JPH01277347A - Production of stamper - Google Patents

Abstract

PURPOSE:To remove the invasion of an abrasive or the like into a recording face side without extruding the trace of a current supply jig into an electroforming film and interrupting grinding work by setting up the surface of the current supply jig connected to a conductive film to the same level or lower as/than the surface of the conductive film. CONSTITUTION:The ring-like current supply jig 21 is fixed on an edge part 12 formed as an inclined part of a glass substrate 10 on which the conductive film 20 is formed and the electroforming film 30 is deposited on the surface of the conductive film 20 by using the film 20 as a cathode. Since the surface of the current supply jig 21 is set up to the same level or lower as/than the surface of the film 20, the trace of the jig 21 is prevented from being projected from the film 30. After depositing the film 30 with a prescribed thickness, the surface side of the film 30, i.e., the rear face side of a recording plane, is smoothly ground by a grinding device in the stuck state of the film 30 to the substrate 10. After ending the grinding work, both the films 20, 30 are peeled from the substrate 10 to form a stamper. Consequently, the interruption of the grinding work due to the trace of the current supply jig 21 or the invasion of the abrasive or the like into the recording side can be removed.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a method for manufacturing a stamper used for manufacturing optical disks, optical cards, or other optical application plastic products.

<Prior Art> Optical disks and the like have fine shapes on which information is recorded formed on their surfaces. Transfer molding of this fine shape is performed using a mold called a stamper.

FIG. 4 is a process diagram of a conventional stamper manufacturing method. Incidentally, for the sake of explanation, the thicknesses of the conductive film 20 and the electroformed film 30 in FIG. 4 are shown to be larger than the thickness of the glass substrate IO.

A photoresist 11 is uniformly coated on the smooth surface of a circular glass substrate 10 as a master material (see FIG. 4(a)), and cutting corresponding to the fine shape 111 is performed by irradiating laser light or the like (see FIG. 4(a)). (See Figure 4G).

The cut photoresist 11 is developed (see FIG. 3(C)), and a conductive film 20 is formed on the surface of the photoresist 11 (see FIG. 4(d)).

That is, the conductive film 20 is formed corresponding to the fine shape 111. This conductive film 20 is formed, for example, by sputtering or vapor depositing a conductive metal such as nickel.

A ring-shaped energizing jig 21 is connected to the edge 12 of the glass substrate 10, and the conductive film 20 is used as a cathode.
An electroformed film 30 is deposited on 0 by electroforming (Fig. 4 (
(see e)).

Thereafter, the back side of the recording surface of the electroformed film 30 is polished smooth using a polishing device or the like (not shown), and the stamper 40 is obtained after performing internal and external diameter processing, cleaning, and the like.

Note that in order to prevent damage to the recording surface during processing of the inner and outer diameters, the recording surface is coated with a resin that protects the fine features 111, and the resin is removed by cleaning.

The polishing process of the electroformed film 30 is performed by polishing the electroformed film 30 on the glass substrate 10.
There are two main methods: a method in which the electroformed film 30 is removed from the glass substrate 10, and a method in which the electroformed film 30 is left attached to the glass substrate 10.

<Problems to be Solved by the Invention> However, in the method of performing polishing after peeling the electroformed film 30 from the glass substrate 10, it is difficult to prevent the electroformed film 30 from warping due to internal stress of the electroformed film 30. Holders, reinforcing plates, etc. must be used, and extremely advanced technology and skill are required. In addition, the holders and reinforcing plates can be made using electroformed film 3.
Requires special equipment to attach to 0.

Furthermore, in the method of polishing the glass substrate 10 with the electroformed film 30 still attached, the electroformed film 30 is also deposited on the energizing jig 21 as shown in FIG. Trace 3
1 becomes a convex state. This energizing jig trace 31 becomes an obstacle during polishing. In addition, since the polishing surface is very close to the boundary between the glass substrate 10 and the electroformed film 30, abrasives and other foreign substances may enter the recording surface side from the current-carrying jig marks 31 during polishing. There is a problem in that the fine features 111 on the recording surface are damaged.

