JP2001160242A - Method for manufacturing master disk for optical information recording medium and apparatus for the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To manufacture a master disk for a high-accuracy and high-density optical information recording medium which assures the uniformity of the thickness of a resist coating film on a substrate surface in order to increase the memory capacity of the optical information recording medium, such as optical disk. SOLUTION: The method for manufacturing the master disk of the optical information recording medium including a means for applying a primer 19 on a glass substrate 2, a means for drying this primer 19, a means for applying a photoresist 13 onto a primer layer 20 and a means for drying the applied photoresist 13 consists of stages for repeating the steps of applying the primer 19 on the glass substrate 2 within a closed vessel 1, then forcibly discharging the gas evaporated from the primer 19 from the vessel 1, applying the primer 19 in the enclosed vessel 1 and forcibly discharging the evaporated gas of the primer 19 in the same manner as described above, then applying the photoresist 13 in the reclosed vessel 1 and opening the inside of the vessel to the outdoor air, thereby drying the photoresist.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a method and an apparatus for manufacturing a master for forming an information recording layer on a substrate of an optical information recording medium.

[0002]

2. Description of the Related Art A technique for reproducing or recording high-density information using a laser beam is well known, and is mainly put to practical use as an optical disk. The optical disks can be broadly classified into a read-only type, a write-once type, and a rewritable type. The read-only type is called a disk called a compact disk on which music information is recorded or a laser disk on which image information is recorded. Disks and the like, and the write-once type are commercialized as document files and still image files, and the rewritable type are commercialized as data files for personal computers.

[0003] The optical disk has a thickness of 1.2 m.
In general, an information layer is provided on one main surface of a transparent resin substrate of m, and a protective film such as an overcoat is provided thereon, or the same protective plate as the substrate is bonded with an adhesive. . The information layer provided on the main surface of the substrate of the optical disk is transferred from a master on which a recording information layer is formed by pressing or the like when a transparent resin substrate is molded.

In order to increase the recording capacity of such an optical disc, it is essential to make the recording information pattern finer. Next, a method of manufacturing a conventional optical disk master is shown in FIG. First, an extremely smooth glass substrate 2 was prepared as shown in FIG.
It is fixed on the turntable 5 as shown in FIG. The turntable 5 is mounted on the upper part of the rotary shaft 6 and can be driven by a motor (not shown).

In this state, the surface of the glass substrate 2 is cleaned by a method such as ultrasonic cleaning and then dried. Next, FIG.
As shown in (B), the primer 10 is applied to the surface of the glass substrate 2 from the primer application nozzle 3 and dried to form the primer layer 12 (FIG. 6C).

[0006] Thereafter, as shown in FIG.
Is applied on the glass substrate 2 on which the primer layer 12 is formed, and the table 5 is rotated to be uniformly dispersed on the glass substrate 2 to form a photoresist layer 13 (FIG. 6D). Thereafter, in order to volatilize the organic solvent component of the photoresist layer 13, heating is performed using a hot plate or an oven (not shown).

The primer 10 shown in FIG.
Is to enhance the adhesion between the photoresist 11 of FIG. 6 (C) and the surface of the glass substrate 2, and conventionally, hexamethyldisilazane (hereinafter, HMDS), a silane coupling agent, a titanium coupling agent and the like are generally used. Used. Next, as shown in FIG. 6D, a laser beam L is irradiated to expose the photoresist layer 13 to a pattern corresponding to a predetermined information signal.

Subsequently, as shown in FIG. 6E, the exposed portion of the photoresist layer 13 is treated with a developing solution 14 to develop and remove the exposed portion. As a result, an uneven pattern 15 corresponding to the information signal as shown in FIG. Next, an uneven pattern 15 as shown in FIG.
Then, a nickel metal film 16 is formed by a method such as a sputtering method, a vapor deposition method, and an electroless plating method.

