JP2007122775A - Method for manufacturing master disk for preparing recording medium substrate, method for manufacturing stamper for preparing recording medium substrate, and method for manufacturing recording medium substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce complicatedness in a process for manufacturing a master disk using an inorganic photoresist, and to improve accuracy. <P>SOLUTION: Utilizing an inorganic photoresist capable of generating protrusions according to physical deformation by exposure, the master disk having a concave-convex pattern is prepared by the concavoconvex by the protrusions. Accordingly, developing processing step can be dispensed with, complicated works associated therewith are avoided, and the decrease in accuracy associated with the developing process is avoided. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method of manufacturing a recording medium substrate manufacturing master, a method of manufacturing a recording medium substrate manufacturing stamper, and a method of manufacturing a recording medium substrate, particularly in a recording medium having an information recording uneven surface.

In recording media for recording and storing various types of information, there is no limit to the increase in recording capacity, and accordingly, in the production of a recording medium substrate having an information recording uneven surface, formation of a highly accurate uneven pattern is required. .
On the other hand, improvement in productivity is desired in view of price reduction.

Usually, a recording medium substrate having an information recording uneven surface such as an optical disk is manufactured by producing a stamper on which a reverse uneven surface of the information recording uneven surface finally obtained is formed, injection molding using this, or 2P (Photopolymerization) Made by law.
The stamper is manufactured by first producing a master having an uneven surface corresponding to the information recording uneven surface, applying a metal plating to the uneven surface on the master, and peeling this to remove the uneven surface on the master. The transferred uneven surface is formed, and, for example, the stamper is formed by repeating this operation.

  This master is usually formed by applying an organic photoresist on a substrate by spin coating, pattern exposure according to the recorded information, and developing to form a concavo-convex pattern with the removed portion from which the photoresist layer is removed as a recess. To make it.

In the master production, an inorganic photoresist layer is sputtered on the substrate in place of the organic photoresist described above, and pattern exposure and development are similarly performed to produce a master having an uneven pattern. Has been proposed (see Patent Document 1).
When making a master using this inorganic photoresist, it has the advantages that the minimum exposure pit can be reduced and the sharpness of the contour of the pattern after development can be increased compared to the case of using an organic photoresist. It is excellent as a master production method for producing a large capacity, high density recording medium.

However, the development time of this inorganic photoresist is longer than that of the organic photoresist, and there is a problem in workability.
WO2004-034391

  The present invention relates to a master manufacturing method using an inorganic photoresist, which simplifies the process, solves workability problems, improves productivity, and consequently reduces the cost of the recording medium. The present invention provides a method for manufacturing a master for producing a recording medium substrate, a method for producing a stamper for producing a recording medium substrate, and a method for producing a recording medium substrate.

In the present invention, by utilizing the fact that an inorganic photoresist can generate protrusions due to physical deformation by exposure, a master having an uneven pattern with the protrusions and recesses is produced.
That is, the method for producing a master for producing a recording medium substrate according to the present invention is a method for producing a master for producing a recording medium substrate having an information recording uneven surface, and an inorganic photoresist layer is formed on a master substrate constituting the master. A step-and-projection pattern corresponding to recording information on the inorganic photoresist layer, generating protrusions corresponding to the recording information on the exposed portion, and having the protrusions on the surface of the inorganic photoresist layer. And forming an original plate having the concave-convex pattern of the inorganic photoresist layer on the original substrate.

  As described above, in the recording medium substrate manufacturing method according to the present invention, protrusions are generated by exposure without performing development processing, and a concavo-convex pattern corresponding to recording information is formed.

  The manufacturing method of a stamper for producing a recording medium substrate according to the present invention is a method of producing a stamper for producing a recording medium substrate having an information recording uneven surface, and an inorganic photoresist layer is formed on a master substrate constituting the master. A step of performing pattern exposure on the inorganic photoresist layer in accordance with recording information, generating protrusions on the exposed portion according to the recording information, and having the protrusions on the surface of the inorganic photoresist layer. An exposure process for forming a pattern, and a master having the uneven pattern formed of the inorganic photoresist layer on the master substrate is prepared, and the master is used as a recording medium manufacturing stamper, or a stamper is formed on the master. Forming at least one stamper having a concavo-convex pattern obtained by forming a material and transferring and reversing the concavo-convex pattern of the master from the master. Characterized by a through stamper obtained recording medium substrate manufactured stamper or more.

