of the recording thin film.

The thickness of the intermediate layer is 3 nm or more and 400 nm.
Below, and in either the recording state or the erasing state, the reflectance of the recording thin film is close to the minimum value in the vicinity of the wavelength of the reading light, and the value is 2 in the other state.
It is preferable to set it to around 0% or more.

The reflective layer has a thermal conductivity of 2.0 W / cm.
When a material containing a high thermal conductivity material of deg or higher (for example, Au) as a main component is used, the thermal diffusivity becomes high, and even if a recording thin film that crystallizes at high speed is used, high power laser light is irradiated. When it is done, it surely becomes amorphous. In this case, a material having high thermal conductivity (for example, Al
₂ O ₃ , AlN, Si ₃ N ₄ , ZnS, or the like, or a material having a composition close to that, or a medium thermal conductivity of SiO ₂ (0.02 W / cm · deg or more, 0.1 W / c or more).
It is particularly preferable to use a material of m.deg. or less) and thin the intermediate layer. However, in order to increase the recording sensitivity, it is preferable to form the reflective layer with a material having a thermal conductivity lower than the above value.

The reflective layer may be arranged on the substrate side of the information recording thin film, or may be arranged on the opposite side of the information recording thin film from the substrate.

It is more preferable to form a protective layer (upper layer) made of an inorganic material usable for the protective layer on the side of the reflective layer opposite to the intermediate layer. A three-layer structure including the intermediate layer, the reflective layer, and the protective layer is stronger than the single-layer protective layer as a whole.

The above-mentioned substrate, recording thin film, protective layer, intermediate layer and reflective layer are formed by vacuum vapor deposition, vapor deposition in gas, sputtering, ion beam vapor deposition, ion plating, electron beam vapor deposition, injection molding, casting, spin coating. ,
Any method may be appropriately selected from methods such as plasma polymerization.

Most preferably, the recording thin film, the protective layer, the intermediate layer, the reflective layer, and the protective layer adjacent to the reflective layer are all formed by sputtering.

The above information recording thin film is dispersed in the above-mentioned oxide, fluoride, nitride, organic substance, or carbon or carbide as a material usable for the protective film by co-evaporation or co-sputtering. It is also possible to use a different form. By doing so, it may be possible to adjust the light absorption coefficient and increase the reproduction signal strength.

In this case, the mixing ratio is preferably such that the ratio of the number of atoms occupied by oxygen, fluorine, nitrogen and carbon in the thin film to the whole film is 40% or less, more preferably 20% or less.

By carrying out such a composite film formation,
Usually, the crystallization speed is lowered and the sensitivity is lowered, but the sensitivity is improved by forming a composite film with an organic substance.

Generally, when information is recorded by phase transition (phase change), it is preferable to crystallize the entire surface of the recording film in advance. However, when an organic substance is used as the substrate, the substrate is heated to a high temperature. I can't. Therefore, it is necessary to crystallize by another method.

Preferred crystallization methods in this case are, for example, irradiation with a laser beam focused so that the spot diameter is 2 μm or less, ultraviolet irradiation and heating with a xenon lamp or a mercury lamp, irradiation with a flash lamp light, and high irradiation. There are irradiation with light by a large laser light spot from an output gas laser or a high output semiconductor laser with an output of about 1 W, or a combination of heating and laser light irradiation.

When irradiating the information recording thin film with the laser beam focused to a spot diameter of 2 μm or less, it is often necessary to irradiate a plurality of times. Therefore, with a single laser beam, the thin film is repeatedly irradiated, which requires a long time. In order to avoid this, it is preferable to use a semiconductor laser array or to divide the gas laser beam into a plurality of beams and irradiate them at a plurality of locations at the same time. As a result, laser light irradiation can be performed many times by rotating the thin film once.

The light spots may be juxtaposed on the same recording track, but may be juxtaposed on two or more tracks. It is more preferable to irradiate on the track and between the tracks at the same time. The laser light power of each spot does not have to be the same.

When irradiating a single beam from a gas laser or a high-power semiconductor laser, a spot diameter (a diameter at a position where the light intensity becomes (1/2) in the case of a circular light spot, an elliptical light spot is used). If so, the efficiency is good if the major axis at the above position is 5 μm or more and 5 mm or less.

Crystallization only occurs on the recording track,
The tracks may remain amorphous. You may crystallize only between recording tracks.

For example, when a thin film containing Sb, Te, Ge and Cr as the main components is formed by rotary evaporation from a plurality of evaporation sources, immediately after the evaporation, Sb, Te, Ge and C are formed.
In many cases, the atoms of r are not well bonded. Also, when this thin film is formed by sputtering, the atomic arrangement is extremely disordered. Therefore, in such a case, first, it is preferable to irradiate the recording track with a laser beam having a high power density to heat the recording track so as to precipitate the high melting point component and, in some cases, selectively melt the thin film. Then, the recording track is irradiated with laser light having a low power density to crystallize the thin film. This has the advantage that the reflectance tends to be uniform over the entire circumference of the track.

Before irradiation with an energy beam such as a laser beam, the high melting point component may not exist in the information recording thin film, but by the crystallization treatment as described above, the high melting point component is contained in the thin film. It can be deposited or grown. As described above, the precipitated or grown high-melting point component is distributed almost independently in the form of particles or columns in the thin film, or the high-melting point component is continuously distributed in a porous form. In the former case, the high melting point component is distributed in the remaining component (usually the phase change component) of the thin film. In the latter case, the residual component is embedded in many pores of the high melting point component precipitate.

In the first manufacturing method, the high melting point component is likely to grow from the interfaces on both sides of the information recording thin film toward the inside thereof.

Recording (overwriting) information with a laser beam power-modulated between a power level for crystallization and a power level for making a state close to an amorphous state depends on how the thin film is crystallized. It is possible regardless.

In the first to sixth information recording thin films of the present invention, it is not always necessary to utilize the change between the amorphous state and the crystalline state for recording, and some atomic arrangement that hardly changes the shape of the film. It suffices if the change causes a change in optical properties. The precipitate of the high melting point component surely prevents the thin film from flowing and segregating.

For example, a change in crystal grain size or crystal form, a change between a crystal and a metastable state (π, γ, etc.) may be used.
It may be a change between an amorphous state and a crystalline state, or a part of both states may be mixed and not a completely amorphous state or a crystalline state, and the ratio thereof may be changed.

Further, between the recording thin film and at least one of the protective layer and the intermediate layer, some of atoms constituting these layers move due to diffusion, chemical reaction, etc. May be recorded, or information may be recorded by both atom movement and phase change.

The first information recording medium of the present invention is characterized by including any one of the first to sixth information recording thin films as a recording layer.

At least one interface of the information recording thin film is preferably in close contact with the protective layer. The protective layer can prevent an increase in noise due to the deformation of the thin film at the time of rewriting information.

The second information recording medium of the present invention is characterized by including any one of the first and sixth information recording thin films as a mask layer for super-resolution reading.

[0162]

In the first to fourth information recording thin films and the information recording medium using the same according to the present invention, since the element represented by the above B or X is added to Sb and Te, laser light or the like can be used. Precipitation of a high melting point component which is not melted by irradiation of recording / reproducing light is generated inside. Therefore, even if the remaining components other than the high-melting point component are melted by the light, the flow and segregation thereof are effectively prevented, and as a result, the flow and segregation when rewriting many times are effectively prevented.
When the deposited high melting point component is as large as the thickness of the information recording thin film, the deformation of the protective layer or the intermediate layer in contact with the thin film due to thermal expansion is suppressed and the space between the protective layer and the intermediate layer is maintained. The flow prevention effect of the thin film is enhanced.
As a result, the carrier-to-noise ratio (C / N) is stable and recording /
It is possible to perform rewriting or reading a number of times more than before while maintaining good reproduction characteristics.

When Sb, Te and the element represented by B or X coexist with the element represented by A, the amorphous state is stably maintained, and crystallization at the time of recording / erasing is performed at high speed. Like Also, the crystallization speed is optimally controlled, and the carrier-to-noise ratio and the erasure ratio are improved.

In the fifth and sixth information recording thin films and the information recording medium using the same according to the present invention, even if the recording / reproducing light such as the laser light is irradiated, the high melting point component contained therein is The precipitate does not melt. Therefore, even if the remaining components other than the high melting point component are melted by the light, their flow and segregation are effectively prevented. As a result, it becomes possible to rewrite or read a number of times more than before while maintaining good recording / reproducing characteristics.

Since the first information recording medium of the present invention comprises the first to sixth information recording thin films,
It is possible to perform rewriting or reading a number of times more than before while maintaining good reproduction characteristics.

In the second information recording medium of the present invention, when the light spot is irradiated on the mask layer made of any one of the first to sixth information recording thin films, the high temperature portion in the light spot has At least the remaining components other than the high melting point component melt. Real or imaginary part of the refractive index at high temperature (extinction coefficient)
Is smaller than that in the low temperature portion outside the light spot, so that the mask layer partially masks a part of the light spot diameter region, and it is as if the light spot diameter was reduced. As a result, a recording mark smaller than the light spot diameter can be read, that is, super-resolution reading can be performed.

In the third information recording medium of the present invention, when the light spot is irradiated on the reflecting layer made of any of the first to sixth information recording thin films, the high temperature portion within the diameter of the light spot is formed. The real part or extinction coefficient of the refractive index is smaller than that of the low temperature part outside the light spot. Therefore, the reflected light of the light irradiated to the high temperature portion of the reflective layer cannot be provided with sufficient contrast for reading the recording mark. As a result, as if the light spot diameter had decreased,
The recording marks formed at a pitch smaller than the light spot diameter can be read, that is, super-resolution reading can be performed.

Further, since a high melting point component having a melting point relatively higher than that of the phase change component is deposited, during super resolution reading,
Flow and segregation when the super-resolution readout film is melted by laser irradiation are effectively prevented. For this reason, it becomes possible to perform super-resolution reading a number of times more than in the past while maintaining good super-resolution reading characteristics.

When the average composition of the thin film for super-resolution reading is represented by the general formula (8), the element represented by A in the formula melts at a low temperature, so that the super-resolution reading is performed at a low temperature. This makes it possible to perform super-resolution reading on an optical disk such as a phase change optical disk other than the optical disk on which information is recorded by phase pits. When the element represented by B coexists with this, the compound of D and E or E
The compound of the element of E or the element of E becomes a high melting point component, and has an effect of preventing flow and segregation when the super-resolution readout film is melted. As F in the equation (12), for example, Tl
When C and N coexist, C / N can be increased.

In the super-resolution reading apparatus of the present invention, the laser power is increased only during the super-resolution reading, so that the deterioration of the super-resolution reading film can be prevented and the super-resolution reading can be performed many times. Further, when the laser period T, the linear velocity v, the spot diameter (λ / NA), and the pulse width x at the time of super-resolution reading satisfy the above relationships (9) and (10), It is possible to maintain the size of the mask area appropriately and improve the super-resolution readout characteristic. This device
Even when used in media other than the present invention, better results can be obtained than in the case where the super-resolution readout laser power is constant.

[0171]

EXAMPLES The present invention will be described in detail below with reference to examples.

Example 1 (Structure / Manufacturing Method) FIG. 3 shows a sectional structure of a disk-shaped information recording medium using the information recording thin film of the first example of the present invention. This medium was manufactured as follows.

First, a polycarbonate substrate 1 having a diameter of 13 cm and a thickness of 1.2 mm and having a tracking groove having a U-shaped cross section on its surface was formed. Next, the substrate 1 was placed in a magnetron sputtering apparatus in order to sequentially form thin films on the substrate 1. This apparatus has a plurality of targets and is capable of sequentially forming laminated films.
In addition, the thickness and the reproducibility of the formed film are excellent.

First, a protective layer 2 made of a (ZnS) ₈₀ (SiO ₂ ) ₂₀ film was formed on the substrate 1 by a magnetron sputtering device so as to have a film thickness of about 125 nm. Then, Cr ₄ T, which is a high melting point component, is formed on the protective layer 2.
e ₅ film was formed to an average thickness of 3nm (not shown) like _{islands, Sb 16 Te 55 Ge 16 Cr} 13 thereon, i.e. _{((Ge 2 Sb 2 Te 5} ) 7 (Cr 4 Te 5) The recording film 3 having the composition of ₃ ) was formed to a film thickness of about 30 nm. At this time, Cr ₄
The rotating co-sputtering method using a Te ₅ target and a Ge ₂ Sb ₂ Te ₅ target was used. The island-shaped Cr ₄ Te ₅ film has a size of about 2 to 20 nm, and the island pitch is (size) ×
(1.5-10) is desirable.

The Cr ₄ Te ₅ film does not necessarily have to be formed. In that case, the high-melting-point components that precipitate in the recording film 3 are only those that occur during the initial crystallization described below.

Next, on the recording film 3, (ZnS) ₈₀ (Si
After forming the intermediate layer 4 consisting of O ₂ ) ₂₀ film to a film thickness of about 25 nm, Al _{97 is} formed on the intermediate layer 4 in the same sputtering apparatus.
The reflective layer 5 made of a Ti ₃ film was formed to a film thickness of 80 nm. Thus, the first disc member was obtained.

On the other hand, a second disk member having the same structure as the first disk member was obtained by the completely same method. The second disc member has a diameter of 13 cm and a thickness of 1.2.
The film thickness is about 125 nm, which is sequentially stacked on the substrate 1'of mm.
Of the (ZnS) ₈₀ (SiO ₂ ) ₂₀ film,
Cr ₄ Te ₅ film (not shown) with an average film thickness of 3 nm, film thickness of about 3
0 nm of Sb ₁₆ Te ₅₅ Ge ₁₆ Cr ₁₃ , ie, ((Ge
₂ Sb ₂ Te ₅ ) ₇ (Cr ₄ Te ₅ ) ₃ ) recording film 3 ′, intermediate layer 4 ′ made of (ZnS) ₈₀ (SiO ₂ ) ₂₀ film having a film thickness of about 25 nm, and Al _{97 having a} film thickness of 80 nm. Ti ₃ and a reflective layer 5 'formed of film.

Thereafter, the reflective layers 5 and 5'of the first and second disk members are bonded to each other through the vinyl chloride-vinyl acetate hot melt adhesive layer 6 to record the disk-shaped information shown in FIG. The medium was obtained.

In this medium, if the entire surfaces of the reflective layers 5 and 5'are adhered, the number of rewritable times can be increased as compared with the case where the entire surfaces are not adhered, and the recording areas of the reflective layers 5 and 5'can be handled. The recording sensitivity was slightly higher when the adhesive was not applied to the areas to be treated than when the adhesive was applied to the areas as well.

(Initial Crystallization) The recording films 3, 3'of the medium manufactured as described above were subjected to initial crystallization as follows. Since the same applies to the recording film 3 ', only the recording film 3 will be described below.

The medium is rotated at 1800 rpm, the laser light power of the semiconductor laser (wavelength 830 nm) is maintained at a level (about 1 mW) at which recording is not performed, and the laser light has a numerical aperture (NA) of 0. The light was condensed by the lens 55 and was irradiated onto the recording film 3 through the substrate 1. The reflected light from the recording film 3 is detected to perform tracking so that the center of the laser light spot always coincides with the center of the tracking groove of the substrate 1, and the focal point of the laser light comes to the recording film 3. The recording head was driven while performing automatic focusing.

First, for initial crystallization, powers of 12 mW, 13 mW, and 14 m were recorded on the same recording track of the recording film 5.
W continuous laser light was irradiated 500 times each. Finally, a continuous (DC) laser beam with a power of 15 mW is set to 1000
Irradiated twice. Irradiation time of each time (light spot passage time)
Is about 0.1 μsec.

Then, a continuous laser beam having a power of 8 mW was changed to 5 times.
Irradiated 00 times. The irradiation time (light spot passage time) at each time is about 0.1 μsec. The laser light power at this time may be in the range of 5 to 9 mW.

Of the two types of laser light irradiation, the irradiation with the lower power (8 mW) may be omitted.

As described above, when the laser beams having different powers are irradiated, the initial crystallization can be sufficiently performed.

Irradiation of these laser beams is performed by a semiconductor laser
If an array is used, or a light beam from a gas laser is divided into a plurality of beams, or the spot shape of the light beam from a high-power gas laser or a semiconductor laser is made into an ellipse elongated in the radial direction of the medium. , And more preferably. This makes it possible to complete the initial crystallization by rotating the medium a few times.

When a plurality of laser light spots are used, if the laser light spots are not arranged on the same recording track but the positions are gradually shifted in the radial direction of the medium, a wide range can be obtained by one irradiation. Can be initialized,
It has the effect of reducing the remaining loss.

Next, a continuous laser beam of 12 mW having a circular spot (high power light for recording) is irradiated once (irradiation time:
The recording film 5 was made amorphous by irradiating a pulsed laser light (high power light for recording) with a power of 18 mW every about 0.1 μsec) to form recording points. After that, set the recording point to 8
It was investigated how many times it was necessary to irradiate continuous laser light of 8 mW in order to irradiate and crystallize continuous laser light of mW (low power light for initial crystallization).

As a result, the number of times of continuous laser light irradiation of 8 mW required for crystallization decreased as the number of times of irradiation of continuous laser light of 12 mW increased to 5 times. That is, it was found that crystallization was more likely to occur as the number of irradiations increased. This is because a large number of fine crystals of Cr ₄ Te ₅ which is a high melting point component are precipitated in the recording film 5 by irradiation with a continuous laser beam of 12 mW, and the rest (phase change portion).
It is presumed that the composition of s was close to the composition of Ge ₂ Sb ₂ Te ₅ capable of high-speed crystallization.

The melting point of Cr ₄ Te ₅ is 1252 ° C. and that of Ge ₂ Sb ₂ Te ₅ is 630 ° C.

(Recording / Erasing) Next, while performing tracking and automatic focusing on the recording region of the recording film 3 whose initial crystallization is completed as described above, in the same manner as described above,
The power of the recording laser beam is set to an intermediate power level (8 mW) and a high power level (18 mW) according to the information signal to be recorded.
The recording of information was carried out by changing the recording speed with that of W). After passing the portion to be recorded, the laser light power was lowered to the low power level (1 mW) of the reproduction (reading) laser light. The amorphous point or a portion close to it which is formed in the recording area by the recording laser beam becomes the recording point.

The power ratio between the high level and the intermediate level of the recording laser light is particularly preferably in the range of 1: 0.3 to 1: 0.8. In addition to this, another power level may be set for each short time.

In such a recording method, if new information is directly recorded in a portion where information has already been recorded, it can be rewritten with new information. That is, overwriting with a single circular light spot is possible.

However, the power (eg, 9 m) close to the intermediate power level (8 mW) of the power-modulated recording laser beam at the first one or more rotations at the time of rewriting.
W) continuous light is applied to erase the recorded information, and then, in the next one rotation, a low power level (1 mW) of the reproducing (reading) laser light and a high power level of the recording laser light. The recording may be performed by irradiating the laser light whose power is modulated according to the information signal between (18 mW) or between the intermediate power level (8 mW) and the high power level (18 mW) of the recording laser light. . In this way, if the information is erased and then recorded, the previously written information remains less and the high carrier-to-noise ratio (C / N) is obtained.

In the case of rewriting after erasing in this way, the power level of the continuous laser light to be irradiated first is 0.4 to 1 when the high level (18 mW) of the recording laser light is 1. It is preferable to set it in the range of 1. This is because good rewriting can be performed within this range.

This method is effective not only for the recording film of the present invention but also for other recording films.

In the information recording medium of this example, recording / erasing could be repeated 10 ⁵ or more times under severe conditions in which the power of the laser beam was increased by 15% from the optimum value.
Also, the C / N of the reproduced signal when the 2 MHz signal is recorded
Was about 50 dB, which was extremely good.

In the recording film 3 of this embodiment, the number of rewritable times can be set to 10 ⁵ or more because the high melting point component deposited in the recording film 3 causes the residual component (phase change portion) of the recording film 3 to be rewritten. It is understood that the flow and segregation of) are prevented.

The ZnS- formed on the recording film 3
When the intermediate layer 4 of SiO ₂ and the reflective layer 5 of Al—Ti were omitted, a slight increase in noise occurred after recording and erasing by an order of magnitude less than the above.

(Relationship with Te content y) The above (Ge ₂
In the recording film 3 made of Sb ₂ Te ₅ ) ₇ (Cr ₄ Te ₅ ) ₃ , the Te content y is changed while keeping the relative ratio of other elements constant, and it is necessary to erase the recorded information. The irradiation time of laser light and the laser light power are set to 15
The change in the carrier-to-noise ratio (C / N) of the reproduced signal was measured after rewriting 10 ⁵ times under the strict condition of increasing%. As a result, the following data were obtained.

[0201] From this result, it can be seen that in the range where Te content y is in the range of 25 ≦ y ≦ 75, the characteristic change due to a large number of rewritings of 10 ⁵ is small.

(Relationship with composition of elements other than Cr) The composition was changed on a straight line connecting the Ge ₆₅ Te ₂₅ Cr ₁₀ and Sb ₃₀ Te ₆₀ Cr ₁₀ in the triangular phase diagram of FIG. 6 with the Cr content being constant. The crystallization temperature of the unrecorded portion when the temperature was raised at a constant rate and the change in the bit error rate when left for 1000 hours at 80 ° C. and 95% relative humidity were measured. As a result, the following data were obtained.

Crystallization temperature Sb ₃₀ Te ₆₀ Cr ₁₀ 120 ° C Sb ₂₈ Te ₅₈ Ge ₄ Cr ₁₀ 150 ° C Sb ₂₅ Te ₅₅ Ge ₁₀ Cr ₁₀ 160 ° C Sb ₂₂ Te ₅₁ Ge ₁₇ Cr ₁₀ 170 ° C Sb ₁₂ Te ₃₈ Ge ₄₀ Cr ₁₀ 190 ° C Sb ₂ Te ₂₈ Ge ₆₀ Cr ₁₀ 220 ° C Change in bit error rate Sb ₃₀ Te ₆₀ Cr ₁₀ 2 times Sb ₂₈ Te ₅₈ Ge ₄ Cr ₁₀ 2 times Sb ₂₅ Te ₅₅ Ge ₁₀ Cr ₁₀ 2 times Sb ₂₂ Te ₅₁ Ge ₁₇ Cr ₁₀ 2.5 times Sb ₁₂ Te ₃₈ Ge ₄₀ Cr ₁₀ 4 times Sb ₂ Te ₂₃ Ge ₆₀ Cr ₁₀ 5 times As a result, even if the composition other than Cr changes, It can be seen that a sufficiently high crystallization temperature was obtained and the change in bit error rate was not so large even under high temperature and high humidity.

Sb ₄₅ Te ₄₅ Cr ₁₀ and G in the triangular phase diagram of FIG.
The composition was changed on a straight line with a constant Cr content connecting e ₁₈ Te ₇₂ Cr ₁₀ and the temperature was raised at a constant rate, and the temperature was kept at 80 ° C. and relative humidity of 95% for 1000 hours. The change in bit error rate was measured. As a result, the following data were obtained.

