JP2003173585A - Phase change optical disk and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress variance in product quality by minimizing the influence of gas, etc., adsorbed to a substrate of polycarbonate, etc., by modifying a filming process for a recording layer in sputtering without altering facilities nor adding new facilities. <P>SOLUTION: A manufacturing method for a phase change optical recording medium including as constitution elements at least a substrate which is left in an atmosphere after resin molding, a 1st protection layer, a recording layer, a 2nd protection layer, and a reflecting heat radiation layer which are laminated on the substrate by vacuum film deposition, and a UV-setting resin layer which is deposited on the top surface side of the reflecting heat radiation layer by coating and setting is characterized in that the quality of the phase change optical recording medium is stabilized by minimizing the influence of adsorbed gas in the substrate by adjusting at least one of the sputtering electric power for the recording film laminated by the vacuum film deposition, the wait time up to the start of sputtering, and the time for which the substrate is left in the atmosphere after the resin molding. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical recording medium, in particular, a phase change in which a recording layer material undergoes a phase change by irradiating a light beam to record / reproduce information and can be rewritten. TECHNICAL FIELD The present invention relates to a method for manufacturing an optical recording medium and an optical recording medium.

[0002]

2. Description of the Related Art As one of optical recording media capable of recording / reproducing and erasing by irradiation of a laser beam, a so-called phase change type optical recording medium utilizing a transition between a crystalline-amorphous phase or a crystalline-crystalline phase is often used. Are known. Overwriting with a single beam, which is especially difficult with magneto-optical memory, is easy, and the optical system on the recording / reproducing device side is simpler. CD-RW, DVD-RW, DVD-R
AM etc. are commercialized. With these recording media,
Further densification and higher linear velocity are expected to enable more information to be recorded faster.

Many phase-change type optical recording media such as CD-RW have a multi-layer structure in which the upper and lower sides of the recording layer are sandwiched by dielectric layers. Usually, as a method for producing these optical recording media, a method for depositing each layer by sputtering on a substrate such as polycarbonate is used.

In this phase change type optical recording medium, if the gas or the like adsorbed on the substrate such as polycarbonate in the atmosphere is taken into the film during sputtering, the film characteristics are deteriorated.
Minimizing the influence of the gas adsorbed on the substrate such as polycarbonate is a very important issue for suppressing variations in product quality.

Conventionally, as a means for minimizing the influence of the gas adsorbed on the substrate, the forming process and the sputtering process are connected in-line to shorten the time that the substrate before sputtering stays in the atmosphere as much as possible. And how to prevent the effects of
In Japanese Patent Laid-Open No. 6-195706, a method of preventing the influence of adsorbed gas or the like by changing the shape of the substrate holder of the in-line type sputtering apparatus, and in Japanese Patent Laid-Open No. 6-333274, the degree of vacuum of the substrate is 0.5 Pa. 3 in the following atmosphere
A method of preventing the influence of gas adsorbed on the substrate by leaving it for 0 minutes or more has been proposed.

However, in the above method of changing the shape of the sputter substrate holder or leaving the substrate in a vacuum atmosphere before sputtering, it is necessary to modify the sputtering apparatus and newly install a vacuum chamber for pretreatment of sputtering. However, this will increase the cost of disk production.

[0007]

SUMMARY OF THE INVENTION Therefore, in view of the above-mentioned prior art, the object of the present invention is to change the film forming process of the recording layer at the time of sputtering without modifying the equipment or adding new equipment. By doing so, the influence of gas or the like adsorbed on the substrate such as polycarbonate is minimized, and variation in product quality is suppressed.

