JPS63131351A - Stamper for information recording medium - Google Patents

Abstract

PURPOSE:To improve the durability and to reduce the manufacture cost and a manufacture time by forming a die base material made of a type of material having a larger heat conductivity than that of glass, and making a master material from a type of material offering easier mechanical processing than that of the glass and die base. CONSTITUTION:The master material 1 subjected to mechanical processing to mount on the compression jig and the die base material 2 having a slot pattern on its surface are bonded at each rear face via a bonding layer 3 inbetween. The die base material 2 is made of a material whose terminal conductivity is larger than that of glass and the master material 1 is made of a material offering easier mechanical processing than that of the glass and the die base material 2. Thus, the durability is improved more than that of a nickel plating the and the manufacturing cost and manufacturing time are reduced.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention relates to a stamper for information recording media that is used to provide unevenness such as guide grooves in the production of information recording media.
Regarding the configuration of

(Prior Art) Conventionally, stampers for information recording media have been typically manufactured as follows. That is, first, a pattern is formed on a photoresist film coated on a glass plate using a laser beam, and then nickel electroforming is usually repeated multiple times using this pattern as a prototype, thereby creating an electroforming mold with the pattern transferred thereon. It was manufactured as.

(Problems to be Solved by the Invention) However, such standbars for information recording media have low durability because of the limited materials that can be used and the difficulty in making them thick due to manufacturing methods. There were problems such as the amount of water required.

As a standber for information recording media manufactured by another manufacturing method, Japanese Patent Application Laid-Open No. 60-173738 discloses an A1. Cr, Fe, Ge, Mo, Nb, Sb,
Se, Ta, Te, Tl.

A stamper for an information recording medium is shown in which a pregrooved thin film made of the elements V, W, and oxides, nitrides, and halides of these elements is provided.

However, this stamper has the disadvantage that it cannot be easily processed to attach it to a compression molding jig, and has poor heat conduction. The disadvantages are that the temperature distribution becomes uneven and that heating and cooling takes a considerable amount of time.

An object of the present invention is to provide a standber for information recording media that eliminates the drawbacks of conventional nickel electroforming molds such as low durability, high cost, and long manufacturing time.Other objects of the present invention are , provides a stamper for information recording media which eliminates the drawback of conventional stampers using glass as a mold base material, namely, the difficulty of attaching the information recording media substrate to a molding jig, typified by a compression jig. It's about doing.

Still another object of the present invention is to improve the temperature distribution of the substrate material during molding of the substrate for information recording media by using a material with higher thermal conductivity than glass for the main part, and to reduce the heating and cooling required for the substrate material. An object of the present invention is to provide a standber for an information recording medium, which enables time reduction.

[Means for solving the problem] The above object is achieved by cutting grooves or by partially depositing a hard thin film.

Information formed by joining a mold base material with a pattern on its surface and a base material whose surface has been machined for attachment to a molding jig for an information recording medium substrate on their back surfaces. In the stand bar for recording media, the mold base material is made of a material with higher thermal conductivity than glass, and the base material is made of a material that is easier to machine than glass and the mold base material. This can be achieved by a standber for information recording media having the following characteristics.

The present invention will be explained in more detail below with reference to the drawings.

FIG. 1 is a schematic sectional view of one embodiment of the present invention. This stambar for information recording media consists of a base material 1 that has been machined for attachment to a compression jig, and a mold base material 2 that has a pattern of grooves on its surface, which are joined by a bonding layer 3 between them. It has a similar structure.

Base material 1 (The machining performed here is essentially determined according to the forming jig (compression forming jig here) of the information recording medium substrate to which this information recording medium stand bar is attached. For example, cutting for forming screw holes, end face cutting, chamfering, etc. are performed.

The base material 1 is selected from glass and a material that is easier to machine than the mold base material 2. For example, metals such as invar alloy,
Among ceramics such as fused alumina and glass ceramic, the material is suitable for the mold base material 2.

The material of the mold base material 2 is selected so that it meets the required durability, and in fact has higher durability than the nickel electroforming mold.
It was chosen because its thermal conductivity is greater than that of glass. A preferable material for the mold base material 2 has a thermal conductivity 2 to 4 times higher than that of glass.

Such selection of materials makes it possible to make the temperature distribution of the substrate material uniform during molding of the information recording medium substrate and to improve the heating and cooling speed.

Specific examples of the material of the mold base material 2 include a silicon single crystal substrate, a ceramic such as fused alumina, and a metal such as cemented carbide. Among these, a silicon single crystal substrate is preferred. Note that it is preferable to use a material for the mold base material 2 whose surface has a surface roughness of 100 Å or less, so a material that can provide such a surface roughness is used.

Grooves in the mold base material 2 are typically formed by a method that combines photolithography and etching techniques, that is, after forming a desired pattern on the surface of the mold base material with a photoresist layer, the exposed surface of the mold base material 2 is formed. It is provided by a dry etching method.