Crystallization temperature Sb ₂ Te ₇₁ Ge ₁₇ Cr ₁₀ 210 ° C Sb ₄ Te ₆₉ Ge ₁₇ Cr ₁₀ 200 ° C Sb ₈ Te ₆₇ Ge ₁₅ Cr ₁₀ 190 ° C Sb ₂₃ Te ₅₈ Ge ₉ Cr ₁₀ 170 ° C Sb ₃₀ Te ₅₄ Ge ₆ Cr ₁₀ 150 ° C Sb ₃₈ Te ₄₉ Ge ₃ Cr ₁₀ 130 ° C Sb ₄₁ Te ₄₇ Ge ₂ Cr ₁₀ 110 ° C Change in bit error rate Sb ₂ Te ₇₁ Ge ₁₇ Cr ₁₀ 5 times Sb ₄ Te ₆₉ Ge ₁₇ Cr ₁₀ 3 times Sb ₈ Te ₆₇ Ge ₁₅ Cr ₁₀ 2 times Sb ₂₃ Te ₅₈ Ge ₉ Cr ₁₀ 1.5 times Sb ₃₀ Te ₅₄ Ge ₆ Cr ₁₀ 1.5 times Sb ₃₈ Te ₄₉ Ge ₃ Cr ₁₀ 1 times Sb ₄₁ Te ₄₇ Ge ₂ Cr ₁₀ 1 times As a result, even if the composition other than Cr changes, a sufficiently high crystallization temperature can be obtained, and the bit error rate changes greatly even under high temperature and high humidity. Nothing It can be seen.

Ratio (p of Ge content p and Sb content x)
/ X) was changed and the change in bit error rate when the sample was placed in a temperature of 80 ° C. and a relative humidity of 95% for 1000 hours was measured. The following results were obtained.

[0207] From this result, when the ratio (p / x) of the Ge content p and the Sb content x is in the range of 0.25 ≦ (p / x) ≦ 1.0, the bit error rate changes. It turns out that it is particularly small.

The balance of Cr ₄ Te ₅ is Sb vs. Te vs. Ge.
When the content of Cr ₄ Te ₅ is changed while keeping the ratio of the content x, y, p of x: y: p = 2: 5: 2, the power of the laser light is increased by 15% from the optimum value. 10 under severe conditions
^When the C / N of the reproduced signal after rewriting ⁵ times was measured, the following results were obtained regarding the content q of Cr.

Reproduction signal after rewriting 10 ⁵ times C / N q = 0 42 dB q = 3 46 dB q = 4 48 dB q = 10 50 dB q = 20 50 dB q = 34 48 dB When the content q of Cr is changed, The "erase ratio" of the reproduced signal after rewriting 10 ⁵ times under a severe condition in which the power of 1 was increased by 15% from the optimum value changed as follows.

Here, the "erase ratio" is the ratio of the signal before and after the overwriting when another signal having a different frequency is overwritten on the already recorded signal in dB.

[0211] From this result, it can be seen that the erasing ratio decreases as the Cr content q increases.

In a system containing 10% of Cr as described above, when the Te content y was kept constant and the Sb content x was changed, the power of the laser beam was increased by 15% from the optimum value under severe conditions. The C / N of the reproduced signal after rewriting 10 ⁵ times is
It changed as follows.

C / N x = 38 48 dB x = 30 50 dB x = 15 50 dB x = 8 50 dB x = 4 48 dB x = 2 46 dB x = 0 45 dB C / N x = 38 48 dB x = 30 50 dB x = 15 45 dB of the reproduced signal after rewriting 10 ⁵ times When the amount x is 2% or more,
It can be seen that a good C / N of the reproduced signal can be obtained.

From the above, Sb ₁₆ Te ₅₅ Ge of this embodiment
₁₆ Cr ₁₃ , that is, (Ge ₂ Sb ₂ Te ₅ ) ₇ (Cr ₄ T
In the recording film ₃ of e ₅ ) ₃ , the change in bit error rate when left for 1000 hours in a temperature of 80 ° C. and a relative humidity of 95% was less than twice, and the power of laser light was made 15% higher than the optimum value. C of reproduced signal after rewriting 10 ⁵ times under severe conditions
/ N and erasure ratio are 50 dB or more and 28, respectively.
It was found that it was at least dB, rewritable at least 2 × 10 ⁵ times, and had extremely excellent characteristics.

(Other example 1 of additive element) Instead of part or all of Cr, Ag, Cu, Ba, Co, La, Ni,
Even if at least one of Pt, Si and Sr and the lanthanoid element is added, characteristics similar to the above case can be obtained. For example, when Cu was added (Cu addition amount: q), the following data was obtained.

[0216] From this result, it is understood that the rewritable number remarkably increases when Cu is added.

(Other Example 2 of Additive Element) In addition to Cr, it is preferable to add Tl (thallium) which has an effect of accelerating erasing and increasing C / N. In this case, the C / N is further increased and the number of rewritable times is increased as compared with the case where only Cr is added, which is more preferable. However, it is preferable that the sum of the added amounts of Cr and Tl is 30 atomic% or less, because the amount of the remaining erasure does not increase. If the sum of the added amounts of Cr and Tl is 0.5% or more and 20 atomic% or less,
More preferable.

For example, Ge _8.2 Sb _16.4 Te _64.4 Tl _0.5
With the Cr _10.5 recording film, C / N of 50 dB and rewritable number of times of 2 × 10 ⁵ were obtained.

Similar characteristics can be obtained by adding at least one halogen element instead of part or all of Tl.

When N (nitrogen) is added instead of Tl,
The number of rewritable times is further improved. However, if the amount is too large, the reproduction signal level decreases.

(Other Example 3 of Additive Element) In addition to this, Tl
Substituting Se for thallium and adding Se in an amount of 1 atomic% or more and 10 atomic% or less while keeping the relative proportions of other elements constant, has the effect of improving the oxidation resistance.

(Another Example of Phase Change Component) A part of Ge ₂ Sb ₂ Te ₅ , which is the phase change component of this embodiment, is replaced with GeSb ₂ T.
e ₄ , GeSb ₄ Te ₇ , In ₃ SbTe ₂ , In ₃₅ Sb ₃₂
Even if it is replaced with at least one of Te ₃₃ , In ₃₁ Sb ₂₆ Te ₄₃ , and a composition close to these, or if part of Ge is replaced with In, characteristics close to this can be obtained.

(Other Examples of High Melting Point Component) The high melting point component to be precipitated may be a compound, a simple element or an alloy. A part or all of Cr ₄ Te ₅ , which is the high melting point component of this embodiment, is replaced with LaTe ₂ , La ₂ Te ₃ , La ₃ Te ₄ , LaTe,
La ₂ Te ₅ , La ₄ Te ₇ , LaTe ₃ , La ₃ Te, La
₂ Sb, La ₃ Sb ₂ , LaSb, LaSb ₂ , La ₃ G
e, La ₅ Ge ₃ , La ₄ Ge ₃ , La ₅ Ge ₄ , LaGe,
La ₃ Ge ₅ , Ag ₂ Te, Cr ₅ Te ₈ , Cr ₂ Te ₃ , C
rSb, Cr ₃ Ge, Cr ₅ Ge ₃ , Cr ₁₁ Ge ₈ , CrG
e, Cr ₁₁ Ge ₁₉ , PtTe ₂ , Pt ₄ Te ₅ , Pt ₅ Te
₄ , Pt ₄ Sb, Pt ₃ Sb ₂ , PtSb, Pt ₃ Ge, P
t ₂ Ge, Pt ₃ Ge ₂ , PtGe, Pt ₂ Ge ₃ , PtG
e ₃ , NiTe, NiTe ₀ . ₈₅ , NiSb, Ni ₃ G
e, Ni ₅ Ge ₂ , Ni ₅ Ge ₃ , NiGe, CoTe ₂ ,
CoSb ₂ , CoSb ₃ , Co ₅ Ge ₂ , Co ₅ Ge ₃ , Co
Ge, Co ₅ Ge ₇ , CoGe ₂ , Si ₂ Te ₃ , SiS
b, SiGe, CeTe, Ce ₃ Te ₄ , Ce ₂ Te ₃ , C
e ₄ Te ₇ , CeTe ₂ , CeTe ₃ , Ce ₂ Sb, Ce ₅ S
b ₃ , Ce ₄ Sb ₅ , CeSb, CeSb ₂ , Ce ₃ Ge,
Ce ₅ Ge ₃ , Ce ₄ Ge ₃ , Ce ₅ Ge ₄ , CeGe, Ce
₃ Ge ₅ , Ce ₅ Si ₃ , Ce ₃ Si ₂ , Ce ₅ Si ₄ , CeS
i, Ce ₃ Si ₅ , CeSi ₂ , Cr ₃ Si, Cr ₅ Si ₃ ,
CrSi, CrSi ₃ , CrSi ₂ , Co ₃ Si, CoS
i, CoSi ₂ , NiSi ₂ , NiSi, Ni ₃ Si ₂ , N
i ₂ Si, Ni ₅ Si ₂ , Ni ₃ Si, Pt ₅ Si ₂ , Pt ₂
Si, PtSi, LaSi ₂ , Ag ₃ In, Ag ₂ In,
Bi ₂ Ce, BiCe, Bi ₃ Ce ₄ , Bi ₃ Ce ₅ , Bi
Ce ₂ , Cd ₁₁ Ce, Cd ₆ Ce, Cd ₅₈ Ce ₁₃ , Cd ₃
Ce, Cd ₂ Ce, CdCe, Ce ₃ In, Ce ₂ In,
Ce _{1 + x} In, Ce ₃ In ₅ , CeIn ₂ , CeIn ₃ , C
e ₂ Pb, CePb, CePb ₃ , Ce ₃ Sn, Ce ₅ Sn
₃ , Ce ₅ Sn ₄ , Ce ₁₁ Sn ₁₀ , Ce ₃ Sn ₅ , Ce ₃ Sn
₇ , Ce ₂ Sn ₅ , CeSn ₃ , CeZn, CeZn ₂ , C
_{eZn 3, Ce 3 Zn 11,} Ce 13 Zn 58, CeZn 5, C
_{e 3 Zn 22, Ce 2 Zn} 17, CeZn 11, Cd 21 Co 5,
CoGa, CoGa ₃ , CoSn, Cr ₃ Ga, CrG
a, Cr ₅ Ga ₆ , CrGa ₄ , Cu ₉ Ga ₄ , Cu ₃ Sn,
Cu ₃ Zn, Bi ₂ La, BiLa, Bi ₃ La ₄ , Bi ₃
La ₅ , BiLa ₂ , Cd ₁₁ La, Cd ₁₇ La ₂ , Cd ₉ L
a ₂ , Cd ₂ La, CdLa, Ga ₆ La, Ga ₂ La, G
aLa, Ga ₃ La ₅ , GaLa ₃ , In ₃ La, In ₂ L
a, In ₅ La ₃ , In _x La, InLa, InLa ₂ , I
nLa ₃ , La ₅ Pb ₃ , La ₄ Pb ₃ , La ₁₁ Pb ₁₀ , L
a ₃ Pb ₄ , La ₅ Pb ₄ , LaPb ₂ , LaPb ₃ , LaZ
n, LaZn ₂ , LaZn ₄ , LaZn ₅ , La ₃ Zn ₂₂ ,
La ₂ Zn ₁₇ , LaZn ₁₁ , LaZn ₁₃ , NiBi, G
a ₃ Ni ₂ , GaNi, Ga ₂ Ni ₃ , Ga ₃ Ni ₅ , GaN
i ₃ , Ni ₃ Sn, Ni ₃ Sn ₂ , Ni ₃ Sn ₄ , NiZn,
Ni ₅ Zn ₂₁ , PtBi, PtBi ₂ , PtBi ₃ , Pt
Cd ₂ , Pt ₂ Cd ₉ , Ga ₇ Pt ₃ , Ga ₂ Pt, Ga ₃ P
t ₂ , GaPt, Ga ₃ Pt ₅ , GaPt ₂ , GaPt ₃ ,
In ₇ Pt ₃ , In ₂ Pt, In ₃ Pt ₂ , InPt, In ₅
Pt ₆ , In ₂ Pt ₃ , InPt ₂ , InPt ₃ , Pt ₃ P
b, PtPb, Pt ₂ Pb ₃ , Pt ₃ Sn, PtSn, P
t ₂ Sn ₃ , PtSn ₂ , PtSn ₄ , Pt ₃ Zn, PtZ
n ₂ , AlS, Al ₂ S ₃ , BaS, BaC ₂ , CdS, C
o ₄ S ₃ , Co ₉ S ₈ , CoS, CoO, Co ₂ O ₄ , Co ₂
O ₃ , Cr ₂ O ₃ , Cr ₃ O ₄ , CrO, CrS, CrN,
Cr ₂ N, Cr ₂₃ C ₆₃ , Cr ₇ C ₃ , Cr ₃ C ₂ , Cu ₂ S,
Cu ₉ S ₅ , CuO, Cu ₂ O, In ₄ S ₅ , In ₃ S ₄ , L
a ₂ S ₃ , La ₂ O ₃ , Mo ₂ C, MoC, Mn ₂₃ C ₆ , Mn
₄ C, Mn ₇ C ₃ , NiO, SiS ₂ , SiO ₂ , Si
₃ N ₄ , a high melting point oxide of the constituent elements of the high melting point component, Cu ₂ Te, CuTe, Cu ₃ Sb, Mn ₂ Sb,
MnTe, MnTe ₂ , Mn ₅ Ge ₃ , Mn _3.25 Ge, M
n ₅ Ge, Mn ₃ Ge ₂ , Ge ₃ W, Te ₂ W, AlSb,
Al ₂ Te ₃ , Fe ₂ Ge, FeGe ₂ , FeSb ₂ , Mo ₃
Sb ₇ , Mo ₃ Te ₄ , MoTe ₂ , PbTe, GePd ₂ ,
Ge ₂ Pd ₅ , Ge ₉ Pd ₂₅ , GePd ₅ , Pd ₃ Sb, Pd
₅ Sb ₃ , PdSb, SnTe, Ti ₅ Ge ₃ , Ge
₃₁ V ₁₇ , Ge ₈ V ₁₁ , Ge ₃ V ₅ , GeV ₃ , V ₅ Te ₄ , V
₃ Te ₄ , ZnTe, Ag ₂ Se, Cu ₂ Se, Al ₂ S
e ₃ , InAs, CoSe, Mn ₃ In, Ni ₃ In, N
B such as iIn, Ni ₂ In ₃ , Ni ₃ In ₇ , PbSe, etc.
Even if it is replaced with at least one of a high melting point compound containing a group of elements, a compound having a composition close to that, or a mixed composition or a compound of three or more elements close to the mixed composition,
Similar results are obtained.

Of these, LaSb, CrSb, C
oSb, Cr ₃ Te ₄ , LaTe ₃ , Cr ₄ Te ₅ , Cr ₂ T
e ₃ , Cr ₃ Te ₄ , CoTe, Co ₃ Te ₄ , Cu ₂ Te,
CuTe, Cu ₃ Sb, MnTe, MnTe ₂ , Mn ₂ S
At least one of b is particularly preferred. This is because the recording / erasing characteristics are stabilized by a small number of initial crystallizations.

(Amount of High Melting Point Component Content) The content of oxides, sulfides, nitrides, and carbides contained in the high melting point component precipitates is preferably less than 40 atom% of the high melting point component. It is particularly preferable that the amount is less than 10 atomic%. When the content of these components is large, there is a problem that the difference in complex refractive index from the phase change component cannot be reduced or oxygen or the like diffuses into the phase change component to deteriorate recording / reading characteristics.

In the many compounds described above as examples of the high melting point component, the interface reflectance of the recording film 3 changed as follows when the content v ′ of the transition metal element was different.

[0227] From this result, it is found that the interface reflectance increases as the content v ′ of the transition metal element increases.

(Content of High Melting Point Compound in Recording Thin Film)
The content a ′ of the high melting point compound contained in the recording thin film is
Expressed as a ratio (atomic%) of the sum of the number of atoms of the constituent elements of the high melting point compound to the sum of the numbers of atoms of all the constituent elements of the high melting point component, and when the content a ′ is changed, the number of rewritable times and Under severe conditions with laser power increased by 15% 1
The erase ratio after rewriting 0 ⁵ times changed as follows.
This change in C / N is mainly due to the change in C level.

Number of rewritable times a ′ = 5 atomic% 4 × 10 ⁴ times a ′ = 10 atomic% 1 × 10 ⁵ times a ′ = 20 atomic% 1.5 × 10 ⁵ times a ′ = 30 atomic% 2 × 10 Erasure ratio after rewriting ⁵ times 10 ⁵ times a '= 30 atomic% 30 dB a' = 40 atomic% 30 dB a '= 50 atomic% 25 dB a' = 60 atomic% 23 dB It has been found that when the melting point compound content a ′ increases, the number of rewritable times increases, but when the melting point compound content a ′ increases excessively, the erase ratio after 10 ⁵ times of rewriting decreases. Therefore, 10 atomic% ≦ a ′ ≦ 5
It has been found that a range of 0 atom% is preferred.

(Complex Refractive Index of High Melting Point Component) The real part n ₁ and the imaginary part (extinction coefficient) k ₁ of the complex refractive index of the high melting point component are their values n ₂ in the crystallized state of the phase change component, When the difference from k ₂ is Δn = (| n ₁ −n ₂ | / n ₁ ) × 100 and Δk = (| k ₁ −k ₂ | / k ₁ ) × 100, the power of the laser light is lower than the optimum value. After rewriting 10 5 times under the severe condition of 15% higher, the C / N of the reproduced signal changed as follows. This change in C / N is mainly due to the change in N level.

C / N Δk, Δn = 10% 49 dB Δk, Δn = 20% 48 dB Δk, Δn = 30% 47 dB Δk, Δn = 40% 46 dB Δk, Δn = 50% 43 dB of the reproduced signal after rewriting 10 ⁵ times From this result, it was found that it is preferable that the differences Δn and Δk between the real part and the imaginary part (extinction coefficient) of the complex refractive index are smaller.

(Structure / Dimension of Precipitate of High Melting Point Component) The above-mentioned high melting point component such as Cr ₄ Te ₅ is shown in FIG. 1 (a) (b).
It is deposited inside the recording film 3 in a form as shown in (c).

In FIG. 1A, a large number of granular precipitates of the high melting point component 3b are distributed in the recording film 3 in an independent state. The portion other than the high melting point component 3b of the recording film 3, that is, the remaining component is the phase change component 3a. The length of the high melting point component 3b in the film surface direction and the length in the direction perpendicular to the film surface are substantially the same, or even if they are different, the difference in length is small. Here, some of the precipitates of the high melting point component 3b are in contact with one of the interfaces of the recording film 3, and some of them are not in contact with any of the interfaces.

In the medium of FIG. 3, the high melting point component 3b is Cr ₄
Te ₅ and the phase change component 3a are made of Ge ₂ Sb ₂ Te ₅ .

In FIG. 1B, a large number of precipitates of the high melting point component 3b are independently distributed in the recording film 3 as in the case of FIG. 1A. However, the difference is that the high melting point component 3b is deposited in a columnar shape. That is, the length of the high melting point component 3b in the direction perpendicular to the film surface is larger than the length in the film surface direction, and the cross section perpendicular to the film surface is columnar. Some of the deposits of the high melting point component 3b are in contact with one interface of the recording film 3, and others are in contact with the other interface of the recording film 3. Here, nothing is in contact with both interfaces.

In FIG. 1C, a large number of precipitates of the high melting point component 3b are connected to each other and distributed in the recording film 3 in an integrated state. That is, the high melting point component 3b is deposited in a porous form, and the phase change component 3a is embedded in the numerous small holes of the high melting point component 3b. The porous high melting point component 3b is in contact with both interfaces of the recording film 3. The phase change components 3a are distributed in the recording film 3 independently of each other. This state corresponds to the case in which the phase change component 3a and the high melting point component 3b are replaced in the case of FIG. 1 (a).

Depending on the film forming conditions and the initial crystallization conditions, any of the states of (a) to (c) of FIG. 1 appears, but in any state, the high melting point component 3b causes the recording film 3 to be formed. The phase change component 3a is prevented from flowing and segregating when heated and melted, and as a result, the number of rewritable times is improved.

In the present invention, the "maximum external dimension d '", "height h and h'" of the precipitate of the high melting point component 3b,
"Center distance", "Maximum hole size" and "Maximum wall thickness"
Shall be defined as follows, respectively.

When the precipitates of the high melting point component 3b are independently distributed as in (a) and (b) of FIG.
As shown in (b), a cross section parallel to the film surface of the recording film 3 (hereinafter, referred to as "(1/3)" of the film thickness T of the recording film 3 at a position separated from one of the interfaces of the recording film 3 (Referred to as the first reference cross section), the length of the precipitate of each high melting point component 3b in that cross section is measured. Then, the maximum value of the length measured in any direction is defined as "maximum external dimension d '".

The "maximum external dimension d '" specifically means the diameter of the precipitate when the shape in the first reference cross section is circular or close to a circle, as shown in FIG. When it is close to a shape or an ellipse, it means the major axis of the precipitate, and when it is polygonal, it means the length of the longest diagonal of the precipitate.

The “height h” is a cross section perpendicular to the film surface of the recording film 3 (hereinafter referred to as the second reference cross section), and in that cross section, the film of the recording film 3 of the precipitate of each high melting point component 3b is formed. Measure the length perpendicular to the plane. The length thus obtained is defined as "height h" of the precipitate of the high melting point component 3b.

As shown in FIG. 4 (a), this "height h" means that the granular precipitates of the high melting point component 3b are distributed,
As shown in FIG. 4B, it is applied to the case where the columnar precipitate of the high melting point component 3b is distributed in contact with both interfaces of the recording film 3.

The "height h '" and "height h""have the same concept as the above-mentioned" height h ", but as shown in FIG. 4 (c), a columnar precipitate of the high melting point component 3b Is distributed only in contact with one of the interfaces of the recording film 3 and is not applied in the case of being in contact with the interface.

As shown in FIG. 2A, the "center-to-center distance i" means the average value of the distances between the centers of the precipitates of two adjacent high melting point components 3b in the first reference cross section. .

The "maximum pore size p" is applied when the porous high melting point component 3b is precipitated as shown in FIG. 1 (c), and is the high melting point component in the first reference cross section. It means the maximum value of the size of each hole in the precipitate of 3b.

This "maximum hole size p""specifically means the diameter of the hole when the hole shape in the first reference cross section is circular or nearly circular as shown in FIG. Or, when it is close to an ellipse, it means the major axis of the hole, and when it is polygonal, it means the length of the longest diagonal of the hole.

Like the "maximum pore size p"",the" maximum wall thickness w "is applied when the porous high melting point component 3b is deposited, and as shown in FIG. In one standard cross section, it means the maximum value of the wall thickness between two adjacent holes of the precipitate of the high melting point component 3b.

