JPH06274946A - Production of stamper - Google Patents

Abstract

PURPOSE:To decrease the time for polishing the back surface of a stamper and to reduce the cost. CONSTITUTION:The stamper is produced by forming a rugged pattern and subjecting the stamper to electroforming by using a glass master plate with a conductive film formed as a cathode 15. In this process, prior to electroforming, a liquid for electroforming is sprayed from an injection nozzle 7 to the cathode 15 for one or two minutes. Then, during electroforming, the liquid for electroforming is injected and sprayed from the nozzle 7 to the cathode in every 15-20min to form an electroforming film of specified thickness. Thereby, even when gas is produced in the electroforming tank 3, gas depositing on the glass master plate can be efficiently removed, and production of projections or recesses in the electroforming film can be prevented and surface roughness of the electroforming film is improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to optical recording / recording of information.
The present invention relates to a stamper manufacturing method in which a stamper used when a large number of reproduction optical recording media is copied is electroformed.

[0002]

2. Description of the Related Art When mass-producing optical recording media such as magneto-optical disks and optical disks by injection molding or the like, a stamper on which a fine concavo-convex pattern such as a pre-groove is previously formed is used for manufacturing optical recording media. Used as a master. Conventionally, in order to manufacture this stamper, first, a glass substrate is manufactured by coating a glass substrate with photoresist, cutting it with a laser beam or the like, and then developing it to form an uneven pattern of a desired shape. To do.

Then, a conductive film is formed on the glass master having such a concavo-convex pattern by a method such as sputtering or vapor deposition, and the conductive film is used as a cathode to perform electroforming. An electroformed film made of metal is formed with a predetermined film thickness. After that, the stamper is produced by separating the glass master and the electroformed film.

In the above conventional stamper manufacturing method,
In the electroforming process on the glass master, an electroforming apparatus as shown in FIG. 5 is used. In the electroforming tank 23 containing the electroforming liquid,
The master glass holder for holding the glass master disk is arranged as a cathode 28 in a state in which the glass master disk is tilted downward so as to face the tilted anode 22 substantially in parallel with the anode 22. To be done.

Since the glass master is provided downward, the conductive film formed on the glass master even if insoluble dust or the like is generated from the anode 22 during electroforming. The above-mentioned dust and the like are not attached to the surface, and foreign substances due to this dust and the like are not deposited.

On the other hand, when gas is generated in the electrolytic cell 23, the gas adheres to the surface of the glass master disk held downward by the master disk holder as the cathode 28, or the glass master disk is fixed to the master disk holder. By confining the gas between the master plate and the glass master plate, the generation rate of the electroformed film becomes non-uniform, and the formed electroformed film has a protrusion,
There was a problem that a dent was generated.

Therefore, a nozzle for injecting an electroforming liquid is provided in the electroforming tank 23, and a jet flow of the electroforming liquid is applied to the cathode 28 to remove the gas adhering to the glass master disk. There has been proposed a method of preventing the occurrence of such protrusions and depressions.

[0008]

However, in the above method, since the jet flow is continuously applied from the start of electroforming to the end of electroforming in order to eliminate the protrusions and dents, the back surface of the stamper is formed when the stamper is completed. There is a problem in that the surface roughness of the electroformed film is deteriorated, which causes a great loss of time in the subsequent polishing step in the stamper manufacturing step, resulting in an increase in cost.

The present invention has been made in view of the above conventional problems, and an object thereof is to generate a gas in an electroforming tank when a stamper is manufactured by electroforming, and the gas is
When adhered to the surface of the glass master or when it enters the master press, these gases are efficiently removed to prevent the formation of protrusions and dents in the formed electroformed film, and to improve the surface roughness of the formed electroformed film. It is to provide a method for manufacturing a stamper that can reduce the manufacturing cost by shortening the time required for the back surface polishing step of the stamper by improving the height.

[0010]

In order to solve the above-mentioned problems, the stamper manufacturing method according to the invention of claim 1 performs electroforming on a master having a fine relief pattern formed on its surface. In the method of manufacturing a stamper for producing a stamper to be used for replicating the fine relief pattern, in an electroforming tank containing an electroforming liquid, the electroforming liquid is applied to the master before starting the electroforming process. It is characterized by applying a jet stream of.