  As described above, in the manufacturing method of the recording medium substrate manufacturing stamper according to the present invention, the manufacturing of the master that generates the protrusions by the exposure without forming and forms the concavo-convex pattern according to the recording information is applied. An intended stamper is produced.

  The method for manufacturing a recording medium substrate according to the present invention is a method for manufacturing a recording medium substrate having an information recording uneven surface, and includes a stamper manufacturing step and a step of manufacturing the recording medium substrate using the stamper. The stamper manufacturing process includes a master manufacturing process. The master manufacturing process includes forming an inorganic photoresist layer on the master substrate constituting the master and recording information on the inorganic photoresist layer. An exposure step of forming a concavo-convex pattern having the projections on the surface of the inorganic photoresist layer by performing pattern exposure on the exposed portion to generate projections according to the recorded information on the exposed portion. A master having the concavo-convex pattern by the inorganic photoresist layer is prepared, and the master is used as a recording medium manufacturing stamper, or a stamper material is formed on the master. A stamper having a original master of the uneven pattern of the uneven pattern is transferred reversed, characterized in that the recording medium substrate manufactured stamper stamper obtained through at least once the step of peeling produced from the master.

  The present invention is also directed to a method for manufacturing the recording medium substrate, wherein the recording medium substrate having the information recording concave / convex surface is manufactured by injection molding using a mold having the recording medium manufacturing stamper disposed thereon. A recording medium substrate having a recording uneven surface is produced.

  Further, the present invention is the above-described method for manufacturing a recording medium substrate, wherein the step of producing the recording medium substrate having the information recording uneven surface forms a polymer resin layer on the substrate, and the recording is performed on the polymer resin layer. Pressing a medium production stamper to form an etching mask by the polymer resin layer, and etching the substrate through the etching mask to produce a recording medium substrate having the information recording uneven surface. .

As described above, in the present invention, in the production of the master, an inorganic photoresist is used, and pattern exposure according to the recorded information is performed. Therefore, by avoiding the development process, the manufacturing process and work are greatly simplified.
Incidentally, the development process for an inorganic photoresist is 15 times as long as 10 minutes, compared with the development process for a normal organic photoresist for about 40 seconds. Therefore, in the present invention, avoiding the development processing on the inorganic photoresist layer can greatly reduce the working time.

  Therefore, the manufacturing method of the recording medium substrate manufacturing stamper according to the present invention and the manufacturing method of the recording medium substrate according to the present invention, in which the manufacturing method of the master according to the present invention is applied and the stamper is manufactured from this master, are also highly workable. Will be improved.

  Embodiments of a recording medium substrate manufacturing method, a recording medium substrate manufacturing stamper manufacturing method, and a recording medium substrate manufacturing method according to the present invention will be described. However, the present invention is limited to these embodiments. It goes without saying that it is not something.

(Form example of manufacturing method of master for recording medium substrate production)
1A to 1C are schematic cross-sectional views in each step of an example of a method for producing a recording medium substrate producing master having an information recording uneven surface according to the present invention.
As shown in FIG. 1A, for example, a silicon (Si) substrate having a diameter of 200 mm and a thickness of 0.725 mm is prepared as a master substrate 1 constituting the master, and a heat storage layer 2 is formed on the smooth cleaned main surface. Then, an inorganic photoresist layer 3 is formed.
The heat storage layer 2 suppresses heat dissipation so that a required temperature rise occurs at the exposed portion of the inorganic photoresist layer 3 during exposure of the inorganic photoresist layer 3, and for example, amorphous silicon (a- Si) is formed by sputtering or the like.
On this, the inorganic photoresist layer 3 is formed by sputtering etc. to 70 nm, for example.
The inorganic photoresist layer 3 can be composed of an inorganic photoresist of an incomplete oxide of a metal including a transition metal, for example, an incomplete oxide of tungsten (W) and an incomplete oxide of molybdenum (Mo). .