Then, as shown in FIG. 6H, a nickel layer 17 is deposited and formed to a desired thickness by electroplating using the metal film 16 as an electrode, and the metal film 16 and the nickel layer 17 are formed on the glass substrate 2. 6 and the photoresist remaining on the surface is washed and dried, and FIG.
A master (hereinafter, stamper) 18 as shown in (I) is completed.

In such a method of manufacturing a master, it is essential to make the thickness of the photoresist layer 13 thin and uniform in order to cope with the above-described miniaturization of the recording information pattern in order to increase the storage capacity. Further, for this purpose, it is necessary to sufficiently increase the adhesion between the glass substrate 2 and the photoresist layer 13, and the performance of the primer becomes a problem.

[0011]

In the process of manufacturing the conventional photoresist layer 13, HMDS, a silane coupling agent, a titanium coupling agent and the like are used as primers. In order to form a uniform photoresist layer, each primer has its own problems as follows.

First, the silane coupling agent needs to be applied to the glass substrate 2, washed with ultrapure water and isopropyl alcohol, baked at 100 ° C. or higher for several hours, and then cooled. There are problems that it takes time and that dedicated equipment such as a washing machine and an oven must be provided. Next, the titanium coupling agent is applied to the glass substrate 2 with a spin coater or the like, and is then shaken off and dried. Therefore, the application process is simple. Reacts with moisture in the air to form white crystals.

Accordingly, the titanium coupling agent adheres to the tip of the nozzle for applying the primer and solidifies, and the solidified titanium coupling agent adheres to the surface by dropping onto the glass substrate 2 or the like, and is subsequently applied to the photo-coating layer. It tends to occur that a good stamper 18 that appears as unevenness or spots on the resist and can form a miniaturized pattern cannot be obtained.

On the other hand, HMDS has a disadvantage that it is inferior in adhesion to other primers, but has the advantage that the coating process is simple. In addition, the conventional coating method has a problem that it is difficult to form a thin and uniform photoresist layer. That is, FIG. 5 is an explanatory view of a conventional coating means, and as shown in FIG.
a in a closed container 1 by closing the glass substrate 2
While the glass substrate 2 is rotated at a low speed, the primer vapor 19 vaporized by a bubbling device (not shown) is sprayed from the application nozzle 3 and then the photoresist 11 is applied as shown in FIG. The method of doing is performed.

However, in this method, the primer vapor 1
When pulsation occurs in the ejection of the nozzle 9, it becomes difficult to uniformly form the primer layer 12 on the surface of the glass substrate 2, and as a result, the wettability of the primer vapor 19 on the surface of the glass substrate varies, so that There is a problem that it is difficult to uniformly distribute the photoresist layer 13 on the surface of the glass plate 2 and to ensure a uniform thickness of the photoresist layer 13.

After the application of the primer, the photoresist 11 is continuously applied in the same container 1 as shown in FIG.
As shown in FIG. 5B, since the primer vapor 21 is filled in the container, as shown in FIG. 5C, the residual primer vapor 21 in the container becomes the organic solvent component 23 contained in the applied photoresist 11. There is a problem that the evaporation is hindered and it is difficult to ensure a uniform film thickness of the photoresist 13.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a method of manufacturing a master of an optical information recording medium with high accuracy and high density, while ensuring uniformity of a resist coating thickness on a substrate surface.

[0018]

According to the present invention, there is provided a method for producing a master of an optical information recording medium, comprising: means for applying a primer on a glass substrate; means for drying the primer; and applying a photoresist on the primer layer. Means, and a method of manufacturing a master disc of an optical information recording medium including means for drying the applied photoresist, after applying a primer on the glass substrate in a closed container, the evaporating gas from the primer the said gas Forcibly evacuate the container, then apply the primer in the closed container again, repeat the forced evacuation of the evaporating gas of the primer in the same manner as above, and then apply the photoresist in the closed container again Thereafter, the inside of the container is opened with the outside air and dried.