(Relationship with Size of Precipitate of High Melting Point Component) When the "maximum external dimension d '" of the precipitate of high melting point component 3b is different, the number of rewritable times and the power of laser light are 15% from the optimum value. The C / N of the reproduced signal after rewriting 10 ⁵ times under the raised strict condition changed as follows. This C /
The change in N is mainly due to the change in N level.

Number of rewritable times d ′ = 50 nm 2 × 10 ⁵ times d ′ = 30 nm 2 × 10 ⁵ times d ′ = 10 nm 2 × 10 ⁵ times d ′ = 5 nm 1.5 × 10 ⁵ times d ′ = 1 nm 4 × 10 ⁴ times 10 ⁵ times C / N of reproduced signal after rewriting d = 80 nm 46 dB d ′ = 50 nm 47 dB d ′ = 20 nm 49 dB d ′ = 15 nm 49 dB d ′ = 5 nm 50 dB From this result, 5 nm ≦ d ′ ≦ 50 nm It has been found that the range is preferred.

As shown in FIG. 4B, the columnar high melting point component 3
When b was deposited from the interfaces on both sides of the recording film 3, the rewritable count changed as follows when the "height h" of the deposit was different.

[0251] From this result, it was found that the range of 10 nm ≦ h is preferable.

As shown in FIG. 4C, the columnar high melting point component 3
When b was deposited from the interface on one side of the recording film 3, the rewritable count changed as follows when the “height h ′” of the deposit was different.

[0253] When the columnar high melting point component 3b was not in contact with the interface of the recording film 3 and the "height h""of the precipitate was different, the rewritable count changed as follows.

[0254] From this result, it was found that the range of 5 nm ≦ h ′ and h ″ is preferable.

When the "center-to-center distance i" is different, the number of rewritable times and the C of the reproduced signal after rewriting 10 ⁵ times under severe conditions in which the power of the laser beam is 15% higher than the optimum value
/ N changed as follows. This change in C / N is mainly due to the change in C level.

Number of rewritable times i = 120 nm 8 × 10 ⁴ times i = 90 nm 1.5 × 10 ⁵ times i = 70 nm 1.8 × 10 ⁵ times i = 60 nm 2 × 10 ⁵ times i = 40 nm 2 × 10 ⁵ times i = 15 nm 2 × 10 ⁵ times 10 ⁵ times C / N of reproduced signal after rewriting i = 70 nm 50 dB i = 40 nm 50 dB i = 30 nm 49 dB i = 20 nm 46 dB i = 15 nm 45 dB i = 10 nm 44 dB i = 5 nm 40 dB Therefore, it was found that the range of 20 nm ≦ i ≦ 90 nm is preferable.

As shown in FIG. 1 (c), when the high melting point component 3b is connected in the film surface direction and is deposited as a porous substance, if the "maximum pore size p" of the deposit is different, the number of rewritable times is It changed as follows.

[0258] From this result, it was found that the range of p ″ ≦ 80 nm is preferable.

When the "maximum wall thickness w" of the porous high melting point component 3b is different, the C / N of the reproduced signal after rewriting 10 ⁵ times under severe conditions with the laser light power being 15% higher than the optimum value is obtained. , Changed as follows: This change in C / N is
This is mainly due to the change in C level.

C / N w = 5 nm 50 dB w = 15 nm 49 dB w = 20 nm 46 dB w = 35 nm 40 dB of the reproduced signal after rewriting 10 ⁵ times From this result, it was found that the range of w ≦ 20 nm is preferable.

(Relationship with melting point of high melting point component) When the melting point (mp) of the high melting point component 3b deposited in the recording film 3 is different, the number of rewritable times changes as follows. It could be guessed by simulation.

[0262] From these results, it was found that the melting point of the high melting point component 3b is preferably in the range of 780 ° C or higher, and more preferably in the range of 930 ° C or higher.

If the difference between the melting point of the residual component (phase change component 3a) after the high melting point component 3b is deposited and the melting point of the high melting point component 3b is different, the number of rewritable times may change as follows. It could be estimated by computer simulation.

Number of rewritable times m. p. Difference = 0 ° C 7 × 10 ⁴ times m. p. Difference = 150 ° C. 1.5 × 10 ⁵ times m.p. p. Difference = 300 ° C. 2 × 10 ⁵ times From these results, it was found that the difference in melting point is preferably in the range of 150 ° C. or higher, more preferably in the range of 300 ° C. or higher.

(Relationship between High Melting Point Component and Difference in Crystallization Temperature of Phase Change) The temperature was raised at a constant rate of 10 ° C./min, and the temperature at which heat of crystallization started was measured. From the result, when the difference s between the crystallization temperatures of the high-melting point component 3b and the low-melting point component 3a that causes a phase change was obtained, the rewritable number changed as follows due to the temperature difference s.

[0266] From this result, it was found that the difference in melting point is preferably in the range of 10 ° C or higher, more preferably in the range of 30 ° C or higher.

(Relationship with high melting point component deposited during film formation) When the information recording thin film of this example was manufactured, the high melting point component Cr ₄ Te ₅ was deposited in the initial step. ,
When the average film thickness c ′ of the high melting point component Cr ₄ Te ₅ is changed as follows, reproduction after rewriting 10 ⁵ times under severe conditions where the number of rewritable times and the power of laser light is 15% higher than the optimum value The C / N of the signal changed as follows. This change in C / N is mainly due to the change in C level.

Number of rewritable times c ′ = 0 nm 5 × 10 ⁴ times c ′ = 1 nm 1 × 10 ⁵ times c ′ = 5 nm 2 × 10 ⁵ times 10 ⁵ times C / N of reproduced signal after rewriting c ′ = 1 nm 47 dB c ′ = 5 nm 47 dB c ′ = 10 nm 46 dB c ′ = 20 nm 40 dB From these results, it was found that the range of 1 nm ≦ c ′ ≦ 10 nm is preferable.

(Others) In this embodiment, the protective layer 2 and the intermediate layer 4 are made of ZnS-SiO _2, but
Instead of the ZnS-SiO _2, Si-N-based material, SiO
-N-based _{material, SiO 2, SiO, TiO 2} , Al 2 O 3, Y
₂ O ₃ , CeO, La ₂ O ₃ , In ₂ O ₃ , GeO, Ge
O ₂ , PbO, SnO, SnO ₂ , Bi ₂ O ₃ , TeO ₂ ,
Oxides such as WO ₂ , WO ₃ , Sc ₂ O ₃ , and ZrO ₂ , Ta
_{N, AlN, Si 3 N 4} , Al-Si-N material (e.g., AlSiN ₂₎ nitride such _{as, ZnS, Sb 2 S 3,} Cd
S, In ₂ S ₃ , Ga ₂ S ₃ , GeS, SnS ₂ , PbS,
Sulfides such as Bi ₂ S ₃ , SnSe ₂ , Sb ₂ Se ₃ , Cd
Se, ZnSe, In ₂ Se ₃ , Ga ₂ Se ₃ , GeSe,
GeSe ₂ , SnSe, PbSe, Bi ₂ Se ₃ and other selenides, CeF ₃ , MgF ₂ , CaF ₂ and other fluorides,
Alternatively, Si, Ge, TiB ₂ , B ₄ C, B, C, or a material having a composition close to that of the above materials may be used. Further, it may be a layer of these mixed materials or a multilayer of these.

When the intermediate layer 4 was omitted, the recording sensitivity was reduced by about 30% and the remaining loss was increased by about 5 dB. The number of rewrites also decreased.

When the refractive index of the intermediate layer 4 is in the range of 1.7 or more and 2.3 or less, the film thickness is in the range of 3 nm or more and 100 nm or less, and in the range of 180 nm or more and 400 nm or less, respectively, 50 dB or more. C / N was obtained.

Al-Ti used for the reflective layer 5 in this example.
Instead of Au, Ag, Cu, Al, Ni, Fe, C
A single element of o, Cr, Ti, Pd, Pt, W, Ta, Mo, or Sb, an alloy containing these as the main components, or a layer formed of an alloy of these elements may be used. Multiple layers may be used, or a composite layer of these and another substance such as an oxide may be used.

In this example, the polycarbonate substrate 1 having a surface on which irregularities such as tracking guides are directly formed
However, instead of this, polyolefin, epoxy, acrylic resin, chemically strengthened glass having an ultraviolet curable resin layer formed on its surface, or the like may be used.

A simple laminated structure in which a part of the intermediate layer 4, the reflection layer 5 and the protective layer 2 is omitted, for example, substrate 1 / protective layer 2 / recording film 3, substrate 1 / recording film 3 / intermediate layer 4, substrate 1 / Even with the configuration of the recording film 3 / reflection layer 5, etc.,
Even if the rewriting was performed many times, the noise increase was small and good results were obtained.

As described above, the information recording thin film of this embodiment has good recording / reproducing / erasing characteristics,
It is possible to rewrite many times, which is one digit or more, conventionally. There is also an advantage that the power of laser light used for recording / erasing may be low.

[Example 2] Sb-Te-Ge of Example 1
Sb—Te—In—Cr-based Cr ₁₂ I corresponding to the case where all Ge is replaced by In in the —Cr-based recording film 5.
n ₃₅ Sb ₁₂ Te ₄₀ , that is, (Cr ₄ Te ₅ ) ₂ (In ₃ S
An information recording thin film was manufactured in the same manner as in Example 1 except that the recording film 5 was formed of bTe ₂ ) ₇ . The initial crystallization of the thin film and the subsequent information recording / reproducing method were the same as in Example 1.

(Relationship with composition of elements other than Cr) With the Cr content kept constant, In ₆₅ Te of a triangular phase diagram (not shown)
_{When the} other composition was changed on the straight line connecting ₂₅ Cr ₁₀ and Sb 3 ₀ Te ₆₀ Cr ₁₀ , the crystallization temperature of the unrecorded part when the temperature was raised at a constant rate and the crystallization temperature at 80 ° C and relative humidity of 95% 100
The change in bit error rate when left for 0 hour is as follows.

Crystallization temperature Sb ₃₀ Te ₆₀ Cr ₁₀ 120 ° C Sb ₂₂ Te ₅₁ In ₁₇ Cr ₁₀ 140 ° C Sb ₁₈ Te ₄₇ In ₂₅ Cr ₁₀ 150 ° C Sb ₁₀ Te ₃₅ In ₄₅ Cr ₁₀ 170 ° C Sb ₇ Te ₃₃ In ₅₀ Cr ₁₀ 180 ° C Sb ₂ Te ₈ In ₆₀ Cr ₁₀ 220 ° C Change in bit error rate Sb ₂₂ Te ₅₁ In ₁₇ Cr ₁₀ 2 times Sb ₁₈ Te ₄₇ In ₂₅ Cr ₁₀ 2 times Sb ₁₀ Te ₃₅ In ₄₅ Cr ₁₀ 2 times Sb ₇ Te ₃₃ In ₅₀ Cr ₁₀ 2.5 times Sb ₂ Te ₈ In ₆₀ Cr ₁₀ 4 times As a result, a sufficiently high crystallization temperature can be obtained even if the composition other than Cr changes. It can be seen that the change in the bit error rate is not so large even after a large number of rewritings of 10 ⁵ times.

When the composition was changed on a straight line connecting Sb ₆₅ Te ₂₅ Cr ₁₀ and In ₄₇ Te ₄₃ Cr ₁₀ of the same triangular phase diagram with the Cr content kept constant, the crystallization temperature when the temperature was raised at a constant rate Then, the change in the bit error rate when left for 1000 hours at 80 ° C. and 95% relative humidity was as follows.

Crystallization temperature Sb ₂ Te ₄₂ In ₄₆ Cr ₁₀ 210 ° C Sb ₄ Te ₄₂ In ₄₄ Cr ₁₀ 200 ° C Sb ₈ Te ₄₁ In ₄₁ Cr ₁₀ 190 ° C Sb ₁₅ Te ₃₉ In ₃₆ Cr ₁₀ 180 ° C Sb ₃₀ Te ₃₄ In ₂₆ Cr ₁₀ 150 ° C Sb ₃₈ Te ₃₂ In ₂₀ Cr ₁₀ 130 ° C Sb ₄₁ Te ₃₂ In ₁₇ Cr ₁₀ 110 ° C Bit Error Rate Change Sb ₂ Te ₄₂ In ₄₆ Cr ₁₀ 5 times Sb ₄ Te ₄₂ In ₄₄ Cr ₁₀ 3 times Sb ₈ Te ₄₁ In ₄₁ Cr ₁₀ 2 times Sb ₁₅ Te ₃₉ In ₃₆ Cr ₁₀ 1.5 times Sb ₃₀ Te ₃₄ In ₂₆ Cr ₁₀ 1.5 times Sb ₃₈ Te ₃₂ In ₂₀ Cr ₁₀ 1 times Sb ₄₁ Te ₃₂ In ₁₇ Cr ₁₀ 1 times As a result, even if the composition other than Cr is changed, a sufficiently high crystallization temperature can be obtained, and the bit error rate can be improved even after rewriting as many as 10 ⁵ times. of Of it it can be seen that not too large.

The ratio of the In content p and the Sb content x (p
/ X), the change in bit error rate when left at 80 ° C. and 95% relative humidity for 1000 hours was as follows.

Change in bit error rate (p / x) = 0.5 3.0 times (p / x) = 1.0 2.0 times (p / x) = 2.0 2.0 times (p /X)=3.0 2.0 times (p / x) = 4.0 3.0 times From this result, the ratio (p / x) of the In content p and the Sb content x is 1. It can be seen that the change in bit error rate is small in the range of 0 ≦ (p / x) ≦ 3.0.

A material in which Cr is replaced by Cu, that is, In--
In the Sb-Te-Cu system, similar results were obtained also when the ratio (p / x) of the In content p and the Sb content x was changed.

(Another Example of Phase Change Component) A part of In ₃ SbTe ₂ which is a phase change component is replaced with Ge ₂ Sb ₂ Te ₅ and GeSb ₄ T.
e ₇ , GeSb ₂ Te ₄ , In ₃₅ Sb ₃₂ Te ₃₃ , In ₃₁ S
Even if it is replaced with at least one of b ₂₆ Te ₄₃ ,
Even if part of n is replaced with Ge, similar characteristics can be obtained.

(Another Example of High Melting Point Component) A part of Cr ₄ Te ₅ , which is a high melting point component, is replaced with LaTe ₃ , LaTe ₂ , La ₂ T.
e ₃ , La ₃ Te ₄ , LaTe, La ₂ Te ₅ , LaSb,
La ₄ Te ₇ , La ₃ Te, La ₂ Sb, La ₃ Sb ₂ , La
_{Sb 2, La 3 Ge, La} 5 Ge 3, La 4 Ge 3, La 5 G
e ₄ , LaGe, La ₃ Ge ₅ , Ag ₂ Te, Cr ₅ Te ₈ ,
Cr ₂ Te ₃ , CrSb, Cr ₃ Ge, Cr ₅ Ge ₃ , Cr
₁₁ Ge ₈ , CrGe, Cr ₁₁ Ge ₁₉ , PtTe ₂ , Pt ₄
Te ₅ , Pt ₅ Te ₄ , Pt ₄ Sb, Pt ₃ Sb ₂ , PtS
b, Pt ₃ Ge, Pt ₂ Ge, Pt ₃ Ge ₂ , PtGe, P
t ₂ Ge ₃ , PtGe ₃ , NiTe, NiTe _0.85 , Ni
Sb, Ni ₃ Ge, Ni ₅ Ge ₂ , Ni ₅ Ge ₃ , NiG
e, CoTe ₂ , CoSb ₂ , CoSb ₃ , Co ₅ Ge ₂ ,
Co ₅ Ge ₃ , CoGe, Co ₅ Ge ₇ , CoGe ₂ , Si ₂
Te ₃ , SiSb, SiGe, CeTe, Ce ₃ Te ₄ ,
Ce ₂ Te ₃ , Ce ₄ Te ₇ , CeTe ₂ , CeTe ₃ , Ce
₂ Sb, Ce ₅ Sb ₃ , Ce ₄ Sb ₅ , CeSb, CeS
b ₂ , Ce ₃ Ge, Ce ₅ Ge ₃ , Ce ₄ Ge ₃ , Ce ₅ G
e ₄ , CeGe, Ce ₃ Ge ₅ , Ce ₅ Si ₃ , Ce ₃ S
i ₂ , Ce ₅ Si ₄ , CeSi, Ce ₃ Si ₅ , CeSi ₂ ,
Cr ₃ Si, Cr ₅ Si ₃ , CrSi, CrSi ₃ , CrS
i ₂ , Co ₃ Si, CoSi, CoSi ₂ , NiSi ₂ , N
iSi, Ni ₃ Si ₂ , Ni ₂ Si, Ni ₅ Si ₂ , Ni ₃ S
i, Pt ₅ Si ₂ , Pt ₂ Si, PtSi, LaSi ₂ , A
g ₃ In, Ag ₂ In, Bi ₂ Ce, BiCe, Bi ₃ Ce
₄ , Bi ₃ Ce ₅ , BiCe ₂ , Cd ₁₁ Ce, Cd ₆ Ce,
Cd ₅₈ Ce ₁₃ , Cd ₃ Ce, Cd ₂ Ce, CdCe, Ce
₃ In, Ce ₂ In, Ce _{1 + x} In, Ce ₃ In ₅ , CeI
n ₂ , CeIn ₃ , Ce ₂ Pb, CePb, CePb ₃ , C
_{e 3 Sn, Ce 5 Sn 3} , Ce 5 Sn 4, Ce 11 Sn 10, C
_{e 3 Sn 5, Ce 3 Sn} 7, Ce 2 Sn 5, CeSn 3, Ce
_{Zn, CeZn 2, CeZn 3,} Ce 3 Zn 11, Ce 13 Z
_{n 58, CeZn 5, Ce 3} Zn 22, Ce 2 Zn 17, CeZ
n ₁₁ , Cd ₂₁ Co ₅ , CoGa, CoGa ₃ , CoSn,
Cr ₃ Ga, CrGa, Cr ₅ Ga ₆ , CrGa ₄ , Cu ₉
Ga ₄ , Cu ₃ Sn, Cu ₃ Zn, Bi ₂ La, BiLa,
Bi ₃ La ₄ , Bi ₃ La ₅ , BiLa ₂ , Cd ₁₁ La, C
d ₁₇ La ₂ , Cd ₉ La ₂ , Cd ₂ La, CdLa, Ga ₆
La, Ga ₂ La, GaLa, Ga ₃ La ₅ , GaLa ₃ ,
In ₃ La, In ₂ La, In ₅ La ₃ , In _x La, In
La, InLa ₂ , InLa ₃ , La ₅ Pb ₃ , La ₄ P
b ₃ , La ₁₁ Pb ₁₀ , La ₃ Pb ₄ , La ₅ Pb ₄ , LaP
b ₂ , LaPb ₃ , LaZn, LaZn ₂ , LaZn ₄ , L
_{aZn 5, La 3 Zn 22,} La 2 Zn 17, LaZn 11, L
aZn ₁₃ , NiBi, Ga ₃ Ni ₂ , GaNi, Ga ₂ N
i ₃ , Ga ₃ Ni ₅ , GaNi ₃ , Ni ₃ Sn, Ni ₃ S
n ₂ , Ni ₃ Sn ₄ , NiZn, Ni ₅ Zn ₂₁ , PtBi,
PtBi ₂ , PtBi ₃ , PtCd ₂ , Pt ₂ Cd ₉ , Ga ₇
Pt ₃ , Ga ₂ Pt, Ga ₃ Pt ₂ , GaPt, Ga ₃ P
t ₅ , GaPt ₂ , GaPt ₃ , In ₇ Pt ₃ , In ₂ Pt,
In ₃ Pt ₂ , InPt, In ₅ Pt ₆ , In ₂ Pt ₃ , In
Pt ₂ , InPt ₃ , Pt ₃ Pb, PtPb, Pt ₂ P
b ₃ , Pt ₃ Sn, PtSn, Pt ₂ Sn ₃ , PtSn ₂ ,
PtSn ₄ , Pt ₃ Zn, PtZn ₂ , AlS, Al
₂ S ₃ , BaS, BaC ₂ , CdS, Co ₄ S ₃ , Co
₉ S ₈ , CoS, CoO, Co ₂ O ₄ , Co ₂ O ₃ , Cr
₂ O ₃ , Cr ₃ O ₄ , CrO, CrS, CrN, Cr ₂ N,
Cr ₂₃ C ₆₃ , Cr ₇ C ₃ , Cr ₃ C ₂ , Cu ₂ S, Cu
₉ S ₅ , CuO, Cu ₂ O, In ₄ S ₅ , In ₃ S ₄ , La ₂ S
₃ , La ₂ O ₃ , Mo ₂ C, MoC, Mn ₂₃ C ₆ , Mn ₄ C,
Mn ₇ C ₃ , NiO, SiS ₂ , SiO ₂ , Si ₃ N ₄ , Cu
₂ Te, CuTe, Cu ₃ Sb, Mn ₂ Sb, MnTe, M
nTe ₂ , Mn ₅ Ge ₃ , Mn _3.25 Ge, Mn ₅ Ge ₂ , M
n ₃ Ge ₂ , Ge ₃ W, Te ₂ W, AlSb, Al ₂ Te ₃ ,
Fe ₂ Ge, FeGe ₂ , FeSb ₂ , Mo ₃ Sb ₇ , Mo ₃
Te ₄ , MoTe ₂ , PbTe, GePd ₂ , Ge ₂ Pd ₅ ,
Ge ₉ Pd ₂₅ , GePd ₅ , Pd ₃ Sb, Pd ₅ Sb ₃ , Pd
Sb, SnTe, Ti ₅ Ge ₃ , Ge ₃₁ V ₁₇ , Ge
₈ V ₁₁ , Ge ₃ V ₅ , GeV ₃ , V ₅ Te ₄ , V ₃ Te ₄ , Zn
Te, Ag ₂ Se, Cu ₂ Se, Al ₂ Se ₃ , InAs,
CoSe, Mn ₃ In, Ni ₃ In, NiIn, Ni ₂ I
a high melting point compound such as n ₃ , Ni ₃ In ₇ , PbSe, or a high melting point oxide of the constituent elements of the above high melting point component;
Similar results can be obtained by substituting at least one of the compounds having a composition close to that or a mixed composition thereof or a compound of three or more elements close to the mixed composition.

Of these, LaSb, La ₂ Te ₃ ,
La ₃ Te ₄ , CrSb, CoSb, Cr ₃ Te ₄ , Cr ₂
Te ₃ , Cr ₃ Te ₄ , CoTe, Co ₃ Te ₄ , Cu ₂ T
e, CuTe, Cu ₃ Sb, MnTe, MnTe ₂ , Mn
_At least one of ₂ Sb and Cr ₄ Te ₅ is particularly preferable. This is because the recording / erasing characteristics are stabilized by a small number of initial crystallizations.

