JP2009245504A - Master disk for manufacturing optical information recording medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a master disk for manufacturing an optical information recording medium, which improves thermal interference occurring when a convex-type structure is formed. <P>SOLUTION: The master disk for manufacturing the optical information recording medium comprises a recording layer including a laminate of a recording auxiliary layer provided in contact with the substrate and a thermosensitive layer. The thermosensitive layer includes a base material which changes a state due to exposure, and the recording auxiliary layer is formed of material absorbing light of a wavelength to be used for exposure and having heat conductivity higher than that of the substrate. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an optical information recording medium such as an optical disk, and more particularly to a master for manufacturing an optical information recording medium for replication of the optical information recording medium.

  High-density optical discs with increased data recording density have been studied. In a high-density optical disc, in order to realize a large capacity, the beam spot diameter of a laser beam used for recording / reproducing data must be very small. For example, in order to reduce the beam spot diameter, the numerical aperture (NA) of the objective lens for condensing the laser beam is increased to 0.7 or more, for example, about 0.85, and the wavelength λ of the laser beam is set to be small. It is shortened to 450 nm or less, for example, about 400 nm.

  Conventional optical discs such as CDs, DVDs, and BDs are a read-only ROM (Read Only Memory) type optical disc that cannot be additionally written or rewritten, and a write-once optical disc that can additionally write data but cannot rewrite data. It can be roughly divided into rewritable optical discs of the type that can rewrite data.

  In ROM type optical discs, data is pre-recorded by pre-pits formed on the substrate in the manufacturing stage, and in write-once and rewritable optical discs, pre-pits and tracks are formed in advance, on which organic dyes, phase change materials, etc. A recording material layer is formed, and data is recorded using a change in optical characteristics based on a chemical physical change in the recording material layer. In these optical discs other than ROM type, generally, signals such as wobbling signals used for optical disc rotation control and address information necessary for position search at the time of data recording are pre- It is recorded on a track (groove or land) which is a concave or convex portion. Both optical disks are manufactured by replication, and a concave / convex pattern such as a track is recorded on a master, a disk stamper is formed from the master, and a synthetic resin or the like is heated and pressed or injection molded using the disk stamper. A translucent substrate having a recording surface transferred from the master is formed and obtained.

  For example, in LBR (Laser beam recording), the recording of a predetermined pattern is performed by a cutting device. While rotating the blank master, the recording surface is irradiated with a laser beam, and the laser beam is sent in the radial direction. The laser spot draws a spiral track locus at a predetermined pitch, and a pit or groove is recorded on the master disk by turning on / off the laser beam in accordance with the rotation speed and information content of the recording master disk on the locus.

  In recent years, research and development of a recording medium with a higher density exceeding the recording density of the BD has been promoted, and it is desired to make the pitch of the track extremely fine.

  In order to realize high resolution patterning of pre-pits and tracks, as a means for producing a high-density optical disc master, a combination of organic resist and LBR, a combination of inorganic resist and PTM (Phase Transition Mastering), an inorganic resist and EBR (Electronic beam) The production process by the combination of recording) is common.

  Currently, the mainstream of BD-ROM (single-sided capacity 25GB / diameter 120cm) master disk is the one that uses LBR and PTM. A technique using PTM and EBR that can be easily resolved is employed. In PTM, there are the following proposals.

  As a method for producing an authoring optical recording medium having a concavo-convex pattern such as prepits and tracks, a step of sequentially laminating a first dielectric layer, a light absorbing layer, and a second dielectric layer on a support substrate, and laser irradiation There has been proposed a method including at least a step of recording information and a step of removing a non-recorded portion of the second dielectric layer and processing it into a convex shape by solution etching (see Patent Document 1).

  As an optical recording medium having a structure capable of reducing the track pitch and achieving a high recording density, at least a heating material that generates heat by light irradiation, a structure, and a recording material that generates heat and records information by light irradiation are laminated. A mixture material of a silicon compound (material A) and at least one material (material B) selected from the group of sulfide materials, selenide materials, fluoride materials, nitride materials, metal materials, and semiconductor materials, An optical recording medium has been proposed in which the structure is provided in a state where the structure is completely separated from the adjacent structure in the medium plane (see Patent Document 2).

