TW200411655A - A structure for rewritable multi-level phase-change optical - Google Patents

Abstract

The invention provides a structure of multi-level reflection for rewritable phase-change optical recording medium. The characteristic is that the material of the recording layer of the structure is InxSbyTez, and the variable x is among 5.1~35.0(%), the variable y is among 57.5~71.7(%), and the variable z is among 7.5~23.2(%). This material has improvements which are high reflection ratio, discriminating partial recrystallization, high phase-change rate, and easily mark edge control, so it is suitable for multi-level reflection optical recording disk to increase data density, and the storage capacity of the recording medium.

Description

200411655 V. Description of the invention (1)-"Technical field to which the invention belongs" The present invention relates to a Phase-change Erasable Opti cal Recording Media, and particularly refers to Structure of a phase-change optical recording medium capable of increasing the recording density per unit area by multi-order reflectance. [Previous technology] With the development of multimedia, the requirements for the capacity and quality of recording media

"Do not increase f" and the rewritable phase-change optical discs that are just emerging in the market today, because they meet the characteristics of high capacity, high quality, low cost and portability, and have the function of writable erasing. Application fields and markets. The phase change disc uses laser light to illuminate the disc, so that the material of the recording layer is switched between the crystalline phase and the amorphous phase structure. The high reflectivity of the crystalline phase and the low reflectance of the amorphous phase are used to identify the 0,1 signal. . The bit writing system uses high-power short-pulse laser irradiation to locally melt the disc and quickly cool it to form an amorphous phase structure. The bit-wiping is irradiated with a low-power laser pulse.

The disc is partially annealed and crystallized, and a lower power laser is used to detect the bit reflectance to read the bit. The material of the recording layer of a conventional phase-change optical disc has a small reflectance contrast, and does not have sufficient reflectance contrast for the use of multi-level reflectivity disc (Mu i t i-Level Recording) technology. At present, the multi-order reflectivity disc technology using the new encoding and recording technology to increase the recording capacity is being developed. It can be roughly divided into:

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V. Description of the invention (2) 1. Pit Depth Modulation (PDM) developed by Calimetric, USA; 2. Run-Length-Limited Modulation developed by University of Arizona. In order to correspond to the new recording technology used in this Multi-Level Recording, the type of recording track will be different from the traditional recording track with only two-order reflectance, and at least the second-order or third-order reflectance is required to achieve the signal classification ( Level) to increase the recording density per unit area. As for how to form multi-order reflectance, the current practice can be roughly divided into two types: First, the use of recording mark size effects, such as TMMR (tangential mark-size modulation by recrystallization) technology, writes smaller than laser light spots and has different lengths. Recording tracks, and MRWM (mark radial width modulation) are recording tracks of a fixed length but different widths. During reading, the reflectivity of the laser light spot within a fixed time will be different due to the difference in the size of the recorded traces. First, by using the characteristics of the partial crystal material, by controlling the writing power, The materials form different degrees of crystals to obtain different reflectances. At present, there are no embodiments in the market that can partially crystallize materials for rewritable phase change optical discs. Based on this, the present invention proposes a new recording layer material with partial crystallization effect for use in future multi-order reflectivity optical discs using MU1U technology.

200411655 V. Description of the invention (3) '-[Summary of the invention]

FIG. 1 shows the structure of a rewritable phase t-change type optical recording medium according to the present invention. The substrate 10 is a polycarbonate (P, PVC, or PMMA (Poly Mj ^ yl Methacrylate)) material having a thickness of 0.6 mm or more, and the depth of the groove 100 is 30 to 60 (nm). The range of the rail groove 100 degree is 0.25 ~ 0.74 (mm). If the thickness of the substrate 10 is 0.6, you must apply a layer of adhesive by screen printing, and then leave a blank (Dummy ) And this film are glued to form an optical disc with a thickness of κ 2 bands. The insulating layer 1 ± 2 is used to effectively separate the substrate 10 from the recording layer 14 to prevent the recording operation from destroying the substrate 10 , Which can use A1 203, AIN, ZnS (80%)-SiO2 (20%) and other materials with a thickness ranging from 70 to 12 (run), where