Also in this embodiment, the high melting point component 3b to be precipitated may be a compound, a simple element or an alloy.

(Amount of Inclusion of High Melting Point Component) As in Example 1, oxides, sulfides, etc. contained in the precipitate of high melting point component,
The content of nitrides and carbides is preferably less than 40 atomic% of the high melting point component, and particularly preferably less than 10 atomic%. If the content of these components is large, there is a problem that the difference in complex refractive index from the phase change component cannot be reduced, or oxygen or the like diffuses into the phase change component to deteriorate recording / reproducing characteristics.

Items not mentioned here are the same as in the first embodiment.

[Example 3] Sb-Te-Ge of Example 1
In the --Cr-based recording film 5, B or X in the general formula is used.
Sb ₁₆ Te ₃₉ Ge ₁₅ Co ₂₂ Si ₈ containing Co and Si instead of Cr as the element represented by, that is, (Co ₃ S
Aside from forming a recording film 5 by _{i) 27 (Ge 2 Sb 2} Te 5) 28 , the same procedure as in Example 1, it was manufactured information recording thin film. The initial crystallization of the thin film and the subsequent information recording / reproducing method were the same as in Example 1.

In this example, the high melting point component was Co ₃ S.
i, the phase change component is Ge ₂ Sb ₂ Te ₅ .

The ratio a of Sb to Te to Ge, x, y, and p was kept at x: y: p = 2: 5: 2, and the Co ₃ Si content a (corresponding to a in Example 1) was adjusted. When changed, the number of rewritable times and the C of the reproduced signal after rewriting 10 ⁵ times under severe conditions in which the power of the laser beam is 15% higher than the optimum value
The change in / N was the same as in Example 1.

(Another Example of Phase Change Component) A part or all of Ge ₂ Sb ₂ Te ₅ , which is a phase change component, is replaced with GeSb ₄ Te ₇ ,
GeSb ₂ Te ₄ , In ₃ SbTe ₂ , In ₃₅ Sb ₃₂ T
Even if it is replaced with at least one of e ₃₃ and In ₃₁ Sb ₂₆ Te ₄₃ , or if part or all of Ge is replaced with In, similar characteristics can be obtained.

(Other Examples of High Melting Point Component) Part or all of Co ₃ Si which is a high melting point component is Ce ₅ Si ₃ or Ce ₃ S.
i ₂ , Ce ₅ Si ₄ , CeSi, Ce ₃ Si ₅ , CeSi ₂ ,
Cr ₅ Si ₃ , CrSi, CrSi ₃ , CrSi ₂ , Cr ₃
Si, CoSi, CoSi ₂ , NiSi ₂ , NiSi, N
i ₃ Si ₂ , Ni ₂ Si, Ni ₅ Si ₂ , Ni ₃ Si, Pt ₅
Si ₂ , Pt ₂ Si, PtSi, LaSi ₂ , Bi ₂ Ce,
BiCe, Bi ₃ Ce ₄ , Bi ₃ Ce ₅ , BiCe ₂ , Cd
₁₁ Ce, Cd ₆ Ce, Cd ₅₈ Ce ₁₃ , Cd ₃ Ce, Cd ₂
Ce, CdCe, Ce ₂ Pb, CePb, CePb ₃ , C
_{e 3 Sn, Ce 5 Sn 3} , Ce 5 Sn 4, Ce 11 Sn 10, C
_{e 3 Sn 5, Ce 3 Sn} 7, Ce 2 Sn 5, CeSn 3, Ce
_{Zn, CeZn 2, CeZn 3,} Ce 3 Zn 11, Ce 13 Z
_{n 58, CeZn 5, Ce 3} Zn 22, Ce 2 Zn 17, CeZ
n ₁₁ , Cd ₂₁ Co ₅ , CoGa, CoGa ₃ , CoSn,
Cr ₃ Ga, CrGa, Cr ₅ Ga ₆ , CrGa ₄ , Cu ₉
Ga ₄ , Cu ₃ Sn, Cu ₃ Zn, Bi ₂ La, BiLa,
Bi ₃ La ₄ , Bi ₃ La ₅ , BiLa ₂ , Cd ₁₁ La, C
d ₁₇ La ₂ , Cd ₉ La ₂ , Cd ₂ La, CdLa, Ga ₆
La, Ga ₂ La, GaLa, Ga ₃ La ₅ , GaLa ₃ ,
La ₅ Pb ₃ , La ₄ Pb ₃ , La ₁₁ Pb ₁₀ , La ₃ Pb ₄ ,
_{La 5 Pb 4, LaPb 2,} LaPb 3, LaZn, LaZ
_{n 2, LaZn 4, LaZn 5} , La 3 Zn 22, La 2 Zn
₁₇ , LaZn ₁₁ , LaZn ₁₃ , NiBi, Ga ₃ Ni ₂ ,
GaNi, Ga ₂ Ni ₃ , Ga ₃ Ni ₅ , GaNi ₃ , Ni ₃
Sn, Ni ₃ Sn ₂ , Ni ₃ Sn ₄ , NiZn, Ni ₅ Zn
₂₁ , PtBi, PtBi ₂ , PtBi ₃ , PtCd ₂ , P
t ₂ Cd ₉ , Ga ₇ Pt ₃ , Ga ₂ Pt, Ga ₃ Pt ₂ , Ga
Pt, Ga ₃ Pt ₅ , GaPt ₂ , GaPt ₃ , Pt ₃ P
b, PtPb, Pt ₂ Pb ₃ , Pt ₃ Sn, PtSn, P
t ₂ Sn ₃ , PtSn ₂ , PtSn ₄ , Pt ₃ Zn, PtZ
Substituted with at least one of a high melting point compound containing two or more elements represented by B such as n ₂ or a compound having a composition close to that, a mixed composition thereof, or a ternary or more compound close to the mixed composition. Produces similar results.

Items not mentioned here are the same as in the first embodiment.

[Embodiment 4] (Structure / Manufacturing Method) FIG. 3 shows a sectional structure of a disk-shaped information recording medium using the information recording thin film of the first embodiment of the present invention. This medium was manufactured as follows.

First, a polycarbonate substrate 1 having a diameter of 13 cm and a thickness of 1.2 mm and having a tracking groove having a U-shaped cross section on its surface was formed. Next, the substrate 1 was placed in a magnetron sputtering apparatus in order to sequentially form a thin film on the substrate 1. This apparatus has a plurality of targets and is capable of sequentially forming laminated films.
Moreover, the uniformity and reproducibility of the formed film thickness are excellent.

First, (ZnS) 80%. (SiO ₂ ) 2 was formed on the substrate 1 by using a magnetron sputtering device.
The protective layer 2 made of 0%, that is, a (Zn ₄₀ S ₄₀ Si ₇ O ₁₃ ) film was formed to have a film thickness of about 130 nm. Then, a Cr ₄ Te ₅ film (not shown) which is a high melting point component is formed in an island shape on the protective layer 2 to an average film thickness of 3 nm, and then Cr ₉ Ge ₇ Sb ₂₇ Te ₅₇ , that is, ((GeSb ₄
A recording film 3 having a composition of Te ₇ ) ₈ (Cr ₄ Te ₅ ) ₂ ) was formed to a film thickness of about 22 nm. At this time, a rotating simultaneous sputtering method using a Cr ₄ Te ₅ target and a GeSb ₄ Te ₇ target was used.

The Cr ₄ Te ₅ film does not necessarily have to be formed. However, in that case, the flow of the recording film is somewhat likely to occur. When the Cr ₄ Te ₅ film is not formed, the high melting point component precipitated in the recording film 3 is only the high melting point component generated during the initialization described later.

Next, on the recording film 3, (ZnS) ₈₀ (Si
After forming the intermediate layer 4 of O ₂ ) ₂₀ film to a film thickness of about 40 nm, Al _{97 is} formed on the intermediate layer 4 in the same sputtering apparatus.
The reflection layer 5 made of a Ti ₃ film was formed to a film thickness of 200 nm. Thus, the first disc member was obtained.

On the other hand, a second disk member having the same structure as the first disk member was obtained by the completely same method. The second disc member has a diameter of 13 cm and a thickness of 1.2.
The film thickness is about 130 nm, which is sequentially stacked on the substrate 1'of mm.
Of the (ZnS) ₈₀ (SiO ₂ ) ₂₀ film,
Cr ₄ Te ₅ film (not shown) with an average film thickness of 3 nm, film thickness of about 2
2 nm of Cr ₉ Ge ₇ Sb ₂₇ Te ₅₇ , that is ((GeS
b ₄ Te ₇ ) ₈ (Cr ₄ Te ₅ ) ₂ ) recording film 3 ′, film thickness about 4
It is provided with an intermediate layer 4 ′ made of a 0 nm (ZnS) ₈₀ (SiO ₂ ) ₂₀ film and a reflective layer 5 ′ made of a 200 nm thick Al ₉₇ Ti ₃ film.

Thereafter, the reflective layers 5 and 5'of the first and second disk members were bonded together via the adhesive layer 6 to obtain the disk-shaped information recording medium shown in FIG.

In this medium, if the entire surfaces of the reflective layers 5 and 5'are adhered, the number of rewritable times can be increased as compared with the case where the entire surfaces are not adhered, and the recording areas of the reflective layers 5 and 5'can be handled. The recording sensitivity was slightly higher when the adhesive was not applied to the areas to be treated than when the adhesive was applied to the areas as well.

(Initialization) The recording films 3, 3'of the medium manufactured as described above were initialized as follows. Since the same applies to the recording film 3 ', only the recording film 3 will be described below.

The medium is rotated at 1800 rpm, the laser light power of the semiconductor laser (wavelength 830 nm) is maintained at a level (about 1 mW) at which recording is not performed, and the laser light has a numerical aperture (NA) of 0. The light was condensed by the lens 55 and was irradiated onto the recording film 3 through the substrate 1. The reflected light from the recording film 3 is detected, and tracking is performed so that the center of the laser light spot is always aligned with the center of the tracking groove of the substrate 1 or between the grooves and the center of the groove. The recording head was driven while performing automatic focusing so that the focal point comes into focus.

First, for initialization, the same recording track of the recording film 5 was irradiated with continuous (DC) laser light having a power of 15 mW 200 times. The irradiation time (light spot passage time) at each time is about 0.1 μsec.

Then, a continuous laser beam having a power of 7 mW is supplied for 5 times.
Irradiated twice. Irradiation time of each time (light spot passage time)
Is about 0.1 μsec. The laser light power at this time may be in the range of 5 to 9 mW.

Of the two types of laser light irradiation, the irradiation with the lower power (7 mW) may be omitted, but the irradiation has better erasing characteristics.

In this way, by irradiating laser beams having different powers, initialization can be sufficiently performed.

Irradiation of these laser beams is performed by a semiconductor laser
If an array is used, or a light beam from a gas laser is divided into a plurality of beams, or the spot shape of the light beam from a high-power gas laser or a semiconductor laser is made into an ellipse elongated in the radial direction of the medium. , And more preferably. This makes it possible to complete the initial crystallization by rotating the medium a few times.

When a plurality of laser light spots are used, if the laser light spots are not arranged on the same recording track but the positions are gradually shifted in the radial direction of the medium, a wide range can be obtained by one irradiation. Can be initialized,
It has the effect of reducing the remaining loss.

Next, each time a continuous laser beam of 12 mW in a circular spot (high power light for initialization) is irradiated once (irradiation time: about 0.1 μsec), a pulsed laser beam of power 15 mW (for recording) is used. High power light) to irradiate the recording film 5
Was amorphized to form recording points. Then, it was examined how many times it was necessary to irradiate the recording point with 7 mW of continuous laser light (low power light for erasing) to crystallize.

In the disk of this example, the number of times of continuous laser light irradiation of 12 mW up to 100 times was reduced as the number of times of irradiation increased, and the number of times of continuous laser light irradiation of 7 mW required for crystallization decreased. That is, it was found that crystallization was more likely to occur as the number of irradiations increased. This is because irradiation with a continuous laser beam of 12 mW causes a large number of fine crystals of Cr ₄ Te ₅ which is a high melting point component to precipitate in the recording film 5, and the composition of the rest (phase change part) can be crystallized at high speed. GeSb
It is presumed that the composition was close to that of ₄ Te ₇ .

On the other hand, assuming a signal of the mark edge recording system, it corresponds to the repetition of the recording mark of 2T and the space of 8T while randomly shifting the signal writing start position on the recording track within the range of 16T (1T is 45 ns). In the case of recording a signal in which the signal A to be recorded and the signal B corresponding to the repetition of the recording mark of 8T and the space of 2T are alternately recorded, the mark forming frequency changes abruptly at the switching portion of the signal A and the signal B. Therefore, when the recording film flows, the flowing recording film material is stopped and deposited, or the recording film material flows out without inflowing from the rear and the film thickness becomes thin. Distortion occurs. When the element in the recording film segregates, the element also accumulates or becomes insufficient. When the flow or segregation occurs to some extent, the reverse flow or segregation easily occurs due to the film thickness or the concentration gradient, and the brake is applied. Therefore, by repeatedly irradiating a high power (15 mW) continuous light slightly wider than the recording area before using the disc, the above-mentioned change in the recording area can be prevented to some extent. Therefore, the required number of times of repeated irradiation of the continuous light was determined by using the magnitude of the waveform distortion due to the above-mentioned rewriting of the signal a number of times for each disk as an index. As described above, the larger the required number of times of irradiation for sufficiently increasing the crystallization rate and the necessary number of times of irradiation for reducing the waveform distortion is the required number of times for initialization of the disk.
In the disk of this example, the number of times required for the crystallization rate to be sufficiently high was larger, and 100 times was the necessary number of times of initialization irradiation.

The melting point of Cr ₄ Te ₅ is 1252 ° C., and the melting point of GeSb ₄ Te ₇ is 605 ° C.

(Relationship with Ge content a 1: GeSb ₄
(Near Te ₇ ) When the composition is changed on a straight line that keeps the Cr content connecting Ge ₆₅ Te ₂₅ Cr ₁₀ and Sb ₃₀ Te ₆₀ Cr ₁₀ in the triangular phase diagram of FIG. The crystallization temperature of the recorded portion and the number of laser irradiations for initialization were measured. As a result, the following data were obtained.

Composition Crystallization temperature Laser irradiation frequency Sb ₃₀ Te ₆₀ Cr ₁₀ 120 ° C 200 times or less Ge ₂ Sb ₂₉ Te ₅₉ Cr ₁₀ 130 ° C 200 times or less Ge ₄ Sb ₂₈ Te ₅₈ Cr ₁₀ 150 ° C 200 times or less Ge ₁₀ Sb ₂₅ Te ₅₅ Cr ₁₀ 160 ° C 200 times or less Ge ₁₅ Sb ₂₃ Te ₅₂ Cr ₁₀ 170 ° C 500 times Ge ₁₇ Sb ₂₂ Te ₅₁ Cr ₁₀ 170 ° C 2000 times Ge ₂₅ Sb ₁₈ Te ₄₇ Cr ₁₀ 180 ° C 5000 times From this result, an appropriate crystallization temperature can be obtained within the range of 0.02 ≦ a ≦ 0.19, and the number of laser irradiation for initialization can be reduced.

(Relationship with Sb content b 1: -GeSb ₄
(Near Te ₇ ) Crystals when the composition is changed on a straight line connecting the Sb ₄₅ Te ₄₅ Cr ₁₀ and Ge ₁₈ Te ₇₂ Cr ₁₀ in the triangular phase diagram of FIG. The conversion temperature and the number of laser irradiations for initialization were measured.
As a result, the following data were obtained.

Composition Crystallization temperature Laser irradiation frequency Ge ₁₇ Sb ₂ Te ₇₁ Cr ₁₀ 210 ° C 5000 times Ge ₁₇ Sb ₄ Te ₆₉ Cr ₁₀ 200 ° C 1000 times Ge ₁₄ Sb ₁₀ Te ₆₆ Cr ₁₀ 180 ° C 500 times Ge ₁₀ Sb ₂₀ Te ₆₀ Cr ₁₀ 170 ° C 200 times or less Ge ₇ Sb ₂₆ Te ₅₇ Cr ₁₀ 160 ° C 200 times or less Ge ₅ Sb ₃₃ Te ₅₂ Cr ₁₀ 150 ° C 200 times or less Ge ₃ Sb ₃₆ Te ₅₁ Cr ₁₀ 140 ° C 200 times or less Ge ₂ Sb ₄₀ Te ₄₈ Cr ₁₀ 120 ° C 200 times or less From these results, in the range of 0.04 ≦ b ≦ 0.4
A suitable crystallization temperature can be obtained, and the number of laser irradiation shots for initialization can be reduced.

(Relationship with Te content c 1: -GeSb ₄
Neighboring Te ₇ ) Necessary for erasing recorded information by changing the composition on a straight line with a constant Cr content connecting Sb ₁₅ Te ₇₅ Cr ₁₀ and Ge ₃₀ Sb ₆₀ Cr ₁₀ in the triangular phase diagram of FIG. The change in carrier-to-noise ratio (C / N) of the reproduced signal after rewriting 10 ⁵ times under severe conditions in which the laser light irradiation time and the laser light power were made 15% higher than the optimum value was measured. As a result, the following data were obtained.

After rewriting 10 ⁵ times, C / N Ge ₁₄ Sb ₃₆ Te ₄₀ Cr ₁₀ 0.5 μsec ₄₄ dB Ge ₁₂ Sb ₃₃ Te ₄₅ Cr ₁₀ 0.2 μsec 48 dB Ge ₁₁ Sb ₃₁ Te of the composition laser light irradiation time _{48 Cr 10 0.1μsec 50dB Ge 8 Sb} 27 Te 55 Cr 10 0.1μsec 50dB Ge 5 Sb 22 Te 63 Cr 10 0.5μsec 50dB Ge 3 Sb 19. 5 Te 67. 5 Cr 10 1.0μsec 50dB Sb 15 Te ₇₅ Cr ₁₀ 3.0 μsec 50 dB From this result, in the range of 0.5 ≦ c ≦ 0.75,
The irradiation time of the laser beam required for erasing can be shortened, and the laser beam power is increased by 15% above the optimum value under severe conditions.
Carrier-to-noise ratio of ⁵ times the reproduction signal after rewriting (C /
N) can be improved.

(Relationship with Cr content d 1: -GeSb ₄
Near Te ₇ ) Cr ₄ Te ₅ which is the remainder of Ge vs Sb vs Te
When the content of Cr ₄ Te ₅ was changed while maintaining the ratio of the contents a, b, and c of a: b: c = 1: 4: 7, the laser light power was increased by 15% from the optimum value. 10 under severe conditions
^When the C / N of the reproduced signal after rewriting ⁵ times was measured, the following results were obtained regarding the Cr content d.

Reproduction signal after rewriting 10 ⁵ times C / N d = 0 42 dB d = 3 48 dB d = 10 50 dB d = 20 50 dB d = 34 48 dB When the Cr content d is changed, the power of the laser beam is optimized. The number of initializations is set to 20 under the strict condition of 15% higher than the value.
The "erase ratio" of the reproduced signal when the signal was recorded once, and overwritten once, was changed as follows.

Here, the "erase ratio" is the ratio of the signal before and after overwriting when another signal having a different frequency is overwritten on the already recorded signal in dB.

Erasure ratio of reproduced signal when signal is recorded once and overwritten once d = 10 28 dB d = 20 25 dB d = 30 25 dB d = 40 20 dB As a result, the Cr content d increases. It can be seen that the erasing ratio decreases as time goes by.

From this result, it is possible to reduce the irradiation time of the laser beam required for erasing within the range of 0.03 ≦ d ≦ 0.3, and to perform 10 ⁵ times under the severe condition that the laser beam power is 15% higher than the optimum value. The carrier-to-noise ratio (C / N) of the reproduced signal after rewriting can be improved.

The average composition of the recording thin film is expressed by the formula L _j H _k by the low melting point component L of the element simple substance or the compound composition and the high melting point component H of the element simple substance or the compound composition, and the content k is changed. In this case, the crystallization temperature and laser power should be increased by 15% under severe conditions.
The C / N of the reproduced signal after rewriting ^five times changed as follows.

C / N crystallization temperature (GeSb ₄ Te ₇ ) ₉₅ (Cr ₄ Te ₅ ) ₅ 45 dB 170 ° C. (GeSb ₄ Te ₇ ) ₉₀ (Cr ₄ Te ₅ ) of the composition reproduction signal after rewriting 10 ⁵ times ) ₁₀ 48 dB 170 ° C. (GeSb ₄ Te ₇ ) ₈₀ (Cr ₄ Te ₅ ) ₂₀ 50 dB 160 ° C. (GeSb ₄ Te ₇ ) ₆₅ (Cr ₄ Te ₅ ) ₃₅ 50 dB 150 ° C. (GeSb ₄ Te ₇ ) ₅₀ (Cr ₄ Te ₅ ) _{50 50} dB 130 ° C. (GeSb ₄ Te ₇ ) ₄₀ (Cr ₄ Te ₅ ) ₆₀ 49 dB 120 ° C. From these results, it was found that the range of 20 ≦ k / (j + k) ≦ 40 is preferable.

(Relationship with high melting point component deposited during film formation) When the information recording thin film of this example was manufactured, the high melting point component Cr ₄ Te ₅ was deposited in the initial step. ,
When the average film thickness z of the high melting point component Cr ₄ Te ₅ is changed as follows, the reproduction signal after rewriting 10 ⁵ times under severe conditions in which the number of rewritable times and the laser light power is 15% higher than the optimum value The C / N of was changed as follows. This C
The change in / N is mainly due to the change in C level.

Number of rewritable times z = 0 nm 5 × 10 ⁴ times z = 1 nm 1 × 10 ⁵ times z = 5 nm 2 × 10 ⁵ times 10 ⁵ times C / N of reproduced signal after rewriting z = 1 nm 47 dB z = 5 nm 47 dB z = 10 nm 46 dB z = 20 nm 40 dB From these results, it was found that the range of 1 nm ≦ z ≦ 10 nm is preferable.

(Other Materials for Protective Layer, Intermediate Layer, and Reflective Layer) In this example, the protective layer 2 and the intermediate layer 4 were made of Z.
It is formed of nS-SiO _2, but ZnS-SiO ₂
Instead of Si-N-based material, Si-O-N-based material, Si
O ₂ , SiO, TiO ₂ , Ta ₂ O ₅ , Al ₂ O ₃ , Y ₂ O ₃ ,
CeO, La ₂ O ₃ , In ₂ O ₃ , GeO, GeO ₂ , Pb
O, SnO, SnO ₂ , Bi ₂ O ₃ , TeO ₂ , WO ₂ , W
O _3, Sc ₂ O _3, oxides such as ZrO _2, TaN, Al
_{N, Si 3 N 4, AlSi} -N -based material (e.g., AlSi
N ₂₎ nitride such _{as, ZnS, Sb 2 S 3,} CdS, In 2
S ₃ , Ga ₂ S ₃ , GeS, SnS ₂ , PbS, Bi ₂ S ₃ ,
Sulfides such as SnSe ₂ , Sb ₂ Se ₃ , CdSe, Z
nSe, In ₂ Se ₃ , Ga ₂ Se ₃ , GeSe, GeSe
₂ , SeSe, PbSe, Bi ₂ Se ₃ and other selenides, CeF ₃ , MgF ₂ , CaF ₂ and other fluorides, Si, Ge, TiB ₂ , B ₄ C, B, C, or the above materials You may use the thing of a similar composition. Further, it may be a layer of these mixed materials or a multilayer of these.

