JPH0230786A - Method for duplicating stamper - Google Patents

Abstract

PURPOSE:To obtain a high-quality duplicate stamper at low cost by forming a Cr layer, an Ag layer and a mold release processing film in order thereof on a glass master fitted with a photoresist and thereafter plating Ni by electroforming and peeling this electroformed Ni layer and renewing the Ag layer. CONSTITUTION:A glass master fitted with a photoresist wherein pits and grooves are formed is obtained by forming the photoresist layer 2 on a glass master disk 1. In this case, one part or the whole surface of the photoresist is removed in the inner face and the outside of a recording part wherein the pits and the grooves are formed. Then a Cr thin film layer 3 and an Ag thin film layer 4 are formed in order on the surface thereof by a vapor deposition method, etc. After a mold release processing film is formed on the Ag thin film layer 4, Ni is electroformed at prescribed thickness. Thereafter a first duplicate stamper is obtained by peeling this electroformed Ni layer 5. Furthermore the Ag thin film layer 4 on the glass master is removed and the Ag thin film layer 4 is newly formed on the Cr thin film layer 3 remaining on the glass master disk 1 and the electroformed Ni layer 5 is provided thereon to obtain a second and ensuing duplicate stampers.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a method for duplicating an optical memory standby.

[Conventional technology]

The conventional method for duplicating an optical memory standby is to first manufacture a crow master.

A mirror-polished glass master disk 1 with an outer diameter of 200 mm, an inner diameter of 101 fl, and a thickness of 6 mm is prepared.

] Before coating photoresist on the two-layer lath master 1, I
(The glass master 1 is exposed to MDS (hexamethylene disilazane) vapor, and the surface of the glass master is subjected to Si coupling treatment. The purpose of this Si coupling treatment is to bond the photoresist film 2 and the glass surface in the next step. Next, coat the photoresist to the expected thickness using a spin method, which is a 9th layer to improve adhesion.

Next, using a dedicated laser powering M/C, laser light is irradiated onto the pits and grooves of the processing position and shape for exposure.

Next, by chemically dissolving the exposed portion using a processing developer, a glass master in which pits and grooves are formed with photoresist on the glass master disk 1 is obtained.

Next, the Ni metal thin I required for Ni electroforming.
Form I6. The Ni thin film is generally formed by vapor deposition or sputtering. Appropriate thickness is about 1000A.

Next, Ni plating is performed to form a Ni electroformed layer 5 having a thickness of 300 μm.

Next, the Ni-electronic 8 layer 5 is peeled off from the glass master 1, the resist layer adhering to the Ni-electronic ON 5 is chemically dissolved, washed and dried, and the Ni-electroformed Ni-electroformed film has the pits and grooves formed on the glass master transferred thereto. Layer 5 is created. This Ni electroformed layer 5 is generally called a father.

In addition, when the glass master was used to make the above father, when the glass master and the Ni-electronic n layer 5 were removed, the point I was removed.
・Resist J? 42 is not completely destroyed by the Karasu Master side, so the appearance will be spoiled before it is removed, and it is not of a quality that can be used once.

Next, - after immersing the father in a chromic acid aqueous solution to form a release treatment film, Ni electroforming plating is performed to a thickness of 3
A Ni electroformed layer 5 of 00 μm size is formed.

Next, the Ni electroformed layer 5 formed through the father and the release treatment film is peeled off, thereby completing the Ni electroformed layer 5 on which the pits and grooves formed on the father have been transferred. This Ni electroformed layer 5 is called the mother.

Next, the mother is immersed in a chromic acid aqueous solution to form a release treatment film, and then Ni electroforming plating is performed to form a Ni electroforming layer 5 with a thickness of about 300 μm.

Next, Ni formed through the mother and template treated film.
When the electroformed layer 5 is peeled off, a Ni electroformed layer 5 is formed to which the pits and grooves formed in the mother are transferred. This Nign layer 5 is generally called a child and becomes a stamper used in actual molding.

As described above, the conventional stamper duplication method requires Ni electroforming plating at least three times to complete a duplicate stamper.

[Problem to be solved by the invention]

The conventional method of reproduction described above is to first make a father from a glass master, make a mother from a father,
The process of creating a child from a mother is performed three times to create a duplicate, which takes a lot of man-hours.

Furthermore, since the number of copies is large, it is easily affected by quality deterioration due to transfer.

An object of the present invention is to reduce the number of times of duplication and to provide a low-cost, high-quality duplication standber.