In order to solve the above-mentioned problems, the stamper manufacturing method according to the second aspect of the present invention performs electroforming on a master having a fine undulation pattern formed on the surface thereof, whereby the above-mentioned fine In a method of manufacturing a stamper for producing a stamper to be used for replicating an undulation pattern, while intermittently applying a jet of an electroforming liquid to the master at a predetermined interval in an electroforming tank containing an electroforming liquid, It is characterized by performing electroforming.

In order to solve the above-mentioned problems, the stamper manufacturing method according to the invention of claim 3 is the above-mentioned claim 2.
In the method for manufacturing a stamper described, a spray nozzle is used to apply a jet of electroforming liquid to the master disk, and by vertically moving this spray nozzle, the spray nozzle's spray port is regularly displaced from the master disk. I am trying.

In order to solve the above problems, the stamper manufacturing method according to the invention of claim 4 is the same as that of claim 2
In the method of manufacturing a stamper described, a jet nozzle is used to apply a jet of electroforming liquid to the master disc, and by rotating this jet nozzle, the jet port of the jet nozzle is regularly displaced from the master disc. There is.

In order to solve the above-mentioned problems, the stamper manufacturing method according to the invention of claim 5 performs electroforming on a master having a fine relief pattern formed on the surface thereof, whereby the above-mentioned fine pattern is formed. In a stamper manufacturing method for producing a stamper for use in duplicating an undulating pattern, a step of applying a jet of electroforming liquid to the master in an electroforming tank containing an electroforming liquid, and a step of performing electroforming treatment It is characterized by performing and alternately.

[0015]

According to the method of claim 1, the gas generated in the electroforming tank and adhering to the master can be removed by applying a jet of the electroforming liquid to the master before starting the electroforming. Therefore, it is possible to prevent the formation of protrusions or depressions in the formed electroformed film. Further, before the start of electroforming, by applying a jet of electroforming liquid to the master, by removing the gas adhering to the master, to continuously perform a jet of electroforming liquid to the master while performing electroforming. Since the surface roughness of the electroformed film, which is the back surface of the stamper when the stamper is completed, can be improved as compared with the case of applying the stamper, the time required for polishing the back surface of the stamper following the electroforming step can be shortened.

According to the method of claim 2, when the jet of the electroforming liquid is applied to the master, for example, the jetting of the electroforming liquid is temporarily stopped or the jet is applied to the master. Since the jet nozzle is used and the jet port of the jet nozzle is regularly displaced from the master disk, by vertically moving the jet nozzle as in claim 3 or rotating the jet nozzle as in claim 4. The electroforming is performed while the jet stream is intermittently applied to the master.

As described above, even during electroforming, the jet of the electroforming liquid is intermittently applied to the master so that the gas adhering to the master can be efficiently removed, and the electroformed film is formed. It is possible to prevent the generation of protrusions and depressions in Further, as compared with the case where the jet flow of the electroforming liquid is continuously applied to the master disk from the start to the end of electroforming as in the above-mentioned conventional method, in this method, the master disk is electrically charged. Since the time for performing only the normal electroforming without applying the jet of the casting liquid is also provided, the surface roughness of the electroformed film is improved, and the time required for the subsequent back surface polishing of the stamper can be shortened.

Further, according to the method of claim 5, the step of applying a jet of electroforming liquid to the master and the step of performing electroforming are alternately performed at predetermined intervals, for example. That is, while the jet of the electroforming liquid is being applied to the master, the electroforming is temporarily interrupted, so that the gas adhering to the master can be efficiently removed and the surface of the electroformed film formed. The roughness can be further improved, and the time can be shortened in the subsequent stamper back surface polishing step.

[0019]

【Example】

[Embodiment 1] One embodiment of the present invention will be described with reference to FIGS.
The explanation is based on the following.

First, as shown in FIG. 2A, a photoresist 2 is applied on a flat glass substrate 1, and then a photoresist 2 is applied.
As shown in FIG. 7, a predetermined position of the photoresist 2 is irradiated with a laser beam 20 by using an Ar laser or the like to be exposed.
After that, the photoresist 2 is developed to form a concavo-convex pattern 2a having fine undulations, as shown in FIG. Next, this glass master 9
As shown in FIG. 3D, a conductive film 11 made of nickel or the like is formed by, for example, sputtering or vapor deposition in order to impart conductivity to the cathode, which is used as a cathode for electroforming subsequently performed.

