JP2001283475A - Direct mastering substrate and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To manufacture a direct mastering substrate in which a stamper can be formed by etching through a smaller number of processes than before, in a short time, at low cost and with a high yield, and also to provide an method for manufacturing the stamper using the substrate. SOLUTION: One side of a blank for a stamper is mirror finished while the other side is ground more roughly than the mirror finishing and then, it is machined for the outer diameter of the stamper.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a direct mastering substrate for producing a stamper by etching a stamper substrate, a method for producing the substrate, and a method for producing a stamper using the substrate.

[0002]

2. Description of the Related Art A process for producing a master of an optical disk is called a "mastering" process, and in this process, a master of metal such as nickel called "stamper" is finally produced. The stamper is used as a mold in a later molding step, and the mold produces a large number of copies of the optical disc.

A conventional mastering process will be described with reference to FIG. In FIG. 11A, reference numeral 210 denotes a glass substrate having a mirror-polished surface, on which a positive photoresist is applied to form a positive photoresist film 220. Description of processing and polishing of the glass substrate 210 is omitted.

After a positive type photoresist film is applied to form a positive type photoresist film 220, FIG.
As shown in (1), the laser 10 whose signal has been modulated is squeezed to a submicron size by the recording lens 11 and irradiated to the positive type photoresist film 220 for exposure.

Next, as shown in FIG. 11C, a developing solution is applied from a nozzle 230 onto the positive photoresist film 220 on the glass substrate 210, and the exposed portion of the positive photoresist film 220 is removed by etching. Then, fine depressions 240,..., 240 called pits are formed on the photoresist film 220.

Thereafter, as shown in FIG. 11D, the glass substrate 210 is heated by baking to stabilize the positive photoresist film 220.

Next, as shown in FIG. 11E, a metal conductive film 250 is formed on the photoresist film 220 by sputtering or the like.

Thereafter, as shown in FIG. 11F, nickel plating is performed using the conductive film 250 as an electrode to form a thick nickel film 260 having a thickness of about 0.3 mm. FIG.
As shown in FIG. 1 (g), replicas of the pits 240,..., 240 on the photoresist film 220 are formed on the thick film 260. The nickel thick film 260 was peeled off from the glass substrate 210, the back surface of the nickel thick film 260 was polished, and the inner and outer diameters were punched to fit a molding machine for molding an optical disk, thereby completing a stamper.

[0009]

However, as described above, the conventional mastering process involves the use of the glass substrate 21.
Pits 240 on the photoresist film 220 on
, 240 are formed first, and the pits 240,.
0 was transferred to the nickel thick film 260 by electroforming to form a stamper. Therefore, if a defect occurs in the process of forming a stamper, the process must be restarted from the beginning, and the yield of the entire process has been reduced. Also,
The number of steps was large, and the probability of occurrence of defects was large. Also,
They needed a lot of equipment and needed a lot of money for initial investment.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above-mentioned problems, and it is an object of the present invention to provide a direct mastering method in which a stamper can be manufactured by etching with a reduced number of steps in a short time, at low cost, and with a high yield. An object of the present invention is to provide a substrate, a method of manufacturing the same, and a method of manufacturing a stamper using the substrate.

[0011]

In order to achieve the above object, the present invention is configured as follows.

According to a first aspect of the present invention, in a method of manufacturing a substrate for direct mastering, in which signal projections are formed on a substrate by etching to form a stamper, one surface of the blank material of the stamper is mirror-polished and the other surface is mirror-polished. A method for manufacturing a substrate for direct mastering, characterized in that the substrate is processed to an outer diameter of the stamper after being polished more coarsely.

According to a second aspect of the present invention, after the blank material of the stamper is processed to the outer diameter of the stamper, sputtering, ion plating, vacuum deposition, and the like are performed on the mirror-polished surface of the blank material. A method of manufacturing a substrate for direct mastering according to the first aspect, wherein the metal layer is formed by any one of electroforming and electroless plating.

According to a third aspect of the present invention, the substrate comprises:
The substrate for direct mastering according to the first or second aspect, wherein the substrate is composed of a material mainly containing at least one of nickel, chromium, aluminum, titanium, cobalt, iron, molybdenum, tungsten, boron, copper, and niobium. And a method for producing the same.

According to a fourth aspect of the present invention, the substrate comprises:
A method for manufacturing a substrate for direct mastering according to the first or second aspect, wherein the substrate is made of Si or any one of Si compounds of SiO ₂ or SiC.

According to a fifth aspect of the present invention, there is provided the method of manufacturing a substrate for direct mastering according to the first or second aspect, wherein the substrate is made of glass.

According to a sixth aspect of the present invention, the substrate comprises:
The first, which is composed of a material mainly composed of carbon
Alternatively, there is provided a method of manufacturing a substrate for direct mastering according to the second aspect.

According to a seventh aspect of the present invention, the metal layer formed on the mirror-polished surface includes titanium nitride, titanium oxide, tantalum, tungsten, chromium, molybdenum, cobalt, boron, niobium, nickel A method for manufacturing a substrate for direct mastering according to the second aspect, wherein the substrate is made of phosphorus, nickel boron, or nickel cobalt.

According to an eighth aspect of the present invention, there is provided the method of manufacturing a substrate for direct mastering according to the second or seventh aspect, wherein the thickness of the metal layer formed on the mirror-polished surface is equal to the etching depth. I do.

According to a ninth aspect of the present invention, there is provided a direct mastering substrate manufactured by the method for manufacturing a direct mastering substrate according to any one of the first to eighth aspects.

According to a tenth aspect of the present invention, a negative type photoresist is applied on the substrate according to the ninth aspect to form a photoresist film, and a signal is applied to the photoresist film by a laser beam. Exposure and recording by irradiation, heat treatment of the substrate on which the laser beam is irradiated and the signal is recorded, causing rearrangement of polymer chains in the exposed portion of the photoresist film, by dry development,
The unexposed portion of the resist film of the substrate is removed, only the exposed portion of the resist film is left as a protrusion, dry etching is performed using the protrusion as a mask, and the protrusion after etching is removed by ashing to produce a stamper. A method of manufacturing a stamper is provided.

According to an eleventh aspect of the present invention, there is provided a substrate for an optical disk stamper used for direct mastering of forming a signal projection on the substrate by etching to form a stamper. Provided is a substrate for an optical disk stamper in which a resist is applied to the above-processed substrate to form a resist film for signal recording.

According to a twelfth aspect of the present invention, a resist is applied to the substrate according to the ninth aspect, which is processed so as to fit a mold of a molding machine for molding an optical disk, and a resist film for signal recording is formed. An optical disk stamper substrate formed is provided.

According to a thirteenth aspect of the present invention, there is provided the optical disc stamper substrate according to the eleventh or twelfth aspect, wherein the back surface of the substrate has a center line average roughness of about 0.1 μm. .

According to a fourteenth aspect of the present invention, any one of the eleventh to thirteenth aspects, wherein the inner or outer diameter or the outer diameter is machined so as to be attached to the mold of the molding machine for molding an optical disk.
According to another aspect of the present invention, there is provided an optical disc stamper substrate.

According to a fifteenth aspect of the present invention, the substrate has a two-layer structure of a base layer and an etching layer disposed on the base layer and having a thickness substantially equal to the height of the signal protrusion. The substrate for an optical disk stamper according to any one of the above-described aspects, is provided.