[Means to solve the problem]

The method for replicating a stamper of the present invention involves forming a gold thin film layer in the order of Cr and Ag on a glass master with a photoresist on which pits and croup are formed, and forming a release treatment film by immersing it in an aqueous chromic acid solution. Ni electroforming plating is applied to the thickness,
The first replicated standber is created by peeling off the template treatment film on the Ag thin film from the interface with the Ni electrolyte layer, and for the second and subsequent replicated standbars, the Ag thin film layer of the above-mentioned crow master is removed after each replication, and a new one is created. It is characterized by forming an Ag thin film layer on the surface and electroforming it with Ni.

〔Example〕

9A with outer diameter φ200 +u+, inner diameter φ10, thickness 6
Then, a polished glass master disk 1 is prepared.

Above, before coating the crow master 1 with photoresist
The glass master 1 is exposed to MDS (hexamethylene disilane) vapor, and the surface of the glass master is subjected to Si coupling treatment.

The purpose of this Si coupling treatment is to improve the adhesion between the photoresist film 2 and the glass surface in the next step.

Next, coat the photoresist to the treatment thickness using a spin method.

Next, the pit and groove portions of the processing position and shape are irradiated with laser light and exposed using a dedicated laser power cutting M/C.

Apart from the above exposure using the laser M/C,
The inside and outside of the recording section are irradiated with ultraviolet light and exposed.

Exposure of the inner and outer parts is very simple because the entire surface is exposed using a mask that prevents light from hitting the recording part.

Next, by chemically dissolving the exposed portion using a developing process, a glass master in which pits and grooves are formed with photoresist is formed on the glass master.

1. In the glass master, the photoresist is removed from the inside and outside of the recording area where pits and grooves are formed.

The purpose of removing the photoresist on the inside and outside of the recording area is to form an electroformed layer on the glass master in a later process and apply a Ni electroforming layer because the adhesion between the glass master and the photoresist layer 2 is not perfect. The purpose is to prevent the photoresist layer from peeling off when scraping from the glass master.

Next, thin films of Cr--Ag are formed on the entire surface of the glass master in this order. The method for forming the metal thin film is preferably a dry method such as a vapor deposition method or a sputtering method.

The thickness of Cr and Ag is preferably in the range of 100 to 500, respectively, and the total thickness is preferably 1000 Å or less.

The purpose of forming the Cr thin film layer 3 is to prevent the photoresist layer 2 from peeling off from the glass master.

That is, the adhesion between the photoresist layer 2 and the glass master 1 is not perfect even after the Si coupling treatment, and the Ni electrospinning in the next step causes the Ni heavy electric 9J resist to adhere to the glass master.

When the Cr thin film layer 3 is formed, since Cr has very good adhesion to the glass, the glass and Cr are completely adhered to the outside and inside of the pits and grooves where the resist was removed and the recording area. The purpose of forming the Ag thin film next to the Cr is that the photoresist film covered with the Cr thin film layer 3 is on the glass surface. is the underlying Cr thin film layer 3
This is because the Ag thin film layer can be easily removed without soaking the underlying Cr thin film layer due to chemical and metallurgical incompatibility with the Ag thin film layer.

Next, a peeling film is formed on the Ag thin film.

For forming the release treatment film, a commonly used method of immersion in an aqueous chromium solution can be adopted. Chromic acid compounds that can be used include chromic acid (cr2o,), sodium dichromate,
Potassium dichromate, ammonium dichromate, etc. The concentration may be 0.1% or less, the immersion time may be within 60 seconds, and the liquid temperature may be room temperature.

After forming the release treatment film, it is thoroughly washed with water and the first Ni8 plating is performed. 11 is a thickness of 300μ that can be used with a stamper.
Resting position is common. Ni electroforming plating baths are 0-order Ni sulfamic acid baths, which are generally used, and Ni? ? i
When the i-layer 5 is peeled off from the interface of the release treatment film of the Ag thin layer 4 of the glass master, a Ni electrolyte layer is formed in which the pits and grooves of the glass master are completely transferred.

By processing the inner and outer diameters of this Ni electroformed layer 5 and polishing the release surface, the first stamper made of a is completed. The glass master removed from the first duplicate stamper is used to manufacture the second and subsequent duplicate stampers. The L glass master contains Cr in the pits and grooves of the recording area, and in the areas where the glass is in contact with the Cr thin film layer 3 on the inside and outside of the recording area.
Since the thin film layer 3 and the glass are firmly adhered, the photoresist film 2 sandwiched between the glass and the Cr thin film layer 3 is not peeled off from the glass interface and the Cr thin film layer 3 interface. In this way, the glass master 1 is well adhered to the photoresist 1 to debris 2 and Cr thin rtA layer 3 formed on the glass master, so even if the same glass master is repeatedly duplicated, the photoresist will not peel off from the glass master. There are no appearance defects such as scratches.

A method for manufacturing the second and subsequent copy stampers will be described below.

