JPH04259938A - Production of stamper for producing information recording medium - Google Patents

Abstract

PURPOSE:To produce the stamper for producing information recording media with a smaller number of transfer times. CONSTITUTION:The thin film of a positive type photoresist stuck and formed on the thin film of a metal deposited on the specular surface-like surface of a silicon wafer for substrates or the silicon wafer is exposed with recording light and is developed. The recessed parts corresponding to the information signals to be recorded are formed by a dry etching method on the silicon wafer or the thin film of the metal with the thin film of the developed positive type photoresist mentioned above as a mask member. The remaining thin film 2 of the positive type photoresist is removed to obtain the matrix for producing the information recording media. The stamper for producing the stuck and formed by an electrocasting method on the matrix for producing the information recording media is peeled, by which the stamper for producing the information recording media is obtd.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a stamper for producing information recording media.

0002

[Background Art] Recesses (pits) corresponding to the information signal to be recorded and reproduced are formed on the signal surface, and the information signal is read by illuminating the signal surface with a light spot with a minute diameter. Such recorded information recording media have conventionally been put to practical use as compact discs, video discs, digital audio discs, recordable discs, and other optical discs. When mass producing the various types of recorded information recording media described above, a stamper for producing information recording media is used, the surface of which is formed with uneven portions corresponding to the information signals to be recorded and reproduced. This is done by transferring the uneven shape on the surface of the stamper for producing information recording media to the surface of the disk made of synthetic resin. , the surface unevenness of a recorded information recording medium is, of course, an opposite unevenness {the protrusions (or recesses) of one correspond to the recesses (or convexes) of the other The correspondence relationship between the concave and convex shapes is as follows.

By the way, the most common conventional manufacturing method for a stamper for manufacturing an information recording medium is to record information using a thin film of positive photoresist formed on a mirror-polished glass master disk. After being exposed to recording light whose intensity is modulated by a signal, it is developed, and after the development, electroforming is performed on the metal thin film formed by means such as electroless plating, and then peeled off to create a master disc. ,
After performing a peeling treatment on the master disk surface, electroforming is performed, and then it is peeled off from the master disk to obtain a mother disk,
Next, the production of a stamper for producing information recording media consists of various steps such as applying a peeling treatment to the mother disc surface, electroforming is performed, and then peeling it off from the mother disc to obtain a stamper for producing information recording media. It is the law.

0004

Problems to be Solved by the Invention Among the various types of disks whose surface irregularities are opposite to each other obtained in each successive process in the conventional manufacturing method of a stamper for manufacturing an information recording medium, Since the master disk and the stamper for producing information recording media have the same surface irregularities, it goes without saying that the master disk can also be used as a stamper for producing information recording media. However, although the above master disc is obtained by transferring a pattern of a thin film of photoresist, the thin film of photoresist on the glass master disc has low mechanical strength, so the photoresist is Because the thin film pattern is destroyed by a single transfer operation, it is not possible to create multiple master disks by performing multiple transfer operations on a photoresist thin film formed on a glass master disk. Therefore, unless it is sufficient to duplicate a small number of recorded information recording media, it is common practice not to use the master disc as a stamper for producing information recording media; As mentioned above, the stamper for production was made by electroforming twice after obtaining the master disk to obtain the stamper for production of information recording media. Stampers can also be easily obtained. However, when the conventional method described above requires a large number of transfers to obtain a stamper for producing an information recording medium, there are many chances that the recording signal waveform may be deformed or defects may occur due to adhesion of foreign matter. , there is a risk that the information recording medium will have deteriorated recording and reproducing characteristics.
Further, there are problems in that a large amount of electrical energy and pure water are consumed due to the electroforming being performed many times, and a large amount of time is required for manufacturing.

[0005] In order to solve the above-mentioned problems of the most common conventional method of manufacturing a stamper for manufacturing an information recording medium, a conventional method has been developed in which a stamper for manufacturing an information recording medium can be manufactured by only one transfer operation. As a method for producing a stamper for producing an information recording medium, ■ Using a thin metal film deposited on a glass substrate, dry etching or wet etching is performed on the metal thin film to form pits; Alternatively, a manufacturing method has been proposed in which the substrate itself is subjected to dry etching or wet etching to form pits. There is a problem that the stock is large and therefore requires a large space for the stock.In addition, in the conventionally proposed manufacturing method of (■), the surface roughness and flatness of the metal plate such as nickel, aluminum, and copper used as the substrate There is a problem in that it is not possible to obtain something that is completely satisfactory.