In the case of multiple layers, a material containing 70 mol% or more of ZnS, such as (ZnS) ₈₀ (SiO ₂ ) ₂₀ and Si,
A material containing 70 atomic% or more of at least one of Ge, such as Si, or an oxide of Si, such as SiO.
2-layer film with ₂ being preferred. In this case, in order to prevent a decrease in recording sensitivity, the ZnS—SiO ₂ layer is provided on the recording film side and its thickness is set to 3 nm or more. Further, in order to exert the effect of suppressing the flow of the recording film due to the low thermal expansion coefficient of the layer such as SiO ₂ , the thickness is preferably 10 nm or less. This two-layer film is preferably provided instead of the protective layer 2, but may be provided instead of the intermediate layer 4. As a substitute for the protective layer 2, the thickness of a layer such as SiO ₂ is preferably 50 nm or more and 250 nm or less. When a two-layer film is provided instead of the intermediate layer, SiO ₂
The layer thickness is preferably 10 nm or more and 80 nm or less. Providing these two-layer films is preferable not only when using the recording film of the present invention, but also when using other phase change recording films.

Further, it is preferable to use a two-layer film in which ZnS-SiO ₂ and an Au layer are provided on the substrate side because the degree of freedom in determining the reflectance is increased. At this time, the thickness of the Au layer is preferably 30 nm or less. Instead of Au, for example, Au—Co, Au
-Cr, Au-Ti, Au-Ni, Au-Ag, etc. Au
You may use the mixed material which has as a main component.

When the intermediate layer 4 was omitted, the recording sensitivity was reduced by about 30% and the remaining loss was increased by about 5 dB. The number of rewrites also decreased.

When the refractive index of the intermediate layer 4 is in the range of 1.7 or more and 2.3 or less, the film thickness is in the range of 3 nm or more and 100 nm or less, and in the range of 180 nm or more and 400 nm or less, respectively, 50 dB or more. C / N was obtained.

Al-Ti used for the reflective layer 5 in this example.
Instead of, the Si-Ge mixed material as the material of the reflective layer can make the light absorptance of the recording mark portion smaller than the light absorptance of the portion other than the recording mark. Moreover, the number of rewritable times does not decrease. When the Ge content is 10 atomic% or more and 80 atomic% or less, the number of rewritable times does not easily decrease.

Next, similar results were obtained with Si--Sn or Si--In mixed materials, or mixed materials of two or more kinds of these mixed materials. When these reflective layer materials are used not only as the phase change film of the present invention but also as a reflective layer material when another phase change film is used, the number of rewritable times does not decrease as compared with conventional reflective layer materials.

Furthermore, Si, Ge, C, Au, Ag, C
u, Al, Ni, Fe, Co, Cr, Ti, Pd, P
A single element of t, W, Ta, Mo, Sb, an alloy containing them as a main component, or a layer made of an alloy of these elements may be used, or a multi-layer made of these layers may be used. Alternatively, a composite layer of these and another substance such as an oxide may be used.

In this embodiment, a polycarbonate substrate 1 having a surface provided with irregularities such as a tracking guide is directly formed.
However, instead of this, polyolefin, epoxy, acrylic resin, chemically strengthened glass having an ultraviolet curable resin layer formed on its surface, or the like may be used.

A simple laminated structure in which a part of the intermediate layer 4, the reflective layer 5 and the protective layer 2 is omitted, for example, substrate 1 / protective layer 2 / recording film 3, substrate 1 / recording film 3 / intermediate layer 4, substrate 1 / Even with the configuration of the recording film 3 / reflection layer 5, etc.,
Even if the rewriting was performed many times, the noise increase was small and good results were obtained.

As described above, the information recording thin film of this embodiment maintains good recording / reproducing / erasing characteristics,
It is possible to rewrite a number of times as compared with the conventional method. Also, record
There is also an advantage that the power of the laser light used for erasing may be low.

Items not mentioned here are the same as in the first embodiment.

Example 5 Ge-Sb-Te of Example 1
The recording film 5 was formed of a composition Ge ₄₀ Sb ₁₀ Te ₄₀ Cr ₁₀ near the Ge ₅₀ Te ₅₀ composition in the -Cr recording film 5. As the structure, a metal layer having a thickness of 15 nm, a protective layer having a thickness of 20 nm, a recording film having a thickness of 20 nm, an intermediate layer having a thickness of 40 nm, and a reflective layer having a thickness of 70 nm were formed under the protective layer. The material is Au for the metal layer and the reflective layer.
It was used. An information recording thin film was produced in the same manner as in Example 1 except for the above. Also, the initialization of the thin film and the subsequent information recording / reproducing method were the same as in the example.

(Relationship with Sb content b-2: near GeTe composition) Ge ₄₅ Te ₄₅ Cr ₁₀ and Sb in the triangular phase diagram of FIG.
_The composition was changed on a straight line with a constant Cr content connecting ₉₀ Cr _10, and the difference in reflectance between when amorphized and when crystallized was measured. As a result, the following data were obtained.

[0345] From this, in the vicinity of the GeTe composition, 0 ≦ b ≦ 0.
It was found that a high reflectance difference was obtained in the range of 2. Sb
Was added in the range of 0.01 ≦ b ≦ 0.2, it was possible to prevent cracking at 60 relative humidity of 80%. However, finer composition control is required as compared with the film without Sb added.

(Relationship with Ge and Te contents a and c-2:
(Around GeTe composition) Sb ₁₀ Te ₈₀ C in the triangular phase diagram of FIG.
The composition was changed on a straight line with a constant Cr content connecting r ₁₀ and Ge ₈₀ Sb ₁₀ Cr _10, and the reflectance difference between when amorphized and when crystallized was measured. As a result, the following data were obtained.

[0347] From this, 0.25 ≦ a near the GeTe composition
It was found that a high reflectance difference was obtained in the range of ≤0.65, 0.35 ≤c≤0.75.

(Relationship with Cr content d-2: GeTe composition vicinity) The ratio of the content a, b, c of Ge to Sb to Te, which is the balance of Cr ₄ Te ₅ , is a: b: c = 4. When the content of Cr ₄ Te ₅ was changed to 1: 4, the C / N of the reproduced signal after rewriting 10 ⁵ times under severe conditions in which the power of the laser beam was increased by 15% from the optimum value was measured. I did, C
The following results were obtained regarding the content d of r.

Reproduction signal after rewriting 10 ⁵ times C / N d = 0 42 dB d = 3 48 dB d = 10 50 dB d = 20 50 dB d = 34 48 dB When the Cr content d is changed, the power of the laser beam is optimized. The number of initializations is set to 20 under the strict condition of 15% higher than the value.
The "erase ratio" of the reproduced signal when the signal was recorded once, and overwritten once, was changed as follows.

Here, the "erase ratio" is the ratio of the signal before and after overwriting when another signal having a different frequency is overwritten on the already recorded signal in dB.

Erasure ratio of reproduced signal when the signal is recorded once and then overwritten once d = 10 28 dB d = 20 25 dB d = 30 25 dB d = 40 20 dB As a result, the Cr content d increases. It can be seen that the erasing ratio decreases as time goes by.

From this result, a sufficiently high erasing ratio was obtained in the range of 0.03 ≦ d ≦ 0.3, and reproduction after rewriting 10 ⁵ times under severe conditions with the laser light power being 15% higher than the optimum value. The carrier-to-noise ratio (C / N) of the signal can be improved.

Items not mentioned here are the same as in the first embodiment.

Example 6 An information recording thin film was prepared in the same manner as in Example 1 except that the recording film 5 of Example 1 was changed in the film thickness direction of the high melting point component. did. Further, other than that, the disk-shaped information recording medium used in Example 1 was manufactured in the same manner. The initialization and the subsequent recording / reproducing method were the same as in the first embodiment.

(Structure / Manufacturing Method) The formation of a recording film in which the content of the high melting point component was changed in the film thickness direction
Cr ₄ Te ₅ target and G by sputtering equipment
A rotating co-sputtering method with an eSb ₄ Te ₇ target was used. At this time, a Cr ₄ Te ₅ film was first formed to a thickness of 3 nm, and then the voltage applied to the GeSb ₄ Te ₇ target was made constant and the voltage applied to the Cr ₄ Te ₅ target was gradually decreased as shown below. It was.

Sputtering time Sputtering power (W) Content of Cr ₄ Te ₅ from light incident side (seconds) GeSb ₄ Te ₇ target Cr ₄ Te ₅ target Recording film thickness (nm) (atomic%) 0-9 49 150 0 to 6 50 10 to 20 49 100 6 to 12 40 21 to 33 49 65 13 to 18 30 34 to 47 49 40 19 to 24 20 48 to 63 49 20 24 to 30 10 In addition to this, Cr ₄ Te ₅ target Even if the voltage applied to the GeSb ₄ Te ₇ target is gradually increased while the voltage applied to the target is gradually increased, it is possible to form a recording film in which the content of the high melting point component changes in the film thickness direction. The recording characteristics were better when the applied voltage was gradually changed. Moreover, in the in-line sputtering apparatus, the area of the composition of Cr ₄ Te ₅ and GeSb ₄
The target having the Te ₇ composition area gradually changed can be specified and similarly manufactured. A disc having this recording film was produced.

This disk is more complicated to manufacture than a recording film in which the content of the high melting point component is constant in the film thickness direction as in Example 1, but the number of laser irradiation for initialization can be reduced. .

Items not mentioned here are the same as in the first embodiment.

[Embodiment 7] FIG. 12 shows an example of a structural sectional view of a disk using a super-resolution readout film according to the present invention.

In the manufacture of the disk of FIG. 12, first, a polycarbonate substrate 11 having a diameter of 13 cm and a thickness of 1.2 mm, on which information was recorded by unevenness, was formed. next,
This substrate is provided with a plurality of targets so that a laminated film can be sequentially formed, and the substrate is mounted in a magnetron sputtering apparatus with good film thickness uniformity and reproducibility, and a thickness of 12 is formed on the substrate.
A 5 nm (ZnS) ₈₀ (SiO ₂ ) ₂₀ layer 12 was formed. Then, the Cr ₄ Te ₅ target was set to G
The eSb ₂ Te ₄ target was co-sputtered with a DC power source to form a super-resolution readout film (Cr ₄ Te ₅ ) ₂₀ (Ge
The Sb ₂ Te ₄ ) ₈₀ film 13 was formed to a thickness of 30 nm. Then (Z
nS) ₈₀ (SiO ₂ ) ₂₀ layer 14 of 20 nm, Al ₉₇ Ti
_{The three} layers 15 were sequentially laminated to have a film thickness of 100 nm. afterwards,
Polycarbonate substrate 1 on which adhesive layer 16 is interposed
I pasted 1 '.

Generally, when a thin film is irradiated with light, interference occurs due to the superposition of the reflected light from the front surface of the thin film and the reflected light from the back surface of the thin film. Therefore, when it is desired to increase the reflectance change of the super-resolution reading thin film, the effect of interference can be increased by providing a "reflection layer" that reflects light in the vicinity of the thin film. Note that an absorption layer that absorbs light may be used. The Al ₉₇ Ti ₃ layer 15 in FIG. 1 serves as this reflective layer.

In order to enhance the effect of interference, it is preferable to provide an "intermediate layer" between the super-resolution reading thin film and the reflective layer. The intermediate layer acts to prevent mutual diffusion between the super-resolution reading thin film and the reflective layer during super-resolution reading, and reduces heat escape to the reflective layer to improve read-out sensitivity. It has the function of crystallizing the film after super-resolution reading. In FIG. 12, (ZnS) ₈₀ (SiO ₂ ) ₂₀
Layer 14 acts as this intermediate layer.

At least one interface of the super-resolution reading thin film 13 is preferably protected by closely adhering to another substance, and it is more preferred that both interfaces are protected. This protection may be performed by the substrate or a protective layer formed separately from the substrate. The formation of the "protection layer" can prevent an increase in noise due to the deformation of the thin film at the time of super-resolution reading. The (ZnS) ₈₀ (SiO ₂ ) ₂₀ layer 12 in FIG. 12 acts as this protective layer.

The thickness of the super-resolution readout film 13 was determined from the measurement results of the reflectance in the crystallized state and the amorphous state shown in FIG. As shown in FIG. 2, when the film thickness is 30 nm, the reflectance in the crystallized state is larger than that in the amorphous state, and the difference in reflectance between the crystallized state and the amorphous state becomes maximum.
r ₄ Te ₅ ) ₂₀ (GeSb ₂ Te ₄ ) _{80 The} film 13 has a film thickness of 3
It was set to 0 nm.

The disk manufactured as described above was first initialized as follows. After pre-crystallization with flash light, the disk was rotated at 1800 rpm, the light intensity of the semiconductor laser was kept at a level (about 1 mW) at which super-resolution reading was not performed, and the light was condensed by the lens in the recording head. By irradiating the readout film 13 through the substrate 11 and detecting the reflectance, the head was driven so that the center of the light spot always coincided with the center of the tracking groove. While tracking like this,
Further, automatic focusing was performed so that the super-resolution readout film would be in focus, and first, for initial crystallization, continuous laser light having a power of 11 mW was irradiated 5 times on the same track. This irradiation power may be in the range of 9-18 mW. Then 6mW
The continuous laser light of was irradiated 3 times. This irradiation power is 4 ~
The range of 9 mW is sufficient. The above two types of irradiation may be performed once or more, but the irradiation with higher power is more preferably performed twice or more.

In a super-resolution readout film containing a high melting point component,
In order to improve the C / N, it is important to perform the initial crystallization sufficiently. For this reason, the initial crystallization is focused on irradiation with low power, and continuous laser light with power 6 mW is irradiated 500 times on the same track, followed by continuous laser light with 11 mW 3 times and continuous laser light with 6 mW. Irradiated 10 times. Although it takes time, when the laser irradiation of 6 mW 500 times and 11 mW 3 times was repeated several times, the C / N and the number of times super-resolution reading was possible further increased.

These irradiations are performed by a semiconductor laser array, a light beam from a gas laser is divided into a plurality of beams, or an elliptical beam obtained by shaping a light beam from a high-power gas laser or a semiconductor laser in the radial direction of the disk. If it is carried out at 1, it is possible to carry out at the same time for all tracks by one rotation of the disk. If a plurality of light spots are not arranged on the same track but are arranged at positions slightly displaced in the radial direction of the disc, a wide range can be initialized, and there is an effect that the unerased portion is reduced.

Further, at the end of the initialization, by irradiating the continuous laser beam while tracking between the grooves, the peripheral portion of the track was also crystallized, whereby the crosstalk could be reduced by 2 dB. Power of 6m for crystallization
It was set to W and irradiated with continuous light.

The principle of super-resolution readout by the super-resolution effect is as follows. In FIG. 8, 31 is a light spot such as a laser beam, and 32 a and 32 b are recording marks formed on the surface of the substrate 1. The light spot diameter is defined as the diameter of the light beam at the position where the light intensity becomes (1 / e ² ) of its peak intensity. The minimum pitch of the recording marks is set smaller than the spot diameter of the light spot 31.

In the high temperature region within the light spot, at least the phase change component GeSb ₂ Te _{4 in} the super-resolution readout film is melted and at least one of the real part n and the imaginary part k of the complex refractive index is lowered. A decrease in reflectance occurs. Therefore, two recording marks 32a, 3 are formed in the light spot 31.
Despite the presence of 2b, the recording mark 32b in the high temperature region 35 is hidden by the super-resolution readout layer 13, so that only the recording mark 32a is actually detected. In other words, the actual detection range 34 is, as shown in FIG. 8, the range 3 from the circular area of the light spot 31 which acts as a mask.
3, that is, a crescent-shaped region excluding the overlapping portion of the light spot 31 and the high temperature region 35. In this way, it becomes possible to perform super-resolution reading of recording marks smaller than the light spot diameter.

In the portion for performing super-resolution reading, the super-resolution reading was performed while keeping the laser power constant at 8 mW. This power depends on the melting point of the super-resolution readout film. After passing through the super-resolution readout area, the laser power was lowered to 1 mW and tracking and automatic focusing were continued. Reducing the laser power to 1 mW was effective in preventing the deterioration of the mask layer. Note that tracking and automatic focusing are continued during super-resolution reading. The relationship between the tracking and automatic focusing laser power Pt and the super-resolution readout laser power Pr was within the range shown by the following equation, and excellent super-resolution readout characteristics were obtained.

Pr / Pt ≧ 2 It was necessary to crystallize a disc in which the super-resolution readout film remains amorphous after the super-resolution readout.
Crystallization was not necessary for the disk having a film composition that was crystallized again after reading.

The C / N when super-resolution reading of marks of different sizes was compared between the disc using the super-resolution reading film of the present example and the disc not using the super-resolution reading film. As described above, the super-resolution effect of the minute mark was observed in the disc using the super-resolution readout film of this example.

Mark size (μm) Super-resolution readout Super-resolution readout With film (dB) Without film (dB) ──────────────────────── ──────── 0.3 30-0.4 43 30 0.5 0.5 47 35 0.6 0.6 49 40 0.7 50 46 0.8 50 50 50 For at least one of the protective film and the intermediate layer. Z used
Si-N-based material instead of nS-SiO _2, Si-O-
N-based material, SiO ₂ , SiO, TiO ₂ , Al ₂ O ₃ ,
_{Y 2 O 3, CeO, La} 2 O 3, In 2 O 3, GeO, Ge
O ₂ , PbO, SnO, SnO ₂ , Bi ₂ O ₃ , TeO ₂ ,
WO ₂ , WO ₃ , Sc ₂ O ₃ , ZrO ₂ and TaN, AlN,
Oxides and nitrides of Al—Si—N based materials such as AlSiN ₂ and Si ₃ N ₄ , ZnS, Sb ₂ S ₃ , CdS, I
n ₂ S ₃ , Ga ₂ S ₃ , GeS, SnS ₂ , PbS, Bi ₂ S
Sulfides such as ₃ , SnSe ₂ , Sb ₂ Se ₃ , CdS
e, ZnSe, In ₂ Se ₃ , Ga ₂ Se ₃ , GeSe, G
selenides such as eSe ₂ , SnSe, PbSeBi ₂ Se ₃ , fluorides such as CeF ₃ , MgF ₂ , CaF ₂ , or Si, Ge, TiB ₂ , B ₄ C, B, C, or all of the above mentioned You may use the thing of a composition close to the material for protective films. Further, it can be formed of a fluororesin such as an acrylic resin, a polycarbonate, a polyolefin, an epoxy resin, a polyimide, a polystyrene, a polyethylene, a polyethylene terephthalate, a polytetrafluoroethylene (Teflon), or the like. Ethylene-known as hot melt adhesive-vinyl acetate copolymer, etc.,
An adhesive or the like may be used. You may form with the ultraviolet curing resin which has at least 1 of these resins as a main component. The organic substrate may also serve as the protective layer. Alternatively, they may be mixed material layers or multiple layers. When the intermediate layer was omitted, the super-resolution reading sensitivity was reduced by about 30%, and the number of times super-resolution reading was possible also decreased. The refractive index of the intermediate layer is 1.7.
In the range of 2.3 to 2.3, the film thickness is 3 nm to 400n
A C / N of 48 dB or more was obtained in the range of m or less.

Instead of Al—Ti used for the reflective layer, A
u, Ag, Cu, C, Si, Ge, Al, Ni, Fe,
Co, Cr, Ti, Pd, Pt, W, Ta, Mo, Sb
Or a layer of an alloy, a compound, a mixture or a mixture of these alloys containing these as the main components, or a multi-layer,
A composite layer of these and another substance such as an oxide may be used.

As the substrate, instead of the polycarbonate substrate having the unevenness such as the tracking guide directly formed on the surface, polyolefin, epoxy, acrylic resin, or chemically strengthened glass having the ultraviolet curable resin layer formed on the surface may be used.

Although the disk using the super-resolution readout film shown in FIG. 13 has a single-sided structure, two same structures as 11 to 15 were prepared instead of the polycarbonate substrate 11 ′, and the adhesive layer 6 was used. It may be a double-sided structure in which they are bonded together.

[Embodiment 8] In the disk shown in FIG. 1, the composition of the super-resolution readout film was changed as follows. The extinction coefficient k of the super-resolution readout film before and after irradiation with laser light was The amount of change Δk ′ of has changed. A recording mark having a length of about 25% of the diameter of the light spot was formed on a disc equipped with these super-resolution readout films, and the C / N of reproduced signals after 10 ⁵ super-resolution readouts were compared. As a result, the following results were obtained.

Amount of change in extinction coefficient k of film composition C / N of reproduced signal after 10 ⁵ times super-resolution readout ─────────────────────── ────────────── (Cr ₄ Te ₅ ) ₈₀ (GeSb ₂ Te ₄ ) ₂₀ △ k '= 5% 37 dB (Cr ₄ Te ₅ ) ₆₀ (GeSb ₂ Te ₄ ) ₄₀ △ k ′ = 10% 42 dB (Cr ₄ Te ₅ ) ₄₀ (GeSb ₂ Te ₄ ) ₆₀ Δk ′ = 20% 46 dB (Cr ₄ Te ₅ ) ₂₀ (GeSb ₂ Te ₄ ) ₈₀ Δk ′ = 30% 48 dB This result From this, it is understood that the range of 20% ≦ Δk ′ is preferable.

[Embodiment 9] When the high melting point component was put in the super resolution reading film, the number of times super resolution reading was possible was improved. At this time, the difference in the number of times super-resolution reading was possible due to the difference in melting point (Δm.p = melting point of high melting point component−melting point of phase change component) in the super resolution reading film was examined. Here, the phase change component is Ge
The high melting point component was changed using Sb ₂ Te ₄ .

High melting point component Δm. p (℃) Number of times super resolution can be read (times) ────────────────────────────────── Pt ₃ Sb 50 5 x 10 ⁵ Mo ₃ Sb ₇ 150 1 × 10 ⁶ CoSb ₃ 200 2 × 10 ⁶ Cr ₄ Te ₅ ≧ 300 ≧ 2 × 10 ^{6 From} this result, Δm. It can be seen that the range of p ≧ 150 is preferable.

Example 10 In the super-resolution read film described in Example 7, the phase change component other than GeSb ₂ Te ₄ was at least one of the following group D, or a composition close to this, or A compound having a melting point of 650 ° C. or lower,
Similar results can be obtained by substituting at least one of the compounds having a composition close to that or a mixed composition or a compound of three or more elements close to the mixed composition.