The composition ratio of ZnS to Si02 is 8: 2. The recording layer 14 of the present invention uses an InxSbyTez material, where the value of the variable x ranges from 5.j to 35.0 (at%), the value of the variable y ranges from 57.5 to 71.7 (at%), and the value of the variable z ranges from 7.5 to 23.2 (at%), and its thickness ranges from 10 to 30 (nm). The heat retaining layer 16 is used to store the laser energy when the laser wavelength is irradiated in the red light band (1 = 650 nm or 780 nm), and to provide the materials needed for the material of the recording layer 14 to change from amorphous to crystalline. It can use materials such as A1 203, A1N, ZnS (80%)-Si02 (20%) and other materials with a thickness ranging from 10 to 20 (nm), where the composition ratio of ZnS to Si 0 is 8: 2. The reflective layer 18 is made of gold, silver, copper, aluminum or other alloy materials with a thickness ranging from 80 to 120 (nm). The best embodiment of the rewritable phase change type optical recording medium of the present invention ′ is a method of co-plating the two alloy handles of In50Sb50 and Sb70Te30.

200411655 V. Description of the invention (4) Preparation. By changing the power A or DC magnetic flux sputtering applied to two dry alloys of In50Sb50 and Sb70Te30, the power A is small and the coating composition is changed to prepare the required I nxSbyTez. alloy composition~. In addition, the insulation layer 1, 2, the heat-retaining layer 16, and the reflective layer 18 can also be made by a sputtering machine, and the thickness thereof can be controlled by sputtering electroplating and money plating time. The usable laser of the present invention has a wavelength range of 600 to 780 (nm), and the numerical aperture of the optical lens 13 ranges from 0.55 to 0.70. In order for those skilled in the art to understand the objects and features of the present invention And effects, the following specific embodiments and the accompanying drawings are used to describe the present invention in detail as follows: [Embodiment] The first specific embodiment of the present invention is disclosed below. Selecting a substrate is as follows: PC7 material 'its thickness is 1.2 mm; insulation layer 12 is made of ZnS (80%)-Si02 (20%) material and its thickness is 90nm; recording layer 14 is made of In 23.2 Sb 62 · material' whose thickness is 20nm; heat preservation Layer 16 is made of ZnS (80%)-SiO2 (, 20%) material. Its thickness is 15nm. Reflective layer 18 is made of silver and its thickness is 90nm. The invention uses a sputtering machine to make an insulating layer. 1. The recording layer. 1 4. Thermal insulation f 1 6, Reflective layer 1 8. The thickness is controlled by the sputtering current and sputtering time. The multi-stage reflectivity phase-change optical disc made of I is red laser (1 = 78. ⑽ 'The delta-type machine writes a single-length crystalline record and measures 5 different reflectances, as shown in Figure 2. DETAILED second embodiment Ming for example: Select 1 ◦ substrate: ... generation materials' having a thickness of 1 · 2 mm; insulating layer 12 is ZnS (80%) - Si〇2