According to a sixteenth aspect of the present invention, the resist is any one of the first to fifteenth, wherein the resist is a negative resist.
According to another aspect of the present invention, there is provided an optical disc stamper substrate.

According to a seventeenth aspect of the present invention, there is provided the substrate for an optical disk stamper according to any one of the eleventh to sixteenth aspects, wherein the resist is a resist which can be dry-developed.

According to an eighteenth aspect of the present invention, the eleventh to the first
7. A signal is exposed and recorded on the resist film of the optical disc stamper substrate according to any one of aspects 7 to 7 by irradiating a laser beam, and the substrate on which the signal is recorded by irradiating the laser beam is heated. Then, to cause rearrangement of the polymer chains of the exposed portion of the resist film, by dry development, remove the unexposed portion of the resist film of the substrate, leaving only the exposed portion of the resist film as a protrusion, Provided is a method for manufacturing a stamper in which dry etching is performed using a projection as a mask, and the projection after etching is removed by ashing to manufacture a stamper.

[0030]

Embodiments of the present invention will be described below in detail with reference to the drawings.

(First Embodiment) In a method of manufacturing a substrate for direct mastering according to a first embodiment of the present invention, a stamper substrate to be finally processed into a stamper is prepared without using a glass substrate. Forming signal irregularities such as signal protrusions by etching directly on the substrate,
Finally, the stamper is completed.

That is, first, a blank material for a stamper substrate is prepared, and one surface of the blank material is mirror-polished, and the other surface of the blank material is polished more than the mirror surface. When the blank material is made of metal, after polishing, annealing is performed at a temperature lower than the recrystallization temperature to remove distortion,
Then, it is processed to the outer diameter of the stamper to complete the substrate.

In a method of manufacturing a substrate for direct mastering according to a second embodiment of the present invention described later, a metal material is laminated by sputtering or the like on the mirror-polished surface in the first embodiment. Becomes

Hereinafter, the first embodiment will be described in detail.

First, the steps of a method for manufacturing a substrate for direct mastering according to the first embodiment of the present invention are shown in FIG.

In FIG. 1A, reference numeral 1 denotes a blank material for a stamper substrate. The blank 1 is finished to have a thickness and an outer shape that are larger than the size finally required as a stamper. As an example, a typical stamper size is 138 mm in diameter and 0.3 mm in thickness. The blank 1 is processed to a slightly larger suitable size. When the blank material 1 is metal, it may be punched from a coil-shaped hoop material. It is effective to perform pressure annealing at a temperature slightly lower than the recrystallization temperature in order to remove the processing strain from the metal blank material 1 and obtain a flat substrate having a flatness of 20 μm or less. In the example of the first embodiment in which the blank material 1 is made of a nickel plate, the blank material 1 is sandwiched between flat spacers, and pressure is applied to 270 ° C. to 3 ° C.
Pressure annealing is performed by heating to a temperature of 50 ° C.

FIG. 1B schematically shows the next step of polishing the surface of the blank 1.
The purpose of this step is to finally finish the stamper to the required thickness and to finish the surface to the required surface accuracy.

In a conventional mastering method, a stamper is removed from a resist surface applied to a mirror-polished glass substrate by electroforming. Therefore, the mirror state is also transferred to the stamper surface. On the other hand, the back surface is polished with a polishing tape or the like after electroforming. The back surface is not a mirror surface but has a surface roughness Ra
It is about 0.05 to 0.1 μm. Ra is the center line average roughness. The back surface of the stamper is attached to the mold surface of a molding machine for molding an optical disk. The stamper is a nickel plate having a thickness of about 0.3 mm. for that reason,
When the high-temperature and high-pressure resin is injected from the center of the mold, the stamper is pushed by the thermal expansion and the pressure of the resin, and extends and spreads to the outer periphery. Although the elongation is a very small amount of about 10 μm, there is a relative displacement between the mold surface and the stamper.
Without this relative movement, the flow of the resin will not be smooth, causing distortion inside. If the back surface of the stamper is a mirror surface, the stamper is in close contact with the mold surface, which is also a mirror surface, and this relative movement hardly occurs. For the above reasons, it is said that the back surface of the stamper should be polished more coarsely than the mirror surface. Less than,
The polishing step will be described with reference to FIG.

The blank 1 is attracted to the polishing head 6, and the blank 1 is pressed against the polishing pad 3 on the rotating polishing table 2 by the polishing head 6. A slurry 5 containing an abrasive is discharged from a nozzle 4 onto the polishing pad 3, enters between the polishing pad 3 and the blank 1, and the surface of the blank 1 is polished. The polishing head 6 also rotates, and the blank 1 moves on the polishing pad 3 while rotating and revolving, and the entire surface of the blank 1 is polished uniformly. One side of the blank material 1 finally becomes a surface on which a signal of the stamper is formed, and therefore it is necessary to finish it to a mirror surface. On the other hand, the back surface of the stamper does not need to be a mirror surface for the above-described reason.
Polishing of about 0.1 μm is performed.

First, Ra0.05 was applied to both sides.
Polishing is performed to about 0.1 μm, and then only one side is switched to a slurry in which abrasive particles are made finer, and the surface is finished to a mirror surface. FIG. 1B shows an apparatus for single-side polishing, but an apparatus for polishing both sides simultaneously for the first polishing may be used.

FIGS. 2 and 7 schematically show an apparatus for simultaneous double-side polishing. This apparatus is mainly used when the blank material 1 is ceramic or the like and the stamper thickness is 0.7 mm or more. In FIG. 2, 1,1 ′ is a blank material. Reference numerals 50 and 51 denote an upper surface plate and a lower surface plate, respectively. Polishing pads 52 and 53 are attached to respective opposing surfaces, and pressurize the blank materials 1 and 1 'therebetween. A slurry of an abrasive is supplied between the blank materials 1 and 1 'and the polishing pads 52 and 53, as in FIG. The blanks 1 and 1 'are respectively polished by polishing pads 52 and 53 by carriers 54 and 54'.
Position restrictions are set so that they do not protrude. Reference numeral 55 denotes an internal gear, which is inwardly geared to oppose the carriers 54 and 54 ', and which includes the upper and lower platens 50 and 51 and the carriers 54 and 54'.
It is configured to encompass the entire 54 '. Gears are provided on the outer periphery of the carriers 54 and 54 ′, and are engaged with the internal gear 55 and the sun gear 57 of the rotating shaft 56. The rotation of the sun gear 57 and the internal gear 55 causes the carriers 54 and 54 ′ to rotate.
Revolves, and revolves due to the difference in peripheral speed between the sun gear 57 and the internal gear 55. By this operation, the blank materials 1, 1 'also rotate and revolve between the polishing pads 52, 53, and both surfaces are polished. Although only two carriers 54 and 54 'are shown in FIG. 2, up to four carriers are possible as shown in FIG.

After the polishing, next, as shown in FIG.
In the case where distortion due to polishing remains mainly in the metal blank material 1, 1 ', etc., annealing performed to remove the processing distortion is schematically shown.

Next, as shown in FIG. 1D, a state in which the inner and outer diameters of the blank materials 1 and 1 'are machined to a size suitable for a mold of a molding machine for molding an optical disk as a stamper is shown. The substrate 7 is thus completed.