<Group D> Sn, Pb, Sb, Te, Zn,
Cd, Se, In, Ga, S, Tl, Mg, Tl ₂ S
e, TlSe, Tl ₂ Se ₃ , Tl ₃ Te ₂ , TlTe,
InBi, In ₂ Bi, TeBi, Tl-Se, Tl-
Te, Pb-Sn, Bi-Sn, Se-Te, SS
e, Bi-Ga, Sn-Zn, Ga-Sn, Ga-I
n, In ₃ SeTe ₂ , AgInTe ₂ , GeSb ₄ Te
₇ , Ge ₂ Sb ₂ Te ₅ , GeSb ₂ Te ₄ , GeBi ₄ T
e ₇ , GeBi ₂ Te ₄ , Ge ₃ Bi ₂ Te ₆ , Sn ₂ Sb
₆ Se ₁₁ , Sn ₂ Sb ₂ Se ₅ , SnSb ₂ Te ₄ , Pb ₂
Sb ₆ Te ₁₁ , CuAsSe ₂ , Cu ₃ AsSe ₃ , Cu
SbS ₂ , CuSbSe ₂ , InSe, Sb ₂ Se ₃ ,
Sb ₂ Te ₃ , Bi ₂ Te ₃ , SnSb, FeTe, Fe
₂ Te ₃ , FeTe ₂ , ZnSb, Zn ₃ Sb ₂ , VTe
₂ , V ₅ Te ₈ , AgIn ₂ , BiSe, InSb, I
n ₂ Te, In ₂ Te ₅ , Ba ₄ Tl, Cd ₁₁ Nd, Ba
₁₃ Tl, Cd ₆ Nd, Ba ₂ Tl.

As the high melting point component other than Cr ₄ Te ₅ ,
Similar results can be obtained by substituting at least one of the following compounds, alloys, or compounds having a composition close to that, or a mixed composition thereof or a compound of three or more elements close to the mixed composition.

(A) The melting point of the phase change component is 450 to 650.
When the temperature is ° C, the compound of the following group A or the compound having a melting point of 800 ° C or higher

<Group A> BaPd ₂ , BaPd ₅ , NdP
d, NdPd ₃ , NdPd ₅ , Nd ₇ Pt ₃ , Nd ₃ Pt
₂ , NdPt, Nd ₃ Pt ₄ , NdPt ₂ , NdP
t ₅ , Bi ₂ Nd, BiNd, Bi ₃ Nd ₄ , Bi ₃ Nd
₅ , BiNd ₂ , Cd ₂ Nd, CdNd, Mn ₂ Nd, M
n ₂₃ Nd ₆ , Mn ₁₂ Nd, Nd ₅ Sb ₃ , Nd ₄ Sb ₃ ,
NdSb, NdSb ₂ , Fe ₂ Nd, Fe ₁₇ Nd ₂ , C
s ₃ Ge ₂ , CsGe, CsGe ₄ , Nd ₅ Si ₃ , Nd
₅ Si ₄ , NdSi, Nd ₃ Si ₄ , Nd ₂ Si ₃ , Nd ₅
Si ₉ , Cs ₂ Te, NdTe ₃ , Nd ₂ Te ₅ , NdT
e ₂ , Nd ₄ Te ₇ , Nd ₂ Te ₃ , Nd ₃ Te ₄ , Nd
Te, Ce ₃ Ir, Ce ₂ Ir, Ce ₅₅ Ir ₄₅ , CeIr
₂ , CeIr ₃ , Ce ₂ Ir ₇ , CeIr ₅ , CaPd,
CaPd ₂ , CaGe, Ca ₂ Ge, GeNa ₃ , Ge
Na, CaSi ₂ , Ca ₂ Si, CaSi, Se ₂ Sr,
Se ₃ Sr ₂ , SeSr, GeSr ₂ , GeSr, Ge _{2
Sr, SnSr, Sn 3 Sr 5} , SnSr 2, Ce 2 T
1, Ce ₅ Tl ₃ , CeTl ₃ , Ce ₃ Tl ₅ , CeT
1, BaTl, Pd ₁₃ Tl ₉ , Pd ₂ Tl, Pd ₃ Tl,
Mg ₂ Si, Mg ₂ Ge, BaPd ₂ , BaPd ₅ , Ce
₄ Se ₇ , Ce ₃ Se ₄ , Ce ₂ Se ₃ , CeSe, Ce ₅
Ge ₃ , Ce ₄ Ge ₃ , Ce ₅ Ge ₄ , CeGe, Ce ₃ G
e ₅ , Ce ₅ Si ₃ , Ce ₃ Si ₂ , Ce ₅ Si ₄ , Ce
Si, Ce ₃ Si ₅ , CeSi ₂ , CeTe ₃ , Ce ₂ T
e ₅ , CeTe ₂ , Ce ₄ Te ₇ , Ce ₃ Te ₄ , CeT
e, La ₃ Se ₇ , LaSe ₂ , La ₄ Se ₇ , La ₂ S
e ₃ , La ₃ Se ₄ , LaSe, GeLa ₃ , Ge ₃ La
₅ , Ge ₃ La ₄ , Ge ₄ La ₅ , GeLa, Ge ₅ La
₃ , BaSe ₂ , Ba ₂ Se ₃ , BaSe, PdSe, M
o ₃ Se ₄ , MoSe ₂ , Ba ₂ Ge, BaGe ₂ , Ba
Ge, Ba ₂ Te ₃ , BaTe, Ge ₂ Pd ₅ , GeP
d ₂ , Ge ₉ Pd ₂₅ , GePd, Ge ₃ Pt, Ge ₃ P
t ₂ , GePt, Ge ₂ Pt ₃ , GePt ₂ , GePt
₃ , Pu ₃ Sn, Pu ₅ Sn ₃ , Pu ₅ Sn ₄ , Pu ₈ Sn
₇ , Pu ₇ Sn ₈ , PuSn ₂ , PuSn ₃ , Pt ₅ Te
₄ , Pt ₄ Te ₅ , PtTe ₂ , GeNi, Ge ₃ N
i ₅ , Ge ₂ Ni ₅ , GeNi ₃ , NiTe _0.85 , Ni
Te _0.775 , Ni ₃ ± _x Te _x , Cr ₁₁ Ge ₁₉ , CrG
e, Cr ₁₁ Ge ₈ , Cr ₅ Ge ₃ , Cr ₃ Ge, CrSi
₂ , Cr ₅ Si ₃ , Cr ₃ Si, Cr ₅ Te ₈ , Cr ₄ Te
₅ , Cr ₃ Te ₄ , Cr _1-x Te, Ge ₃ Mn ₅ , GeM
n ₂ , Mn ₆ Si, Mn ₉ Si ₂ , Mn ₃ Si, Mn ₅ Si
₂ , Mn ₅ Si ₃ , MnSi, Mn ₁₁ Si ₁₉ , Mn ₂ S
n, Mn _3.25 Sn, MnTe, Te ₂ W, FeGe ₂ ,
Fe ₅ Ge ₃ , Fe ₃ Ge, Fe ₂ Si, Fe ₅ Si ₃ , F
eSi, FeSi ₂ , Ge ₂ Mo, Ge ₄₁ Mo ₂₃ , Ge
₁₆ Mo ₉ , Ge ₂₃ Mo ₁₃ , Ge ₃ Mo ₅ , GeMo ₃ , M
o ₃ Si, Mo ₅ Si ₃ , MoSi ₂ , MoSn, MoS
n ₂ , Mo ₃ Te ₄ , MoTe ₂ , Si ₂ Ti, SiT
i, Si ₄ Ti ₅ , Si ₃ Ti ₅ , SiTi ₃ , Sn ₅ Ti
₆ , Sn ₃ Ti ₅ , SnTi ₂ , SnTi ₃ , CoGe
₂ , Co ₅ Ge ₇ , CoGe, Co ₅ Ge ₃ , Co ₄ G
e, Co ₃ Te ₄ , Ge ₇ Re ₃ , Re ₅ Si ₃ , ReS
i, ReSi ₂ , Re ₂ Te.

(B) The melting point of the phase change component is 250 to 450.
When the temperature is ℃, the compound of Group A or the following Group B, or melting point 600
Compound above ℃.

<Group B> Cs ₃ Ge, Ba ₂ Tl, GePd
₃ , Fe ₆ Ge ₅ , FeTe ₂ , Co ₅ Ge ₂ , Nd ₃ P
d, Cs ₃ Te ₂ , Ce ₄ Ir, NaPd, Ca ₉ Pd,
Ca ₃ Pd ₂ , Ca ₂ Ge, Se ₃ Sr, Ce ₃ Tl, Ce
Se ₂ , Ce ₃ Ge, BaSe ₃ , GeSe ₂ , GeS
e, BaTe ₂ , GePd ₅ , Ge ₈ Mn ₁₁ , MnTe
₂ , Ge ₃ W ₂ , FeGe, Fe ₄ Ge ₃ , Fe ₃ Sn,
_{Fe 3 Sn 2, FeSn, CoTe} 2.

(C) When the melting point of the phase change component is 250 ° C. or less, the compound of Group A, Group B or Group C below, or the compound having a melting point of 400 ° C. or more.

<Group C> Ba ₄ Tl, CsTe, Ba ₄ T
1, Ba ₁₃ Tl, Cd ₁₁ Nd, Cd ₆ Nd, Cs ₅ T
e ₄ , Ca ₃ Pd, Ca ₅ Pd ₂ , Sn ₃ Sr, Ba ₁₃ T
1, PdTl ₂ , FeSe ₂ , FeSe, Cr ₂ Te ₃ ,
CrTe ₃ , FeSn ₂ .

[Embodiment 11] In the super-resolution readout film, when the combination of the high melting point component and the phase change component is Cr,
_{The combination of 4} Te ₅ and GeSb ₂ Te ₄ in which the same element is present in each component had excellent super-resolution readout characteristics. However, if the amount of the same element is too large, the difference in melting point between both components will not be satisfied, so the amount of the same element is preferably 80 atomic% or less in the components. Further, when the amount is small, the refractive index of both components in the aperture portion often does not become equal, and 30 atomic% or more is preferable.

[Embodiment 12] GeSb ₂ Te ₄ as a phase change component and Cr as a high melting point component in the super-resolution readout film.
_{When 4} C ₅ was used and the content of the high melting point component (atomic%) was varied to examine the C / N and the number of times super-resolution reading was possible, the following results were obtained.

Content of high melting point component (atomic%) Number of times of super-resolution readout (times) ────────────────────────────── ── 5 6 × 10 ⁵ 10 1 x 10 ⁶ 20 2 x 10 ⁶ ≧ 30 ≧ 2 × 10 ⁶ Content of high melting point component (%) C / N (dB) ───────────────────────── ≦ 30 ≧ 48 40 40 48 50 46 46 60 42 The results show that the content of the high melting point component is preferably in the range of 10 to 50%, more preferably in the range of 20 to 40%.

Oxides, sulfides, nitrides in the high melting point component,
The content of carbides is preferably less than 50% of the high melting point component, particularly preferably less than 20%. If the content of these components is large, the difference in complex index of refraction from the phase change component cannot be reduced, or oxygen or the like diffuses into the phase change component to deteriorate the super-resolution readout characteristics.

[Embodiment 13] Since the melting point of the super-resolution readout film differs depending on the super-resolution readout film material, the optimum super-resolution readout power was examined by changing the composition of the phase change component. became. Cr ₄ Te ₅ as high melting point component
Was used.

Composition of Phase Change Components in Film Melting Point of Film (° C.) Super Resolution Readout Power (mW) ────────────────────────── ─────────── Sn ₇₅ Zn ₂₅ 250 3 In ₂ Te ₅ 450 6 Ge ₂ Sb ₂ Te ₅ 650 8 Super-resolution readout film with lower melting point Is low, which is preferable.

[Embodiment 14] When the number of revolutions is constant, the linear velocities of the inner circumference and the outer circumference of the disk are different. With a 5 inch disc, the linear velocity changes from 5.7 to 11.3 m / s,
Correspondingly, when the super-resolution readout film thickness is changed so as to be 20 nm at the inner circumference and 40 nm at the outer circumference, the width of the unmasked region of the light spot becomes smaller toward the inner circumference and In both cases, excellent super-resolution readout characteristics of C / N 48 dB were obtained. Moreover, when the amount of deviation from the GeSbTe-based GeSb ₂ Te ₄ or Ge ₂ Sb ₂ Te ₅ composition is reduced from the inner circumference to the outer circumference, the crystallization speed becomes faster toward the outer circumference, so it is easy to handle linear velocity. C / N on both the inner and outer circumferences
A good super-resolution readout characteristic of 48 dB was obtained.

[Embodiment 15] FIG. 14 shows a block diagram of a super-resolution reading system of a super-resolution reading device. Upon receiving the super-resolution read command 42, laser irradiation is performed from the optical head 50, and the reflected light returned from the optical disc 51 is detected again by the optical head 50.

When continuous light is used as the laser light, the system of (a) in the figure is used, and when pulsed light is used, the pulse forming circuit 43 is incorporated into the system of (b). The synchronization of the pulsed light is performed through the address section / flag section detection 45.

In order to obtain good super-resolution readout characteristics,
The laser power setting circuit 47 maintains the relationship between the laser power Pt for tracking and automatic focusing and the laser power Pr for super-resolution reading as in the following equation.

Pr / Pt ≧ 2 Further, in order to prevent the high melting point component from staying in the solid phase without melting the entire film even in the region where the temperature of the super resolution reading film reaches the maximum temperature, the return light is reflected during laser power irradiation. The light intensity distribution analysis circuit 48 detects and analyzes the disturbance of the light intensity distribution, and a circuit capable of adjusting the laser power according to the magnitude of the disturbance is incorporated in the laser power setting circuit 47. As a result, deterioration of the super-resolution readout film is less likely to occur.

Here, the turbulence of the light intensity distribution means the temporal variation of the turbulence of the light intensity distribution, that is, the temporal variation of the ratio of each detector output. Distortion of light intensity distribution is one-dimensional,
Alternatively, two or more two-dimensionally arranged detectors arranged substantially parallel to the recording medium surface were used, and the output of each detector was connected to the light intensity distribution analysis circuit 48 for detection.

In order to prevent deterioration of the super-resolution reading film, the super-resolution reading laser light is pulsed light. At this time, the ratio (a: λ / NA) of the laser spot diameter (λ / NA) and the length a of the center portion of the aperture in the track direction is ⅓ to
A disc that can be halved and has minute marks, 0.4λ
It was found that the spots overlap by 30% or more in the range of / NA ≦ vT, so that the effect of pulsing is small, and the mark is skipped in the range of vT ≦ 1.5λ / NA.

Therefore, in order to surely perform super-resolution reading of the mark, a circuit for satisfying the following expression is incorporated in the pulse conversion circuit 43 of FIG.

0.4λ / NA ≦ vT ≦ 1.5λ / NA 0.3k ≦ x / T ≦ 0.5k As a result, C / N of 46 dB could be obtained. k is a proportional constant, and k = 1 when the laser power is 8 mW and the linear velocity is 8 m / s in the disk having the structure of FIG. further,
When the following formula was satisfied, C / N was improved by 2 dB.

0.5λ / NA ≦ vT ≦ 0.9λ / NA 0.3k ≦ x / T ≦ 0.5k [Embodiment 16] FIG. 9 is a read / write disk using the super-resolution readout film of the present invention. 2 is an example of a structural cross-sectional view of FIG. In this example, the super-resolution readout film having the average composition of the general formula (8) was used.

First, a polycarbonate substrate having a diameter of 13 cm and a thickness of 1.2 mm was formed. Next, the substrate can be formed sequentially laminated film comprising a plurality of targets, also, the film thickness uniformity, attached to good reproducibility magnetron sputtering in the device, (ZnS) having a thickness of 125nm on the _80
20 layers of (SiO ₂ ) were formed. Then, (Sn ₃ Zn)
₈₀ (SnTi ₂ ) ₂₀ film 30 nm, (ZnS) ₈₀ (Si
O ₂ ) ₂₀ layer, (Cr ₄ Te ₅ ) ₂₀ (GeSb ₂ Te ₄ ) ₈₀
The film was formed to 30 nm. Next, (ZnS) ₈₀ (SiO ₂ )
₂₀ layers of 20 nm and Al-Ti layers of 100 nm were sequentially laminated. After that, a polycarbonate substrate was bonded onto this via an adhesive layer. This disc can be used on only one side, but two discs having the same structure may be prepared and a double-sided structure may be used in which an adhesive layer is laminated.

In the portion for performing super-resolution reading, the laser power was set to 3 mW and super-resolution reading was performed. This power depends on the melting point of the super-resolution readout film. After passing through the super-resolution readout area, the laser power was lowered to 1 mW and tracking and automatic focusing were continued. Note that tracking and automatic focusing are continued during super-resolution reading.

After the super-resolution reading, the super-resolution reading film was crystallized again, so that crystallization was not necessary.

[Embodiment 17] In the super-resolution readout film made of (Sn ₃ Zn) ₈₀ (SnTi ₂ ) ₂₀ shown in FIG. 9 of Embodiment 16, Sn and Ti are maintained while keeping the Zn content constant. When the content of C is changed, the number of possible super-resolution readings and C of the reproduced signal after 10 ⁵ super-resolution readings
/ N changed as follows.

Composition Super-Resolution Readable Number of Times ─────────────────────────── Sn ₅₅ Zn ₂₀ Ti ₂₅ ＞ 2 × 10 ⁶ times Sn ₆₇ Zn ₂₀ Ti ₁₃ 2 × 10 ⁶ times Sn ₇₅ Zn ₂₀ Ti ₅ 1 × 10 ⁶ times Sn ₈₀ Zn ₂₀ 5 × 10 ⁵ times Composition 10 ⁵ times C / N of reproduced signal after super-resolution reading ── ────────────────────────────────── Sn ₂₅ Zn ₂₀ Ti ₅₅ 44dB Sn ₃₀ Zn ₂₀ Ti ₅₀ 46dB Sn ₄₀ Zn ₂₀ Ti ₄₀ 48 dB Sn ₅₅ Zn ₂₀ Ti ₂₅ 50 dB From this, the range of e and f in the general formula (8) is 3
0 ≦ e ≦ 95, 5 ≦ f ≦ 50 are preferable, and 40 ≦ e ≦ 8
It can be seen that 7, 13 ≦ f ≦ 40 is more preferable.

Furthermore, the above (Sn ₃ Zn) ₈₀ (SnT
i ₂ ) _{20 in the} super-resolution readout film 26, S
When Tl was added while keeping the contents of n, Zn and Ti constant and the contents were changed as follows, the C / N of the reproduced signal after 10 ⁵ times super-resolution reading was as follows: Has changed.

Tl content C / N of reproduced signal after 10 ⁵ times super-resolution reading ────────────────────────────── ───── g = 0% 46dB g = 10% 48dB g = 20% 46dB g = 25% 43dB Therefore, the range of g in the general formula (8) is 0 ≦ g.
It can be seen that ≦ 20 is preferable and 0 ≦ g ≦ 10 is more preferable.

Further, the above D and D '(the above D is the above Sn,
In the case of D and D'2 elements such as Zn), E and F, whether the high melting point component formed by the combination of D-E, E-F and D'-E has no eutectic point, Even if it had a eutectic point, it was preferable that the melting point was 150 ° C. or higher than the melting points of D and DD ′.

[Embodiment 18] Sn-Z of Embodiment 16
The super-resolution readout film made of n-Ti is formed of a material having an average composition represented by the general formula (8), Pb-Se, Pb-.
Ce, Pb-La, Pb-Pt, Pb-Si, Sn-S
b, Sn-Se, Sn-Co, Sn-Cu, Sn-N
i, Sn-Pt, Bi-Te, Bi-Se, Bi-C
e, Bi-Cu, Bi-Cd, Bi-Pt, Zn-N
i, Zn-Pt, Zn-La, Zn-Ce, Ga-C
r, Ga-Cu, Ga-Ni, Ga-La, Ga-P
t, Ga-Ce, In-Se, In-Sb, In-T
e, In-As, In-Mn, In-Ni, In-A
g, Pb-Sn-Se, Pb-Sn-Ce, Pb-Sn
-La, Pb-Sn-Pt, Pb-Sn-Si, Pb-
Sn-Sb, Pb-Sn-Co, Pb-Sn-Cu, P
b-Sn-Ni, Sn-Bi-Sb, Sn-Bi-S
e, Sn-Bi-Co, Sn-Bi-Cu, Sn-Bi
-Ni, Sn-Bi-Pt, Sn-Bi-Te, Sn-
Bi-Ce, Sn-Bi-Cd, Zn-Sn-Sb, Z
n-Sn-Se, Zn-Sn-Co, Zn-Sn-C
u, Zn-Sn-Ni, Zn-Sn-Pt, Zn-Sn
-Ni, Zn-Sn-La, Zn-Sn-Ce, Sn-
Ga-Sb, Sn-Ga-Se, Sn-Ga-Co, S
b-Ga-Cu, Sn-Ga-Ni, Sn-Ga-P
t, Sn-Ga-Cr, Sn-Ga-La, Sn-Ga
-Ce, Bi-Ga-Te, Bi-Ga-Se, Bi-
Ga-Cu, Bi-Ga-Cd, Bi-Ga-Pt, B
i-Ga-Cr, Bi-Ga-Ni, Bi-Ga-L
a, Bi-Ga-Ce, In-Ga-Cr, In-Ga
-Cu, In-Ga-Ni, In-Ga-La, In-
Ga-Pt, In-Ga-Ce, In-Ga-Se, I
n-Ga-Sb, In-Ga-Te, In-Ga-A
s, In-Ga-Mn, In-Ga-Ag, In-Bi
-Te, In-Bi-Se, In-Bi-Cu, In-
Bi-Cd, In-Bi-Pt, In-Bi-Sb, I
n-Bi-As, In-Bi-Mn, In-Bi-N
Similar results were obtained even when i, In-Bi-Ag, In-Bi-Ce, or the like was changed.

[Example 19] (Sn _{3 of} Example 16)
The super-resolution readout film made of Zn) ₈₀ (SnTi ₂ ) ₂₀ is formed of a material having an average composition represented by the general formula (11), for example, Se ₅₁ In ₄₀ Cr ₉ (high melting point component Cr ₃ Se ₄ ; Similar results can be obtained by changing the change component; InSe). However, the number of read times is 2 × 10 ⁶ times or more, and the C / N of the reproduced signal after 10 ⁵ times super-resolution reading is 4
In the general formula (11), p, q. r,
The range of s is 40 ≦ p ≦ 95, 0 ≦ q ≦ 55, 5 ≦ r ≦
50 and 0 ≦ s ≦ 20. A more preferable range of C / N of 48 dB or more is 50 ≦ p ≦ 80, 0 ≦ q ≦ 4.
The values were 0, 10 ≦ r ≦ 40, and 0 ≦ s ≦ 10. This composition could also be used as the phase change recording film 28. It can also be used as a phase change recording film of a recording medium that does not use a super-resolution readout film.