That is, the coating process of the primer vapor, which has been conventionally performed in one coating process, is divided into several steps, thereby making the wettability of the surface of the glass substrate uniform and preventing the volatilization of the organic solvent component of the photoresist. After exhausting and removing the residual primer vapor in the container, the photoresist coating process is performed, so that the uniformity of the resist coating film thickness on the substrate surface can be ensured, and a high-precision and high-density optical information recording medium master can be obtained. It is done.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention is a method for manufacturing a master for forming an information recording layer on a glass substrate, comprising: means for applying a primer on the glass substrate; Means for drying the primer, means for applying a photoresist on the primer layer, and means for drying the coated photoresist, the method for producing a master of an optical information recording medium, wherein the glass in a closed container After applying the primer on the substrate, the evaporative gas from the primer is forcibly exhausted from the container, and then, after applying the primer in the closed container again, the evaporative gas for the primer is forcibly exhausted as described above. This is repeated, and thereafter, the photoresist is applied in the closed container, and the inside of the container is opened to the outside air and dried.

That is, the present invention relates to a method of applying a primer layer before applying a photoresist in a number of steps to make the primer layer uniform and to prevent residual organic solvent vapor from evaporating in an organic solvent in the photoresist. Is exhausted and removed to ensure uniformity of the photoresist film thickness distribution. According to a second aspect of the present invention, in the above-mentioned method for producing a master for an optical information recording medium, after applying a primary primer on a glass substrate, the coated surface is coated at a temperature of 20 ° C to 25 ° C.
℃ in dry air blown at a flow rate of 3m ³ / min ~5m ³ / min was maintained above is used for drying the primary primer.

According to the present invention, the evaporation gas from the primer layer on the surface of the glass substrate before the application of the photoresist is dried at an early stage by spraying dry air under a certain condition to make the state of the primer layer uniform and to make the photoconductive layer uniform. By more reliably evacuating and removing the residual primer vapor in the container that hinders the volatilization of the organic solvent component of the resist, it has the effect of ensuring further uniformity of the photoresist film thickness distribution.

The reason why the temperature condition of the dry air is set to 20 ° C. to 25 ° C. is to perform a normal temperature treatment, and particularly to omit the cost of cooling and heating. To the flow rate and 3m ³ / min ~5m ³ / min, when less than 3m ³ / min,
This is because the amount of air for drying is insufficient and it takes too much processing time to reach a predetermined drying state. If the air amount is more than 5 m ³ / min, the primer layer may be affected by the wind speed, and This requires large-scale equipment, which is uneconomical.

A third aspect of the present invention relates to an apparatus for manufacturing a master of an optical information recording medium for performing the above method, wherein an air supply port is provided on an upper surface.
An exhaust port is formed on the floor surface, and a rotating table that supports the glass substrate is rotatably supported in a container that can be closed, and a coating nozzle can be moved in the radial direction of the rotating table on the upper surface of the rotating table. It is supported by. With this device, the above invention can be easily implemented.

According to a fourth aspect of the present invention, in the apparatus for manufacturing a master of an optical information recording medium according to the third aspect, a conditioned air supply means is communicated with an air supply port formed on an upper surface of a container that can be closed. Is what it is. By this conditioned air supply means,
Air at any temperature and drying conditions can be supplied, and drying conditions most suitable for primers and photoresists can be set.

An embodiment of the present invention will be described below with reference to FIGS. (Embodiment) FIG. 1 shows an apparatus for performing a primer treatment and a photoresist coating treatment on a glass substrate in an apparatus for manufacturing an original master for forming an information recording layer on a glass substrate. In the case of this apparatus, the priming and the photoresist application are performed successively in the same container.