As shown in FIG. 1B, the inorganic photoresist layer 3 is exposed with a pattern corresponding to the information recording of the finally obtained recording medium, that is, with a light emission waveform. This exposure operation will be described in detail later.
By this exposure, as shown in FIG. 1C, the inorganic photoresist layer 3 is limitedly bulged to generate protrusions 4 in the exposed portion of the inorganic photoresist layer 3. It is known that the protrusions 4 can be generated, and the target master can be selected by selecting the thickness of the inorganic photoresist layer 3, the exposure conditions, that is, the exposure power, the heat storage effect of the heat storage layer 2, and the like. The necessary shape, height, etc. can be selected. That is, it is possible to form a desired uneven pattern according to the wavelength of the reproduction light.
In this way, the surface of the inorganic photoresist layer 3 itself is formed into a concavo-convex pattern according to the recording information, and thus a master 5 for producing a recording medium substrate having the concavo-convex pattern is obtained.
That is, the master 5 is manufactured using an inorganic photoresist, but development processing is not performed on this.

The master 5 produced in this way has an uneven pattern on the surface made of a metal oxide and has excellent mechanical strength. Therefore, the master 5 itself can be used as a stamper for forming a recording medium substrate.
Alternatively, a stamper for forming a recording medium substrate can be transferred from the master 5.

Next, an embodiment of a method for producing a stamper for producing a recording medium substrate according to the present invention will be described.
[Embodiment example of manufacturing method of stamper for producing recording medium substrate]
2A to 2D are schematic cross-sectional views in each step of an example of a manufacturing method of a recording medium substrate manufacturing stamper having an information recording uneven surface according to the present invention.
In the production of this stamper, the master 5 shown in FIG. 1C was produced by the above-described production method of the present invention.
Then, as shown in FIG. 2A, a first stamper material layer 7 is deposited on the concave / convex pattern 6 of the master 5 by, for example, nickel (Ni) electroforming plating.
By peeling this stamper material layer 7 from the master 5, as shown in FIG. 2B, a first stamper 9 is formed in which a first concavo-convex pattern 8 in which the concavo-convex pattern 6 of the master 5 is reversely transferred is formed. Is done.
As shown in FIG. 2C, a second stamper material layer 10 is similarly formed on the first uneven pattern 8 of the first stamper 9 by, for example, nickel (Ni) electroforming plating.
As shown in FIG. 2D, the second stamper material layer 10 is peeled from the first stamper 9, thereby forming the second uneven pattern 11 in which the first uneven pattern 8 is reversely transferred. The stamper 12 is formed.
The second stamper 12 has the same pattern as the concavo-convex pattern 8 of the master 5 and serves as a stamper for forming a recording medium substrate.

Next, a method for manufacturing a recording medium substrate according to the present invention will be described.
In this case, the master 5 shown in FIG. 1C is produced and used as a stamper, or the second stamper 12 shown in FIG. 2D is produced and used as a stamper to produce a recording medium substrate.

[First Embodiment of Manufacturing Method of Recording Medium Substrate]
FIGS. 3A to 3C are schematic cross-sectional views of a process for manufacturing a substrate in this embodiment and each process for manufacturing a recording medium, in this example, an optical disk, using the recording medium substrate obtained thereby.
In this embodiment, as shown in FIG. 3A, the above-described master 5 or the stamper by the second stamper 12 is placed in an injection mold (not shown) as an injection molding stamper 20, and for example, polycarbonate resin is used. Injection molding.
Then, by removing the molded body from this mold, as shown in FIG. 3B, a recording medium substrate 22 on which an information recording uneven surface 21 to which the uneven pattern 6 or 8 of the stamper 20 is transferred in reverse is formed, for example, an optical disk substrate. Molded.

  Then, as shown in FIG. 3C, a reflection film 23 and a light-transmitting cover layer 24 are formed on the surface of the recording medium substrate 22 on which the information recording uneven surface 21 is formed, and a recording medium 25 such as a ROM (Read Only Memory). Type optical disc is manufactured.

  In the first embodiment of the method for manufacturing the recording medium substrate described above, the recording medium substrate is formed by injection molding. However, the method for manufacturing the recording medium substrate is limited to the method of the first embodiment described above. Instead, various manufacturing methods using a stamper can be employed. For example, a target recording medium substrate can be formed by a so-called nanoimprint method. An embodiment in this case is illustrated.