  As a method for producing an optical recording medium that forms a fine structure at a low cost with a simple process, using a medium having a laminated structure of a light absorption layer and a thermal reaction layer, at least irradiating the medium with light, In the structure forming method of forming a fine structure by a process of etching the medium, the thermal reaction layer: at least one material (B) of Si oxide (A) and sulfide, selenide, or fluorine compound is used. Mixing has been proposed (see Patent Document 3).

  As a method for forming a fine structure on an optical information recording medium, the medium on which the fine structure is formed has a reactive material that changes by laser light irradiation, and the step of forming the fine structure on the medium is performed by air or oxygen gas. Alternatively, a method including at least a laser irradiation step of irradiating a laser beam in a state where the water vapor gas and the reaction material are in contact with each other has been proposed (see Patent Document 4).

  Regarding the structure and manufacturing method of the optical information recording medium, the medium for forming the structure comprises a laminate of a light absorption layer and a heat reaction layer, and the step of forming the structure on the medium is at least for the medium. There has been proposed a structure forming method including a step of irradiating a laser beam and a step of etching the medium (see Patent Document 5).

Convex structure base having fine and highly accurate convex structure on supporting substrate and manufacturing method thereof, heat changeable A layer containing silicon oxide on supporting substrate and heat change generated by absorption of laser beam The layered body in which possible B layers are sequentially provided is irradiated with laser light having a predetermined feeding period, the states of the B layer and the A layer are sequentially changed, and etching processing is performed, so that the A layer and the B layer are formed on the supporting substrate. It has been proposed to use a support substrate of a convex structure base having a convex structure composed of any one of layered layers as a disk and a convex structure as a spiral or concentric circle as a recording medium master. (See Patent Document 6).
JP-A-2005-158191 JP 2005-322365 A JP 2006-004594 A JP 2006-252671 A JP2007-179607 JP2007-242183

PTM is considered to be useful in the production of a high-density master having a capacity of 200 GB / diameter of 120 cm in terms of equipment cost and running cost. Further, the above patent document also shows recording using a ZnS—SiO ₂ film as a resist layer, and ZnS—SiO ₂ is a promising recording material with high resolution.

However, according to experiments, for example, in a two-layer structure composed of a heat-sensitive layer of ZnS-SiO ₂ film and a light absorption layer of Si film described in Patent Document 5, there is a problem in recording a single mark and a space due to PTM. However, it has been found that in the two-layer structure, the light absorption layer has a thick slow cooling structure and the pit shape is inaccurate due to thermal interference when a random pattern such as 1-7 modulation is recorded.

  The inventor thinks that there is a need for improvement in thermal interference during the formation of a conventional convex structure, although good optical recording is possible with a simple film configuration using an inorganic material such as Sn or ZnS.

Accordingly, the problem to be solved by the present invention is to provide a master for producing an optical information recording medium that can improve the thermal interference when forming a convex structure using an inorganic material such as ZnS-SiO ₂ as a heat-sensitive layer. As an example.

  The master for producing an optical information recording medium of the present invention is a master for producing an optical information recording medium having a substrate and a recording layer including a laminate of a recording auxiliary layer and a heat-sensitive layer provided in contact with the substrate. The heat-sensitive layer includes a base material that undergoes a state change upon exposure, and the recording auxiliary layer absorbs light having a wavelength used for exposure and has a thermal conductivity higher than the thermal conductivity of the substrate. It is characterized by comprising.

The method for producing a master for producing an optical information recording medium of the present invention comprises a substrate, and a recording layer including a laminate of a recording auxiliary layer and a heat-sensitive layer provided in contact with the substrate, and the heat-sensitive layer Including a base material that undergoes a state change upon exposure, and the recording auxiliary layer is a method of manufacturing a master for manufacturing an optical information recording medium made of a material that absorbs at least light having a wavelength used for exposure,
Incident from the heat sensitive layer side of the master and irradiating and exposing the recording auxiliary layer; and
Developing the exposed master, and forming a convex pattern structure; and
An electroforming step of plating the convex pattern structure to form a metal master;
An electroforming step of peeling the metal master from the exposed master 11,
Forming a metal material film covering the convex pattern structure after the heat-sensitive layer is exposed and developed in the electroforming step,
The metal material film includes a metal common to the material of the recording auxiliary layer, and the heat-sensitive layer and the metal material film are collectively removed in post-treatment after peeling.

BEST MODE FOR CARRYING OUT THE INVENTION

  Embodiments of the present invention will be described below in detail with reference to the drawings.