After that, physical signal tracks are formed on the substrate 7, and before the stamper is completed, if the inner and outer diameters of the substrate 7 are machined to the stamper size so as to fit the mold, the post-process will be performed. Is reduced, and the yield can be increased. However, in order to minimize the misalignment between the center of the recording track and the inner diameter of the stamper, the center of the track of the substrate 7 may be obtained after forming the signal track by etching, and the inner diameter of the substrate 7 may be processed based on the center. In this case, only the outer diameter of the substrate 7 is processed in FIG. Also, the outer diameter of the substrate 7 may be processed simultaneously with the inner diameter of the substrate 7 after signal tracks are formed.
Conversely, before polishing the surface of the substrate 7, the inner and outer diameters of the substrate 7 may be machined to a stamper size. In this case, it is necessary to take care that the edge of the substrate 7 does not drop when the substrate 7 is polished.

As the blank materials 1 and 1 ', nickel,
Chrome, aluminum, titanium, cobalt, iron, molybdenum,
A material mainly containing at least one of tungsten, boron, copper, and niobium can be used. If the thickness of the completed substrate 7 is made the same as that of a nickel plate produced by conventional electroforming, a molding machine for molding a conventional optical disk can be used without changing the mold.

According to another modification of the first embodiment, the blank materials 1 and 1 ′ are made of Si, SiO ₂ , S
Any of Si compounds such as iC can be used.
These are excellent in workability during polishing and etching, and are relatively easily available because they are widely used in the semiconductor field.

In still another modification of the first embodiment, glass can be used as the blank materials 1 and 1 '. Considering the processability of etching, quartz glass is preferred.

Further, in still another modification of the first embodiment, a material containing carbon as a main component can be used as the blank materials 1 and 1 '. A material obtained by sintering carbon powder into a plate shape can be used.

Next, in the first embodiment, the substrate 7
A process of forming a stamper by processing is described with reference to FIG.

The outline of the process of forming a stamper from a substrate is as follows.

First, a negative type photoresist is applied on the substrate 7. Then, after the baking process,
The substrate 7 is rotated, and the surface of the substrate 7 is irradiated with a laser whose signal is modulated and stopped down by a recording lens to expose the surface. Thereafter, development, etching, and resist removal are performed by a dry process or the like after a heat treatment, and signal irregularities, for example, signal projections are formed on the surface of the substrate 7 to manufacture a stamper of the optical disk.

Hereinafter, this will be described in detail.

FIG. 3A shows a state in which a negative resist is applied to the substrate 7 to form a negative resist film 9.

In the next FIG. 3B, a signal is recorded by a laser beam recorder. Although not shown here, the laser beam recorder modulates the laser beam with a desired signal, irradiates the laser beam along the radial direction of the substrate and exposes the laser beam, and rotates the substrate at a desired rotational speed. It has a rotating device 201. In FIG. 3B,
As the optical device 200, the signal-modulated laser beam 1
0, a recording lens 11 for focusing a laser beam 10 to a submicron size and exposing a resist film 9 on a rotating substrate 7 is shown.

Next, as shown in FIG. 3C, the substrate 7 on which the laser beam is irradiated and exposed and the signal is recorded is heated in an oven or the like. FIG. 3C shows the substrate 7 which has been annealed by the heat treatment. In this heat treatment step, 130 to 15
A heat treatment at 0 ° C. is performed for about 30 minutes. By this heat treatment, rearrangement of the polymer chains in the exposed portions of the resist film 9 of the substrate 7 occurs, and the etching resistance of the resist film 9 can be improved.

Next, FIG. 3D shows the substrate 7 after the subsequent dry development. Resist film 9 on substrate 7
Are removed, and only the exposed portions of the resist film 9 remain as protrusions 12,... Dry development is performed by oxygen plasma. As one of the negative resist films 9 which can be subjected to such dry development, a mixture of a polymethylisopropenyl ketone (PMIPK) and a bisazide compound is known.

In this example, dry development is used, but the present invention is not limited to this, and can be applied to conventional wet development.

Next, dry etching is performed using the projections 12,..., 12 as a mask. FIG. 3E shows the substrate 7 after the etching. Reference numeral 12 'denotes a projection 12 after etching, and reference numeral 13 denotes a signal projection formed on the substrate 7. The most suitable gas to be used for the etching is selected according to the substrate 7, but generally, CF ₄ , NF ₃ , BCl ₃
—Cl _{3 ,} Cl _{3 ,} or CCl ₄ is used.

Next, FIG. 3F shows a state after the projections 12 ',..., 12' after the etching are removed by ashing, and a so-called stamper is completed. Ashing is performed by using the oxygen radicals of the oxygen plasma to form projections 1.
This is a step of decomposing 2 ′,..., 12 ′ into CO ₂ and H ₂ O. The stamper completed in this manner is mounted on a mold of an optical disc molding machine for molding an optical disc, and a large amount of copies of the optical disc can be produced using the stamper and the mold.

As described above, in the method of manufacturing a substrate for direct mastering according to the first embodiment, a substrate that will ultimately become a stamper is prepared without using a glass substrate, and signal irregularities are directly formed thereon by etching. Forming signal projections to complete the stamper, without using wet processing, with a small number of steps, in a short time and at low cost.
A stamper can be manufactured with a high yield. Further, the development, etching, and resist removal steps can all be performed by a dry method in the same chamber while changing only the reaction gas. As a result, handling between processes can be eliminated, and the opportunity for foreign matter to adhere to the substrate or the stamper can be eliminated.

(Second Embodiment) FIG. 4 shows a substrate for direct mastering according to a second embodiment of the present invention. This is obtained by manufacturing the substrate 7 in the direct mastering substrate manufacturing process of the first embodiment shown in FIG. 1 and then adding the second layer 8 to the mirror-polished surface of the manufactured substrate 7. It is. As a material of the second layer 8, titanium nitride, titanium oxide, tantalum, tungsten, chromium, molybdenum, cobalt, boron, niobium, nickel phosphorus, nickel boron, nickel cobalt, or the like can be used. The purpose of providing the second layer 8 is to improve workability in etching. As described above, since the substrate 7 itself is cut out from the blank materials 1 and 1 'and the surface is polished, a material having good workability is advantageous. In addition, economically optimal materials are selected from the viewpoint of cost. On the other hand, since signal irregularities, for example, signal projections are formed by etching on the surface layer of the substrate 7, a material having good etching properties is desired.

The height of the signal unevenness, for example, the signal projection, is λ / (4n), where λ is the laser wavelength for reproducing (recording) the optical disk, and n is the refractive index of the optical disk after being molded with a synthetic resin such as polycarbonate. OK, roughly 100-1
The value is about 50 nm. Therefore, if the second layer 8 has a thickness of 1 micron, a signal projection can be sufficiently formed. The whole is 0.3m
m or more, so mechanical as a stamper,
In terms of thermodynamics, it can be considered that the characteristics are almost the same as those of the substrate 7.

When the substrate 7 is made of nickel or a nickel-based alloy and such a substrate 7 is provided with the second layer 8, it can be molded under the same molding conditions as a conventional nickel stamper.

The second layer 8 is formed by ion plating,
It can be firmly formed on the substrate 7 by sputtering, vacuum deposition, electroforming, electroless plating, or the like. In this case, the hardness is high and the stamper can be sufficiently used.

Next, FIG. 5 shows a stamper manufacturing process using the substrate 7 with the second layer 8 manufactured in the second embodiment of FIG.