[Second Embodiment of Manufacturing Method of Recording Medium Substrate]
4A to 4D are schematic cross-sectional views of a manufacturing method of a recording medium substrate in this embodiment and each manufacturing process for manufacturing a recording medium, in this example, a patterned recording medium for magnetic recording, using this recording medium substrate. .
In this embodiment, as shown in FIG. 4A, a substrate 31 constituting a recording medium substrate such as a glass substrate is prepared, and a magnetic thin film 38 is formed on the smooth and clean surface by sputtering of a metal magnetic material, for example. An etching mask layer 32 is formed on the entire surface of the magnetic thin film 38 by coating, for example, a polymer resin serving as an etching mask for the magnetic thin film 38.

  On the etching mask layer 32, as shown in FIG. 4B, the imprint stamper 33 by the master 5 or the second stamper 12 described above is pressed on the concave / convex pattern side, and the protrusion (projection) of the stamper 33 Then, an opening 34 is formed in the etching mask layer 32. In this case, if the complete opening 34 cannot be penetrated by the pressing of the stamper 33, the mask material remaining in the opening is removed by, for example, RIE (Reactive Ion Etching) to form the opening 34. Further, as shown in FIG. 4C, the recess 35 is formed by etching the surface of the magnetic thin film 38 to a required depth through the opening 34.

  Next, as shown in FIG. 4D, when the etching mask layer 32 is removed, a recording medium 39 having an information uneven surface 36 formed on the surface according to the recording information by the concave portion 35, in this example, a patterned recording medium for magnetic recording. It is formed.

As described above, according to the present invention, when producing a master having a concavo-convex pattern, the inorganic photoresist layer 3 is subjected to pattern exposure according to recorded information as shown in FIG. 1B. In this case, the projection 4 generated by this exposure determines the information uneven surface in the recording medium to be finally formed, and affects the reproduction signal characteristics. Control of the exposure amount at the time of exposure is important.
An example of this exposure control will be described. FIG. 5 is a schematic block diagram of an example of an exposure apparatus that performs this exposure control.

As shown schematically in FIG. 5, this exposure apparatus irradiates a turntable 51 on which a master substrate 1 on which an inorganic photoresist layer 3 is formed, and light having a wavelength of, for example, 405 nm with respect to the inorganic photoresist layer 3. A light source unit 52 by a laser light source, an optical system 53, and a photodetector 54.
The optical system 53 includes an objective lens 55, a beam splitter 70, a collimator lens 56, a condenser lens 57, and the like.

The turntable 51 is disposed on a stage that is adapted to move in the radial direction, and is rotated by a spindle motor 58.
The light source unit 52 is driven and controlled by the drive control circuit 60 in accordance with a supply signal from the signal source 59.
Further, on the output side of the photodetector 54, there is a low-pass filter 61 and, for example, an oscilloscope 62 for observing the output.
In the above-described configuration, although not shown, the objective lens has a mechanism whose movement is controlled by, for example, a biaxial actuator, and controls focusing control and the like.

  With this exposure apparatus, the inorganic photoresist layer 3 on the master substrate 1 is first subjected to, for example, one round of test exposure for determining exposure conditions. In this exposure, in the case of information recording modulation scheme, for example, 17PP modulation, the 17PP modulation scheme signal (2T to 9T mark signal) is supplied from the signal source 59 to the drive control circuit 60, and thereby the light source section 52. The modulated exposure laser beam is emitted from the collimator lens 56, the beam splitter 70, and the objective lens 55, and condensed and irradiated onto the rotated inorganic photoresist layer 3 of the master substrate 1. Pattern exposure is performed with the modulated light.

The characteristic of information recording on the recording medium substrate that is finally obtained by the concavo-convex pattern formed by the projections 4 generated by this exposure is determined. Therefore, the reproduction information of the recorded information is indirectly judged by reproducing the unevenness information by the protrusions 4, and the exposure conditions for obtaining the desired reproduction characteristics are determined.
For this reason, in order to avoid the influence of noise generation and the like on the light source unit 52 due to the recording power from the exposure light source unit 52 on the above-described exposure track, that is, the direct current component smaller than the exposure power and the return light. Further, for example, the laser beam modulated by a signal superposed with a high frequency of 600 MHz is similarly rotated through the collimator lens 56, the beam splitter 70, and the objective lens 55, and the tip of the substrate 1 on the inorganic photoresist layer 3 is rotated. The track recorded in the above is scanned. Then, the return light, that is, the reflected light is branched by the beam splitter 70 and is received by the photodetector 54 through the condenser lens 57.