[Embodiment 20] Se-I of Embodiment 19
A super-resolution readout film made of n-Cr is formed of a material having an average composition represented by the general formula (2), Se-In-Si,
Se-In-Ag, Se-In-Al, Se-In-B
a, Se-In-Ca, Se-In-Cd, Se-In
-Co, Se-In-Cu, Se-In-Mg, Se-
In-Mn, Se-In-Mo, Se-In-Ni, S
e-In-Pd, Se-In-Pt, Se-In-T
a, Se-In-Ti, Se-In-V, Se-In-
W, Se-In-Y, Se-In-Pb, Se-Sb-
Si, Se-Sb-Ag, Se-Sb-Al, Se-S
b-Ba, Se-Sb-Ca, Se-Sb-Cd, Se
-Sb-Co, Se-Sb-Cr, Se-Sb-Cu,
Se-Sb-Mg, Se-Sb-Mn, Se-Sb-M
o, Se-Sb-Ni, Se-Sb-Pd, Se-Sb
-Pt, Se-Sb-Ta, Se-Sb-Ti, Se-
Sb-V, Se-Sb-W, Se-Sb-Y, Se-S
b-Pb, Se-Bi-Si, Se-Bi-Ag, Se
-Bi-Al, Se-Bi-Ba, Se-Bi-Ca,
Se-Bi-Cd, Se-Bi-Co, Se-Bi-C
r, Se-Bi-Cu, Se-Bi-Mg, Se-Bi
-Mn, Se-Bi-Mo, Se-Bi-Ni, Se-
Bi-Pd, Se-Bi-Pt, Se-Bi-Ta, S
e-Bi-Ti, Se-Bi-V, Se-Bi-W, S
e-Bi-Y, Se-Bi-Pb, Se-Te-Si,
Se-Te-Ag, Se-Te-Al, Se-Te-B
a, Se-Te-Ca, Se-Te-Cd, Se-Te
-Co, Se-Te-Cr, Se-Te-Cu, Se-
Te-Mg, Se-Te-Mn, Se-Te-Mo, S
e-Te-Ni, Se-Te-Pd, Se-Te-P
t, Se-Te-Ta, Se-Te-Ti, Se-Te
-V, Se-Te-W, Se-Te-Y, Se-Te-
Pb, Se-Au-Si, Se-Au-Ag, Se-A
u-Al, Se-Au-Ba, Se-Au-Ca, Se
-Au-Cd, Se-Au-Co, Se-Au-Cr,
Se-Au-Cu, Se-Au-Mg, Se-Au-M
n, Se-Au-Mo, Se-Au-Ni, Se-Au
-Pd, Se-Au-Pt, Se-Au-Ta, Se-
Au-Ti, Se-Au-V, Se-Au-W, Se-
Au-Y, Se-Au-Pb, Se-B-Si, Se-
B-Ag, Se-B-Al, Se-B-Ba, Se-B
-Ca, Se-B-Cd, Se-B-Co, Se-B-
Cr, Se-B-Cu, Se-B-Mg, Se-BM
n, Se-B-Mo, Se-B-Ni, Se-BP
d, Se-B-Pt, Se-B-Ta, Se-B-T
i, Se-B-V, Se-B-W, Se-B-Y, Se
-B-Pb, Se-Cs-Si, Se-Cs-Ag, S
e-Cs-Al, Se-Cs-Ba, Se-Cs-C
a, Se-Cs-Cd, Se-Cs-Co, Se-Cs
-Cr, Se-Cs-Cu, Se-Cs-Mg, Se-
Cs-Mn, Se-Cs-Mo, Se-Cs-Ni, S
e-Cs-Pd, Se-Cs-Pt, Se-Cs-T
a, Se-Cs-Ti, Se-Cs-V, Se-Cs-
W, Se-Cs-Y, Se-Cs-Pb, Se-Sn-
Si, Se-Sn-Ag, Se-Sn-Al, Se-S
n-Ba, Se-Sn-Ca, Se-Sn-Cd, Se
-Sn-Co, Se-Sn-Cr, Se-Sn-Cu,
Se-Sn-Mg, Se-Sn-Mn, Se-Sn-M
o, Se-Sn-Ni, Se-Sn-Pd, Se-Sn
-Pt, Se-Sn-Ta, Se-Sn-Ti, Se-
Sn-V, Se-Sn-W, Se-Sn-Y, Se-S
n-Pb, Se-Tl-Si, Se-Tl-Ag, Se
-Tl-Al, Se-Tl-Ba, Se-Tl-Ca,
Se-Tl-Cd, Se-Tl-Co, Se-Tl-C
r, Se-Tl-Cu, Se-Tl-Mg, Se-Tl
-Mn, Se-Tl-Mo, Se-Tl-Ni, Se-
Tl-Pd, Se-Tl-Pt, Se-Tl-Ta, S
e-Tl-Ti, Se-Tl-V, Se-Tl-W, S
e-Tl-Y, Se-Tl-Pb, Se-S-Si, S
e-S-Ag, Se-S-Al, Se-S-Ba, Se
-S-Ca, Se-S-Cd, Se-S-Co, Se-
S-Cr, Se-S-Cu, Se-S-Mg, Se-S
-Mn, Se-S-Mo, Se-S-Ni, Se-S-
Pd, Se-S-Pt, Se-S-Ta, Se-S-T
i, Se-S-V, Se-S-W, Se-S-Y, Se
-S-Pb, Se-Ge-Si, Se-Ge-Ag, S
e-Ge-Al, Se-Ge-Ba, Se-Ge-C
a, Se-Ge-Cd, Se-Ge-Co, Se-Ge
-Cr, Se-Ge-Cu, Se-Ge-Mg, Se-
Ge-Mn, Se-Ge-Mo, Se-Ge-Ni, S
e-Ge-Pd, Se-Ge-Pt, Se-Ge-T
a, Se-Ge-Ti, Se-Ge-V, Se-Ge-
W, Se-Ge-Y, Se-Ge-Pb, Se-Fe-
Si, Se-Fe-Ag, Se-Fe-Al, Se-F
e-Ba, Se-Fe-Ca, Se-Fe-Cd, Se
-Fe-Co, Se-Fe-Cr, Se-Fe-Cu,
Se-Fe-Mg, Se-Fe-Mn, Se-Fe-M
o, Se-Fe-Ni, Se-Fe-Pd, Se-Fe
-Pt, Se-Fe-Ta, Se-Fe-Ti, Se-
Fe-V, Se-Fe-W, Se-Fe-Y, Se-F
e-Pb, Se-Zn-Si, Se-Zn-Ag, Se
-Zn-Al, Se-Zn-Ba, Se-Zn-Ca,
Se-Zn-Cd, Se-Zn-Co, Se-Zn-C
r, Se-Zn-Cu, Se-Zn-Mg, Se-Zn
-Mn, Se-Zn-Mo, Se-Zn-Ni, Se-
Zn-Pd, Se-Zn-Pt, Se-Zn-Ta, S
e-Zn-Ti, Se-Zn-V, Se-Zn-W, S
Similar results were obtained even when changing to e-Zn-Y, Se-Zn-Pb, or the like.

[Embodiment 21] FIG. 7 shows a cross section of a read-only disc-shaped information recording medium in which information is engraved with uneven bits on the surface of a substrate.

In this disc-shaped medium, bits are formed on the surface of the substrate, and the recording film is used as the mask layer 1.
The points used as 3, 13 'are only different from the disk-shaped medium of Example 1, and the other configurations are the same.

That is, a film thickness of about 125 n is formed on the polycarbonate substrate 11 or 11 'having information bits on the surface.
m protective layer 1 composed of (ZnS) ₈₀ (SiO ₂ ) ₂₀ film
2, 12 ′ are formed respectively, and an island-shaped Ag ₂ Te film (not shown) having an average film thickness of 3 nm and a ((Ag ₂ Te film having a film thickness of about 30 nm are formed on the protective layer 12, 12 ′ in this order. ) ₃₀ (S
e ₈₀ −Te ₂₀ ) _70, that is, mask layers 13 and 13 ′ having a composition of Ag ₂₀ Te ₂₄ Se ₅₆ , and (ZnS) having a film thickness of about 25 nm.
Intermediate layers 14, 14 'made of ₈₀ (SiO ₂ ) ₂₀ film and reflective layers 15, 1 made of Al ₉₇ Ti ₃ film having a film thickness of 80 nm
5'are formed respectively. Reflective layer 15, 15 '
The two are bonded to each other by a vinyl chloride / vinyl acetate-based hot melt adhesive layer 16. The laser light for reading is incident from the substrate side. Mask layer 13, 1
In 3 ′, the high melting point component Ag ₂ Te was deposited in the same form as in Example 1 (see FIG. 1), and the remaining component (FIG. 1) was deposited.
(Corresponding to the phase change component 3a in) is (Se ₈₀ −
Te ₂₀ ).

(Other Examples of High Melting Point Component) Mask Layers 13, 1
As the high melting point component precipitated in 3 ', other than Ag ₂ Te, those described in Examples 1 and 3 can be used. The formation of the island-shaped Ag ₂ Te film may be omitted.

(Another Example of Residual Component After Precipitation of High Melting Point Component) Part or all of Se ₈₀ -Te ₂₀ which is the residual component other than the high melting point component is replaced with Sn, Pb, Sb, Bi, Te, Zn, Cd,
Se, In, Ga, S, Tl, Mg, Tl ₂ Se, Tl
Se, Tl ₂ Se ₃ , Tl ₃ Te ₂ , TlTe, InBi,
_{In 2 Bi, TeBi, Tl-} Se, Tl-Te, Pb
-Sn, Bi-Sn, Se-Te, S-Se, Bi-G
a, Sn-Zn, Ga- Sn, Ga-In, In 3 Se
Te ₂ , AgInTe ₂ , GeSb ₄ Te ₇ , Ge ₂ Sb ₂ T
e ₅ , GeSb ₂ Te ₄ , GeB ₄ Te ₇ , GeBi ₂ T
e ₄ , Ge ₃ Bi ₂ Te ₆ , Sn ₂ Sb ₆ Se ₁₁ , Sn ₂ Sb ₂
Se ₅ , SnSb ₂ Te ₄ , Pb ₂ Sb ₆ Te ₁₁ , CuAs
Se ₂ , Cu ₃ AsSe ₃ , CuSbS ₂ , CuSbS
e ₂ , InSe, Sb ₂ Se ₃ , Sb ₂ Te ₃ , Bi ₂ T
e ₃ , SnSb, FeTe, Fe ₂ Te ₃ , FeTe ₂ , Z
nSb, Zn ₃ Sb ₂ , VTe ₂ , V ₅ Te ₈ , AgIn ₂ ,
Even if the material having at least one of BiSe, InSb, In ₂ Te, and In ₂ Te ₅ as a main component or a material having a composition close to that of BiSe, InSb, or similar is substituted, similar characteristics can be obtained.

The remaining component is preferably a metal, compound or alloy having a melting point of 650 ° C or lower.

Also, in the super-resolution reading, if the film thickness of each layer is changed, it is possible to mask only the area other than the shaded area in the light spot, contrary to FIG.

When the melting point of the residual component is 250 ° C. or lower and the melting point of the high melting point component is 450 ° C. or higher, characteristics close to this can be obtained.

When a recording mark having a length of about 25% of the diameter of the light spot 31 is formed, the change amount Δk ′ of the extinction coefficient k of the mask layers 13 and 13 ′ before and after the laser light irradiation is When it changed, the C / N of the reproduced signal after reading 10 ⁵ times changed as follows.

C / N of reproduced signal after reading 10 ⁵ times Δk ′ = 5% 37 dB Δk ′ = 10% 42 dB Δk ′ = 20% 46 dB Δk ′ = 30% 48 dB From this result, 20% ≦ It was found that the range of Δk ′ is preferable.

Melting point (m.p.) of the remaining component after precipitation of the high melting point component.
p. ) Has changed, the C / N of the reproduced signal after reading 10 ⁵ times changed as follows.

C / N of reproduced signal after 10 ⁵ times reading m. p. = 100 ° C. 49 dB m.p. p. = 250 ° C. 48 dB m.p. p. = 400 ° C. 47 dB m.p. p. = 650 ° C. 46 dB m.p. p. = 700 ° C. 40 dB m.p. p. = 750 ° C 33 dB From this result, the melting point of the remaining component after the high melting point component is precipitated is 6
It was found that the temperature is preferably 50 ° C or lower, more preferably 250 ° C or lower.

[Embodiment 22] In FIG. 9, the phase change type information recording medium of Embodiment 1 is provided with the same mask layer as that of Embodiment 4, whereby the "super-resolution effect" can be utilized at the time of reproducing information. This is an example of the information recording medium thus configured.

This disc-shaped medium has the same structure as the information recording medium of Example 1 except that the structure of the recording film is different.
That is, the same polycarbonate substrate 1 as in Example 1,
Protective layers 2 and 2'of a (ZnS) ₈₀ (SiO ₂ ) ₂₀ film are respectively formed on the protective film 1 ', and recording films 3, 3'and (ZnS) are formed on the protective layers 2 and 2'in that order. ) ₈₀ (SiO ₂ )
Intermediate layers 4, 4'made of ₂₀ films and reflective layers 5, 5'made of Al ₉₇ Ti ₃ films are respectively formed. The reflective layers 5 and 5 ′ are attached to each other with an adhesive layer 6.

The recording film 3'is composed of a mask layer, a dielectric layer and a recording layer which are sequentially arranged from the substrate 1'side. The recording film 3 also has the same structure as the recording film 3 '.

The mask layer is the same as in Example 21 (((Ag ₂
Te) ₃₀ (Se ₈₀ -Te ₂₀ ) _70, that is, Ag ₂₀ Te ₂₄ S
It has the composition of e ₅₆ and has the same mask function as in Example 21. The dielectric layer is formed of a (ZnS) ₈₀ (SiO ₂ ) ₂₀ film. As the recording layer, in addition to the same recording layers 3 and 3'of Example 1, any phase change type recording layer can be used.

A recording mark of 0.4 μm in length is 0.8 μm in length.
When formed in a cycle, the C / N of the reproduced signal obtained is 46.
The erasure ratio was 25 dB or more.

This mask layer is the same in the conventional information recording medium other than the information recording thin film of the present invention, which records by a phase change and in the information recording medium based on the recording principle other than the phase change such as a magneto-optical disk. Have an effect.

Regarding points not mentioned in this embodiment,
This is the same as in the first embodiment.

[Embodiment 23] Although not shown, the disk-shaped information recording medium of this embodiment has almost the same structure as that shown in FIG. The only difference is that instead of the layers 1 and 1 ′, a layer containing a high melting point component such as the recording films 3 and 3 ′ is used as a reflective layer.

The high melting point component in the reflective layer is the same as in Example 1.

Regarding the residual component after the high melting point component in the reflective layer is deposited, a metal, compound or alloy having a melting point of 650 ° C. or lower is preferable, and the real part n of the complex refractive index is n.
Alternatively, it is preferable that the imaginary part (extinction coefficient) k is changed by 20% or more by the irradiation of the laser beam, and the reflectance R is 60% or more when the real part n and the imaginary part k are high.

As a reflective layer, a film having a thickness of 80 nm (LaB
i) When ₃₀ Bi ₇₀ layer is used, the super resolution effect at the time of reading is obtained, and the recording mark of 0.4 μm in length is 0.8 μm.
When written in cycles, the C / N of the obtained reproduced signal is 46d.
B or more and the erasing ratio was 25 dB or more. Note that (La
In the Bi) ₃₀ Bi ₇₀ layer, the high melting point component is LaBi,
The phase change component is Bi.

The principle of obtaining the super-resolution effect is as follows. As shown in FIG. 8, in the high temperature region 35 in the light spot 31, at least one of the real number part n and the imaginary number part k of the complex refractive index is lowered by melting at least the phase change component Bi in the reflective layer, Area 3 that works as the mask in FIG. 8
The reflected light at 3 becomes weaker. Therefore, the reflected light from the range 33 cannot provide the recording film with sufficient contrast for reading.

On the other hand, in the low temperature region of the crystallized solid state, at least one of the real number part n and the imaginary number part k of the complex refractive index is larger than that in the high temperature region, so that a sufficient contrast for reading can be provided.

As a result, the detection range 34 becomes a crescent shape as shown in FIG. 8, and it becomes possible to reliably read out the recording marks 32 recorded at high density in a cycle equal to or smaller than the diameter of the light spot 31.

The size of the detection range 34 can be changed by changing the film thickness of each layer.

(Another Example of Remaining Component) Some or all of Bi, which is the remaining component of the high-melting point component LaBi, is replaced with Sn, Pb, S.
b, Te, Zn, Cd, Se, In, Ga, S, Tl,
Mg, Tl ₂ Se, TlSe, Tl ₂ Se ₃ , Tl ₃ T
e ₂ , TlTe, InBi, In ₂ Bi, TeBi, Tl
-Se, Tl-Te, Pb-Sn, Bi-Sn, Se-
Te, S-Se, Bi-Ga, Sn-Zn, Ga-S
_{n, Ga-In, In 3} SeTe 2, AgInTe 2, G
eSb ₄ Te ₇ , Ge ₂ Sb ₂ Te ₅ , GeSb ₂ Te ₄ , G
eBi ₄ Te ₇ , GeBi ₂ Te ₄ , Ge ₃ Bi ₂ Te ₆ , S
n ₂ Sb ₆ Se ₁₁ , Sn ₂ Sb ₂ Se ₅ , SnSb ₂ Te ₄ ,
Pb ₂ Sb ₆ Te ₁₁ , CuAsSe ₂ , Cu ₃ AsSe ₃ ,
CuSbS ₂ , CuSbSe ₂ , InSe, Sb ₂ Se ₃ ,
Sb ₂ Te ₃ , Bi ₂ Te ₃ , SnSb, FeTe, Fe ₂
Te ₃ , FeTe ₂ , ZnSb, Zn ₃ Sb ₂ , VTe ₂ ,
V ₅ Te ₈ , AgIn ₂ , BiSe, InSb, In ₂ T
Even if the material having at least one of e, In ₂ Te ₅ , etc. as a main component is replaced, similar characteristics can be obtained.

When the melting point of the residual component is 350 ° C. or lower, and the melting point of the high melting point compound is 450 ° C. or higher, characteristics close to those in the above case can be obtained.

(Others) The reflective layer of this embodiment can be applied to other recording mediums such as an optical recording medium which does not use the recording thin film of the present invention for recording by conventional phase change and a magneto-optical recording medium. Applicable.

Items not mentioned here are the same as in the first embodiment.

[0449]

As described above, according to the information recording thin film and the information recording medium of the present invention, it is possible to rewrite a number of times more than before while maintaining good recording / reproducing characteristics.

According to the method for manufacturing the information recording thin film of the present invention, the information recording thin film and the information recording medium of the present invention can be easily obtained.

As described above, according to the present invention, a super-resolution reading thin film, an information recording medium and a super-resolution reading device capable of performing super-resolution reading a large number of times and having excellent super-resolution reading characteristics. Can be obtained.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view of a recording thin film of an embodiment of an information recording medium of the present invention, (a) shows a granular high melting point component deposited, and (b) shows a columnar high melting point component deposited. ,
(C) shows a porous high melting point component deposited.

FIG. 2 is a partial cross-sectional view of an embodiment of the information recording medium of the present invention, (a) is a cross-sectional view taken along the line D-D of (b), (b).
FIG. 3 is a partial sectional view of the information recording medium.

FIG. 3 is an overall sectional view of an embodiment of the information recording medium of the present invention.

4A and 4B are partial cross-sectional views illustrating a method for measuring the dimension of a high melting point component deposited in a recording thin film, where FIG. 4A is a granular high melting point component, and FIGS. 4B and 4C are columnar high melting point components. Is shown.

5 shows an embodiment of the information recording medium of the present invention, FIG.
It is a fragmentary sectional view similar to (a).

FIG. 6 is a triangular phase diagram of an example of a recording layer of the information recording thin film of the present invention.

FIG. 7 is an overall sectional view of another embodiment of the information recording medium of the present invention.

FIG. 8 is a diagram for explaining the principle of the super-resolution effect.

FIG. 9 is an overall sectional view of still another embodiment of the information recording medium of the present invention.

FIG. 10 is a triangular phase diagram of Example 4 of the recording layer of the information recording thin film of the present invention.

FIG. 11 is a triangular phase diagram of Example 5 of the recording layer of the information recording thin film of the present invention.

FIG. 12 is a diagram showing an example of a sectional structure of a super-resolution read disk according to the present invention.

FIG. 13 is a diagram showing the relationship between the film thickness of a super-resolution readout film and the reflectance.

FIG. 14 is a block diagram of a super-resolution reading device.