FIG. 5A shows a state where a negative resist is applied on the second layer 8 of the substrate 7 of FIG. 4 to form a negative resist film 14. This resist film 14 is the same as the resist film 9 in FIG.

Next, FIG. 5B shows a state where a signal is recorded by a laser beam recorder. The laser beam recorder is not shown here as in FIG. 3, but the laser beam is modulated by a desired signal. The optical device 200 includes an optical device 200 that irradiates a laser beam along a radial direction of the substrate 7 for exposure, and a rotation device 201 that rotates the substrate 7 at a desired rotation speed. In FIG. 5B, as the rotation device 201,
Signal-modulated laser beam 10 and laser beam 10
The recording lens 11 exposes the resist film 14 on the rotating second layer 8 by irradiating the resist film 14 with a laser beam.

Next, FIG. 5C shows a state in which the substrate 7 having the resist film 14 on which the laser beam is irradiated and exposed to light and on which the signal is recorded is subjected to a heat treatment in an oven or the like to complete the annealing. Is shown. In this step,
A heat treatment at 130 to 150 ° C. is performed on the substrate 7 for about 30 minutes. This process causes rearrangement of the polymer chains in the exposed portions of the resist film 14, thereby improving the etching resistance of the resist film 14.

Next, FIG. 5D shows the substrate 7 after the subsequent dry development. The unexposed portions of the resist film 14 are removed, and only the exposed portions of the resist film 14 remain as protrusions 15,. Also in this example, the development is dry development, but the present invention is not limited to this and can be applied to conventional wet development.

Then, dry etching is performed using the projections 15,..., 15 as a mask. FIG. 5E shows the substrate 7 after the etching. 15 'is a projection 1 after etching.
Reference numerals 5 and 16 denote signal protrusions formed on the second layer 8. The most suitable gas to be used for the etching is selected according to the substrate 7, but generally, CF ₄ , NF ₃ , and BCl _{3 are used.}
—Cl ₃ or CCl ₄ is used.

FIG. 5F shows a state after the resists 15 ',..., 15' are removed by ashing, and a so-called stamper is completed. The stamper completed in this manner is mounted on a mold of an optical disc molding machine for molding an optical disc, and a large amount of copies of the optical disc can be produced using the stamper and the mold.

In the case of the second embodiment shown in FIGS. 4 and 5, if the thickness of the second layer 8 provided on the surface is made equal to the desired etching depth, the end point of the etching can be easily detected. Can accurately control the height of the signal pit.

The detection of the end point of the etching will be described below with reference to FIG.

FIG. 6 is a schematic view of a parallel plate type etching apparatus for reactive ion etching.

In FIG. 6, reference numeral 30 denotes a chamber which can be used as various processing chambers, 31 denotes an upper electrode in the chamber 30,
Reference numeral 2 denotes a lower electrode which is disposed in the chamber 30 so as to face the upper electrode 31 and holds the substrate 7 of FIG. Reference numeral 34 denotes a matching device, and reference numeral 35 denotes a high-frequency power supply that applies a high-frequency voltage to the lower electrode 32 via the matching device 34. 36 is an exhaust pump for exhausting the inside of the chamber 30, and 37 is a chamber 30 to which pipes 39, 40 and 41 for reaction gas are connected.
A reaction gas supply pipe for supplying a reaction gas into the inside;
Are pipes 39, 40 connected to the reaction gas supply pipe 37,
Reference numerals 41 denote valves for adjusting the supply flow rates of the reaction gases respectively supplied. The reactive gases supplied through the pipes 39, 40, and 41 are three types of gases for dry development, etching, and ashing. Various reaction gases are connected to a reaction gas supply pipe 37 from a supply tank (not shown) via pipes 39, 40, and 41 via flow rate control valves 38, respectively.
42 is an optical fiber for detecting the etching end point of the substrate 7, 43 is an etching end point detecting device, 44 is an etching for stopping application of a high frequency voltage to the lower electrode 32 by the high frequency power supply 35 when the etching end point is detected by the etching end point detecting device 43. It is a control device. The end point of the etching of the substrate 7 is performed by monitoring the light emission state of the plasma with 42 optical fibers. The emission spectrum of plasma is due to radicals and ions such as an etching gas, its decomposition product, and a reaction product. That is, the etching of the second layer 8 of the substrate 7 proceeds, the substrate 7 appears, and when the etching of the substrate 7 starts, the emission spectrum of the plasma changes. This change is detected by the etching end point detecting device 43, and the control device 44 is instructed to stop the etching. As a result, the controller 44 stops the application of the high-frequency voltage to the lower electrode 32 by the high-frequency power supply 35, and stops the etching operation.

According to the second embodiment, the etching of the second layer 8 proceeds, the substrate 7 appears, and when the etching of the substrate 7 starts, a change occurs in the emission spectrum of the plasma.
Since the change is detected by the etching end point detecting device 43 and the etching operation is stopped by the control device 44, the amount of etching on the substrate 7 can be managed more accurately with the accuracy of the film thickness of the second layer 8. it can. That is, in general, the control of the film thickness at the time of film deposition can be more accurately controlled than the control of the etching amount.

Although the above description is about dry etching,
The present invention is also applicable to wet etching.

(Third Embodiment) FIG. 8 shows a stamper substrate with a resist film used in direct mastering which forms a signal protrusion on a substrate by etching to form a stamper according to a third embodiment of the present invention, and A mastering step using a stamper substrate in a stamper manufacturing method using the same will be described. The present invention will be described with reference to FIG.

First, the purpose of the third embodiment will be described.

As described above, the mastering process includes many chemical processing steps such as development and electroforming, starting from polishing and cleaning of the glass substrate. Therefore, a manufacturer of the stamper needs many equipments and associated pure water equipment and waste liquid treatment facilities. Further, since many man-hours are required, the probability of occurrence of a defect due to adhesion of dust or the like increases.

Accordingly, an object of the third embodiment is to solve the above-mentioned problem and to provide a stamper substrate which can be used in a system capable of manufacturing a stamper with less equipment and with a higher yield than in the past. It is possible to produce and sell a stamper substrate which can be manufactured in a short time, at low cost and with high yield with a smaller number of steps, and which can be applied to a new mastering method, and can provide it to a stamper manufacturer.

FIG. 8A shows an optical disk stamper substrate 107 used in direct mastering in which a signal projection is formed on a substrate by etching to form a stamper.
Shows a stamper substrate with a resist film in which a negative resist is applied to form a negative resist film 109 for signal recording. The thickness of the substrate 107 has already been processed so that it can be attached to a mold of a molding machine for molding an optical disk. In addition, the surface of the substrate 107, that is, the surface on which the resist is applied is polished to a mirror surface. The back surface of the substrate 107 has a center line average roughness of 0.1 μm.
It is processed to the front and rear roughness by polishing or the like. The back surface roughness is finished to an optimum roughness in consideration of contact with a mold of a molding machine for molding an optical disk.

Next, a signal is recorded on the substrate 107 by a laser beam recorder. Although not shown here, a laser beam recorder modulates the laser beam with a desired signal and irradiates the laser beam along the radial direction of the substrate 107 to expose the substrate 107 and the substrate 107 at a desired rotation speed. It has a rotating device 201 for rotating.

In FIG. 8B, as the optical device 200,
The laser beam 10 modulated with the signal and the resist beam 1 on the rotating substrate 107 are squeezed to a submicron size.
Recording lens 1 for exposing by exposing laser beam 09
1 is shown.