[0006]

[Means for Solving the Problems] The present invention includes a step of coating and forming a thin film of positive photoresist on the surface of a mirror-polished silicon wafer used as a substrate, and a step of forming a thin film of positive photoresist on the surface of a silicon wafer used as a substrate in a mirror-polished state. A step of exposing the positive photoresist thin film described above with modulated recording light, a step of developing the exposed positive photoresist thin film, and a silicon film using the developed positive photoresist thin film as a mask member. A step of forming a recess corresponding to the information signal to be recorded on the wafer by dry etching, and a step of forming a positive photoresist from the silicon wafer in which the recess corresponding to the information signal to be recorded is formed. a step of removing a thin film to obtain a mother board for manufacturing an information recording medium; a step of attaching and forming a stamper for manufacturing an information recording medium on the mother board for manufacturing the information recording medium by a plating method; A method for producing a stamper for producing an information recording medium, which comprises a step of peeling off a stamper for producing an information recording medium from a mother plate, and a substrate is obtained by depositing a metal thin film on the surface of a mirror-polished silicon wafer. a step of coating and forming a thin film of positive photoresist on the thin film of metal on the substrate;
A step of exposing the thin film of positive photoresist described above with recording light whose intensity is modulated by an information signal to be recorded, a step of developing the thin film of positive photoresist that has been exposed to light, and a step of developing the thin film of positive photoresist that has been exposed to light. A process of forming a recess corresponding to the information signal to be recorded by dry etching on the metal thin film of the substrate using a positive photoresist thin film as a mask member, and a process corresponding to the information signal to be recorded. A step of removing a thin film of positive photoresist from a substrate on which concave portions are formed in a thin metal film to obtain a base plate for producing an information recording medium, and a step of applying information to the base plate for producing the information recording medium by a plating method. Provided is a method for manufacturing a stamper for producing an information recording medium, which comprises a step of adhering and forming a stamper for producing the information recording medium, and a step of peeling the stamper for producing the information recording medium from a mother plate for producing the information recording medium.

[0007]

[Operation] A thin film of positive photoresist deposited on the mirror-polished surface of a silicon wafer used as a substrate is exposed to recording light whose intensity is modulated by the information signal to be recorded. develop. Using the developed thin film of positive photoresist as a mask member, a recess corresponding to the information signal to be recorded is formed on the silicon wafer by dry etching, and then a positive photoresist is etched onto the silicon wafer. The thin film is removed to obtain a mother plate for producing information recording media. A stamper for producing an information recording medium, which is formed by adhering to the above-mentioned mother board for producing an information recording medium by a plating method, is peeled off to obtain a stamper for producing an information recording medium. Further, a substrate is obtained by depositing a metal thin film on the surface of a mirror-polished silicon wafer. After the positive photoresist thin film formed on the metal thin film of the substrate is exposed to recording light whose intensity is modulated by the information signal to be recorded, the positive photoresist thin film is exposed. , the exposed positive photoresist thin film is developed, and the developed positive photoresist thin film is used as a mask member to form a recess corresponding to the information signal to be recorded on the metal thin film of the substrate by a dry etching method. After forming the positive photoresist thin film from the substrate, a mother plate for producing an information recording medium is obtained. A stamper for producing an information recording medium is attached and formed on the mother plate for producing the information recording medium by a plating method, and then the stamper for producing the information recording medium is peeled off from the mother plate for producing the information recording medium. Get a stamper.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, specific details of the method for manufacturing a stamper for manufacturing an information recording medium according to the present invention will be explained in detail with reference to the accompanying drawings. 1 and 2 are side sectional views used to explain the sequential steps in manufacturing a stamper for manufacturing an information recording medium by the method for manufacturing a stamper for manufacturing an information recording medium of the present invention. First, in Figure 1, (a
) is a silicon wafer 1 used as a substrate. This silicon wafer 1 is a single crystal silicon wafer that is widely used as a material for semiconductor integrated circuits, and has a thickness of, for example, 500 to 800 microns and a diameter of about 1.
It has a circular shape of 50 mm, and its surface is mirror-polished and has excellent flatness as a substrate for the master of an information recording medium. Reference numeral 2 in FIG. 1B is a thin film of positive photoresist coated on the surface of the silicon wafer 1 described above. The positive photoresist thin film 2 is formed by precisely cleaning and drying the single crystal silicon wafer 1, and then applying a positive photoresist, for example, a positive photoresist manufactured by Shipley Far East Co., Ltd. MP1400 with a thickness of 1000
It is coated onto the silicon wafer 1 by, for example, a spinner method so as to form a thin film having a thickness of 1500 angstroms.