Page 9 200411655 V. Description of the invention (5) (20-core material 'its thickness is 90 nm; the recording layer 14 is an In 5.1Sb 71.7Te 23 · 02 material, its thickness is 20 nm; 6 is ZnS (80% SiO 2 (2, U) material; its thickness is 15 nm; the reflective layer 18 is made of silver and its thickness = 90 nm. The present invention uses a sputtering machine to manually create an insulating layer 12, The recording layer 14, thermal insulation ^ 16 and reflective layer 18, and the thickness is controlled by sputtering current and sputtering time. The multi-stage reflectance phase change type optical disc is red laser (K80 nm) The machine writes a single-length crystalline recording trace and measures the reflectance of different g-orders, as shown in Figure 3. The characteristics of the present invention are further summarized as follows: • The recording layer material, crystalline phase and amorphous of the present invention There is a high degree of reflection between the phases: and part of the crystal effect is obvious, and it also has a recording layer with a fast rate of phase change / suitable for multi-order reflectivity optical discs. High performance. Therefore, according to the present invention, the only type of optical discs or rewriteable door personal computers that have been developed in accordance with the present invention, ^ You Feng used the data storage of public-π binary pen or dry computer, and it can also be used by the company and the company's consultants J J to store the f 1 beating shake. It is also suitable for low-cost electronic products. The invention has been limited to the present invention in a preferred embodiment. Anything that ... does not use God and her, when: : Departure from the scope of the present invention, and attach the scope of patent application; Defined by :: The guarantee of the present invention 200411655 Brief description of the diagram [Schematic description of the diagram] Figure 1 is an overwritable phase change homogeneous type Structural diagram of an optical recording medium; Figure 2 is the test results of the first embodiment of the present invention; Figure 3 is the test results of the second embodiment of the present invention. Drawing number description 10 100 11 12 13 14 16 18 substrate Ditch laser insulation layer optical lens recording layer heat preservation layer reflection layer

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Claims (1)

200411655 : A kind of rewritable phase-change optical recording medium junction with multi-order reflectance, which is composed of at least a substrate, two insulation layers, a recording layer, a thermal insulation layer, and a urinary ejection layer. A laser beam generated by a laser beam passing through an optical lens illuminates the recording layer to read the optical recording medium, which is characterized in that: the shell layer is made of Indium SbyTez material, in which the value range of the variable χ; , · ~ 35 · 0 (at%), and the value range of the variable y is 57.5 to 71.7 (at%), and the value range of the variable z is 7.5 to 23 · 2 (μ 幻 The structure of a rewritable phase change optical recording medium with multi-order reflectance as described in item 2 of the patent application in 2.2, where the substrate is pc (Polycarbonate), or PVC, or pMMA (p〇ly Methyl Methacrylate) The thickness of the material is, and the depth of the groove is in the range of 30 to β (nm), and the width of the groove is in the range of 0.25 to 74 (mm). 3. The structure of an overwritable phase, under-type optical recording medium with multi-order reflectance as described in item 1 of the declared patent scope, wherein the insulation layer is A1 2 0 3, or A1N, or the component ratio is 8 · · 2 ZnS-SiO2 material, the thickness of the beans is in the range of 70 ~ 120 (nm). ', 4 · The structure of a rewritable phase change optical recording medium having multi-order reflectance as described in item 1 of the scope of the patent application, wherein the thickness of the recording layer ranges from 10 to 30 (nm). • Writable phase-changeable optical recording green media structure with multi-order reflectance as described in item 1 of the declared patent scope, wherein the heat preservation layer is A 丨 2⑽ Page 12 200411655 VI. Apply for a patent 巳 巳, or A1N, or ZnS_Sl02 material with a composition ratio of 8: 2, the thickness range is 10 ~ 20 (nm) ° 6. As described in the first item of the patent application scope Writable phase-change optical recording medium with multi-order reflectivity-structure 'wherein the reflective layer is gold, or silver, or copper, or aluminum, or other alloy materials' and its thickness ranges from 80 to 120 (nm) 〇7. The structure of a rewritable phase change optical recording medium with multi-order reflectance as described in item 1 of the scope of patent application, wherein the laser has a wavelength range of 600 to 780 (nm). 8. The coverable aperture with multi-order reflectance as described in item 1 is 0 = recording medium structure, where the numerical value Q of the optical lens is from Xinkui 1, 5 ~ 0 · 70. 9 · The coverability with multi-order reflectance as described in item 1 of the phase change type light a of the patent %% is achieved by co-sputtering the structure of the recording medium, wherein the InxSbyTez material is prepared by In50Sb50 material and Sb70Te30 material are produced. Page 13