  As shown in FIG. 1, a master 11 for manufacturing an optical information recording medium according to the first embodiment includes a circular substrate 12 made of glass, and a recording auxiliary layer 14 and a heat-sensitive layer 16 in contact with the recording auxiliary layer 14 on the substrate 12. And a recording layer 18 is provided. As described above, the master 11 includes the substrate 12 and the recording layer 18 including the laminated body of the recording auxiliary layer 14 and the thermosensitive layer 16 provided in contact with the substrate 12. Data recording is performed on the master 11 having such a structure by focusing and irradiating a laser beam from the heat sensitive layer 16 side.

  The thickness of the substrate 12 is set so that the substrate 12 serves as a base for ensuring the mechanical strength required for the master 11, and the material is glass, SiC, GaN, AlN, or Si. It is possible to use.

  The recording auxiliary layer 14 is made of a material configured to absorb light having a wavelength used for exposure and to have a thermal conductivity higher than that of the substrate 12. Table 1 below shows the thermal conductivity of the materials.

  For example, as shown in FIG. 1, the recording auxiliary layer 14 can be configured to include a heat dissipation layer 141 provided on the substrate 12 side and a light absorption layer 142 provided on the heat sensitive layer 16 side. The performance required for the recording auxiliary layer 14 (particularly the heat dissipation layer 141) requires a large thermal conductivity and a large k (extinction coefficient), and Ag, Au, Al, Cu and alloys thereof are optimal. In the case of the three-layer structure of the recording layer, heat is accumulated in the light absorption layer 142 such as Si and Ge, and excess heat is released by the heat dissipation layer 141 such as Ag and Al. Further, in the case of the two-layer structure of the recording layer, since the heat is accumulated and the excess heat is radiated only by the single recording auxiliary layer 14, random signal recording in a high-density recording area such as 200 GB / 120 cm is performed. Then, a material having a large thermal conductivity such as Ag or Al and a large extinction coefficient k is required.

  The heat dissipation layer 141 has a thermal conductivity higher than that of the substrate 12. For the heat dissipation layer 141, an alloy containing at least one of Ag, Al, Au, and Cu as a main component, for example, AgPdCu is used. The main component referred to here preferably accounts for 50 atomic% or more of the material constituting the recording auxiliary layer 14, and more preferably 80 atomic%.

  The light absorption layer 142 absorbs a laser beam having an exposure wavelength and converts it into heat. The light absorption layer 142 includes at least one of Sb, Si, Ge, and Sn as a main component. The thickness of the light absorption layer 142 is sufficient to change the heat-sensitive layer 16 by spot irradiation with a laser beam, and more heat is required if laminated more than necessary. It is preferably ˜50 nm.

  In forming the three-layer structure by adding the heat dissipation layer 141, the light absorption layer 142 is thinned to form a rapid cooling structure, and thus the film thickness of the light absorption layer 142 is desirably 50 nm or less. Furthermore, when adding the heat dissipation layer 141, it is preferable to employ a material with a small particle size and high-rate film formation in order to suppress an increase in film noise.

The heat-sensitive layer 16 includes a base material that undergoes a state change by energy irradiation, that is, includes a state-change material whose physical properties such as resistance to etching in a later process are changed by the energy of laser beam irradiation as the base material. Has been. The base material of the heat-sensitive layer 16 is not particularly limited as long as it is a material that causes a state change. For example, an oxide, sulfide, nitride, or a combination thereof can be used as a main component. Specifically, the main component is at least one selected from the group consisting of Al ₂ O ₃ , AlN, ZnO, ZnS, GeN, GeCrN, CeO ₂ , SiO, SiO ₂ , SiN, Ta ₂ O ₅ and SiC. It is preferable to do. The heat sensitive layer 16 is preferably a mixture of a sulfide and at least one selected from the group consisting of silicon oxide, zircon oxide, and niobium oxide. For example, another compound such as ZrO ₂ or Nb ₂ O ₅ can be mixed instead of the SiO ₂ mixed component. Furthermore, it is more preferable that the heat-sensitive layer 16 is mainly composed of a mixture of ZnS—SiO ₂ , and SiO ₂ can be in a composition ratio of 5 mol% to 90 mol%, and is preferably 5 mol% to 30 mol%.