The master disk of the information recording medium, which is formed by coating a positive photoresist thin film 2 of a predetermined thickness on a substrate made of a silicon wafer 1, is mounted on a turntable in a recording device and driven at a predetermined rotation speed. In the rotated state, the intensity of the information signal to be recorded is applied to the positive photoresist thin film 2 through the recording optical system 3 illustrated in FIG. 1(c). Exposure is performed using a minute spot of modulated argon laser light. In FIG. 1(c), 2a exemplifies the unexposed portion of the positive photoresist thin film 2, and 2b in FIG. 1(c) indicates the exposed portion of the positive photoresist thin film 2. Illustrated. The master disc of the information recording medium, which has been exposed to a minute spot of laser light whose intensity is modulated by the information signal to be recorded as described above, is then developed with a 0.2N alkaline developer. As a result, as shown in FIG. 1(d), the exposed portions 2b, 2b, . The media master is fired at a temperature of 120 degrees Celsius for one hour and then allowed to cool.

Next, (d) in FIG. 1 remaining on the positive photoresist thin film 2 on the master of the information recording medium.
Using the unexposed portions 2a, 2a, . . . as mask members, the substrate of the silicon wafer 1, which is the master of the information recording medium, is etched by dry etching. The dry etching performed on the substrate of the silicon wafer 1 which is the master of the information recording medium described above uses, for example, CF4 gas as the etching gas, and the CF4 gas is
5SCCM~30 at mTorr~30mTorr pressure
The substrate is cleaned by ashing the photoresist remaining on the silicon wafer in an oxygen plasma by converting the CF4 gas into oxygen at a flow rate of SCCM for a period of 2 to 15 minutes. FIG. 1 shows concave portions 1a, 1a, . . . corresponding to information signals to be recorded on the surface of a silicon wafer 1 used as a
A mother disk of the information recording medium formed as shown in (e) is obtained. The mother disk of the information recording medium is precisely cleaned using an alkaline detergent or the like and then dried.

Concave portions 1a, 1a, . . . corresponding to the information signals to be recorded are formed on the base plate of the information recording medium shown in FIG. 1(e) produced as described above. A conductive film 4 required for electroforming a stamper by electroforming is formed on the surface of the silicon wafer 1 by electroless plating, as shown in FIG. 1(f), and then After washing with water, an electroforming method is applied to the conductive film 4 to form a stamper 5 for producing an information recording medium by electroforming a metal (for example, nickel). (g
) is a diagram showing a state in which a stamper 5 for producing an information recording medium is made by electroforming a metal (for example, nickel) onto a mother plate of an information recording medium, and (h) in FIG. FIG. 3 is a diagram showing a state in which a stamper 5 for producing an information recording medium is peeled off from a mother plate. To produce the stamper 5 for producing information recording media by electroforming nickel on the mother plate of the information recording medium, for example, nickel sulfamate is used as the electrolyte, and the solution is heated at 50 degrees Celsius ± 2 degrees Celsius. 100mA per square centimeter with warm electrolyte
This is carried out by applying a current with a current density of 200 mA for 60 to 90 minutes. A stamper 5 for producing an information recording medium as shown in FIG. 1(h) is precisely cleaned using an alkaline detergent or the like and then dried. The mother disk of the information recording medium from which the stamper 5 for manufacturing the information recording medium has been peeled off can be used to manufacture a new stamper 5 for manufacturing the information recording medium after cleaning. A stamper 5 for producing information recording media can be produced. In addition,
On the surface of the silicon wafer 1 on which recesses 1a, 1a, ... corresponding to the information signals to be recorded on the mother board of the information recording medium are formed, there are formed a stamper necessary for electroforming the stamper by electroforming. Therefore, the conductive film 4 attached to the base of the information recording medium is peeled off from the base of the information recording medium together with the stamper 5 when the stamper 5 for manufacturing the information recording medium is peeled off from the base of the information recording medium. Therefore, the conductive film 4
Each time a new stamper 5 is made using the motherboard of the information recording medium, the silicon material is formed with recesses 1a, 1a, . . . corresponding to the information signals to be recorded on the motherboard of the information recording medium. It is necessary to form it on the surface of the wafer 1 by means such as electroless plating.