The output detected from the photodetector 54 is an output in which the above-described direct current component is superimposed on the high frequency, but this detection output is introduced into the low-pass filter 61 to remove the high frequency component, and by the intended exposure. The recorded information by the formed protrusion is taken out as a reproduced signal. Accordingly, by observing the reproduction signal with, for example, the oscilloscope 62, it is possible to determine whether the reproduction is good or not, and, in turn, the quality of the protrusion shape due to exposure. Then, the exposure conditions for obtaining a good protrusion shape are determined.
The target information recording is exposed under the optimum exposure conditions obtained in this way.
In this way, it is possible to manufacture an information recording medium substrate having an information uneven surface with excellent reproduction characteristics.

FIG. 6 is a photograph of an eye pattern by the oscilloscope 62 of a reproduction signal reproduced from the master obtained by the present invention.
In this case, the master was produced by sputtering the heat storage layer 2 of about 80 nm thick and the inorganic photoresist layer 3 of about 70 nm thick on the master base 1 made of Si substrate.
As the exposure laser beam, a laser beam having a wavelength of 405 nm and a peak power of about 9 mW was used. This laser beam was modulated so as to have (n−1) T comb-shaped waveforms in accordance with the pit mark length (2T to 9T) of the 17PP signal.
At this time, the duty of the comb waveform was about 30% and the clock frequency was 66 MHz. This laser beam was condensed on the inorganic photoresist 3 with an objective lens having a numerical aperture (NA) of 0.95, and exposed by rotating the master at a rotational speed of 4.92 m / s.
The eye pattern shown in FIG. 6 is an intensity that is reflected back from the master by using a reproducing laser beam with an average power of about 0.2 mW and a high frequency modulation of about 600 MHz after exposure on concentric circles under these conditions. The signal is monitored by an oscilloscope 62 via a photodetector 54 and a low-pass filter 61.
FIG. 7 shows a track of a master having a film configuration similar to that described above, and is exposed with a track pitch of 320 nm while being modulated with a DC signal, that is, a comb-shaped waveform, instead of exposure with the above-described 17PP signal. It is a transmission electron microscope (TEM) image of the cross section of the width direction (radial direction). As is apparent from the TEM photograph, the protrusions having a uniform shape are formed. In this TEM image, the uppermost layer is a carbon layer formed for surface protection during TEM observation.

As described above, according to the present invention, the protrusions are generated by appropriate pattern exposure, and the development process is avoided by using the protrusions as uneven patterns on the master, thereby greatly simplifying the manufacturing process and operation.
Compared with the development processing in a normal organic photoresist, in the case of an inorganic photoresist, the development processing is avoided in spite of a long time, so that the working time can be greatly reduced.
In addition, since the developing solution is used in the developing process, handling of the developing solution, complicated operations associated therewith, control, maintenance of the apparatus, etc. can be avoided, thereby greatly improving workability and occurrence of defective products. This leads to an improvement in the rate.

  Therefore, the manufacturing method of the recording medium substrate manufacturing stamper according to the present invention and the manufacturing method of the recording medium substrate according to the present invention, in which the manufacturing method of the master according to the present invention is applied and the stamper is manufactured from this master, are also highly workable. In addition, the yield is improved.

FIGS. 4A to 4C are schematic cross-sectional views in each step of an example of a method of manufacturing a recording medium substrate manufacturing master for manufacturing a recording medium having an information recording uneven surface according to the present invention. A to D are schematic cross-sectional views in each step of an example of a method for manufacturing a stamper for producing a recording medium substrate having an information recording uneven surface according to the present invention. FIGS. 4A to 4C are schematic cross-sectional views of a manufacturing method of a recording medium substrate and each process of an example of manufacturing an optical disc using the substrate. A to D are schematic cross-sectional views of a manufacturing method of a recording medium substrate and each process of another example of manufacturing a patterned recording medium for magnetic recording using the substrate. It is a schematic block diagram of an example of the exposure apparatus used for the master manufacture by this invention. It is a photograph figure of the eye pattern by the oscilloscope of the reproduction signal reproduced from the original disk obtained by the present invention. It is a TEM photograph figure of the section of the original disk by the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Master base body, 2 ... Thermal storage layer, 3 ... Inorganic photoresist layer, 4 ... Protrusion, 5 ... Master disk, 6 ... Uneven pattern, 7 ... 1st stamper material, 8 ... 1st 9 ... 2nd uneven pattern, 10 ... 2nd stamper material layer, 11 ... 2nd uneven pattern, 12 ... 2nd stamper, 20 ... Injection molding stamper, 21 ... Information recording concave / convex surface, 22 ... recording medium substrate, 23 ... reflective film, 24 ... light-transmitting cover layer, 25 ... recording medium (optical disk), 31 ... substrate, 32 ... etching mask layer, 33 ... ... imprint stamper, 34 ... opening, 35 ... concave, 36 ... information uneven surface, 37 ... recording medium substrate, 38 ... magnetic thin film, 39 ... recording medium (patterned recording medium for magnetic recording) , 51 ... Turntable, 52 ... Light source, 53 ... Light System 54... Photodetector 55... Objective lens 56. Collimator lens 57. Condensing lens 58. Spindle motor 59 59 Signal source 60. Light source drive control circuit 61. ... Low-pass filter, 62 ... Oscilloscope, 70 ... Beam splitter