The present invention was devised in view of the above-mentioned circumstances, and aims to provide a method for manufacturing a stamper in which the marks of the energizing jig do not become an obstacle to the polishing process and the abrasives etc. do not enter the recording surface side. The purpose is

Means for Solving the Problems> The method for manufacturing a stamper according to the present invention includes making the surface of an energizing jig conductive, which is connected to a conductive film formed as an electrode on the surface of a glass substrate on which a fine shape is formed. It is characterized by being flush with or below the surface of the membrane.

Effects> A photoresist is coated on the surface of a substantially circular glass substrate by, for example, a spin-on coating method so as to have a uniform thickness, and prebatering is performed.

Cutting is performed by irradiating the photoresist with a laser beam or the like. Note that cutting here refers to forming a fine shape on the photoresist corresponding to the information to be recorded. That is, the laser beam is modulated by the information.

Develop the cut photoresist. The photoresist is now cured while retaining the fine shape corresponding to the signal to be recorded.

A conductive film is formed on the surface of the hardened photoresist.

Next, a ring-shaped electrification jig is attached to the edge formed as a slope of the glass substrate on which the conductive film is formed, and an electroformed film is deposited on the conductive film using the conductive film as a cathode.

At this time, since the surface of the energizing jig is on the same level as or below the surface of the conductive film, the traces of the energizing jig do not become convex with respect to the electroformed film.

Once the electroformed film has been deposited to a predetermined thickness, the front side of the electroformed film, that is, the back side of the recording surface, is polished smooth using a polishing device while the electroformed film remains attached to the glass substrate.

When the polishing process is completed, the conductive film and the electroformed film are peeled off from the glass substrate to form a stamper.

<Example> Hereinafter, an example according to the present invention will be described with reference to the drawings.

Fig. 1 is a cross-sectional view showing the edge of a glass substrate used in the stamper manufacturing method according to the present invention, and Fig. 2 shows a state in which an electrification jig is attached to the glass substrate and an electroformed film is deposited. FIG. 3 is a process diagram of a method for manufacturing a stamper according to the present invention. Incidentally, for the sake of explanation, the thicknesses of the conductive film 20 and the electroformed film 30 in FIG. 3 are shown to be larger than the thickness of the glass substrate 10. In addition, the same reference numerals are given to the parts, parts, etc. that are different from those of the conventional one in the explanation.

The glass substrate 10 as a master used in the stamper manufacturing method according to the present invention has a smooth surface,
In addition, the edge portion 12 is formed as a step or an inclined portion. In FIG. 1(a), the edge 12 is formed as a step, in FIG. 1(b), the step has an inclined part and a flat part, and in FIG. 1(C), the edge 12 is formed as an inclined part. FIG. 1(d) shows one in which the edge 12 is rounded. Although any of these four glass substrates 10 can be used, the effect of the gap will be exhibited, but in the following description, it is assumed that the stamper 40 is manufactured using the glass substrate IO shown in FIG. 1(C).

Next, a method for manufacturing the stamper 40 according to the present invention will be explained.

A photoresist 11 is coated on the surface of the substantially circular glass substrate 10 by, for example, spin-on coating so that the thickness is uniform (see FIG. 3(a)), and prebaked.

Photoresist 11 uniformly coated on glass substrate 10
Cutting is performed by irradiating the area with laser light or the like (see FIG. 3(b)). Note that cutting here means cutting a fine shape 111 corresponding to the information to be recorded onto the photoresist 11.
It refers to the formation of That is, the laser light is modulated by the information.

The cut photoresist 11 is developed (see FIG. 3(C)). The photoresist 11 is now cured while retaining the fine shape 111 corresponding to the signal to be recorded.