FIG. 8C shows a step of heating the substrate 107 on which the laser beam has been irradiated and exposed and on which the signal has been recorded, in an oven or the like. For chemically amplified resists, baking after exposure, so-called post-exposure baking, is necessary. However, depending on the type of resist, baking after exposure is unnecessary, and in this case, this step can be omitted.

FIG. 8D shows the substrate 107 after development. The unexposed portions of the resist film 109 on the substrate 107 are removed, and only the exposed portions of the resist film 109 are projected.
.., 112 remain. Development includes wet development and dry development, each of which is determined by the type of resist used. The third embodiment can be applied to either resist. It is known that a resist capable of dry development is prepared by mixing a bisazide compound with polymethylisopropenyl ketone (PMIPK). This resist is subjected to a heat treatment at 130 to 150 ° C. for about 30 minutes after exposure.
This treatment causes rearrangement of the polymer chains, improves the etching resistance of the resist, and enables development by oxygen plasma. In addition, there is a resist that forms a silicon atmosphere on the surface after exposure, forms a silicon compound in the exposed portion, obtains resistance to oxygen plasma in the exposed portion, and enables dry development.

The resist used as an example is shown in FIG.
The unexposed portion of the substrate 107 shown in FIG. 4D is removed, and only the exposed portion remains as protrusions 112,..., 112. The resist may not be a negative resist from the beginning, but may be a positive resist, or may be a resist that acts as a negative tone by a treatment such as an image reversal method after exposure.

Next, the projections 112,...
Then, dry etching is performed. Fig. 8 (e) shows the etch
The substrate 107 after the etching is shown. 112 'after etching
The protrusions 112 and 113 are signal protrusions formed on the substrate 107.
It represents the beginning. The gas used for etching is the substrate 10
7, the most suitable one is selected.
F _Four, NF_Three, BCl_Three-Cl_Three, Cl_Three, CCl_FourAnd so on
Can be.

FIG. 8F shows a state after the projections 112 ',..., 112' made of resist have been removed by ashing, and a stamper as a so-called master has been completed. Ashing is a process in which the projections 112 ′,..., 112 ′ made of resist are decomposed into CO ₂ and H ₂ O by oxygen radicals of oxygen plasma.

Thereafter, the substrate 107 is processed into inner and outer diameters so as to be mounted on a mold of a molding machine for molding an optical disk, thereby completing a stamper. The stamper completed in this manner is mounted on a mold of an optical disc molding machine for molding an optical disc, and a large amount of copies of the optical disc can be produced using the stamper and the mold.

In the process using the stamper substrate 107 according to the third embodiment, there is no polishing and cleaning steps for the glass disk.
It is possible to prevent a decrease in yield due to adhesion of foreign matter on the substrate 107. Stamper manufacturers avoid the risk of erroneously using rejects with surface defects by using stamped substrates with resist films that are pre-coated with resist and inspected for surface defects. be able to.

Further, defects such as dry spots are likely to occur after removing the plating solution by stamper cleaning after electroforming. However, the third embodiment does not have any electroforming process, and thus does not cause any defect.

Further, in the dry developing process, there is no wet process, so that defects such as dry spots do not occur.

(Fourth Embodiment) FIG. 9 shows a stamper substrate with a resist film and a method of manufacturing a stamper using the same according to a fourth embodiment of the present invention. In FIG. 9A, reference numeral 117 denotes a substrate for a stamper with a resist film similar to that of FIG. 8, except that the stamper is already processed into a stamper size suitable for a mold of a molding machine for molding an optical disk. is there. The substrate manufactured in the direct mastering substrate manufacturing process of the first embodiment shown in FIG. 1 may be used, and a substrate finished to the same specification as the substrate shown in FIG. 8 may be used. 119 is a negative resist. 9 (b) and 9 (c) are (b) of FIG.
This is the same exposure and heat treatment as in (c). FIG. 9D shows the substrate 117 after development, in which protrusions 122,.
122 remains. FIG. 9E shows a substrate 117 after dry etching, in which a projection 122 made of a resist serving as a mask remains as 122 ′. 123 is a signal projection formed on the substrate 117. FIG. 9F shows the substrate 117 after the plasma ashing, which has already been processed to the stamper size, and is thus attached to a molding machine for molding an optical disk. The processing in FIG. 9A may be only the outer diameter. In that case, only the inner diameter will be processed later.
In that method, the signal projection 12 is etched on the substrate 117.
After the formation of the track 3, the inner diameter can be opened with reference to the track center.

If there is only one place to finish the substrate 117 in the state of FIG. 9A, other optical disk factories that perform the processing after that need to manufacture a stamper if they have the equipment after FIG. 9B. Can be done.

In the third and fourth embodiments, the material of the substrates 107 and 117 must be able to withstand the injection pressure of the high-temperature resin during molding. As the substrates 107 and 117, nickel, aluminum, chromium, titanium, cobalt, molybdenum, tungsten,
Materials containing at least one of boron, tantalum, iron, copper, and the like as a main component can be used and mass-produced at low cost. Since these metal substrates can be easily manufactured to a thickness of about 0.3 mm of a nickel stamper currently used (that is, manufactured by conventional electroforming),
The completed stamper can be used as it is for the mold of the current molding machine. Many of these have thermal conductivity close to that of a conventional nickel stamper and can be molded under the same molding conditions. Therefore, it can be easily replaced with a current stamper.

The substrates 107 and 117 may be formed of silicon carbide (SiC) or a silicon compound such as SiC. These have excellent workability in etching and are relatively easily available because they are widely used in the semiconductor field. Since these silicon substrates are thicker than the current nickel stampers, it is necessary to adjust them by inserting a spacer in a mold.

The substrates 107 and 117 may be composed mainly of carbon. For example, a material obtained by sintering carbon powder into a plate shape can be used.

The substrates 107 and 117 may be formed of quartz glass.

(Fifth Embodiment) FIG. 10 shows a stamper substrate with a resist film and a method of manufacturing a stamper using the same according to a fifth embodiment of the present invention.

In FIG. 10A, 21a is a base layer of the substrate 21, and 21b is an etching layer formed on the base layer 21a. FIG. 10A shows a case where a negative type resist is applied on an etching layer 21b of an optical disk stamper substrate 21 used in a direct mastering process in which a signal projection is formed on a substrate by etching to form a stamper. 5 shows a state in which the negative resist film 22 is formed. This resist film 22 is shown in FIGS.
Are the same as the resist films 9 and 109 in FIG. The base layer 21a can also be constituted by the substrate used in the third embodiment or the fourth embodiment. Further, in the fifth embodiment, similarly to the fourth embodiment, the substrate manufactured by the direct mastering substrate manufacturing process of the first embodiment shown in FIG. 2nd spec.
An etching layer may be added as a layer.

Here, the thickness of the etching layer 21b is adjusted to the height of the signal projection 26 to be finally formed. Assuming that the refractive index of the molded synthetic resin optical disk is n and the wavelength of the reproducing laser is λ, the height of the signal projection is λ / (4
n) is generally used. This etching layer 21b
Suitable materials are titanium nitride, titanium oxide, tantalum, tungsten, chromium, molybdenum, cobalt, boron, nickel phosphorus, nickel boron, nickel cobalt and the like. These materials can be firmly formed on nickel by ion plating, sputtering, vacuum deposition, electroforming or electroless plating. The hardness is also hard enough to withstand use as a stamper. FIGS. 10 (b), (c), and (d) are the same as FIGS. 8 and 9, (b), (c), and (d), respectively, showing signal exposure by laser irradiation, and subsequent heat treatment and development, respectively. ing.