  The recording auxiliary layer 14 is a layer that promotes the reaction of the heat-sensitive layer that is in contact therewith, and when the laser light having a predetermined writing power or higher is irradiated, the heat-sensitive layer 16 is partially or entirely formed by the converted heat. Thus, the latent image is formed by a state change (for example, the transition from amorphous to crystallization).

  Moreover, the film thickness of the thermosensitive layer 16 is not particularly limited, but is preferably 5 to 200 nm. When this film thickness is less than 5 nm, even if there is a sufficient change in the state of the base material, the entire layer cannot be expected to have sufficient resistance to subsequent etching. On the other hand, if the film thickness exceeds 200 nm, the film formation time may be prolonged and the productivity may be reduced, and further, cracks may be generated due to the residual stress of the heat sensitive layer 16. It is also conceivable that a portion of the recording auxiliary layer 14 that is not affected by heat remains.

  Next, an example of a method for manufacturing an unrecorded blank master will be described.

  First, the heat dissipation layer 141 is formed on a flat circular substrate 12 such as glass. For example, a vapor deposition method can be used to form the heat dissipation layer 141. Examples of such a vapor phase growth method include a vacuum deposition method and a sputtering method.

  Next, the recording auxiliary layer 14 is configured by laminating and forming the light absorption layer 142 on the heat dissipation layer 141. This light absorption layer 142 can also be formed by vapor phase growth in the same manner as the heat dissipation layer 141. Further, the heat-sensitive layer 16 on the light incident side is formed on the light absorption layer 142 of the recording auxiliary layer 14. The heat sensitive layer 16 can also be formed using a vapor phase growth method. This completes the production of the blank master.

  Next, a method for producing a master for a high-density optical disk using the blank master will be described.

  As shown in FIG. 2, as a laser cutting process, a laser blank LB having a predetermined NA, wavelength, and output is incident on the rotating blank master 11 from the heat-sensitive layer 16 side, and the recording auxiliary layer 14 is irradiated and exposed. .

  By such irradiation with the laser beam LB, the irradiated portion of the recording auxiliary layer 14 is heated by the laser beam LB, affecting the portion of the heat sensitive layer 16 that is in contact with the heated portion, and partially or totally changing the state (for example, The latent image laM is formed by transition from amorphous to crystal). The physical property of the part where the latent image is formed is in a state sufficiently different from the physical property of the other part (unrecorded area). Therefore, development can be performed due to the difference in etching rate between the latent image portion and the other portions. As a result, a latent image pattern corresponding to the desired land and groove of the optical disk is formed on the heat-sensitive layer 16 on the glass substrate 12.

  Next, as shown in FIG. 3, as a development process, the exposed master 11 is mounted on a developing device (not shown), the master 11 is developed to remove the heat-sensitive layer 16 other than the latent image laM portion, and exposure is performed. A convex pattern corresponding to a signal to be recorded is provided on the master 11, and a development master 11 (master for manufacturing an optical information recording medium) composed of a substrate 12 and a convex pattern structure is obtained.

  Next, as an electroforming process, as shown in FIG. 4, a conductive film CM such as nickel or silver is formed on the convex pattern heat-sensitive layer 16 of the development master 11 by a film forming method such as sputtering or vapor deposition. Next, as shown in FIG. 5, a thick plating layer 105 (metal master) is formed by depositing and plating a metal such as nickel on the uneven pattern of the master 11 by plating.

  Next, as shown in FIG. 6, after the metal master 105 is peeled from the master 11, the heat-sensitive layer 16 and the conductive film 3 such as silver remaining on the metal master 105 by acid and / or alkali treatment in a post-processing step. The disc stamper 106 is obtained by trimming and shaping. Here, for example, when Al or Al alloy (Al-Ti or the like) is adopted for the heat dissipation layer 141, in the electroforming process after the heat-sensitive layer 16 is developed by acid treatment to form a convex portion, the heat-sensitive layer 16 If an Al or Al alloy film is formed on the latent image laM as the conductive film CM, and then Ni sputtering and electroforming are performed, the post-treatment after the separation of the master 11 and the metal master 105 is completed with only alkali treatment. be able to. In other words, the conductive film CM (alkali-soluble film) that covers the heat-sensitive layer 16 in the master 11 can be provided, whereby the number of steps can be reduced. That is, in the electroforming process, a conductive film such as nickel or silver is necessarily formed on the convex pattern heat-sensitive layer 16 and nickel electroforming is performed. When the glass master and the Ni master are separated, the Ni master side In addition, a conductive film material or a heat-sensitive layer material may adhere to the surface. At that time, in order to remove these materials, they are removed by contacting with a treatment solution such as a weak acid. However, since Ni is also dissolved in the acid, the surface may be roughened. Therefore, before forming the Ni or Ag conductive film on the convex structure, a slight amount of metal material film soluble in an alkaline solution such as Al (thickness that does not affect the shape of the convex structure). It has been found that, by forming a film (about 5 nm), it is possible to remove the remaining peeling material safely and reliably with an alkaline solution. Further, if Al instead of Ag is used for the heat dissipation layer 141, even if this Al film is brought from the glass master side to the Ni master side, there is an effect that it can be treated only with the alkaline solution. For example, an acid-soluble film includes an Al film, an Ag film, a nickel film, and a sulfide film, and an alkali-soluble film includes an Al film and an Si film. Thus, if the convex structure is covered with a metal common to the material of the recording auxiliary layer and soluble, the number of steps can be reduced.

