JPH0689471A - Production of optical information recording medium - Google Patents

Abstract

PURPOSE:To shorten vacuum degassing time, that is, to shorten process time and to obtain a high durable diskc by simultaneously annealing a substrate and a substrate holder at the time of annealing in the air. CONSTITUTION:When the substrate is sent from the annealing stage of substrate to a vacuum degassing stage, the substrate holder 3 placed at vicinity to the substrate 2 in the degassing chamber is annealed together with or separately from the substrate 2, and sent to the degassing chamber while keeping it at a high temp. At the time of annealing, the substrate 2 may be mounted as it is to the substrate holder 3, moreover, mask 4 and 5 may be mounted. But if both masks can be mounted quickly while being kept at a high temp., they may be annealed seperately.

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 The manufacturing process of a magneto-optical disk is generally a stamper → substrate formation → relaxation of stress in the substrate by annealing →
Vacuum degassing → film formation → cover layer coating is performed. Further, the hard coat layer coating step is usually incorporated before annealing or after film formation. A CD and a phase change disk are manufactured by almost the same process.

However, in such a process, since the substrate absorbs water after the substrate is formed, a problem remains particularly in reliability (lifetime) unless the vacuum degassing takes a long time to sufficiently perform dehydration. In addition, since the plastic substrate has different water absorption depending on the temperature, the substrate temperature decreases as the handling time in the atmosphere becomes longer, and the water absorption increases (the longer it is placed, the more it saturates), and the vacuum degassing occurs. Will take longer. In particular, when the process proceeds in the order of annealing → degassing → film formation through a hard coat process after molding, the time of standing in the air becomes longer.

[0004]

DISCLOSURE OF THE INVENTION The present invention aims to produce a more reliable disk at a low cost by utilizing the effect of substrate annealing and shortening the vacuum degassing time and eventually the process time. And

[0005]

According to the present invention, a substrate holder, a mask and a magazine, which are placed around a substrate in a degassing chamber together with the substrate, are simultaneously or separately provided with the substrate when the substrate is sent from the substrate annealing to the vacuum degassing step. It is characterized in that it is annealed and is fed into the degassing chamber while maintaining a high temperature.

At the time of annealing, the substrate may be attached to the holder or the mask may be attached. However, if both can be quickly assembled at high temperature, they may be annealed separately.

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

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

In addition, if the substrate holder is attached to the tray, the tray is annealed together and sent to the degassing chamber. If the substrate holder can be attached to and removed from the tray, anneal the substrate and holder and then assemble them to the tray and anneal them to the degassing chamber or anneal the substrate and holder separately and then assemble them all. Send to degassing chamber.

[0010]

EXAMPLE FIG. 4 shows a tray of a passage type sputtering apparatus, and FIG. 5 shows a rotation type tray. Usually, the annealed substrate is set on these trays and sent to the vacuum degassing chamber, but in the present invention, after being set on these trays, annealing is performed and the substrates are sent to the degassing chamber at a high temperature. Alternatively, as shown in the example of FIG. 1, a holder having the same size as the substrate can be attached to the large tray (see FIG. 2), and only the holder may be annealed. FIG. 3 shows the exhaust characteristic when exhausted by this method. Although FIG. 3 shows the initial vacuum degassing time of 30 minutes, it is actually 2
Although the gas had to be degassed for a time, a sufficiently 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 holder as well as the substrate has a high temperature, the substrate is not subject to a sudden temperature change when taken out into the atmosphere, so that the strain is small.

[Brief description of 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 a passage type sputtering device.

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

[Explanation of symbols]

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

Claims (5)

[Claims] 1. A method of manufacturing an optical information recording medium, comprising: forming a recording layer by a vacuum thin film forming process after annealing a plastic substrate in the atmosphere and performing vacuum degassing,
A method for manufacturing an optical information recording medium, characterized in that a substrate and a substrate holder are simultaneously annealed at the time of annealing in the atmosphere. 2. A method for manufacturing an optical information recording medium, which comprises forming a recording layer by a vacuum thin film forming process after annealing a plastic substrate in the air and performing vacuum degassing,
A method of manufacturing an optical information recording medium, characterized in that a substrate and a substrate holder are separately annealed during annealing in the air, and the substrate is set in the holder at a high temperature and sent to a degassing chamber. 3. A method for manufacturing an optical information recording medium, which comprises forming a recording layer by a vacuum thin film forming process after annealing a plastic substrate in the atmosphere and performing vacuum degassing.
A method for manufacturing an optical information recording medium, characterized in that the substrate is annealed in a magazine during annealing in the atmosphere and is sent to a vacuum degassing process together with the magazine. 4. The method of manufacturing an optical information recording medium according to claim 1, wherein the mask is also annealed at the same time. 5. A plurality of substrate holders, each of which is mounted on and detachable from the central portion and the outer peripheral portion, and is composed of a circular base having a convex portion to which the inner and outer peripheral substrate masks can be attached Substrate tray characterized by.