The raw material for the bonding layer 3 is appropriately selected depending on the mold base material 2 and base material used, but it is preferable to use a material that exhibits as strong a bonding force as possible.

Another embodiment of the present invention is shown in FIG. 2, and this standbar for information recording media includes a mold base material 2a having a surface roughness of 100 Å or less on which a hard thin film 4 constituting a pattern is formed, and a mold base material 2a for recording information. A base material 1 that has been machined for attachment to a forming jig for a media substrate is bonded by a bonding layer. The hard thin film 4 is made of Al, Cr, Mo, Nb, Si, T.
a, 1 selected from the group consisting of Ti, V, W, Zr, and oxides, nitrides, carbides, and borides of each of these elements;
It is made up of more than one seed, and not only forms the pattern, but also functions to supplement the surface hardness of the mold base material 2.

[Example] The stambar for information recording medium shown in FIG. 3 was formed as follows.

5 inch diagonal Invar alloy (thermal conductivity 2.6XIO)
-" (room temperature to 200°C)) was machined (screw holes, end face cutting, chamfering, etc.) for attachment to a compression jig, and the other side was mirror polished, which was used as base material 1. The surface of a 5-inch diagonal silicon single-crystal substrate was polished to a thickness of 100 Å or less, and a pattern was formed by carving a groove about 1000 deep on the surface through a photolithography process.This was called mold base material 2. On the mold base material 2, an At foil 3a, a W thin film 3b, and an Al-5i brazing material 3c (
These three layers were stacked together in the order of composite layer 3), and base material 1 was further placed on top of the composite layer 3). By treating this under the conditions shown in Figure 4 (i.e., heating it to 650°C in a vacuum atmosphere while applying a load of 500 to 9 so as not to damage the surface of the silicon single crystal substrate, and keeping it as it is for 60 minutes. The mold base material 2 and base material 1 were bonded together (by holding and then quenching with N2 gas) to form a stand bar for an information recording medium.

Although the process was carried out in an inert gas or reducing atmosphere instead of a vacuum atmosphere, a similar standber for information recording media was produced.

Example 2 Instead of the mold base material 2 of Example 1, A1. Cr, Mo, Nb, Si, Ta
, Ti.

A hard thin film 4 (maximum thickness: 5
A plurality of standbars for information recording media shown in FIG. 5 were manufactured in the same manner as in Example 1, except that a film having a thickness of 1,000 mm and a groove depth of 1,000 mm was used.

[Effects of the Invention] In the information recording medium stand bar of the present invention, a metal material (for example, invar alloy), fused alumina, and ceramic such as glass ceramic, which can be easily machined on the back surface, is used. As a result, there is no factor that makes it difficult to attach the information recording medium substrate to the molding jig, and it has become possible to eliminate the drawbacks of conventional stampers using glass for the substrate.

Moreover, the information recording medium standbar of the present invention uses a material whose thermal conductivity is higher than that of glass, especially a material whose thermal conductivity is two orders of magnitude higher (for example, a silicon crystal substrate, molten alumina, and a cemented carbide) for its main parts. Therefore, when molding a substrate for an information recording medium, it is possible to improve the temperature distribution of the material and increase the heating and cooling speed.

In addition, by appropriately selecting materials and manufacturing methods, the information recording medium standbar of the present invention can reduce manufacturing costs and manufacturing time compared to two-unit electroforming molds. In particular, when a silicon single crystal plate is used as the mold base material, a commercially available silicon wafer can be used as is, and normal wafer in-line can be used, so the manufacturing cost and manufacturing time can be significantly reduced compared to nickel electroforming molds.

[Brief explanation of the drawing]

1 and 2 are schematic cross-sectional views showing one embodiment of the scrubber for information recording media of the present invention, and FIGS. 3 and 5 are schematic cross-sectional views showing the scrubber for information recording media of the embodiment, respectively. 4
The figure is a diagram showing bonding temperature conditions in Examples. 1: e material 2.2a: mold base material 3: bonding layer

Claims (1)

[Claims] 1) A mold base material with a pattern provided on its surface by cutting grooves or partially forming a hard thin film, and a molding jig for an information recording medium substrate. A stamper for an information recording medium is formed by joining a base material whose surface has been machined for attachment to the stamper with their respective back surfaces, and the mold base material is made of a material with higher thermal conductivity than glass. A stamper for an information recording medium, characterized in that the base material is made of glass and a material that is easier to machine than the mold base material. 2) Claim 1, wherein the mold base material is cemented carbide, mold steel, silicon, fused alumina, or glass ceramic.
A stamper for information recording media as described in Section 1. 3) The hard thin film is made of Al, Cr, Mo, Nb, Si, T.
The information set forth in claim 1 or 2, consisting of one or more selected from the group consisting of a, Ti, V, W, Zr, and oxides, nitrides, carbides, and borides of each of these elements. Stamper for recording media. 4) The stamper for an information recording medium according to any one of claims 1 to 4, wherein the base material is made of an invar alloy, W, or Mo.