Subsequently, the glass master 9 is electroformed using an electroforming apparatus as shown in FIG. This electroforming apparatus includes an electroforming tank 3 containing an electroforming liquid 14 such as a nickel sulfamate plating liquid, and an upper lid 5 that covers the upper surface of the electroforming tank 3. One side surface of the electroforming tank 3 is composed of an anode 6 that is provided so as to be inclined. As the anode 6, a nickel ball placed in a titanium basket and covered with a cotton cloth so as to suppress the outflow of dust and the like is used.

The glass master 9 on which the conductive film 11 is formed is fixed to the master holder 8 by master presses 10 ... As shown in FIG. That is, the glass master 9 is set in the recess 8 a of the master holder 8 so that the conductive film 11 is on the outside, and the glass master 9 is set in the peripheral portion of the master holder 8.
A master disk holder 10 ... Between which the master disk holder 8 and the master disk holder 8 are sandwiched and pressed from both sides is attached, and this is used as a cathode 15 for electroforming.

The glass master 9 mounted on the master holder 8 is subjected to a pretreatment for electroforming, and then the glass master 9 is turned downward, as shown in FIG.
The cathode 15 is immersed in the electrocasting tank 3 so as to face the anode 2 in a substantially parallel manner with the cathode 15 at a predetermined interval. Further, between the anode 6 and the cathode 15 in the electrocasting tank 3, an injection nozzle 7 for injecting an electroforming liquid toward the cathode 15 is provided.

First, the master disk holder 8 is rotated by the driving force of the motor 4, the electroforming liquid is sprayed from the spray nozzle 7, and a jet stream is applied to the surface of the glass master disk 9 serving as the cathode 15. As a result, the gas that adheres to the surface of the glass master 9 or is trapped between the glass master 9 and the master holder 10 is removed. In this state, the jet of the electroforming liquid is applied to the cathode 15 for about 1 to 2 minutes, for example, and then the injection from the injection nozzle 7 is stopped and the electroforming is started at a predetermined current value. Next, for a predetermined time, for example, about 15 to 2
After electroforming for 0 minutes, jetting of the electroforming liquid from the jet nozzle 7 is started again.

In this way, the injection nozzle 7 is provided at a predetermined interval.
While repeating the start and stop of the jet from
The electroformed film 12 as shown in (e) has a predetermined thickness, for example 3
Electroforming is continued until it becomes 00 μm. When the electroforming is completed, the electroformed film 12 is peeled off from the glass master 9 at the interface between the concavo-convex pattern 2a formed on the glass substrate 1 and the conductive film 11, so that the stamper as shown in FIG. 1
3 is obtained. After that, the back surface of the stamper 13 (the surface of the electroformed film during electroforming) is polished, and the stamper manufacturing process is completed.

As described above, in the stamper manufacturing method according to the present embodiment, before the electroforming is started or while the electroforming is performed, the glass master 9 is electrically charged at a predetermined time interval. When a gas is generated in the electroforming tank 3 by applying the jet flow of the casting liquid, the gas adhered to the surface of the glass master 9 or
The gas trapped between the glass master 9 and the master press 10 can be efficiently removed. As a result, the generation rate of the electroformed film 12 can be prevented from becoming nonuniform on the surface thereof, and the occurrence of protrusions or depressions in the electroformed film 12 or on the surface of the electroformed film 12 is reduced.

Further, since the electrolytic solution is jetted from the jet nozzle 7 to the glass master 9 intermittently at a predetermined interval, the jet flow is continuously applied to the glass master during electroforming. The surface roughness of the produced electroformed film is improved as compared with the case of continuing. Therefore, in the stamper manufacturing process, the time required for polishing the back surface of the stamper (the surface of the electroformed film formed during electroforming) subsequent to the electroforming step is shortened, and the cost can be reduced.

When performing electroforming, the time and interval for applying the jet of electroforming liquid to the glass master are not limited to those in the above-mentioned embodiment, and the nature of the electroforming liquid used and It may be set arbitrarily according to the thickness of the electroformed film to be formed.

[Embodiment 2] Next, another embodiment of the present invention will be described below with reference to FIG. For convenience of explanation, members having the same functions as those of the members shown in the drawings of the above-described embodiments are designated by the same reference numerals, and the description thereof will be omitted.