[0008]

Means for Solving the Problems The above-mentioned problems are (1) of the present invention, "at least a substrate left in the air after resin molding and a first protective layer formed on the substrate by vacuum film formation. A layer, a recording layer, a second protective layer, a reflection heat radiation layer, and a UV-curable resin layer formed by coating and curing on the upper surface side of the reflection heat radiation layer as constituent elements, At least one of the sputtering power of the recording layers formed by vacuum film formation, the waiting time until the start of sputtering, and the time for leaving the substrate in the atmosphere after resin molding.
By adjusting one or more of them, the influence of the adsorption gas on the substrate is minimized, and the quality of the phase-change optical recording medium is stabilized. "(2)
"The sputtering power of the recording layer is 0.4 kW or more and 10 kW
The method for producing a phase change optical recording medium according to item (1) above, characterized in that: (3) "the waiting time until the start of sputtering is 3.0 seconds or less. And (4) "The time for which the substrate is left in the air after the resin molding is set to 3 minutes or more." The method for producing a phase change type optical recording medium according to the item (1) ”,
(5) “The target material of the recording layer is Ag and / or Ge, In and / or Ga and / or B
i, Sb, Te as a main component, The method for producing a phase change type optical recording medium according to the item (1) ”,
(6) “As a constituent element of the phase-change recording layer, Ag and / or Ge, In and / or Ga and / or Bi, Sb, Te are contained, and their composition ratios (A
g and / or Ge) _α (In and / or Ga and / or Bi) _β Sb _γ Te _δ (α, β, γ, δ are atomic%), when α + β + γ + δ = 100,

[0009]

[Formula 5] 0.1 ≦ α ≦ 7

[0010]

[Equation 6] 1 ≦ β ≦ 15

[0011]

(7) 61 ≦ γ ≦ 85

[0012]

[Equation 8] 20 ≦ δ ≦ 30, which is achieved by the method for producing a phase change type optical recording medium according to the item (5).

Further, the above-mentioned problem is characterized in that it is manufactured by using at least one manufacturing method according to any one of (7) "(1) to (6) of the present invention. And a phase change type optical recording medium.

There are the following two methods for minimizing the effect of gas adsorbed on a substrate such as polycarbonate during sputtering. One is to increase the film formation speed to reduce the sputtering time, and the other is to reduce the time from the transfer of the disk into the process chamber to the start of sputtering.

In the present invention, a substrate that has been sufficiently left in the atmosphere after resin molding, and a first protective layer, a recording layer, a second protective layer and a reflective heat dissipation layer that are laminated and formed on the substrate by vacuum film formation. In a method for manufacturing a phase-change optical recording medium including, as a constituent element, a UV curable resin layer formed by coating and curing on the upper surface side of the reflection and heat dissipation layer, sputtering power of recording layers laminated by vacuum film formation, The problem is solved by adjusting at least one of waiting times until the start of sputtering.

When the sputtering power of the recording layer is larger than 10 kW, the sputtering time becomes too short and the discharge stability of the film formation is liable to be deteriorated. On the contrary, when it is less than 0.4 kW, the effect of the present invention is obtained. Can't get

The waiting time before the start of sputtering is 3.
When it is longer than 0 seconds, the influence of the adsorption gas adsorbed on the substrate such as polycarbonate cannot be ignored. Preferably,
This is a method for producing a phase-change optical recording medium in which the time for which the substrate is left in the air after resin molding is set to 3 minutes or more.

Preferably, the target material of the recording layer is Ag and / or Ge, In and / or Ga.
And / or Bi, Sb, Te as a main component, which is a method for manufacturing a phase-change optical recording medium.

Particularly preferably, Ag and / or Ge, In and / or Ga and / or Bi, Sb and Te are contained as constituent elements of the phase change recording layer, and the respective composition ratios (Ag and / or Or Ge)
_α (In and / or Ga and / or Bi) _β S
b _γ Te _δ (α, β, γ, δ are atomic%) is α + β + γ
When + δ = 100,

[0020]

[Formula 9] 0.1 ≦ α ≦ 7

[0021]

[Equation 10] 1 ≦ β ≦ 15

[0022]

(11) 61 ≦ γ ≦ 85

[0023]

## EQU12 ## A method of manufacturing a phase change optical recording medium, characterized in that 20 ≦ δ ≦ 30.

[0024]