Next, a method for manufacturing a stamper for manufacturing an information recording medium according to the present invention, the steps of which are shown in FIG. 2, will be explained. In FIG. 2, (a) in FIG. 2 is a silicon wafer 1, and this silicon wafer 1 is the same as the silicon wafer 1 used as a substrate in the method for manufacturing a stamper for manufacturing an information recording medium of the present invention, which has already been described with reference to FIG. Similarly, single-crystal silicon wafers widely used as materials for semiconductor integrated circuits, for example, have a thickness of 500 mm.
It has a circular shape with a diameter of approximately 150 mm and a diameter of 150 mm to 800 microns, and its surface is mirror-polished and has excellent flatness as a substrate for the master of an information recording medium. FIG. 2B shows a substrate constructed by depositing a metal thin film 6 on the mirror-polished silicon wafer 1 as described above. The metal thin film 6 deposited and formed on the surface of the silicon wafer 1 described above is
For example, a thin film 6 of a suitable metal (for example, tungsten, molybdenum, tantalum, niobium, nickel) is deposited by applying a sputtering method, and a thin film of nickel is formed as the thin metal film 6 on the surface of the silicon wafer 1. 6
An example of the case of depositing and forming is as follows. Using a nickel target as a sputtering target, the flow rate of argon gas was 7.2SC.
CM~26.3SCCM, pressure 2mTorr~0.6m
Sputtering is performed for 1 minute to 10 minutes at an acceleration voltage of 410 volts to 505 volts to form a film with a thickness of 1250 angstroms to 135 angstroms on the surface of the silicon wafer 1.
0 angstrom nickel thin film 6 (metal thin film 6)
is deposited as shown in FIG. 2(b), and then the master of the information recording medium is precisely cleaned using an alkaline detergent or the like and then dried.

FIG. 2(c) shows the substrate shown in FIG. 2(b) with a positive photoresist thin film 2 coated on the metal thin film 6. There is. And the positive photoresist thin film 2
After precisely cleaning and drying the substrate, a positive photoresist, such as positive photoresist MP1400 manufactured by Shipley Far East Co., Ltd., is applied to a thickness of 100 mm.
It is coated onto the metal thin film 6 of the substrate by, for example, a spinner method so as to form a thin film having a thickness of 0 angstroms to 1500 angstroms.

The master disc of the information recording medium, which is formed by coating a positive photoresist thin film 2 of a predetermined thickness on a metal thin film 6 of a substrate, is mounted on a turntable in a recording device and rotated at a predetermined speed. While the photoresist is being driven and rotated by the number, the positive type photoresist thin film 2 is subjected to recording via the recording optical system 3 illustrated in FIG. 2(d). Exposure is performed using a minute spot of argon laser light whose intensity is modulated by an information signal. In FIG. 2(d), 2a represents an unexposed portion of the positive photoresist thin film 2, and 2b in FIG. 2(d) represents an exposed portion of the positive photoresist thin film 2. Illustrated. The master disc of the information recording medium, which has been exposed to a minute spot of laser light whose intensity is modulated by the information signal to be recorded as described above, is then developed with a 0.2N alkaline developer. As a result, as shown in FIG. 2(e), the exposed portions 2b, 2b, ... of the thin film 2 of the positive photoresist are removed, and the information is recorded. The media master is fired at a temperature of 120 degrees Celsius for one hour and then allowed to cool.

