JPH0336021A - High hard stamper and manufacture thereof - Google Patents

Abstract

PURPOSE:To make it possible to form a stamper having no warpage without adhering dusts to and impairing a signal face by a method wherein high hard thin film made of oxide ceramics, nitride ceramics and carbide ceramics or their complex compound of metal, the thermal expansion coefficient of which is nearly equal to that of the base of the stamper and the thermal conductivity of which is high, is formed on the signal face of the stamper and on its opposite face. CONSTITUTION:Since the requirements of high hard thin film 2 is to have thermal expansion coefficient, which is nearly equal to that of Ni constituting of the base 1 of a stamper, and high thermal conductivity, oxide ceramics, nitride ceramics and carbide ceramics or their complex compound of Al, Cr, Zr, Ta, W, Mg, Ti, Mn or Ni is used. The high hard thin film 2 having the thickness of several 100 - several 1,000Angstrom is foamed by spatter spraying or the like. In the following process, electrically conductive film is formed and, after that, Ni plating having the thickness of 0.2 - 0.5mm is formed. The formations of the high hard thin film and of the electrically conductive film are performed by vacuum film making method. Next, high hard thin film 3 having the same thickness is formed out of the same material by the same means as mentioned above. The base 1 of the stamper is so constructed as to be sandwiched in between high hard thin films 2 and 3.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a high hardness stamper for duplicating optical discs and a method for manufacturing the same.

[Conventional technology]

When duplicating an extremely large amount of optical discs, a stamper is used as a mold for duplication. This stamper is made from a master disc.

Master discs and stampers are generally made by the following method.

The information signal is recorded on the master disc using an optical signal method or a mechanical method. A large number of small holes (pits) corresponding to information signals are created on the master disc.The surface of the zero-order master disc has several hundred to several thousand kO.
Forms a silver coating. This is to make the surface conductive for the next electroplating. This silver I
- Electrodeposit Ni as a t-cathode. This Ni layer is peeled off to complete the first mold.

Next, a peeling process (badge-bazing process) is performed using VC, such as dipping in a dichromium late potash solution, and Ni electrodeposition is performed on the surface side. The second mold is then peeled off from the first mold. At this time, the surface of the first mold is coated with silver, and the surface of the second mold is coated with Ni.

Next, the second mold is subjected to a peeling treatment in the same manner as described above, Ni is electrodeposited on its surface, and the mold is peeled off from the second mold to complete a stand bar, which is the final replica mold. Various efforts have been made in the past to make standbars made in this way have excellent scratch resistance and a long life.

For example, Japanese Patent Laid-Open No. 58-158057 discloses a standby whose surface is reinforced using kt or Or nitrided EA, and Japanese Patent Laid-Open No. 57-64308 discloses
1 on the surface of the i-stander using the ion blating method.
Part 4 or 5 discloses a material in which a nitride, carbide, or oxide of an element in Group 5, or a composite thereof is formed as an adhesion material.

[Problem to be solved by the invention]

However, the technique disclosed in Japanese Patent Application Laid-Open No. 58-158057 has the drawback that the process is long.
The technology disclosed in Japanese Patent No. 7-64508 does not significantly increase the number of steps, but after the shape of the Ni star/bar is formed, a hard film is vacuum-deposited on the signal surface. This was a problem because it increased the chances of getting dirt or scratches on it. Also, since a different type of film is applied to the Ni base material, thermal stress caused by the coefficient of thermal expansion and stress during film formation may cause
There were problems such as the stand bar warping.

An object of the present invention is to obtain a standby without prolonging the process, without causing dust or scratches on the signal surface, and without causing scratches or scratches. A further object of the present invention is to provide a method for manufacturing this stanbar.

[Means to solve the problem]

The high-hardness stubber of the present invention is made of a metal oxide, nitride, or carbide ceramic, or a composite compound thereof, which has a high thermal conductivity and has a coefficient of thermal expansion close to that of the stanbar base on the signal surface and the opposite surface of the stanbar. A highly hard thin film is formed.

And the metals are At, Cr, Zr, 'l'a
, WlMg, Ti, Mn% Ni.

Further, it is effective to increase the degree of twisting of the high-d degree thin film from several hundred to several thousand.

The method for producing a high hardness standber of the present invention is to
A first step of forming a photoresist exposed and developed with a laser beam on a disk, a second step of forming a highly hard thin film of metal oxide, nitride or carbide on the photoresist; After the second step, conductive film and Ni#1
A fifth step of forming gold, a fourth step of forming a highly hard thin film of a metal oxide, value compound, or carbide on the back side of the standber after this fifth step, and a fourth step of forming a highly hard thin film of metal oxide, value compound, or carbide on the back side of the standber; It consists of a fifth step of peeling off the stand bar from the glass master.

And high hardness thin films and conductive films are true! It is effective to use the 2 precepts membrane method.

[Effect]

After forming a high-hardness material that will ultimately form the 4'f1 surface of the standby on the master disc on which the unevenness has been recorded, a conductive film and N
Since i-plating is applied, there is less chance of the signal surface becoming dirty or scratched compared to forming a highly hard thin film after removing the Ni smen.