EXAMPLES The present invention will be specifically described below with reference to examples. After the resin molding, the first protective layer and the second protective layer were coated with Z on a polycarbonate substrate which was left in the air for 8 hours.
nSSiO ₂ is used, and the film thickness is 86 nm and 30 n, respectively.
m. The recording layer was made of Ag _4.0 In _6.0 Sb _61.0 Te _{29.0 and} had a film thickness of 19 nm. AlTi for the reflective heat dissipation layer
(1.0 wt%) was used and the thickness was set to 140 nm. As a result, substrate / ZnSSiO ₂ (83 nm) / recording layer (19 nm) / ZnSSiO ₂ (30 nm) / AlTi
A layer structure of (140 nm) was formed. The film forming conditions for the recording layer are shown below for each example.

(Example 1) Ar: 10 sccm, Power: 0.4 kW, waiting time until the start of sputtering: 2.5 s

(Example 2) Ar: 10 sccm, Power: 0.8 kW, waiting time before starting sputtering: 2.5 s

(Example 3) Ar: 10 sccm, Power: 0.4 kW, waiting time before the start of sputtering: 0.5 s

(Example 4) Ar: 10 sccm, Power: 0.8 kW, waiting time before the start of sputtering: 0.5 s

Next, after resin molding, ZnSSiO ₂ was used for the first protective layer and the second protective layer on a polycarbonate substrate that had been left in the air for 1 minute (that is, immediately after molding), and the film thickness was 86 nm. , 30 nm. The recording layer is made of Ag _4.0 In _6.0 Sb _61.0 Te _{29.0 and} has a film thickness of 1
9 nm. AlTi (1.0 wt.
%) Was used to make the thickness 140 nm. As a result, the substrate / ZnSSiO ₂ (83 nm) / recording layer (19 nm) /
ZnSSiO ₂ (30 nm) / AlTi (140 nm)
The layer structure was formed. The film forming conditions for the recording layer of the comparative example are shown below.

(Comparative Example 1) Ar: 10 sccm, Power: 0.4 kW, waiting time before starting sputtering: 2.5 s

Incidentally, Comparative Example 1 corresponds to a disk prepared by the prior art in which the influence of adsorbed gas or the like is prevented by minimizing the time the substrate before sputtering stays in the atmosphere.

The transition linear velocities of the samples prepared in the above Examples and Comparative Examples were measured and the data were compared. The results are shown in Table 1.

[0033]

[Table 1] Comparing the results of Example 1 and Example 2 and Example 3 and Example 4, it can be seen that changing the sputter power has the effect of preventing the influence of the adsorption gas of the substrate. In addition, comparing the results of Example 1 and Example 3, and Example 2 and Example 4, it can be seen that the effect of the adsorption gas of the substrate is prevented by shortening the waiting time until the start of sputtering. . In conclusion, from the results of Examples 1 to 4 and Comparative Example 1 described above, by optimizing the sputtering power of the recording layer and the waiting time until the start of sputtering, the influence of the adsorption gas of the substrate is minimized, It can be seen that the same result as that of Comparative Example 1 (sample prepared by the conventional technique) is obtained.

[0034]