Next, (d) in FIG. 2 remaining on the positive type photoresist thin film 2 on the master of the information recording medium.
The thin metal film 6 on the substrate of the master of the information recording medium is etched by a dry etching method using the unexposed portions 2a, 2a, . . . shown in FIG. 6(f) as a mask member. As shown in FIG. 2, remaining portions 6a, 6a... and removed portions (concave portions) 6b, 6b correspond to the information signals to be recorded on the metal thin film 6 on the silicon wafer 1 in the substrate of the master of the information recording medium. ...is formed. Note that in the removed portions (recesses) 6b, 6b, where most of the metal thin film 6 has been removed by the etching process for the metal thin film 6, the metal thin film 6 is extremely thin. remains as an ultra-thin film. The dry etching performed on the thin metal film 6 on the substrate of the master of the information recording medium described above uses, for example, CF4 gas as the etching gas, and the CF4 gas is etched at a pressure of 5mTorr to 30mTorr and a flow rate of 5SCCM to 30SCCM. After that, the CF4 gas described above is converted to oxygen, and the photoresist remaining on the metal thin film 6 on the substrate of the master of the information recording medium is cleaned by ashing in oxygen plasma. By this, the convex portion 6 corresponding to the information signal to be recorded by the metal thin film 6 on the silicon wafer 1 in the master substrate of the information recording medium is formed.
A mother board of an information recording medium is obtained in which recesses 6b, 6b, . . . are formed as shown in FIG. 2(g).

Next, the (
Recesses 6b, 6b, . . . corresponding to the information signals to be recorded on the motherboard of the information recording medium shown in g).
An information recording medium is manufactured by electroforming a metal (for example, nickel) on the surface of the substrate (silicone wafer 1 and metal thin film 6) on which is formed, as shown in FIG. 2(h). A stamper 5 for use is formed. (h) of FIG. 2 is a diagram showing a state in which a stamper 5 for producing an information recording medium is made by electroforming a metal (for example, nickel) onto the mother plate of the information recording medium, and (i) of FIG. ) is a diagram showing a state in which a stamper 5 for producing an information recording medium has been peeled off from the mother plate of the information recording medium. In order to perform nickel electroforming on the mother plate of the information recording medium to make the stamper 5 for manufacturing the information recording medium, the surface of the mother plate of the information recording medium is cleaned using an alkaline detergent, acid, etc. After activation treatment,
After uniformly oxidizing the surface with a potassium dichromate solution to form a peeling film, for example, using nickel sulfamate as the electrolyte, the electrolyte at a temperature of 50 degrees Celsius ± 2 degrees Celsius is applied at 100 mA per square centimeter. 200mA
The process is carried out by applying a current with a current density of . A stamper 5 for producing an information recording medium as shown in FIG. 2(i) is precisely cleaned using an alkaline detergent or the like and then dried. Stamper 5 for producing information recording media
The mother disk of the information recording medium from which the information recording medium has been peeled off can be used for manufacturing a new stamper 5 for manufacturing a new information recording medium after cleaning. Stamper 5 can be produced.

The stamper 5 for producing an information recording medium produced by the method for producing a stamper for producing an information recording medium of the present invention comprising the above-described steps is used to mold and transfer onto a polycarbonate resin disk. Thus, a recorded information recording medium can be obtained. Regarding the optical disc obtained by molding and transferring onto a polycarbonate resin disc using the stamper 5 for producing an information recording medium produced by the method for producing a stamper for producing an information recording medium of the present invention, it is possible to use the stamper 5 for producing an information recording medium produced by the method of producing a stamper for producing an information recording medium according to the present invention. When we investigated various characteristic values, we found that compared to an optical disc obtained by molding and transferring onto a polycarbonate resin disc using a stamper for manufacturing information recording media made by a normal method of manufacturing a stamper for manufacturing information recording media. , an improvement of 0.01 dB to 0.02 dB was observed in amplitude modulation characteristics, an improvement of 0 to 0.05 dB in symmetry, and a 0.1 to 0.3% improvement in C1 error.
, an improvement of about 5% in crosstalk was obtained.