Furthermore, since the same material as the signal surface is formed on the back surface of the Ni standber, the amount of warpage of the Ni space member can be reduced. Furthermore, when attaching to a mold for replica molding, this high hardness film serves to soften the effect that some foreign matter that gets caught on the back side deforms into the stand bar 1 and has on the signal surface.

〔Example〕

Embodiment 1 of the present invention will be described below with reference to the drawings.

FIG. 1 is a modeled sectional view showing one embodiment of the present invention, and 25th to 3rd are sectional views showing the steps of the 1-m manufacturing method.

1 is a stamper base such as N, 2 is a high hardness thin film formed on the signal side, 3 is a high hardness thin film formed on the back side, and 4 is a signal bit of the stamper.

As the highly hard thin film 2, ceramic materials such as metal oxides such as Az+Crt Zr+Ta+W, nitrides, and carbides are preferable.

Note that the high hardness thin film 2 is made of Ni that constitutes the stamper base 1.
In addition to AtI Cr I Zr ITa*W, MglTilMn+Ni oxides, nitrides, carbides, ceramic materials, or composite compounds thereof are also used. be able to.

These highly hard thin films 2i2 are densely formed to a thickness of several 100 to several 100 OA by a method such as ion blasting or sputtering.

Stampers are used as masters for plastic molds.
After being used thousands or tens of thousands of times, the part corresponding to bit 4 has become worn and scratched. Since the scratch resistance of the stamper depends on its hardness, it is effective to provide a hard layer on the surface as in this embodiment. In particular, sputtering is a suitable method because it can form a film with good jRb content even on the unevenness of the bit.

Next, a manufacturing method which is an embodiment of the present invention will be described along with the $2 diagram. FIG. 2(1) shows a state in which a photoresist 6 is formed on a master disk 5 made of glass or the like, which is exposed to a laser beam or the like and developed.

Reference numeral 7 indicates a signal bit. In the conventional method, a conductive film is then formed and the process moves to Ni plating, but in this embodiment, (2
) step, the highly hard thin film 2 of the above-mentioned material is formed to a thickness of several 100 to several 100 OA by a method such as sputtering.In the 0th step (3) step, a conductive film is formed (not shown in the figure) and pulled. Subsequently, Ni plating is formed (12 to (L5ma+).

The formation of the highly hard thin film and the conductive film are performed by a vacuum film forming method. In the zero-order K (4) process, in which backside polishing is performed as necessary to make the thickness of the stamper uniform, the high hardness thin film 5 is made to almost the same thickness using the same material and the same method as in the (2) process. It is formed. In the step (5), the stamper of this example is peeled off from the (glass) master 5, and the stamper base 1 has a structure in which the highly hard thin films 2 and 5 are sandwiched together.

According to this embodiment, even if the coefficient of thermal expansion of the high hardness thin film is slightly different from that of the stamper base 1, the film will not warp.
Furthermore, since the films are formed using the same method, the stress accumulated in the films can be considered to be approximately the same, resulting in a multilayered stamper with less warpage.

In addition, the formation of a highly hard film on the surface is facilitated when the film stress is small and the coefficient of thermal expansion of the thin film is close to that of the stamper substrate 1.
I can do things.

Furthermore, since the formation of the highly hard thin film and the formation of the conductive film are carried out by a vacuum film forming method, continuous molding can be performed, which has the advantage of reducing the chances of dust or scratches.

〔Effect of the invention〕

The high hardness thin film of the present invention is placed on the sandwich on the front and back sides.
i! With this structure, we were able to create a stamper with less scratching and significantly improved scratch resistance. Furthermore, by depositing the second high-hardness thin film before forming the conductive film, a manufacturing process with less dust and scratches can be achieved.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of a stamper showing an embodiment of the present invention, and FIG. 2 is a cross-sectional view showing the steps of the stamper manufacturing method of the present invention. 1... Stamper base, 2... High hardness thin film (front side) 5... High hardness thin film 2 (back side), 4.
... Stamper signal bit, 5 ... Glass master, 6 ... Photoresist, 7 ...
・Master signal bit.

Claims (1)

[Claims] 1. The stamper signal surface and its opposite surface are made of a metal oxide, nitride, or carbide ceramic or a composite compound thereof, which has a high thermal conductivity and has a coefficient of thermal expansion close to that of the stamper base. A high-hardness stamper characterized by forming a hard thin film. 2. The metals Al, Cr, Zr, Ta, W, Mg, Ti
, Mn, and Ni. The high-hardness stamper according to claim 1. 3. The high-hardness stamper according to claim 1 or 2, wherein the high-hardness thin film has a thickness of several hundred Å to several thousand Å. 4. A first step of forming a photoresist exposed and developed by a laser beam on a glass master disk, and a second step of forming a highly hard thin film of metal oxide, nitride, or carbide on the photoresist. After this second step, there is a third step of forming a conductive film and Ni plating, and after this third step, a highly hard thin film of metal oxide, nitride, or carbide is formed on the back surface of the stamper. A method for manufacturing a high-hardness stamper, comprising a fourth step and a fifth step of peeling off the stamper from the glass master after the fourth step. 5. The method for manufacturing a high-hardness stamper according to claim 1, wherein the high-hardness thin film and the conductive film are formed by a vacuum film forming method.