  Then, the disc stamper 106 is mounted on a mold of an injection molding apparatus, the mold is closed to form a cavity, and after molten resin such as polycarbonate (PC) is injected into the cavity, the mold is cured and the mold is removed. By taking out, an optical disk substrate to which the unevenness of the disk stamper 106 is transferred is obtained.

(Example 1)
A blank master was produced as follows. First, a glass substrate having a diameter of 120 mm was set in a sputtering apparatus, and an Ag—Pd—Cu heat dissipation layer having a film thickness of 80 nm, an Si light absorption layer having a film thickness of 30 nm, and a ZnS— film having a film thickness of 50 nm were formed on the substrate. a mixture of SiO ₂ and heat-sensitive layer made of (SiO ₂ composition ratio 20 mol%) were sequentially formed by sputtering.

  Information was recorded on the blank master as follows. Laser beam exposure (wavelength 405 nm), linear velocity constant, track pitch 160 nm, 2T pit length 75 nm, 1-7PP modulation (channel clock period is T, combination of convex pits and spaces 2T to 8T in length) Modulation) random pattern recording was performed. Under this condition, a density equivalent to 100 GB of the optical disk was obtained. A single mark and space pattern was also recorded.

  The exposed master was immersed and developed with a 1% aqueous sulfuric acid solution.

  After the development, the master was washed with pure water and dried by air blow to remove the unexposed part, leaving the exposed part as a convex pattern, and the glass master of Example 1 was obtained.

  A reflective film of Ni and Ag was formed on the convex pattern surface of the glass master. Thereafter, an electroforming process was performed with a reflective film Ni or the like. Then, it peeled and produced Ni original disk.

  The Ni master was first subjected to acid treatment, then alkali treatment, and then acid treatment to obtain a forming Ni master.

(Example 2)
A blank master was prepared with the substrate, the light absorption layer, and the heat-sensitive layer being the same as in Example 1 except that the heat dissipation layer was made of Al-Ti with a thickness of 80 nm, and 1-7PP modulation pattern recording was performed in the same manner as in Example 1. After development, a glass master disk of Example 2 was obtained.
(Comparative example)
A blank master was produced under the same conditions as in Example 1 except that a heat-absorbing layer was not provided and a Si light-absorbing layer having a thickness of 100 nm was formed, and a 1-7PP modulation pattern was prepared in the same manner as in Example 1. Recording and single mark space recording were performed, and after development, a glass master disk of a comparative example was obtained.
(Evaluation)
7 and 8 are SEM photographs of glass masters on which 1-7 modulation random pattern recording and single mark space recording of Example 1 were performed, respectively.

  FIG. 9 is an SEM photograph of the glass master disc on which a 1-7 modulation random pattern was recorded in Example 2.

  FIGS. 10 and 11 are SEM photographs of glass masters on which 1-7 modulation random pattern recording and single mark space recording of a comparative example were performed, respectively. As apparent from FIG. 11, thermal interference occurs and normal recording cannot be performed.

  As is clear from FIGS. 8 and 11, in Example 1 and the comparative example, there was no problem in single mark space recording.

  As is clear from FIGS. 7, 9 and 10, inaccurate convex pits are recorded due to thermal interference when a random pattern (pattern of long pits, short spaces, short marks, etc.) is recorded. In the example, by adding a heat dissipation layer between the glass substrate and the light absorption layer, it becomes possible to effectively release excess heat, and not only repeated recording of single marks and spaces, but also random patterns were recorded. It was possible to create an accurate and stable convex pit. It can be seen that the heat dissipation layers Ag-Pd-Cu and Al-Ti of Examples 1 and 2 exhibit the effect of improving the heat interference of the heat sink (heat dissipation).