That is, FIG. 10B shows a state in which a signal is recorded by a laser beam recorder. A laser beam recorder is not shown here as in FIGS. 8 and 9, but the laser beam is converted to a desired signal. The optical device 200 includes an optical device 200 that performs modulation and irradiates a laser beam along a radial direction of the substrate 21 for exposure, and a rotation device 201 that rotates the substrate 21 at a desired number of rotations. In FIG. 10B, the rotating device 201 is used as the laser beam 10 having undergone signal modulation.
And squeezing the laser beam 10 to a submicron size,
The recording lens 11 for irradiating the resist film 22 on the rotating etching layer 21b with a laser beam to expose the resist film 22 is shown.

Next, FIG. 10C shows the resist film 22 on which a signal is recorded by being irradiated with the laser beam and exposed.
This shows a state in which the substrate 21 having heat treatment is heated in an oven or the like, and the annealing is completed. In this step, for example, a heat treatment of 130 to 150 ° C.
Perform for about 0 minutes. By this processing, rearrangement of the polymer chains in the exposed portions of the resist film 22 is caused, and the etching resistance of the resist film 22 can be improved.

In FIG. 10D, reference numeral 25 denotes a resist projection of an exposed portion remaining on the etching layer 21b after development. The unexposed portions of the resist film 22 are removed, and only the exposed portions of the resist film 22 remain as protrusions 25,. Also in this example, the development is dry development, but the fifth embodiment is not limited to this, and can be applied to conventional wet development.

Next, dry etching is performed using the projections 25,..., 25 as a mask. The most suitable gas for etching is selected according to the substrate 21. Generally, CF ₄ , NF ₃ , BCl ₃ —Cl ₃ , or CCl
₄ etc. are used. FIG. 10E shows the substrate 21 after the dry etching, 25 ′ the resist protrusion after the etching,
Reference numeral 26 denotes a signal protrusion formed on the etching layer 21b. Here, the height of the signal protrusion 26 corresponds to the thickness of the etching layer 21b.

FIG. 10 (f) shows the signal projections 26, on the etching layer 21b on the base layer 21a on the substrate 21 after the resists 25 ',..., 25' are removed by ashing.
, 26 are formed masters. The stamper is completed by processing the inner and outer diameters to match the mold.
Further, as described in the fourth embodiment of FIG. 9, the fifth embodiment may also be formed into a stamper size from the beginning. The stamper thus completed is attached to a mold of an optical disk molding machine for molding an optical disk,
The stamper and the mold can be used to produce a large number of optical disk copies.

In the fifth embodiment, the thickness of the etching layer 21b as the second layer is adjusted to the desired height of the signal projection 26 in order to detect the end point in the etching with high accuracy.

Regarding the detection of the end point of the etching, the same operation may be performed by the same apparatus as that described with reference to FIG.

That is, in the parallel plate type etching apparatus for reactive ion etching shown in FIG.
The zero substrate 21 is arranged on the lower electrode 32 at the position of the substrate indicated by 7 in FIG. The end point of the etching of the substrate 21 is determined by changing the light emitting state of the plasma
Monitoring is performed in step 2. The emission spectrum of plasma is due to radicals and ions such as an etching gas, its decomposition product, and a reaction product. That is, in the etching step of FIG. 10, the etching of the etching layer 21b, which is the second layer of the substrate 21, proceeds, and the substrate 21 appears. When the etching of the substrate 21 starts, the emission spectrum of the plasma changes. This change is detected by the etching end point detecting device 4.
In step 3, the controller 44 is instructed to stop etching. As a result, the high frequency power supply 35
Then, the application of the high-frequency voltage to the lower electrode 32 is stopped, and the etching operation is stopped.

According to the fifth embodiment, the etching of the etching layer 21b, which is the second layer, proceeds, and the substrate 21 appears. When the etching of the substrate 21 starts, a change occurs in the plasma emission spectrum, and the change is etched. Since the etching operation is stopped by the control device 44 and detected by the end point detecting device 43, the amount of etching of the substrate 21 can be managed more accurately with the accuracy of the film thickness of the etching layer 21b. That is, in general, the control of the film thickness at the time of film deposition can be more accurately controlled than the control of the etching amount.

The present invention is not limited to the above embodiment, but can be implemented in various other modes.

For example, in the above description, only the case where the thickness of the second layer or the etching layer is equal to the height of the signal projection has been described, but the case where the height of the signal projection is less than the thickness of the second layer or the etching layer. But there are benefits. As described above, the height of the signal protrusion is λ / (4) where λ is the reproduction laser wavelength and n is the refractive index of the optical disk after being molded with the synthetic resin.
n), which is about 100 to 150 nm. Therefore, if the etching layer has a thickness of 1 micron, signal protrusions can be sufficiently formed. Since the whole has a thickness of 0.3 mm or more, it can be considered that the stamper is almost mechanically and thermodynamically a characteristic of the substrate. That is, a material having optimal characteristics according to the molding conditions can be selected as the substrate. On the other hand, the second
For the layer or the etching layer, an optimum material can be selected in consideration of the etching characteristics.

When the development is performed in a dry state, the steps of dry development, etching, and ashing can be performed continuously by replacing only the reaction gas in the apparatus shown in FIG. That is, in the etching apparatus shown in FIG.
6, the valve 38 is opened and closed, and a desired reaction gas is supplied into the chamber 30 from one of the pipes 39, 40, and 41, whereby only the reaction gas supplied into the chamber 30 is replaced. Dry development,
The steps of etching and ashing can be performed continuously. As a result, three processes can be processed by one apparatus,
The amount of capital investment can be significantly reduced. In addition, since handling of the master is eliminated between these steps, generation of defects such as adhesion of foreign matters can be prevented, and the yield can be greatly improved. Also, the production time can be shortened.

Further, the etching of the present invention is not limited to reactive ion etching, but may be sputter etching or ion beam etching.

According to the third to fifth embodiments of the present invention,
The following effects can be obtained. When the stamper substrate of the present invention is used, the number of steps can be reduced to half or less as compared with the conventional method. In particular, if a stamper substrate with a resist film that has been processed to a stamper size and a resist has already been applied is used, and dry development, etching, and resist removal are performed in the same chamber, the stamper required for molding can be produced with only three facilities. be able to.

Further, when the stamper substrate according to the present invention is used, the cost of production equipment can be reduced, and the area of the factory can be reduced. Further, since the polishing and cleaning of the glass disk, the resist coating device, the stamper back surface polishing device, and the electroforming device are not required, the processing capability of the pure water device and the waste liquid processing device may be small. Further, if a dry developed resist is used, a pure water device and a waste liquid treatment device are not required, and the capital investment can be greatly reduced.

Further, according to the substrate of the present invention, the wet processing is small or unnecessary. Therefore, at the time of drying the substrate after the wet processing, the occurrence of surface defects due to stains and adhesion of foreign matters is small, and a high-quality stamper can be produced with high yield.

In addition, the manufacturing cost of the stamper can be reduced for the above-mentioned reasons.

Further, the stamper can be manufactured in a short time for the above reasons.