First, the Ag thin film layer 4 of the glass master peeled off from the first copy stamper is removed. When removing the Ag thin film layer 4, it is important not to soak the underlying Cr thin film layer 3. As a material that does not meet the above requirements, a hydrogen peroxide-ammonia based Ag etching solution can be used. A
g Etch the thin film layer, rinse thoroughly with water, dry, and then re-apply Ag.
Form a thin film layer. The method for forming the metal thin film is preferably a dry method using a vapor deposition method or a sputtering method.

Next, the formation of a 6M-type treated film, which forms a release film on the Ag thin film, is carried out by dipping it in a chromic acid aqueous solution, which is a commonly used method. The appropriate thickness of the Ni electroformed layer to be electroplated is about 300 μm, which is the thickness that can be used in a stamper.

Next, when the Ni electroformed layer 5 is peeled off from the interface of the release treatment film of the Ag thin film layer 4 of the glass master, a Ni electroformed layer 5 in which the pits and grooves of the glass master are completely transferred is obtained.

By processing the inner and outer diameters of this Ni electroformed layer 5 and polishing the release surface, a second duplicate stamper is completed. The third and subsequent copies of the stamper are made repeatedly in the same manner as the second stamp.

The purpose of removing the Ag thin film layer 3 and forming a new Ag thin film layer 3 to make the second and subsequent duplicate stampers is to obtain a stamper with the same quality as the first duplicate stamper as much as possible.

Error rate is an important quality characteristic of a replica stamper.

The error rate is mainly determined by the appearance quality of the stamper.

The error rate becomes progressively worse as the number of replications increases.

This is because the Ni electroforming layer 5 is peeled off through the template treatment film that has been repaired to the matrix, but when it is peeled off, a part of the release treatment film follows the Ni electroforming layer. .

In conventional duplication methods, the same number of duplications must be made at least three times, and the appearance quality deteriorates with each duplication, resulting in a worsening of the error rate.

In the case of an optical memory stamper, a high error rate is required, and it is necessary to improve the level by nearly two orders of magnitude compared to a CD, and the conventional duplication method requires a large number of duplications, so it cannot be put to practical use. I just can't get anything on that level.

In the method according to the present invention, Ag
Since the thin Wi8 scraps 4 and the release treatment film are newly formed, the appearance quality level is almost the same as that of the first sheet, and the number of duplications is 1. By using two times, it is possible to obtain a stamper with stable appearance quality and high error rate.

〔Effect of the invention〕

As described above, the method for replicating a stamper of the present invention involves forming a thin film of Cr and Ag IIn on a photoresist-coated glass master in which pits and grooves are formed, and then immersing it in a chromic acid aqueous solution to form a release treatment film. Electroplated with Ni to the thickness of post-treatment, Ag1vI? ! The first replica stamper is made by peeling from the interface between the release treatment film on J 4 and the Ni electroforming layer 5, and the Ag thin film layer 4 of the glass master is removed for each replication for the second and subsequent replica stampers. , by forming a new Ag thin film layer 4 and performing Ni electroforming, one Ni
@It is possible to make a duplicate stamper in the casting process, and the conventional method requires at least 3 identical Ni electrodes. It becomes possible to provide a duplicate stamper at a lower cost than a duplicate stamper that requires a J plating process.

In addition, in terms of quality, the number of replications is small, and each time the Ag thin film (fJ 4) is removed and a new Ag thin film layer 4 is formed, the appearance quality is superior to that of conventional replication stampers. High quality products can be obtained.

[Brief explanation of the drawing]

FIGS. 1(a) to (g) are process sectional views showing the manufacturing process of the stamper duplication method of the present invention, and FIGS. 2(a) to (g)
) is a process sectional view showing the manufacturing process of a conventional stamper duplication method. Applicant Seiko Epson Co., Ltd. Agent Patent Attorney Kizobe Suzuki (and 1 other person) (d) ;==ear[=;Core 5 Figure 2

Claims (1)

[Claims] 1) A metal thin film layer is formed in the order of Cr and Ag on a photoresist-coated glass master in which pits and grooves are formed,
After forming a release treatment film by immersing it in a chromic acid aqueous solution, Ni is electroplated to the desired thickness, and the first sheet is peeled off from the interface between the release treatment film on the Ag thin film layer and the Ni electroforming layer. A method for duplicating a stamper, characterized in that a duplicate stamper is made, and for the second and subsequent duplicate stampers, the Ag thin film layer of the glass master is removed for each duplication, a new Ag thin film layer is formed, and Ni electroforming is performed. . 2) The method for replicating a standby according to claim 1, characterized in that the glass master with photoresist does not have photoresist partially or entirely formed on the inside and outside of the recording area in which pits and grooves are formed.