A conductive film 20 is formed on the surface of the hardened photoresist 11 (see FIG. 3(b)). This conductive film 20 is formed along the fine shape 111 of the photoresist 11 by sputtering a conductive metal such as nickel.

Next, a ring-shaped energizing jig 21 is attached to the edge 12 formed as an inclined part of the glass substrate 10 on which the conductive film 20 is formed.
is attached, and the electroformed film 30 is deposited on the conductive film 20 using the conductive film 20 as a cathode (see FIG. 3(e)). At this time, as shown in FIG. Since the surface of 21 is below the surface of the conductive film 20, the energizing jig trace 31 does not protrude with respect to the electroformed film 30.

Once the electroformed film 30 has been deposited to a predetermined thickness, the electroformed film 30
While still attached to the glass substrate 10, the front side of the electroformed film 30, that is, the back side of the recording surface, is polished using a polishing device (not shown).
(See Figure 3). Therefore, unlike a method in which polishing is performed after peeling the electroformed film 30 from the glass substrate 10, equipment for correcting warping of the electroformed film 30 due to internal stress of the electroformed film 30 is not required.

After the polishing process is completed, the conductive film 20 and the electroformed film 30 are removed.
and is peeled off from the glass substrate 10 (see FIG. 3 (6)).
. The conductive film 20 and electroformed film 30 peeled off from the glass substrate 10 have a microscopic shape 111 as shown in FIG. It has become.

Further, in order to protect this fine shape 111, the fine shape is coated with resin, and in this state, the conductive film 20 and the electroformed film 30 are coated.
The stamper 40 is then processed by processing the inner and outer diameters and cleaning.

This stamper 40 is used to manufacture optical discs and the like. Since the fine shape 111 on the recording surface of the stamper 40 is the reverse of that shown in FIG. 3(C), the fine shape 111 on the recording surface of the manufactured optical disk etc. is the same as that shown in FIG. 3(C). becomes the same as

In the above embodiment, the glass substrate 1 shown in FIG.
Although the present invention is not limited to this, for example, the same effect can be achieved by using glass substrates 10 as shown in FIGS. 1(a), (b), and (a). be able to.

Furthermore, even if a glass substrate 10 similar to the conventional one is used, it is also possible to use the glass substrate 10 shown in FIG.
If the energizing jig 21 is attached to the glass substrate 10 as shown in b), the same effect can be achieved since the energizing jig trace 31 does not become convex.

<Effects of the Invention> The stamper manufacturing method according to the present invention connects the surface of an energizing jig connected to a conductive film formed as an electrode on the surface of a glass substrate on which a fine shape is formed with the surface of the conductive film. Since it is on the same surface or less than that, the traces of the energizing jig will not protrude into the electroformed film, so even if the electroformed film is polished while it is still attached to the glass substrate, the electroformed film can be polished. It will not be a hindrance in case.

Furthermore, since the boundary between the glass substrate and the electroformed film is separated from the polishing surface, foreign substances such as abrasives will not enter the recording surface side and damage the recording surface during polishing.

Therefore, a high-quality stamper with high flatness (uniform film thickness) can be manufactured.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view showing the edge of a glass substrate used in the stamper manufacturing method according to the present invention, and Fig. 2 shows a state in which an electrification jig is attached to the glass substrate and an electroformed film is deposited. 3 is a process diagram of the stamper manufacturing method according to the present invention, FIG. 4 is a process diagram of the conventional stamper manufacturing method, and FIG. 5 is a process diagram of the glass substrate used in the conventional stamper manufacturing method. FIG. 3 is a cross-sectional view showing a state in which an energizing jig is attached to the edge and an electroformed film is deposited. 10... Glass substrate, 111... Fine shape, 1
2... Edge, 20... Conductive film, 21... Current supply jig, 40... Stamper.

Claims (1)

[Claims] (1) The surface of the energizing jig connected to the conductive film formed as an electrode on the surface of the glass substrate on which a fine shape is formed is on the same level as or below the surface of the conductive film. A method for manufacturing a stamper.