Further, since the number of steps is reduced, the probability of occurrence of defects such as adhesion of foreign matter and scratches during the transfer and handling of the substrate is reduced, and the yield can be improved.

Further, titanium nitride, titanium oxide, tantalum, tungsten, chromium, molybdenum, cobalt, boron, nickel phosphorus, nickel boron,
On a substrate having an etching layer such as nickel-cobalt, if the thickness of the etching layer is the same as the height of the desired signal protrusion, the end point of the etching can be easily detected by the change in the emission spectrum of the plasma, and the etching accuracy can be increased. can do.

In the method and apparatus of the present invention, if a dry development resist is used, all processes are dry, and there is no process requiring know-how of processes such as chemical treatment. Can be.

Also, since there is no step using a chemical change, the process is stable.

Further, the cost for keeping the working environment such as temperature and humidity constant is not required.

As described above, the present invention is intended to reduce the cost of manufacturing a stamper and to produce a stamper having a good yield and high quality in a short time even if it has no experience.

It is to be noted that by appropriately combining any of the above-described various embodiments, the effects of the respective embodiments can be exhibited.

[0128]

According to the method of manufacturing a substrate for direct mastering according to the present invention, instead of forming a signal unevenness, for example, a signal projection on a glass substrate and then manufacturing a stamper, a substrate for a stamper is manufactured first. The signal unevenness, for example, the signal protrusion is formed thereon. Therefore, the substrate manufacturing factory for manufacturing the substrate and the stamper manufacturing factory for manufacturing the stamper can be separated, and the substrate manufacturing and the stamper manufacturing can be performed individually. Conventionally, if a defect occurs in the process of forming a stamper, it is necessary to start over from the beginning, but in the method of manufacturing a substrate for direct mastering of the present invention, only good substrates are passed to the stamper process, so that the overall yield is improved. Can be.

Further, according to the method of manufacturing a substrate for direct mastering of the present invention, the material of the substrate can be not only conventional nickel but also other metals, ceramics, glass, carbon, etc. which are difficult to be electroformed. The most suitable material can be selected economically and in terms of formability.

In the method for manufacturing a substrate for direct mastering and the method for manufacturing a stamper using the above-described substrate according to the present invention, if a substrate manufactured by the above-described substrate manufacturing method is used and a dry processing method is used in a post-process, After the resist is applied to the substrate, it is possible to perform a dry-only treatment that does not require pure water or chemicals. For this reason, there is no surface defect due to stains or foreign matter adhesion that is likely to occur during drying after wet processing, and a high-quality stamper can be produced with high yield.
Further, a pure water device and a waste liquid treatment device are not required, and the amount of capital investment can be greatly reduced.

In the method for manufacturing a substrate for direct mastering and the method for manufacturing a stamper using the above-described substrate according to the present invention, a substrate already coated with a resist is formed in a specific substrate manufacturing plant, and the substrate manufactured in the substrate manufacturing plant is manufactured. If used in an optical disk manufacturing plant separate from the substrate manufacturing plant, many optical disk manufacturing plants use only the laser recording device, heat treatment device, and dry development / etching / ashing equipment based on the substrate. The required stamper can be produced. Therefore, production equipment costs are reduced, and the factory area can be reduced.

Further, the stamper can be manufactured on the basis of the substrate in a short time for the above-mentioned reason.

Further, since the number of steps is reduced, the probability of occurrence of defects such as adhesion of foreign matter and scratches during the transfer and handling of the substrate is reduced, and the yield can be improved.

As the substrate, a nickel-based alloy is used, or titanium nitride, titanium oxide, tantalum, tungsten, chromium, molybdenum, cobalt, boron, niobium, nickel phosphorus, nickel boron, or nickel cobalt is formed thereon. If a stamper having a second layer is used, the stamper can be molded under the same molding conditions as those of a conventional nickel stamper in the method of manufacturing a stamper of the present invention.

[0135] Titanium nitride,
A second layer such as titanium oxide, tantalum, tungsten, chromium, molybdenum, cobalt, boron, niobium, nickel phosphorus, nickel boron, or nickel cobalt is provided, and the thickness of the second layer is set to a desired value for the signal protrusion. If the height is the same, the end point of the etching can be easily detected by a change in the emission spectrum of the plasma, and the etching accuracy can be increased.

Further, according to the method for manufacturing a substrate for direct mastering of the present invention, since there is no step that requires the know-how of a process such as a chemical treatment, even a manufacturer without experience can perform mastering.

Further, according to the method of manufacturing a substrate for direct mastering of the present invention, since there is no step using a chemical change, the process is stable.

Further, according to the method of manufacturing a substrate for direct mastering of the present invention, the cost for maintaining a constant working environment such as temperature and humidity is not required.

As described above, according to the method of manufacturing a substrate for direct mastering and the method of manufacturing a stamper using the above-described substrate of the present invention, a substrate that finally becomes a stamper is prepared without using a glass substrate. The stamper is completed by forming signal irregularities such as signal protrusions by direct etching on the stamper, so that the cost of manufacturing the stamper can be reduced without using a wet process, and there is no experience of a stamper having good yield and quality. This enables even workers to produce in a short time.

Further, in the present invention, a signal recording resist film is formed by applying a resist to a substrate which has been processed so as to fit a mold of a molding machine for molding an optical disk. Because of the configuration, for example, a resist such as a photoresist acting as a negative tone was applied in advance to form a resist film,
A stamper substrate with a resist film can be provided to a stamper manufacturer. After purchasing the stamper substrate with the resist film, the stamper manufacturer records the signal on the stamper substrate with the resist film using a device called a laser beam recorder, heat-processes, develops, etches, and removes the resist. , The stamper can be completed.

The thickness of the substrate for a stamper with a resist film is previously processed so as to fit a mold of a molding machine for molding an optical disk. Further, the inner and outer diameters of the stamper substrate with a resist film can also be processed in advance. For this reason, the manufacturer of the stamper does not need to have many facilities, and manufacturing costs such as material costs, consumables costs, and facility maintenance costs can be reduced. Further, since the number of steps is reduced to less than half of the conventional method, the yield can be improved.

In order to realize the above-mentioned new method, a resist acting on a negative tone can be used as a resist applied on a substrate for a stamper with a resist film. In this way, the exposed portions of the resist remain on the substrate as projections after recording and development. If dry etching is performed using the projections as a mask, irregularities, for example, signal projections can be formed on the substrate surface. Thereafter, the rest of the resist is removed by ashing to complete the stamper. If the resist is a dry developable resist, the development can be performed by a dry process. Then, the stamper can be manufactured without using pure water at all, and the merit can be obtained more.

Further, the above-described steps of development, etching and resist removal can be performed in the same chamber by changing only the reaction gas. As a result, it is possible to eliminate handling between processes and eliminate the opportunity for foreign matter to adhere.

[Brief description of the drawings]

FIGS. 1A, 1B, 1C, and 1D are schematic cross-sectional views illustrating steps of a method of manufacturing a substrate for direct mastering according to a first embodiment of the present invention.

FIG. 2 is a schematic view of an apparatus for simultaneous double-side polishing used in the method of manufacturing a substrate for direct mastering according to the first embodiment of the present invention.

FIG. 3 (a), (b), (c), (d), (e),
(F) is a schematic cross-sectional view showing a stamper manufacturing process using a substrate manufactured by the method for manufacturing a substrate for direct mastering according to the first embodiment of the present invention.

