JP2995755B2 - Manufacturing method of stamper - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a stamper for an optical disk, and more particularly to a method for manufacturing a work stamper for manufacturing a glass substrate for an optical disk using a sol-gel method.

[Conventional technology]

A manufacturing process of a glass substrate for an optical disk using a conventional sol-gel method will be described.

First, master writing is performed on a glass master based on desired data. Next, a Ni stamper (master) is formed by subjecting the glass master to Ni sputtering and electroforming. Next, the Ni stamper (master) is used as a mold and electroforming is performed again to create a Ni stamper (mother). Using the Ni stamper (mother) thus prepared, a resin stamper for sol-gel is obtained by injection molding or 2P molding.

Next, an alcohol solution (sol-gel solution) containing metal alcoholate, polyethylene glycol, and hydrochloric acid is applied to the glass substrate by spin coating to form a sol-gel layer. The work stamper is pressed against the sol-gel surface to transfer a fine pattern. After the primary firing while being superposed, the glass substrate with the fine pattern released from the work stamper is further secondary fired. Through such a process, a glass substrate for an optical disk has been manufactured.

[Problems to be solved by the invention]

As described above, manufacturing a sol-gel work stamper currently requires a considerable process. This is because a Ni stamper (master) cannot be used directly as a work stamper for sol-gel. That is, if the primary firing is performed while the sol-gel layer and the Ni stamper are in close contact with each other, a part of the sol-gel layer adheres to the Ni stamper surface during mold release, and accurate pattern transfer cannot be performed.

For this reason, although the long process as described above is adopted, in particular, since a fine pattern is transferred many times over a relatively large area, there is a problem in terms of yield and cost.

The present invention provides an easy stamper manufacturing method capable of manufacturing a sol-gel work stamper directly from a glass master by so-called 2P molding.

[Means for solving the problem]

The method for manufacturing a stamper according to the present invention includes a step of applying a resist on a glass master, a step of exposing a desired pattern using a laser beam, a developing step of forming a resist layer having a fine pattern, Etching the glass master using the layer as a mask, removing the remaining resist layer, pressing a light-transmitting substrate against the glass master having a fine pattern, and curing the ultraviolet light between the glass master and the light-transmitting substrate. A step of filling with a resin, a step of irradiating ultraviolet rays through the light-transmitting substrate, and a step of releasing the light-transmitting substrate provided with an ultraviolet-curable resin layer having fine irregularities from the glass master.

Example First, a photoresist is applied to a glass master polished to a mirror surface by a spin coating method at 1000 to 3000 °. Next, laser beam exposure is performed by a master writer, and development is performed using a dedicated developer. Then, a photoresist as a mask, to etch the glass master by reactive ion etching using a gas such as CF _4. After that, the resist layer is removed using an ashing device. In this way, a glass master having a fine pattern can be manufactured.

An ultraviolet curable resin is discharged in a ring shape on the glass master using a dispenser. Next, the translucent epoxy substrate is pressed against the glass master so that the ultraviolet curable resin spreads sufficiently between the epoxy substrate and the glass master. Thereafter, UV irradiation is performed from the epoxy substrate side to cure the ultraviolet curable resin. By releasing the cured ultraviolet curable resin layer from the glass master, an ultraviolet curable resin layer having fine irregularities can be formed on the epoxy substrate. Thus, a sol-gel work stamper can be manufactured.

Next, a method for manufacturing a glass substrate using a sol-gel method will be described.

An ethyl alcohol solution containing tetraethoxysilane, polyethylene glycol, and hydrochloric acid was applied on a glass substrate by spin coating to form a sol-gel layer in a thickness of 2000 to 3000 Å. Next, the work stampers are overlapped and pressed under reduced pressure. In that state, primary calcination was performed at 100 ° C. for 10 minutes. Thereafter, the glass substrate was released from the work stamper and subjected to secondary firing at 350 ° C. for 10 minutes to obtain a glass substrate having a desired fine pattern.

〔The invention's effect〕

As described above, the method of manufacturing a stamper according to the present invention requires less steps than the conventional method, and does not require the use of a Ni stamper as a sol-gel stamper, so that the sol-gel layer adheres to the stamper. Disappears,
Its industrial significance is great.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G11B 7/26

Claims (1)

(57) [Claims] A step of applying a resist on a glass master;
Exposing a desired pattern using a laser beam, developing a resist layer having a fine pattern, etching a glass master using the remaining resist layer as a mask, and removing the remaining resist layer Pressing a translucent substrate against the glass master having a fine pattern, filling an ultraviolet curable resin between the glass master and the translucent substrate, irradiating ultraviolet rays through the translucent substrate, A method for manufacturing a stamper, comprising a step of releasing the translucent substrate provided with an ultraviolet curable resin layer having fine irregularities from a glass master.