Furthermore, in Example 2, in addition to the effect of improving thermal interference, improvement of treatment after peeling could be achieved. That is, since Al—Ti is adopted for the heat dissipation layer, in the Ni master manufacturing process after developing the heat sensitive layer ZnS—SiO ₂ to form the convex pit, an Al alloy is formed on the convex pit heat sensitive layer. After forming, and then performing Ni sputtering and electroforming, the post-treatment after peeling the substrate and the Ni master is only alkali treatment (Since Si and Al-Ti are soluble in alkali, the same treatment is possible. ) And the number of processes could be reduced.

Thus, as shown in FIG. 2, ZnS—SiO ₂ which is the material of the heat sensitive layer 16 does not absorb the light having the wavelength used for exposure, and thus almost does not absorb the laser beam LB. For this reason, a light absorption layer 142 that absorbs light more than the heat-sensitive layer material such as Si is required, and the light absorption layer 142 absorbs light and converts it into heat to thermally change the heat-sensitive layer 16.

  It is preferable that light is changed into heat in the recording auxiliary layer (light absorption layer 142, Si layer, etc.), but heat is no longer necessary after applying the necessary change to the heat sensitive layer 16, so it is desirable to cool immediately. . However, in the light absorption layer 142 such as the Si layer, the temperature gradually decreases due to its property and the heat gradually diffuses in the vertical and horizontal directions, so that convex pits having a target size are recorded. It becomes difficult and it becomes an uneven convex pit.

  Therefore, by further providing a heat dissipation layer 141 (Ag, Al, Au, Cu or an alloy containing them as a main component), by suppressing the promotion of the cooling and thermal diffusion, the convex portions having the same size as the target. It becomes easy to form pits.

Example 3
A blank master was produced in the same manner as in Example 1 except that the recording auxiliary layer was not divided into a heat dissipation layer and a light absorption layer, and Ag—Pd—Cu having a film thickness of 20 nm was used. A modulation pattern was recorded, and after development, a glass master disk of Example 3 was obtained. In Example 3, the same effect as in Examples 1 and 2 was confirmed. The Ag-Pd-Cu recording auxiliary layer plays a role of heat sink (heat dissipation) and light absorption, and releases the excess heat when exposing a high-density random pattern, and has the function of producing accurate and stable convex pits. Have.

  Therefore, even in a three-layer structure composed of a heat-sensitive layer, a light absorption layer, and a heat dissipation layer, or a two-layer structure composed of a heat-sensitive layer and a recording auxiliary layer, the recording auxiliary layer absorbs light having a wavelength used for exposure. If it is made of a material having a thermal conductivity higher than that of the substrate, a stable pit shape can be obtained even if a random pattern is recorded and developed.

As shown in FIG. 12, in the case where the recording auxiliary layer 14 in which the light absorption layer (Si layer or the like) is omitted is a single layer structure, the ZnS-SiO ₂ heat sensitive layer 16 is developed (etched) with an acid. When 14 is a single metal layer, the recording auxiliary layer itself dissolves, and there is a concern about the problem of film floating or peeling of the ZnS-SiO ₂ convex structure itself from the glass substrate. If a low-concentration sulfuric acid solution is used, since the concentration of the solution itself is low, there is no problem with any metal. Furthermore, the problem can be completely solved by using Au and an Au alloy for the recording auxiliary layer 14. .

It is a schematic fragmentary sectional view which shows the original disc for optical information recording medium manufacture concerning the 1st example of embodiment by this invention. It is a general | schematic fragmentary sectional view for demonstrating the manufacturing method of the master for optical information recording medium manufacture of embodiment by this invention. It is a general | schematic fragmentary sectional view for demonstrating the manufacturing method of the master for optical information recording medium manufacture of embodiment by this invention. It is a general | schematic fragmentary sectional view for demonstrating the manufacturing method of the master for optical information recording medium manufacture of embodiment by this invention. It is a general | schematic fragmentary sectional view for demonstrating the manufacturing method of the master for optical information recording medium manufacture of embodiment by this invention. It is a general | schematic fragmentary sectional view for demonstrating the manufacturing method of the master for optical information recording medium manufacture of embodiment by this invention. It is a SEM photograph of the glass original disc by which 1-7 modulation random pattern recording of Example 1 by this invention was recorded. It is a SEM photograph of the glass original disc by which single mark space recording of Example 1 by the present invention was recorded. It is a SEM photograph of the glass master disc on which 1-7 modulation random pattern recording of Example 2 by the present invention was recorded. It is a SEM photograph of the glass original disc by which 1-7 modulation random pattern recording of the comparative example was carried out. It is a SEM photograph of the glass original disc by which single mark space recording of the comparative example was carried out. It is a general | schematic fragmentary sectional view which shows the original disc for optical information recording medium manufacture concerning the 2nd example of embodiment by this invention.