FIG. 4 is a cross-sectional view illustrating a substrate manufactured by a method for manufacturing a substrate for direct mastering according to a second embodiment of the present invention.

FIG. 5 (a), (b), (c), (d), (e),
(F) is a schematic cross-sectional view showing a stamper manufacturing process using a substrate manufactured by the method for manufacturing a substrate for direct mastering according to the second embodiment of the present invention.

FIG. 6 is a diagram of a substrate etching apparatus according to a second embodiment.

FIG. 7 is an explanatory view of a gear mechanism portion of the apparatus for simultaneous double-side polishing shown in FIG. 2;

8 (a), (b), (c), (d), (e),
(F) is a schematic cross-sectional view showing a stamper manufacturing process according to the stamper manufacturing method using the stamper substrate with the resist film according to the third embodiment of the present invention.

FIG. 9 (a), (b), (c), (d), (e),
(F) is a schematic cross-sectional view showing a stamper manufacturing process according to the stamper manufacturing method using the resist film-attached stamper substrate according to the fourth embodiment of the present invention.

FIG. 10 (a), (b), (c), (d),
(E), (f) is a schematic cross-sectional view showing a stamper manufacturing process according to a method for manufacturing a stamper using a stamper substrate with a resist film according to the fifth embodiment of the present invention.

11 (a), (b), (c), (d),
(E), (f), and (g) are schematic sectional views showing a conventional mastering step.

[Explanation of symbols]

1, 1 '... blank material, 2 ... polishing table, 3 ... polishing pad, 4 ... nozzle, 5 ... abrasive slurry, 6 ... polishing head, 7 ... substrate, 8 ... second layer of substrate, 9 ... negative type Photoresist film, 10 ... Signal recording laser beam, 11 ... Recording lens, 12 ... Signal protrusion, 12 '... Signal protrusion after etching, 13 ... Signal protrusion formed on substrate, 14 ... Negative photoresist film, 21 ... substrate, 21a ... base layer, 2
1b: etching layer, 22: negative type resist layer for dry development, 25: protrusion of resist remaining after dry development,
25 ': resist protrusion remaining after etching, 26 ...
Signal protrusions formed on the substrate, 30: etching chamber, 31: upper electrode, 32: lower electrode, 34: matching device,
35 high frequency power supply, 36 exhaust pump, 37 reactive gas supply pipe, 38 valve, 39 pipe from tank, 4
0: piping from the tank, 41: piping from the tank, 42
... Optical fiber for end point detection and monitoring, 43 ... End point detection device, 44 ... Control device, 50 ... Upper platen, 51 ... Lower platen, 5
2 ... Polishing pad, 53 ... Polishing pad, 54, 54 '... Carrier, 55 ... Internal gear, 56 ... Rotating shaft, 57 ... Sun gear, 107 ... Substrate, 107 ... Negative type dry developing resist layer, 112 ... Dry Resist protrusions remaining after development, 112 '... resist protrusions remaining after etching,
113: signal projections formed on the substrate; 117: substrate processed to a stamper size; 119: negative type resist layer for dry development; 122: projections of resist remaining after dry development; 122 ': resist remaining after etching Reference numeral 123 denotes a signal projection formed on the substrate, 200 denotes an optical device, 201 denotes a rotating device, 210 denotes a glass substrate, 22
0: positive photoresist, 240: pits formed by development, 250: conductive film, 260: nickel thick film.

Claims (18)

[Claims] 1. A method for manufacturing a substrate for direct mastering, wherein a signal projection is formed on a substrate by etching to form a stamper, wherein one surface of a blank material of the stamper is mirror-polished, and the other surface is polished more than a mirror surface. A method for manufacturing a substrate for direct mastering, characterized in that the substrate is processed to have an outer diameter. 2. After the blank material of the stamper is processed to the outer diameter of the stamper, any one of sputtering, ion plating, vacuum deposition, electroforming, and electroless plating is formed on the mirror-polished surface of the blank material. The method for manufacturing a substrate for direct mastering according to claim 1, wherein the metal layer is formed by one of the methods. 3. The substrate according to claim 1, wherein the substrate is made of a material containing at least one of nickel, chromium, aluminum, titanium, cobalt, iron, molybdenum, tungsten, boron, copper, and niobium. 3. The method for manufacturing a substrate for direct mastering according to 2. 4. The method for manufacturing a substrate for direct mastering according to claim 1, wherein the substrate is made of Si or a Si compound of SiO ₂ or SiC. 5. The method according to claim 1, wherein the substrate is made of glass. 6. The method according to claim 1, wherein the substrate is made of a material containing carbon as a main component. 7. The metal layer formed on the mirror-polished surface includes titanium nitride, titanium oxide, tantalum,
Tungsten, chromium, molybdenum, cobalt, boron, niobium, nickel phosphorus, nickel boron, or
3. The method according to claim 2, wherein the substrate is made of nickel cobalt. 8. The method for manufacturing a substrate for direct mastering according to claim 2, wherein the thickness of the metal layer formed on the mirror-polished surface is equal to the etching depth. 9. A direct mastering substrate manufactured by the method for manufacturing a direct mastering substrate according to claim 1. 10. A photoresist film is formed by applying a negative type photoresist on the substrate according to claim 9, and a signal is exposed and recorded on the photoresist film by laser beam irradiation. The substrate on which the signal is recorded by laser beam irradiation is subjected to a heat treatment to cause rearrangement of the polymer chains in the exposed portion of the photoresist film, and the unexposed portion of the resist film of the substrate is subjected to dry development. And removing only the exposed portions of the resist film as protrusions, performing dry etching using the protrusions as a mask, and removing the protrusions after etching by ashing to produce a stamper. 11. A substrate for an optical disk stamper used in direct mastering to form a signal projection on a substrate by etching to form a stamper, wherein the substrate is processed to fit a mold of a molding machine for molding an optical disk. A substrate for an optical disk stamper on which a resist is applied to form a resist film for signal recording. 12. The substrate for an optical disk stamper according to claim 9, wherein a resist is applied to the substrate and a signal recording resist film is formed on the substrate, which is processed so as to match a mold of a molding machine for molding an optical disk. 13. The optical disk stamper substrate according to claim 11, wherein the surface roughness of the back surface of the substrate is about 0.1 μm in center line average roughness. 14. The optical disk stamper substrate according to claim 11, wherein an inner or outer diameter or an outer diameter is processed so as to be attached to a mold of the molding machine for molding an optical disk. 15. The substrate according to claim 11, wherein the substrate has a two-layer structure including a base layer and an etching layer disposed on the base layer and having a thickness substantially equal to the height of the signal protrusion. 2. The substrate for an optical disk stamper according to claim 1. 16. The optical disc stamper substrate according to claim 11, wherein the resist is a negative resist. 17. The optical disk stamper substrate according to claim 11, wherein the resist is a resist that can be dry-developed. 18. A signal is recorded by exposing a signal to the resist film of the optical disk stamper substrate according to any one of claims 11 to 17 by irradiating the signal with a laser beam. The recorded substrate is subjected to a heat treatment to cause rearrangement of the polymer chains in the exposed portion of the resist film, and the unexposed portion of the resist film on the substrate is removed by dry development to expose the resist film. A method of manufacturing a stamper, wherein dry stamping is performed using the above-mentioned protrusions as a mask, and the above-mentioned protrusions after etching are removed by ashing to produce a stamper.