Claims (7)

A method of manufacturing a master for producing a recording medium substrate having an information recording uneven surface,
Forming an inorganic photoresist layer on a master substrate constituting the master;
The inorganic photoresist layer is subjected to pattern exposure according to recorded information, and a projection according to the recorded information is generated at the exposed portion to form an uneven pattern having the projection on the surface of the inorganic photoresist layer. An exposure process,
A method for producing a master for producing a recording medium substrate, comprising producing a master having the concavo-convex pattern of the inorganic photoresist layer on the master base.   2. The method of manufacturing a master for manufacturing a recording medium substrate according to claim 1, wherein the inorganic photoresist layer is made of an incomplete oxide of a metal containing a transition metal.   The incomplete oxide of the metal containing the transition metal constituting the inorganic photoresist layer is composed of an incomplete oxide of tungsten (W) and an incomplete oxide of molybdenum (Mo). A method for producing a master for producing a recording medium substrate as described in 1. A method of manufacturing a stamper for producing a recording medium substrate having an information recording uneven surface,
Forming an inorganic photoresist layer on a master substrate constituting the master;
The inorganic photoresist layer is subjected to pattern exposure according to recorded information, and a projection according to the recorded information is generated at the exposed portion to form an uneven pattern having the projection on the surface of the inorganic photoresist layer. An exposure process,
Producing a master having the concavo-convex pattern of the inorganic photoresist layer on the master substrate,
The master is used as a recording medium manufacturing stamper, or a stamper material is formed on the master and a stamper having a concavo-convex pattern obtained by transferring and reversing the concavo-convex pattern on the master is peeled off from the master. A method for producing a stamper for producing a recording medium substrate, wherein the stamper obtained after the process is used as a stamper for producing a recording medium substrate. A method of manufacturing a recording medium substrate having an information recording uneven surface,
A stamper fabrication process;
Producing the recording medium substrate with the stamper,
The stamper manufacturing process includes a master disk manufacturing process,
The master production process is
Forming an inorganic photoresist layer on a master substrate constituting the master;
The inorganic photoresist layer is subjected to pattern exposure according to recorded information, and a projection according to the recorded information is generated at the exposed portion to form an uneven pattern having the projection on the surface of the inorganic photoresist layer. An exposure process,
Producing a master having the concavo-convex pattern of the inorganic photoresist layer on the master substrate,
The master is used as a recording medium production stamper, or a stamper material is formed on the master and a stamper having a concavo-convex pattern obtained by transferring and reversing the concavo-convex pattern of the master is peeled off from the master. Make a stamper that was obtained more than once,
A method of manufacturing a recording medium substrate, comprising: forming a recording medium substrate having an information recording uneven surface by forming the information recording unevenness of the recording medium substrate by the recording medium substrate manufacturing stamper. The production process of the recording medium substrate having the information recording uneven surface,
6. The method of manufacturing a recording medium substrate according to claim 5, wherein the recording medium substrate having the uneven surface for recording information is manufactured by injection molding using a mold in which the stamper for recording medium preparation is arranged. The production process of the recording medium substrate having the information recording uneven surface,
Forming a polymer resin layer on the substrate, pressing the recording medium preparation stamper on the polymer resin layer, forming an etching mask by the polymer resin layer, etching the substrate through the etching mask, and 6. The method for manufacturing a recording medium substrate according to claim 5, wherein a recording medium substrate having an information recording uneven surface is manufactured.