Explanation of symbols

11 Master 12 Substrate 14 Recording auxiliary layer 16 Heat sensitive layer 18 Recording layer 141 Heat radiation layer 142 Light absorption layer LB Laser beam
laM latent image
CM conductive film

Claims (13)

A master for manufacturing an optical information recording medium, comprising: a substrate; and a recording layer including a laminate of a recording auxiliary layer and a thermosensitive layer provided in contact with the substrate,
The heat-sensitive layer includes a base material that undergoes a state change upon exposure, and the recording auxiliary layer is made of a material that absorbs light having a wavelength used for exposure and has a thermal conductivity higher than that of the substrate. A master for producing optical information recording media.   The recording auxiliary layer is provided on the substrate side and has a heat dissipation layer having a thermal conductivity higher than that of the substrate, and the light absorption layer provided on the heat sensitive layer side and absorbs light having a wavelength used for exposure. The master for manufacturing an optical information recording medium according to claim 1, further comprising a layer.   3. The master for manufacturing an optical information recording medium according to claim 2, wherein the heat dissipation layer is made of an alloy containing at least one of Ag, Al, Au, and Cu as a main component.   4. The master for producing an optical information recording medium according to claim 2, wherein the light absorption layer contains at least one of Sb, Si, Ge, and Sn as a main component.   2. The master for producing an optical information recording medium according to claim 1, wherein the recording auxiliary layer contains at least one of Ag, Al, Au, and Cu as a main component.   The heat-sensitive layer is a mixture of a sulfide and at least one selected from the group of silicon oxide, zircon oxide, and niobium oxide, according to any one of claims 1 to 5. Master for manufacturing optical information recording media. The master for manufacturing an optical information recording medium according to claim 6, wherein the heat-sensitive layer is made of ZnS-SiO ₂ and contains 5 to 30 mol% of SiO ₂ .   The master for producing an optical information recording medium according to any one of claims 1 to 7, wherein the substrate is made of any one of glass, SiC, GaN, AlN, and Si.   The master for producing an optical information recording medium according to claim 1, further comprising an alkali-soluble film that covers the heat-sensitive layer after the heat-sensitive layer is exposed and developed.   The optical information recording medium production according to any one of claims 1 to 8, wherein the common metal of the metal material film is a metal that is dissolved by a treatment by contact with the same alkali or acid. Master. A recording layer including a substrate, and a recording auxiliary layer provided on and in contact with the substrate, and a recording layer including a heat sensitive layer, wherein the heat sensitive layer includes a base material that undergoes a state change upon exposure, and the recording auxiliary layer Is a method of manufacturing a master for manufacturing an optical information recording medium made of a material that absorbs at least light having a wavelength used for exposure,
Incident from the heat sensitive layer side of the master and irradiating and exposing the recording auxiliary layer; and
Developing the exposed master, and forming a convex pattern structure; and
An electroforming step of plating the convex pattern structure to form a metal master;
An electroforming step of peeling the metal master from the exposed master 11,
Forming a metal material film covering the convex pattern structure after the heat-sensitive layer is exposed and developed in the electroforming step,
The optical information recording, wherein the metal material film contains a common metal that is soluble with the material of the recording auxiliary layer, and the heat-sensitive layer and the metal material film are collectively removed in post-treatment after peeling. A method for producing a master for producing a medium.   12. The method of manufacturing a master for manufacturing an optical information recording medium according to claim 11, wherein the soluble common metals of the metal material film are the same metal.   12. The production of a master for producing an optical information recording medium according to claim 11, wherein the soluble common metal of the metal material film is a metal which is dissolved by a treatment by contact with the same alkali or acid. Method.

Images