In the stamper manufacturing method according to this embodiment,
An electroforming apparatus as shown in FIG. 4 is used to perform electroforming on a glass master plate to produce a stamper. Since the glass master is manufactured by the same method as in the above-described Example 1 until the concavo-convex pattern is formed on the glass substrate and the conductive film is further formed thereon, the description thereof will be omitted.

In the electroforming apparatus, a cathode 15 having the same structure as that of the first embodiment is attached to the tip of the motor 4 and immersed in the electroforming tank 3. The cathode 15 has an electroforming liquid. A vertical movement motor 16 for vertically moving the jet nozzle 7 to which the jet flow of, and a rotation motor 19 for rotating the jet nozzle 7 are provided at the lower ends of the jet nozzles 7, respectively.

The injection nozzle 7 is urged downward by the urging force of the springs 18 and 18, and the lower end portion of the injection nozzle 7 is in contact with the cam 17 attached to the vertical movement motor 16. That is, the injection nozzle 7 moves up and down when the cam 17 is rotated by the driving force of the vertical movement motor 16. Further, the injection nozzle 7 is
It is adapted to rotate by the driving force of the rotation motor 19.

When performing electroforming on the glass master, first, a jet of electroforming liquid is ejected from the jet nozzle 7 to make the cathode 15
To hit. After the electroforming liquid jet is applied to the cathode 15 for about 1 to 2 minutes, electroforming is started at a predetermined current value, and at the same time, the vertical motion motor 16 and the rotation motor 19 are driven to eject the injection nozzle 7. Start vertical movement and rotation of. In this state, electroforming is performed until the film thickness of the electroformed film reaches a predetermined thickness, for example, 300 μm.

As described above, by performing electroforming while applying a jet flow from the injection nozzle 7 to the glass master disk, it is possible to prevent the formation of projections or depressions in the formed electroformed film. In addition, even if the jet nozzle 7 is rotated or moved up and down to continuously eject the jet flow from the jet nozzle 7, the glass master disk is only hit intermittently with the jet flow. The surface roughness of the back side of the stamper becomes good, and the time required for the subsequent polishing process can be shortened. Therefore, unlike the first embodiment, it is not necessary to interrupt or restart the injection from the injection nozzle 7 at a predetermined time interval.

[Embodiment 3] Next, another embodiment of the present invention will be described below with reference to FIG. For convenience of explanation, members having the same functions as those of the members shown in the drawings of the above-described embodiments are designated by the same reference numerals, and the description thereof will be omitted.

In this embodiment, the glass master is electroformed by the same electroforming apparatus as in the first embodiment (see FIG. 1) to produce a stamper. That is, an electroforming step is performed after forming a conductive film on a glass master having an uneven pattern formed of photoresist. In this electroforming step, as in the case of Example 1, the ejection of the electroforming liquid from the injection nozzle to the glass master is performed at a predetermined interval, for example, every 15 to 20 minutes, for about 1 to 2 minutes. Unlike the first embodiment, electroforming is stopped while the jet stream is being applied to the glass master.

Prior to the start of electroforming, while the cathode 15 is being rotated by the motor 4, the jet from the jet nozzle 7 is applied to the glass master for about 1 to 2 minutes, for example, and the jet from the jet nozzle 7 is stopped. , Start electroforming. And
For example, after performing electroforming for 15 to 20 minutes, electroforming is temporarily stopped and the jet flow from the jet nozzle 7 is started again. Next, the jet flow from the jet nozzle 7 is performed for about 1 to 2 minutes, and the electroforming that was interrupted when the jet flow was stopped is restarted. As described above, the step of applying the jet of the electroforming liquid to the glass master and the step of performing electroforming are alternately repeated at a predetermined interval to form an electroformed film having a predetermined film thickness, for example, 300 μm.

As described above, in the electroforming process for producing the stamper, the electrocasting liquid jet is applied to the glass master at a predetermined interval, so that projections or dents are formed in the formed electroformed film. The surface of the electroformed film produced is made smoother by stopping electroforming while the jet flow is being applied to the glass master, and the subsequent back surface in the stamper manufacturing process can be prevented. When polishing is performed, the required time is further shortened and the cost is reduced.

[0039]

As described above, the stamper manufacturing method according to the first aspect of the present invention is used for electroforming the above master in the electroforming tank containing the electroforming liquid prior to the start of the electroforming process. A jet of liquid is applied.

Therefore, before the electroforming process is started, the gas adhering to the master can be removed to prevent the formation of protrusions and dents in the electroformed film formed, and from the start to the end of electroforming. Since the surface roughness of the electroformed film can be improved compared to the case where the jet of the electroforming liquid is continuously applied to the master, the time required for the subsequent back surface polishing of the stamper is shortened, and the manufacturing cost is reduced. The effect that can reduce.

In the stamper manufacturing method according to the second aspect of the present invention, as described above, the jet of the electroforming liquid is intermittently applied to the master in the electroforming tank containing the electroforming liquid. , Electroforming treatment is performed.

Further, as described above, the stamper manufacturing method according to the invention of claim 3 is the method of manufacturing the stamper according to claim 2, wherein an injection nozzle is used to apply a jet of the electroforming liquid to the master. By vertically moving the jet nozzle, the jet port of the jet nozzle is regularly displaced from the master.

Further, as described above, the stamper manufacturing method according to the invention of claim 4 uses the injection nozzle to apply the jet of the electroforming liquid to the master in the method of manufacturing the stamper according to claim 2. By rotating the jet nozzle, the jet port of the jet nozzle is regularly displaced from the master.

Therefore, the gas adhering to the master disk can be efficiently removed, the generation of projections and dents in the electroformed film can be prevented, and in the electroforming step, a jet flow of the electroforming liquid is applied. Instead, the time for performing the electroforming treatment is provided, the surface roughness of the electroformed film is improved, and the time required for polishing the back surface of the stamper can be shortened, so that the manufacturing cost can be reduced.

Further, as described above, the stamper manufacturing method according to the fifth aspect of the present invention includes the step of applying a jet flow of the electroforming liquid to the master in the electroforming tank containing the electroforming liquid. The casting process and the casting process are alternately performed.

Therefore, the gas adhering to the master can be efficiently removed, and the formation of protrusions and dents in the electroformed film can be prevented, and in the step of performing the electroforming treatment, the jet of the electroforming liquid is applied to the master. Since it is possible to form an electroformed film with improved surface roughness, it is possible to shorten the time required for polishing the back surface of the stamper and reduce the manufacturing cost.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a schematic configuration of an electroforming apparatus used in a stamper manufacturing method according to an embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view for explaining a manufacturing process of the stamper.

FIG. 3 is a sectional view of a master holder arranged as a cathode in the electroforming apparatus.

FIG. 4 is a cross-sectional view showing a schematic configuration of an electroforming apparatus used in a stamper manufacturing method according to another embodiment of the present invention.

FIG. 5 is a cross-sectional view showing a schematic configuration of an electroforming apparatus used in a conventional stamper manufacturing method.

[Explanation of symbols]

 2a Concavo-convex pattern (undulation pattern) 3 Electroforming tank 7 Injection nozzle 9 Glass master 13 Stamper 14 Electroforming liquid

Claims (5)

[Claims] 1. A stamper manufacturing method for producing a stamper for replicating a fine relief pattern by subjecting a master having a fine relief pattern formed on a surface thereof to an electroforming process. A method for manufacturing a stamper, characterized in that a jet of an electroforming liquid is applied to the master plate before the start of the electroforming process in an electroforming tank containing the above. 2. A stamper manufacturing method for producing a stamper for replicating a fine relief pattern by subjecting a master having a fine relief pattern formed on its surface to an electroforming process. A method of manufacturing a stamper, which comprises performing an electroforming treatment while intermittently applying a jet flow of an electroforming liquid to the master in an electroforming tank containing the stamper. 3. An injection nozzle is used to apply a jet of electroforming liquid to the master disk, and by vertically moving the spray nozzle, the injection port of the injection nozzle is periodically displaced from the master disk. Item 2. A method for manufacturing a stamper according to item 2. 4. An injection nozzle is used to apply a jet of electroforming liquid to the master disk, and by rotating this injection nozzle, the injection port of the injection nozzle is regularly displaced from the master disk. 2. The method for manufacturing a stamper according to 2. 5. A stamper manufacturing method for producing a stamper to be used for replicating a fine relief pattern by subjecting a master having a fine relief pattern formed on its surface to an electroforming process. A method of manufacturing a stamper, which comprises alternately performing a step of applying a jet flow of an electroforming liquid to the master in an electrocasting tank containing the gas and a step of performing an electroforming treatment.