JP3239145B2 - Method for manufacturing optical information recording medium - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an optical information recording medium such as a magneto-optical disk using a plastic substrate.

[0002]

2. Description of the Related Art In general, a manufacturing process of a magneto-optical disk is performed by a stamper → substrate formation → relaxation of stress in the substrate by annealing →
Vacuum degassing → film formation → cover layer application is performed. Also, the hard coat layer coating step is usually incorporated before annealing or after film formation. CDs and phase change disks are manufactured in substantially the same process.

However, in such a process, since the substrate absorbs water after the substrate is formed, if the dehydration is not sufficiently performed by taking a long time for the vacuum degassing, a problem in reliability (lifetime) remains particularly. In addition, since the plastic substrate has a difference in water absorption depending on the temperature, as the handling time in the air increases, the substrate temperature decreases, the amount of water absorption increases (the longer the longer the substrate is placed, the more it is saturated), and the vacuum degassing is performed. Will take longer. In particular, when the process proceeds from annealing to degassing to film formation via a hard coat process after molding, the time of leaving in the air becomes longer.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to produce a low-cost and more reliable disk by shortening the vacuum degassing time and, consequently, the process time by utilizing the effect of substrate annealing. And

[0005]

According to the present invention, a substrate holder, a mask, and a magazine placed around a substrate in a degassing chamber together with the substrate are simultaneously or separately provided with the substrate when the substrate is transferred from the annealing to the vacuum degassing step. Is carried out, and is sent into a degassing chamber while maintaining a high temperature state.

At the time of annealing, the substrate may be left attached to the holder, and the mask may be left attached. However, if both can be quickly assembled at a high temperature, the annealing may be performed separately.

When the substrate holder is large, it is also effective to anneal only the part to which the substrate is directly attached together with the substrate, and then attach the substrate to a large holder.

Further, when the substrate is sent together with the magazine to the vacuum degassing chamber, taken out of the magazine in a vacuum atmosphere and sent to the sputtering chamber, it is effective to anneal the entire magazine.

In addition, if the substrate holder is mounted on a tray, the tray is annealed together and sent to a degassing chamber. Also, if the substrate holder can be assembled and removed from the tray, after annealing the substrate and holder, assemble them into the tray, and then install them in the degas chamber or after annealing the substrate and holder separately, then assemble them all. Send to degas chamber.

[0010]

FIG. 4 shows a tray of a passing type sputtering apparatus, and FIG. 5 shows a self-revolving type tray. Normally, annealed substrates are set on these trays and sent to a vacuum degassing chamber. However, in the present invention, annealing is performed after setting the substrates on the trays, and the substrates are sent to the degassing chamber at a high temperature. Further, as shown in the example of FIG. 1, a configuration may be adopted in which a holder having a size similar to that of the substrate can be attached to the large tray (see FIG. 2), and only the holder may be annealed. FIG. 3 shows the exhaust characteristics when exhaust is performed by this method. FIG. 3 shows the initial 30 minutes as the vacuum degassing time.
Although it was necessary to perform degassing for a long period of time, a highly reliable disk could be obtained within one hour.
The annealing temperature is 90 ° C. and the annealing time is 1.5 hours.

[0011]

According to the present invention, (1) the tact time can be increased and the cost can be reduced by shortening the process time. (2) Since the temperature of the holder as well as the substrate is high, when the substrate is taken out into the atmosphere, no sharp temperature change is applied to the substrate, so that the distortion is small.

[Brief description of the drawings]

FIG. 1 is a side sectional view of a substrate holder having the same size as a substrate.

FIG. 2 is a side sectional view of a tray to which the substrate holder of FIG. 1 is attached.

FIG. 3 is a diagram showing exhaust characteristics of a substrate and the like.

FIG. 4 is a plan view of a tray of the pass-through type sputtering apparatus.

FIG. 5 is a plan view of a self-revolving tray.

[Explanation of symbols]

1, 10 tray 2 disk (or substrate) 3 substrate holder 4 inner mask 5 outer mask 6 tray 7 circular base 8 convex portion A Curve showing exhaust characteristics when only the substrate is annealed. B Curve showing the exhaust characteristics when the substrate is annealed together with the substrate holder.

Claims (4)

(57) [Claims] 1. A method for manufacturing an optical information recording medium, comprising: annealing a plastic substrate in the air, performing vacuum degassing, and then forming a recording layer by a vacuum thin film forming process.
A method for manufacturing an optical information recording medium, wherein a substrate and a substrate holder are simultaneously annealed during annealing in air. 2. A method for manufacturing an optical information recording medium, comprising: annealing a plastic substrate in the air and performing vacuum degassing, and then forming a recording layer by a vacuum thin film forming process.
A method for manufacturing an optical information recording medium, comprising annealing a substrate and a substrate holder separately during annealing in the atmosphere, setting the substrate in the holder in a high temperature state, and sending the substrate to a degassing chamber. 3. A method for manufacturing an optical information recording medium, comprising: annealing a plastic substrate in the air and performing vacuum degassing, and then forming a recording layer by a vacuum thin film forming process.
A method for producing an optical information recording medium, comprising: annealing a substrate in a magazine during annealing in the atmosphere, and sending the substrate to a vacuum degassing step together with the magazine. 4. The method for manufacturing an optical information recording medium according to claim 1, wherein the mask is also annealed at the same time.