As is clear from the detailed and specific invention, according to claim 1 of the present invention, a substrate left in the atmosphere after resin molding and a film formed on the substrate by vacuum film formation. Phase change optical recording including a first protective layer, a recording layer, a second protective layer and a reflective heat dissipation layer formed, and a UV curable resin layer formed by coating and curing on the upper surface side of the reflective heat dissipation layer as constituent elements. In the medium manufacturing method, by adjusting at least one of the sputtering power of the recording layers laminated by vacuum film formation, the waiting time until the start of sputtering, and the time for which the substrate is left in the air after resin molding is adjusted. By minimizing the influence of the adsorption gas on the substrate, the quality of the phase change optical recording medium can be stabilized. According to claim 2 of the present invention, in the method for producing the phase-change optical recording medium according to claim 1, the sputtering power of the recording layer is 0.4 kW or more.
By setting it to kW or less, the quality of the phase change optical recording medium can be stabilized. According to claim 3 of the present invention, in the method for manufacturing a phase-change optical recording medium according to claim 1, the waiting time until the start of sputtering is set to 3.0 seconds or less to improve the quality of the phase-change optical recording medium. Can be stabilized. According to claim 4 of the present invention, in the method for producing the phase-change optical recording medium according to claim 1, after resin molding,
The quality of the phase-change optical recording medium can be stabilized by setting the time for leaving the substrate to stand in the atmosphere for 3 minutes or more. According to claim 5 of the present invention, in the method of manufacturing the phase-change optical recording medium according to claim 1, the target material of the recording layer is Ag and / or Ge, In and / or G.
By using a and / or Bi, Sb, or Te as the main component, the quality of the phase change optical recording medium can be stabilized. Further, according to claim 6 of the present invention, in the claim 5, as the constituent elements of the phase-change recording layer, Ag and / or
Or Ge, In and / or Ga and / or B
It contains i, Sb, and Te, and their composition ratios (Ag
And / or Ge) _α (In and / or Ga and / or Bi) _β Sb _γ Te _δ (α, β, γ, δ are atomic%), when α + β + γ + δ = 100,

[0035]

[Formula 13] 0.1 ≦ α ≦ 7

[0036]

[Equation 14] 1 ≦ β ≦ 15

[0037]

Equation 15 61 ≦ γ ≦ 85

[0038]

By setting 20 ≦ δ ≦ 30, the quality of the phase change optical recording medium can be stabilized. Further, according to the seventh aspect of the present invention, by using the manufacturing method according to the first to sixth aspects, it is possible to produce a phase change type optical recording medium having excellent productivity and stable product quality.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a phase change recording medium of the present invention.

[Explanation of symbols]

1 substrate 2 First protective layer 3 recording layers 4 Second protective layer 5 Reflective heat dissipation layer 6 UV curable resin layer

Claims (7)

[Claims] 1. At least a substrate left in the air after resin molding, and a first protective layer, a recording layer, a second protective layer and a reflective heat dissipation layer which are laminated on the substrate by vacuum film formation, In a method of manufacturing a phase-change optical recording medium including a UV curable resin layer formed by coating and curing on the upper surface side of the reflection and heat dissipation layer, sputtering power and sputtering of recording layers formed by vacuum film formation. Waiting time to start,
The characteristics of the phase change type optical recording medium are stabilized by minimizing at least one of the time for which the substrate is left in the atmosphere after the resin molding to minimize the influence of the adsorption gas on the substrate. And a method for manufacturing a phase change optical recording medium. 2. The sputtering power of the recording layer is 0.4 kW.
The method for producing a phase-change optical recording medium according to claim 1, wherein the power is 10 kW or less. 3. The waiting time until the start of the sputtering is 3.
The method for producing a phase-change optical recording medium according to claim 1, wherein the time is 0 second or less. 4. The method for producing a phase-change optical recording medium according to claim 1, wherein after the resin molding, the substrate is left in the atmosphere for 3 minutes or more. 5. The phase change type according to claim 1, wherein the target material of the recording layer contains Ag and / or Ge, In and / or Ga and / or Bi, Sb, Te as a main component. Optical recording medium manufacturing method. 6. Ag as a constituent element of the phase change recording layer
And / or Ge, In and / or Ga and /
Or Bi, Sb, Te, and the composition ratios (Ag and / or Ge) _α (In and / or Ga and / or Bi) _β Sb _γ Te _δ (α, β,
γ and δ are in atomic%), and when α + β + γ + δ = 100, the following equation is obtained: 0.1 ≦ α ≦ 7 Equation 2 1 ≦ β ≦ 15 Equation 3 61 ≦ γ ≦ 85 Equation 4 The method for producing a phase change optical recording medium according to claim 5, wherein 20 ≦ δ ≦ 30. 7. A phase-change optical recording medium manufactured by using at least one manufacturing method according to claim 1. Description: