JP3103440B2 - How to store the stamper - 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 storing a stamper for an optical disk or the like.

[0002]

2. Description of the Related Art A conventional storage method of a stamper for an optical disk having signals such as address information and video / audio signals will be described with reference to FIG. A resin 8 containing a copolymer of vinyl chloride and vinyl acetate as a main component is applied to the surface of a stamper 1 for an optical disk (hereinafter, a stamper used for duplicating the stamper is referred to as an original stamper) 1 using a spinner 9. (FIG. 4A), this is used as a protective film 10 to prevent contamination of the optical disk stamper and protect the stamper (FIG. 4A).
(B)). When duplicating a stamper for an optical disk using the original stamper 1, the protective film 10 of the original stamper is peeled off (FIG. 4B), and the organic contaminant 11 adhered by the protective film is removed.
To clean the surface of the original stamper 1 (FIG. 4).
(C), (d)). Thereafter, a duplication operation (electroforming operation) of the optical disk stamper is performed (FIG. 4E).

[0003]

According to the conventional method of storing a stamper, the organic substance in the protective film remains as a thin film on the stamper for an optical disk. In an optical disk stamper used for molding a normal resin substrate, there is no problem even if an organic thin film remains, but in the case of an original stamper used for duplicating an optical disk stamper, if the organic thin film remains, During the electroplating, the original stamper and the duplication stamper (hereinafter, a stamper duplicated from the original stamper is referred to as a duplication stamper) may peel off, and duplication may not be possible.

Further, when a duplicate stamper is manufactured using an original stamper having contaminants left on the surface, the contaminants are transferred to the duplicate stamper as it is, resulting in a defect. For this reason, usually, in the copying operation, a cleaning process is performed before applying a release film to the stamper, and the surface of the original stamper is cleaned to make it a clean surface before the copying operation. However, even if the surface cleaning process is performed, it is difficult to make the surface of the original stamper a clean surface, and the surface cleaning process may easily cause re-contamination of the stamper surface. It is considered that this is because the surface cleaning treatment generates strong active sites on the surface of the stamper, and the strong adsorption action causes recontamination (mainly, organic substance contamination). On the other hand, even when the surface cleaning treatment is not performed, the surface contamination progresses as time passes, and some antifouling measures are required.

According to the present invention, a stamper having a clean and hardly re-contaminated surface, which can be used for duplicating a stamper for an optical disk with high transfer accuracy, can be obtained, and the process can be simplified. An object is to provide a method for storing a stamper.

[0006]

According to the present invention, the above object is achieved by a method for storing a stamper, which comprises irradiating the surface of the stamper with ultraviolet rays in an oxygen atmosphere.

[0007]

[Action] When ultraviolet rays are irradiated in an O ↓ 2 (oxygen) atmosphere, O ↓ 3 (ozone) is generated, which breaks molecular bonds of contaminating organic substances and becomes a state where it easily reacts with radical oxygen. This radical oxygen acts on the organic pollutants to convert the polluted organic substances into C.
Oxidatively decomposes into O, CO ↓ 2, H ↓ 2O, etc. According to the present invention, since the original stamper having a clean surface after performing a cleaning process such as an oxygen plasma cleaning process is irradiated with ultraviolet rays, adsorbed contaminants (mainly organic substances) can be reduced to CO, CO ↓
2. Oxidized and decomposed into H ↓ 2O, etc., so that a clean optical disk stamper surface can always be obtained. Further, even when the optical disk stamper is stored for a long period of time, there is no need to apply and store a protective film, and the organic matter in the protective film remains on the optical disk stamper as a thin film of the organic material, and there is no need to clean it. Therefore, the process can be simplified. Furthermore, since organic contaminants that cannot be removed by surface cleaning are decomposed during storage, a replica stamper with few defects can be manufactured.

[0008]

An embodiment of the present invention will be described with reference to FIG. An optical disk stamper (original stamper) 1 is prepared (FIG. 1).
(A)). The original stamper 1 has wavelengths of 185 nm and 254 nm.
1 is stored in a storage box 4 equipped with a low-pressure mercury lamp 2 capable of irradiating ultraviolet rays having two emission peaks (FIG. 1)
(B)). When the duplicating stamper 3 is manufactured, it is taken out of the storage box 4, washed with water, spin-dried (FIGS. 1 (c) and 1 (d)), and then a duplicating operation of the optical disk stamper is performed (FIG. 1 (e)). .

FIG. 2 shows a schematic configuration diagram of an example of the storage box 4 described above. In the storage box 4 shown in FIG.
Low pressure mercury lamps 2a to 2c capable of irradiating ultraviolet rays having two emission peaks of 85 nm and 254 nm can always be irradiated on the original stamper 1 in an O ↓ 2 (oxygen) atmosphere, and the surfaces of the original stampers 1a to 1c are generated. It is exposed to O ↓ 3 (ozone) and radicals. In this case, the stamper may be corroded by constantly irradiating the ultraviolet rays. In particular, when moisture is present in the storage box, the corrosion is promoted. Therefore, the moisture in the air in the storage box is controlled. It is preferable to provide a humidity control 5. Further, in order to prevent the original stamper 1 from being soiled by dust in the storage box 4, it is preferable to circulate clean air 7 through a filter 6 such as HEPA in the storage box 4. If an organic material is used as the material used for the storage box 4, the surface of the original stamper 1 may be stained. Therefore, it is preferable not to use the organic material.

FIG. 3 shows the relationship between the storage time when the stamper is stored according to the present invention and the contact angle of the stamper surface with pure water.
(A: one-dot chain line). In accordance with FIG. 3, the relationship between the storage time when the conventional cleaning treatment is applied to the stamper and the contact angle of the stamper surface with pure water (FIG. 3 (b: wavy line)) and the storage without the cleaning treatment The relationship between the time and the contact angle of the stamper surface with pure water (FIG. 3 (c: solid line)) is shown. It is clear from FIG. 3 that according to the present invention, contamination of the stamper surface is small.

The stamper to be stored in accordance with the present invention may be a stamper to be used for molding a substrate, other than a stamper to be used for duplication of the stamper. Has a remarkable effect.

[0012]

According to the present invention, it is possible to obtain a stamper which has a clean surface and has a surface on which re-contamination hardly proceeds, and which can be used for duplicating a stamper for an optical disk with high transfer accuracy. A method for storing a stamper that can be used is provided.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of an embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of an example of a storage box used in the present invention.

FIG. 3 is a diagram showing a relationship between a storage time of a stamper and a contact angle of the stamper surface with pure water.

FIG. 4 is an explanatory diagram of a conventional method of storing a stamper.

[Description of Signs] 1, 1a-1c Original stamper 2, 2a-2c Low-pressure mercury lamp 3 Duplicating stamper 4 Storage box 5 Humidity control 6 Filter 7 Clean air

Claims (1)

(57) [Claims] 1. A method for storing a stamper, comprising irradiating the surface of the stamper with ultraviolet rays in an oxygen atmosphere.