[0018]

[Effects of the Invention] As is clear from the above detailed explanation, the method for producing a stamper for producing an information recording medium of the present invention includes forming a stamper by adhering it to the mirror-polished surface of a silicon wafer used as a substrate. A thin film of positive photoresist is exposed and developed with recording light whose intensity is modulated according to the information signal to be recorded. Using the developed thin film of positive photoresist as a mask member, a recess corresponding to the information signal to be recorded is formed on the silicon wafer by dry etching, and then a positive photoresist is etched onto the silicon wafer. The thin film is removed to obtain a mother plate for producing information recording media. A stamper for producing an information recording medium is obtained by peeling off a stamper for producing an information recording medium which is formed by plating on the mother board for producing an information recording medium, or the surface of a silicon wafer in a mirror-polished state. A thin metal film is deposited on the substrate to obtain a substrate. After the positive photoresist thin film formed on the metal thin film of the substrate is exposed to recording light whose intensity is modulated by the information signal to be recorded, the positive photoresist thin film is exposed. , the exposed positive photoresist thin film is developed, and the developed positive photoresist thin film is used as a mask member to form a recess corresponding to the information signal to be recorded on the metal thin film of the substrate by a dry etching method. After forming the positive photoresist thin film from the substrate, a mother plate for producing an information recording medium is obtained. A stamper for producing an information recording medium is attached and formed on the mother plate for producing the information recording medium by a plating method, and then the stamper for producing the information recording medium is peeled off from the mother plate for producing the information recording medium. Since a stamper is obtained, the method for producing a stamper for producing an information recording medium of the present invention solves the conventional problems mentioned above, that is, it is possible to produce a stamper for producing an information recording medium with only one transfer operation. In the conventional manufacturing method of a stamper for manufacturing information recording media, a conductive film is formed on a glass substrate, and pits are formed by subjecting the conductive film to dry etching or wet etching. In production methods in which pits are formed by dry etching or wet etching on the substrate itself, the thickness is large due to the use of a glass master disk, which requires a large space in the stock. and the surface roughness of metal plates such as nickel, aluminum, and copper used as substrates.
All problems such as not being able to obtain a satisfactory flatness can be solved satisfactorily.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view used to explain the sequential steps in manufacturing a stamper for manufacturing an information recording medium by the method for manufacturing a stamper for manufacturing an information recording medium according to the present invention.

FIG. 2 is a side sectional view used to explain the sequential steps in manufacturing a stamper for manufacturing an information recording medium by the method for manufacturing a stamper for manufacturing an information recording medium according to the present invention.

[Explanation of symbols]

1... Single crystal silicon wafer used as a substrate, 2...
Thin film of positive photoresist, 2a... Unexposed portion of thin film 2 of positive photoresist, 2b... Exposed portion of thin film 2 of positive photoresist, 3... Recording optical system, 4... Conductive film, 5... Stamper, 6...metal film,

Claims (2)

[Claims] [Claim 1] A step of coating and forming a thin film of positive photoresist on the surface of a mirror-polished silicon wafer used as a substrate, and recording light whose intensity is modulated by an information signal to be recorded. A step of exposing the thin film of positive photoresist described above, a step of developing the exposed thin film of positive photoresist, and a step of recording on a silicon wafer by dry etching using the developed thin film of positive photoresist as a mask member. forming a concave portion corresponding to the information signal targeted by the method;
A step of removing a thin film of positive photoresist from a silicon wafer in which a concave portion corresponding to an information signal to be recorded is formed to obtain a mother plate for manufacturing an information recording medium, and a step of manufacturing the information recording medium as described above. Production of a stamper for producing information recording media, which comprises the steps of: adhering and forming a stamper for producing information recording media on a mother plate by plating; and peeling off the stamper for producing information recording media from the mother plate for producing information recording media. Method. 2. Obtaining a substrate by depositing a metal thin film on the surface of a mirror-polished silicon wafer; coating and forming a positive photoresist thin film on the metal thin film on the substrate; A step of exposing the thin film of positive photoresist described above with recording light whose intensity is modulated by an information signal to be recorded, a step of developing the thin film of positive photoresist that has been exposed to light, and a step of developing the thin film of positive photoresist that has been exposed to light. A process of forming a recess corresponding to the information signal to be recorded by dry etching on the metal thin film of the substrate using a positive photoresist thin film as a mask member, and a process corresponding to the information signal to be recorded. A step of removing a thin film of positive photoresist from a substrate on which concave portions are formed in a thin metal film to obtain a base plate for producing an information recording medium, and a step of applying information to the base plate for producing the information recording medium by a plating method. A method for producing a stamper for producing an information recording medium, comprising the steps of adhering and forming a stamper for producing a recording medium, and peeling the stamper for producing an information recording medium from a mother plate for producing an information recording medium.