[Explanation of symbols]

1, 1 '... Substrate, 2, 2' ... Protective layer, 3, 3 '... Recording film, 3a ... Phase change component, 3b ... High melting point component, 4, 4' ...
Intermediate layer, 5, 5 '... Reflective layer, 6 ... Adhesive layer, 11, 1
1 '... Substrate, 12, 12' ... Protective layer, 13, 13 '... Recording film, 14, 14' ... Intermediate layer, 15, 15 '... Reflective layer,
16 ... Adhesive layer, 32a, 32b ... Recording mark, 33 ...
Area acting as a mask, 34 ... Detection area, 35 ... High temperature area.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location G11B 7/26 531 7215-5D

Claims (75)

[Claims] 1. An information recording thin film, which is formed directly on a substrate or through a protective layer and records / reproduces information by an atomic arrangement change caused by irradiation with an energy beam, wherein the information recording thin film is formed. The average composition in the thickness direction is represented by the general formula Sb _x Te _y A _p B _q C _r (1), wherein A is at least one element selected from the first group consisting of Ge and In, and B is Lanthanoid element and Ag, Ba, Co, Cr, Ni, Pt, Si, Sr, A
u, Cd, Cu, Li, Mo, Mn, Zn, Al, F
e, Pb, Na, Cs, Ga, Pd, Bi, Sn, Ti
And at least one element selected from the second group consisting of V, C represents Sb, Te and at least one element other than the elements represented by A and B, and x, y, p, q and r The units of are all atomic percentages, and 2 ≦ x ≦ 41, 25 ≦ y ≦ 75,
An information recording thin film having a range of 0.1 ≦ p ≦ 60, 3 ≦ q ≦ 40, and 0.1 ≦ r ≦ 30. 2. An information recording thin film, which is formed on a substrate directly or through a protective layer and records / reproduces information by an atomic arrangement change caused by irradiation of an energy beam, wherein the information recording thin film is formed. The average composition in the thickness direction is represented by the general formula Sb _x Te _y A _p B _q (2), wherein A is at least one element selected from the first group consisting of Ge and In, and B is a lanthanoid element. And Ag, Ba, Co, Cr, Ni, Pt, Si, Sr, A
u, Cd, Cu, Li, Mo, Mn, Zn, Al, F
e, Pb, Na, Cs, Ga, Pd, Bi, Sn, Ti
And at least one element selected from the second group consisting of V, wherein the units of x, y, p and q are all atomic percentages, and 2≤x≤41, 25≤y≤75,0. 1
An information recording thin film having a range of ≦ p ≦ 60 and 3 ≦ q ≦ 40. 3. An information recording thin film, which is formed on a substrate directly or through a protective layer and records / reproduces information by an atomic arrangement change caused by irradiation of an energy beam, wherein the information recording thin film is formed. The average composition in the thickness direction is represented by the general formula Sb _x Te _y B _q C _r (3), where B is a lanthanoid element and Ag, Ba, Co, C
r, Ni, Pt, Si, Sr, Au, Cd, Cu, L
i, Mo, Mn, Zn, Al, Fe, Pb, Na, C
at least one element selected from the group consisting of s, Ga, Pd, Bi, Sn, Ti and V, wherein C is Sb, T
e and at least one element other than the element represented by B, wherein the units of x, y, p and q are all atomic percentages, and 2 ≦ x ≦ 41, 25 ≦ y ≦ 75, 3 ≦ q, respectively.
An information recording thin film having a range of ≦ 40 and 0.1 ≦ r ≦ 30. 4. An information recording thin film, which is formed directly on a substrate or through a protective layer and records / reproduces information by an atomic arrangement change caused by irradiation of an energy beam, wherein the information recording thin film is formed. The average composition in the thickness direction is represented by the general formula: Sb _x Te _y B _q (4), where B is a lanthanoid element and Ag, Ba, Co, C
r, Ni, Pt, Si, Sr, Au, Cd, Cu, L
i, Mo, Mn, Zn, Al, Fe, Pb, Na, C
Represents at least one element selected from the group consisting of s, Ga, Pd, Bi, Sn, Ti and V, wherein the units of x, y and q are all atomic percentages and 2 ≦ x ≦ 41,25, respectively. ≦ y ≦ 75, 3 ≦ q ≦
An information recording thin film having a thickness in the range of 40. 5. An information recording thin film, which is formed on a substrate directly or through a protective layer and records / reproduces information by an atomic arrangement change caused by irradiation with an energy beam, wherein the information recording thin film is formed. The average composition in the thickness direction is represented by the general formula (Ge _a Sb _b Te _c ) _1-d X _d (5), where X is Cr and Ag, Ba, Co, Ni, Pt, S.
i, Sr, Au, Cd, Cu, Li, Mo, Mn, Z
n, Al, Fe, Pb, Na, Cs, Ga, Pd, B
i, Sn, Ti, V, In, W, Zn, and at least one element of lanthanoid elements, wherein a, b, c, and d are 0.02 ≦ a ≦ 0.1, respectively.
9, 0.04 ≦ b ≦ 0.4, 0.5 ≦ c ≦ 0.75
An information recording thin film having a range of 0.03 ≦ d ≦ 0.3. 6. An information recording thin film, which is formed directly on a substrate or through a protective layer and records / reproduces information by an atomic arrangement change caused by irradiation of an energy beam, wherein the information recording thin film is formed. The average composition in the thickness direction is represented by the general formula (Ge _a Sb _b Te _c ) _1-d X _d (5), where X is Cr and Ag, Ba, Co, Ni, Pt, S.
i, Sr, Au, Cd, Cu, Li, Mo, Mn, Z
n, Al, Fe, Pb, Na, Cs, Ga, Pd, B
i, Sn, Ti, V, In, W, Zn and at least one element of lanthanoid elements,
c and d are respectively 0.25 ≦ a ≦ 0.65, 0 ≦
b ≦ 0.2, 0.35 ≦ c ≦ 0.75, 0.03 ≦ d ≦
An information recording thin film, which is in the range of 0.3. 7. The method according to claim 1, wherein at least one of B and X has a concentration gradient in the film thickness direction.
7. The information recording thin film as described in any one of 1 to 6. 8. A deposit containing a high melting point component having a relatively higher melting point than the remaining components of the thin film, and the deposit contains an element represented by at least one of B and X. The information recording thin film according to any one of 1 to 6. 9. A precipitate comprising a high melting point component having a melting point relatively higher than that of the remaining component of the thin film, wherein at least a part of the high melting point component is averaged in a discontinuous film form on the light incident side of the thin film. 7. The information recording thin film according to claim 1, wherein the thin film exists in a film thickness range of 1 to 10 nm. 10. A deposit containing a high melting point component having a melting point relatively higher than that of the remaining components of the thin film, wherein the sum of the numbers of constituent elements of the high melting point component is the total number of atoms of the constituent elements of the thin film. It is in the range of 10 to 50% with respect to the sum of numbers.
7. The information recording thin film as described in any one of 2, 5 and 6. 11. A deposit containing a high melting point component having a melting point relatively higher than that of the remaining components of the thin film, wherein the content of the high melting point component varies in the film thickness direction. 7. The information recording thin film as described in any one of 2, 5 and 6. 12. A low melting point component L of elemental simple substance or compound composition, which contains a precipitate composed of a high melting point component having a melting point relatively higher than that of the remaining components of the thin film,
When expressed by the formula of L _j H _k (6) with the element alone or the high melting point component H of the compound composition, 20 ≦ k / (j + k) ≦ 40
The content of each element constituting the information recording thin film in the film is within a range of ± 10 atomic% determined by the above formula, with the composition of (7) as a reference composition. The information recording thin film as described in any one of 1, 2, 5 and 6. 13. A deposit comprising a high melting point component having a melting point relatively higher than that of the remaining components of the thin film, wherein the melting point of the high melting point component is 780 ° C. or higher. The information recording thin film as described in any one of 1. 14. A precipitate comprising a high melting point component having a melting point relatively higher than that of the remaining component of the thin film, wherein the difference between the melting point of the high melting point component and the melting point of the remaining component of the thin film is 150 ° C. or more. The information recording thin film according to any one of claims 1, 2, 5 and 6. 15. A precipitate containing a high melting point component having a melting point relatively higher than that of the remaining component of the thin film is contained, and the precipitate of the high melting point component is distributed in a granular or columnar shape inside the thin film. The information recording thin film according to claim 1, 2, 5, or 6. 16. A thin-film containing a precipitate of a high-melting point component having a melting point relatively higher than that of the remaining component of the thin film, and the maximum outer dimension of the precipitate of the high-melting point component in the film surface direction of the thin film is 5 nm.
The information recording thin film according to any one of claims 1, 2, 5 and 6, having a thickness of 50 nm or less. 17. A precipitate comprising a high melting point component having a melting point relatively higher than that of the remaining component of the thin film, wherein the high melting point component is columnar in the thickness direction from both interfaces of the thin film. 7. The information recording according to claim 1, wherein the length of the precipitate in the film thickness direction is 5 nm or more and is (1/2) or less of the film thickness of the thin film. Thin film. 18. A precipitate comprising a high melting point component having a melting point relatively higher than that of the remaining component of the thin film, wherein the high melting point component precipitates from one interface of the thin film in a columnar direction in the film thickness direction. And the length of the precipitate in the film thickness direction is 10
The film thickness is not less than nm and not more than the film thickness of the thin film.
5. The information recording thin film as described in any one of 5 and 6. 19. A thin film containing a precipitate of a high melting point component having a melting point relatively higher than that of the remaining component of the thin film, wherein the length of the precipitate of the high melting point component in the film thickness direction is 10 nm or more. The information recording thin film according to any one of claims 1, 2, 5 and 6, which has a thickness of not more than a film thickness. 20. A deposit containing a high-melting point component having a melting point relatively higher than that of the remaining components of the thin film, which are adjacent to each other.
The straight line connecting the centers of the two high melting point component precipitates has a length of 20 nm or more and 90 nm or less passing through a region between the precipitates in the film surface direction of the thin film.
And the information recording thin film as described in any one of 6 and 6. 21. A porous deposit containing a high melting point component having a relatively higher melting point than the residual component of the thin film is contained, and the residual component is distributed in the pores of the porous deposit. Item 7. An information recording thin film according to any one of items 1, 2, 5 and 6. 22. A precipitate comprising a high melting point component having a melting point relatively higher than that of the remaining component of the thin film, wherein the maximum number of pores of the porous precipitate of the high melting point component in the film surface direction of the thin film. The pore size is 80 nm or less, and the maximum wall thickness in the film surface direction of the thin film in the region between two adjacent pores is 20 nm.
The information recording thin film according to any one of claims 1, 2, 5 and 6 below. 23. A deposit comprising a high melting point component having a melting point relatively higher than that of the remaining component of the thin film, and the melting point of the remaining component of the thin film is 650 ° C. or lower.
And the information recording thin film as described in any one of 6 and 6. 24. A precipitate comprising a high melting point component having a melting point relatively higher than that of the residual component of the thin film, and the melting point of the residual component of the thin film is 250 ° C. or lower.
And the information recording thin film as described in any one of 6 and 6. 25. A precipitate comprising a high melting point component having a relatively higher melting point than the remaining component of the thin film, wherein at least one of the real part and the imaginary part of the complex refractive index of the thin film is
7. The information recording thin film according to claim 1, which changes by 20% or more with respect to that before irradiation by irradiation with light. 26. A thin film for information recording, which is formed on a substrate directly or through a protective layer and records / reproduces information by an atomic arrangement change caused by irradiation of an energy beam, relative to a remaining component of the thin film. A thin film for information recording, characterized in that it contains a precipitate consisting of a high melting point component having a high melting point, and the precipitate is distributed in a region consisting of the remaining component of the thin film. 27. The information recording thin film according to claim 26, wherein the maximum outer dimension of the precipitate of the high melting point component in the film surface direction is 5 nm or more and 50 nm or less. 28. The precipitate of the high melting point component extends in a columnar shape from both interfaces of the thin film in the film thickness direction thereof, and the length of the precipitate in the film thickness direction is 5 nm or more. 27. The information recording thin film according to claim 26, which has a thickness of (1/2) or less. 29. The precipitate of the high melting point component extends in a column shape from one interface of the thin film in the film thickness direction thereof, and the length of the precipitate in the film thickness direction is 10 nm or more. The information recording thin film according to claim 26, which has a thickness of not more than the film thickness. 30. The information recording thin film according to claim 26, wherein the length of the high melting point component precipitate in the film thickness direction is 10 nm or more and less than or equal to the film thickness of the thin film. 31. A straight line connecting the centers of two adjacent precipitates of the high melting point component has a length of 20 nm or more and 90 nm or less passing through a region between the precipitates in the film surface direction of the thin film. The information recording thin film according to claim 26. 32. A thin film for information recording, which is formed on a substrate directly or through a protective layer and records / reproduces information by an atomic arrangement change caused by irradiation of an energy beam, relative to a remaining component of the thin film. A thin film for information recording, characterized in that it contains a porous precipitate composed of a high melting point component having a high melting point, and the remaining components of the thin film are distributed in the pores of the porous precipitate. 33. A film of the thin film in a region between two adjacent holes, wherein the maximum internal dimension of the holes of the porous precipitate of the high melting point component in the film surface direction of the thin film is 80 nm or less. The information recording thin film according to claim 32, wherein the maximum wall thickness in the surface direction is 20 nm or less. 34. The information recording thin film according to claim 26, wherein the melting point of the remaining components of the thin film is 650 ° C. or lower. 35. The information recording thin film according to claim 26, wherein the melting point of the remaining components of the thin film is 250 ° C. or lower. 36. The information recording thin film according to claim 26, wherein at least one of a real number part and an imaginary number part of a complex refractive index of the thin film changes by 20% or more with respect to that before irradiation by light irradiation. 37. The information recording thin film according to claim 26, wherein the sum of the numbers of atoms of the constituent elements of the high melting point component is in the range of 10 to 50% with respect to the sum of the number of all atoms of the thin film. . 38. When the average composition is represented by the formula L _j H _k (6) by the low melting point component L of the element simple substance or the compound composition and the high melting point component H of the element simple substance or the compound composition, 20 ≦ k / ( j + k) ≦ 40 (7)
The content of each element constituting the above information recording thin film in the film is a value determined by the above formula ± 1.
33. The information recording thin film according to claim 26, wherein the thin film is in the range of 0 atomic%. 39. The information recording thin film according to claim 26, wherein the high melting point component has a melting point of 780 ° C. or higher. 40. The information recording thin film according to claim 26, wherein a difference between the melting point of the high melting point component and the melting point of the remaining component of the thin film is 150 ° C. or more. 41. The information recording thin film according to claim 1, wherein the element represented by at least one of B and X is Cr. 42. The information recording thin film according to claim 1, wherein the element represented by at least one of B and X is Mo and Si, Pt, Co, Mn, W. 43. A method of manufacturing an information recording thin film, which is formed directly on a substrate or through a protective layer and records / reproduces information by an atomic arrangement change caused by irradiation with an energy beam, comprising: For recording information, comprising a step of forming a thin film directly on or through a protective layer, and a step of irradiating the thin film with an energy beam to generate or grow a high melting point component in the thin film. Thin film manufacturing method. 44. A method of manufacturing an information recording thin film, which is formed on a substrate directly or through a protective layer and records / reproduces information by an atomic arrangement change caused by irradiation with an energy beam, comprising: Directly or through a protective layer to deposit a material having a high melting point component or a material having a composition close to that of the high melting point component to form an island-shaped seed crystal, and the high melting point on the seed crystal. Depositing a material containing a component and the residual component, selectively growing the high melting point component on the seed crystal, and growing the residual component so as to fill the space between the seed crystals. A method of manufacturing a thin film for information recording, comprising: 45. A method of manufacturing an information recording thin film, which is formed directly on a substrate or through a protective layer and records or reproduces information by an atomic arrangement change caused by irradiation with an energy beam, the method comprising: And a step of changing the content of the high melting point component in the film thickness direction when forming a film composed of a phase change component and a high melting point component directly or through a protective layer. Method. 46. An information recording medium comprising the information recording thin film according to any one of claims 1 to 6, 26 and 32 as a recording layer. 47. An information recording medium comprising the information recording thin film according to any one of claims 1 to 6, 26 and 32 as a mask layer for super-resolution reading. 48. An information recording medium comprising the information recording thin film according to any one of claims 1 to 6, 26 and 32 as a reflective layer for super-resolution reading. 49. An information recording medium provided with the information recording thin film according to claim 1, wherein the melting point of the residual component after the precipitation of the high melting point component is 650 ° C. or lower. . 50. An information recording medium provided with the information recording thin film according to claim 1, wherein the reflection layer has a reflectance of 60% or more. 51. An information recording thin film according to any one of claims 1 to 6, 26 and 32 is provided as a recording layer or a mask layer for super-resolution reading, and a layer containing Si on the reflective layer side and recording. An information recording medium provided with an intermediate layer having a two-layer structure of a layer containing ZnS as a main component on the film side. 52. An information recording thin film, which is formed on a substrate directly or through a protective layer and records or reproduces information by an atomic arrangement change caused by irradiation with an energy beam, is used for a recording layer or super-resolution readout. Of the present invention, and an information recording medium provided with a reflective layer having at least one of Si-Sn, Si-Ge, and Si-In compounds, or a composition close to this. 53. An information recording thin film, which is formed directly on a substrate or through a protective layer and records or reproduces information by an atomic arrangement change caused by irradiation of an energy beam, is used for a recording layer or super-resolution readout. The information recording medium, which is provided as a mask layer and has a reflective layer thickness of 150 nm or more and 300 nm or less. 54. An information recording thin film, which is formed directly on a substrate or through a protective layer and records or reproduces information by an atomic arrangement change caused by irradiation of an energy beam, is used for a recording layer or super-resolution reading. As a mask layer, and a SiO ₂ layer on the light incident side and a ZnS—S layer on the recording film side.
An information recording medium having a protective layer having a two-layer structure of an iO ₂ layer. 55. A super-resolution readout thin film formed on a substrate directly or through a protective layer to produce a super-resolution effect upon irradiation with a readout beam, at least a phase change component and the phase change component. A thin film for super-resolution reading, comprising a high melting point component having a higher melting point, and the high melting point component being precipitated. 56. The thin film for super-resolution readout according to claim 55, wherein the high melting point component is deposited as a columnar or massive precipitate. 57. The thin film for super-resolution readout according to claim 55, wherein the high melting point component is deposited as a porous deposit. 58. A thin film for super-resolution reading, which is formed on a substrate directly or through a protective layer to produce a super-resolution effect upon irradiation with a reading beam and has an average composition of the general formula D _e E _f. Is represented by F _g , and D is Sn, Pb, Bi, Zn, Ga, I
at least one element selected from n, E is As,
B, C, N, O, S, Se, Si, Te, Ag, Al,
Au, Ba, Be, Ca, Cd, Co, Cr, Cs, C
u, Fe, Ge, Hf, Hg, Ir, K, Li, Mg,
Mn, Mo, Na, Nb, Ni, Os, Pd, Pt, R
b, Re, Rh, Ru, Sb, Sc, Sr, Ta, T
at least one element selected from the group consisting of i, V, W, Y, and Zr, F represents at least one element other than those represented by D and E, and units of e, f, and g Are atomic percentages, and 30 ≦ e ≦
56. The thin film for super-resolution readout according to claim 55, which is in a range of 95, 5≤f≤50, and 0≤g≤20. 59. When the average composition is expressed by the formula L _j H _k (6) by the low melting point component L of the element simple substance or the compound composition and the high melting point component H of the element simple substance or the compound composition, 20 ≦ k / ( j + k) ≦ 40 (7)
The thin film for super-resolution readout according to claim 55, characterized in that the content of each element in the film is within a range of a value determined by the above formula ± 10 at. 60. The thin film for super-resolution readout according to claim 55, wherein both the low melting point component and the high melting point component contain 50 atomic% or more of a metal or metalloid element. 61. An information recording medium characterized in that the thin film for super-resolution reading according to claim 55 is provided on a transparent substrate on which information is recorded by unevenness, and a reflective layer is provided thereon. 62. An information recording medium, characterized in that a protective layer is provided between the transparent substrate on which information is recorded by unevenness and the thin film for super-resolution reading according to claim 55. 63. An information recording medium, wherein an intermediate layer is provided between the thin film for super-resolution reading and the reflective layer according to claim 55. 64. An information recording characterized in that the thin film for super-resolution reading according to claim 55 is provided on a transparent substrate, an information recording film is provided thereon, and a reflective layer is further provided thereon. Medium. 65. An information recording medium, wherein a protective layer is provided between the transparent substrate and the super-resolution reading thin film according to claim 55. 66. An intermediate layer is provided between at least one of the thin film for super-resolution reading and the information recording film according to claim 55 and between the information recording film and the reflective layer. Information recording medium. 67. A super-resolution comprising an information recording medium comprising the super-resolution reading thin film according to claim 55, and an optical head for irradiating the information recording medium with a laser beam to detect reflected light. In the reading device, there is provided means for detecting a disturbance in the intensity distribution of the reflected light at the time of super-resolution reading, and means for adjusting the laser power according to the magnitude of the disturbance, for the super-resolution reading. apparatus. 68. A super-resolution reading device comprising: an information recording medium comprising the thin film for super-resolution reading according to claim 55; and an optical head for irradiating the information recording medium with a laser beam to detect reflected light. In the apparatus, the laser light is pulsed light, and the relationship among the period T of the laser pulse, the linear velocity v, the spot diameter (λ / NA), and the pulse width x is 0.4λ / NA ≦ vT ≦ 1.5λ / NA. (9) And 0.3 <= x / T <= 0.5 (10) The super-resolution reading apparatus characterized by the above-mentioned. 69. A super-resolution readout comprising an information recording medium comprising the thin film for super-resolution readout according to claim 55 and an optical head for irradiating the information recording medium with a laser beam to detect reflected light. A device for super-resolution reading, characterized in that it has means for setting the output of the laser light so that the entire film is not melted even in the region where the maximum temperature of the thin film for super-resolution reading is reached. 70. An information recording thin film, which is formed directly on a substrate or through a protective layer and records / reproduces information by an atomic arrangement change caused by irradiation of an energy beam, for information recording having the thin film. By repeatedly irradiating a laser beam in a device for recording / reproducing information using a medium or a device for initial crystallization of a medium, a high melting point component having a relatively higher melting point than the remaining components of the thin film is deposited, and the deposit is the thin film. A thin film for information recording, characterized in that it is distributed in a region consisting of the residual component of. 71. Information using an information recording medium having an information recording thin film, which is formed directly on a substrate or through a protective layer and records / reproduces information by an atomic arrangement change caused by irradiation with an energy beam. By repeatedly irradiating the laser beam in the recording / reproducing method or the medium initial crystallization method, a high-melting point component having a relatively higher melting point than the remaining component of the thin film is deposited, and the precipitate is separated from the remaining component of the thin film. A recording / reproducing method of information, which is characterized in that the information is distributed in a predetermined area. 72. In the thin film, a laser beam is repeatedly irradiated in an information recording / reproducing apparatus or a medium initial crystallization apparatus using an information recording medium having the thin film, whereby the residual component of the thin film is relatively exposed. A high-melting point component having a high melting point is deposited, the deposit is distributed in a region consisting of the remaining components of the thin film, and the deposit contains an element represented by at least one of B and X. Item 7. An information recording thin film according to any one of Items 1 to 6. 73. A method of manufacturing an information recording medium, which is formed directly on a substrate or through a protective layer and records / reproduces information by an atomic arrangement change caused by irradiation with an energy beam, the method comprising: A step of forming a protective layer, a recording film or a super-resolution reading film, an intermediate layer, and a reflective layer, and a step of adhering another substrate or another substrate on which each of the layers is formed in the same manner to the medium. And a step of irradiating an energy beam to generate or grow a high melting point component in the thin film, the method for manufacturing an information recording medium. 74. A method of manufacturing an information recording medium, which is formed on a substrate directly or via a protective layer and records / reproduces information by a change in atomic arrangement caused by irradiation with an energy beam, the method comprising: A step of forming a protective layer on and a step of forming an island-shaped seed crystal by depositing a material having a high melting point component or a material having a composition close to that of the high melting point component,
A material containing the high melting point component and the residual component is deposited on the seed crystal, the high melting point component is selectively grown on the seed crystal, and the gap between the seed crystals is filled with the material. Information recording comprising a step of growing a residual component, a step of forming an intermediate layer and a reflective layer, and a step of adhering another substrate or another substrate on which each of the layers has been formed in the same manner to this. Of manufacturing a recording medium. 75. A method for manufacturing an information recording medium, which is formed directly on a substrate or through a protective layer and records or reproduces information by a change in atomic arrangement caused by irradiation with an energy beam, the method comprising: A step of forming a protective layer on the substrate, a step of changing the content of the high melting point component in the film thickness direction while forming a film composed of a phase change component and a high melting point component, and a step of forming an intermediate layer and a reflective layer. A method for manufacturing an information recording medium, further comprising the step of adhering another substrate or another substrate on which each layer is formed in the same manner thereto.