In FIG. 1, a container 1 is applied with a primer on a glass substrate 2 installed therein, and is dried by evaporation.
Subsequently, a photoresist is applied and shake-dried. Inside, a holder table 5 is supported by a rotating shaft 6, and a motor 7 is provided on the rotating shaft 6 so that rotation can be controlled at a low speed to a high speed. . The above holder table 5
On the upper surface, a primer coating nozzle 3 and a photoresist coating nozzle 4 are supported so as to be able to move in parallel in the radial direction of the holder table 5, and the container 1 is provided with lids 8a and 9a that can be opened and closed. An air outlet 8 and an exhaust port 9 are provided.

Although not shown, the container 1 is also provided with an ultrasonic cleaning device (not shown) for cleaning the surface of the glass substrate 2 attached to the holder table 5. The above-mentioned primer coating nozzle 3 and photoresist coating nozzle 4 are supported so as to be able to move in parallel in the radial direction from the rotation center 2a of the glass substrate 2 which rotates together, and as shown in FIG. ) Is linearly moved in the radial direction of the glass substrate 2 and, as shown in FIG.
May be moved in an approximate linear manner in the radial direction through the center.

Although not shown, a bubbling device for bubbling the primer using a nitrogen gas or the like is connected to the primer supply source of the primer coating nozzle 3. Open / close lid 8 for air outlet 8 and exhaust port 9
Reference numerals a and 9a denote hermetic lids, respectively, so that the inside of the container 1 can be sealed when the lid is closed.

The atmosphere in the container 1 can be controlled by forcibly supplying and exhausting air from the air outlet 8 and the exhaust port 9. next,
A method for manufacturing a master of an optical information recording medium using the above apparatus will be described. First, an extremely smooth glass substrate 2
Is fixed on the table 5 by a suction device (not shown) provided on the rotating table 5 as shown in FIG. 1, and the surface of the glass substrate 2 is washed with an ultrasonic cleaning device (not shown) and then dried.

At this time, if water droplets remain on the glass substrate 2, a uniform photoresist layer cannot be formed in the subsequent photoresist coating step, so that the surface of the glass substrate 2 is sufficiently dried. Specifically, in the case of performing the spin-off drying, it is desirable to rotate the glass substrate 2 at a rotation speed of 1000 rpm or more for 2 minutes or more. Next, the process proceeds to a primer coating process. 4 (A) to 4 (F) show the steps of applying a primer and a photoresist.

First, as shown in FIG. 4A, the air outlet 8 and the exhaust port 9 are closed to seal the container 1, and
The rotary table 5 is rotated at a low speed of 100 rpm, and the glass substrate 2 on the rotary table 5 is sprayed with a primer vapor 19 made of HMDS bubbled with N ₂ gas from the surface of the glass substrate 5 at a height of 3 mm to 10 mm for coating. .

At this time, the coating nozzle 3 connected to a bubbling device (not shown) performs coating while moving from the outermost periphery of the glass substrate 2 to the center as shown by an arrow, and the primer vapor 19 spreads over the entire glass substrate 2. So that it is distributed. Then, the primer is applied to the glass substrate surface, and the primer reacts with water molecules on the substrate surface, and the primary primer layer 20 (FIG. 4)
(B)) is formed.

Incidentally, when the primer is applied by the above-mentioned method while the container 1 is not sealed and the air is exhausted from the exhaust port 9, the primer adheres to the surface of the glass substrate and is discharged before reacting. There is a problem that a sufficient primer layer cannot be formed on the surface, adhesion to a photoresist layer to be applied later cannot be obtained, and the resist layer is peeled off from the glass substrate in the developing step.

After the primer 19 is applied to the entire surface of the glass substrate 5, the air outlet 8 and the air outlet 9 are opened as shown in FIG. % Of dry air was blown at a flow rate of 4 m ³ / min, and at the same time, the air in the container 1 was forcibly exhausted from an exhaust port 9 connected to a centrifugal blower (not shown) to apply the air onto the substrate 2. The primer 19 made of HMDS is dried while diffusing and penetrating into the surface of the glass substrate 2.

After sufficient drying, as shown in FIG. 5C, the air outlet 8 and the exhaust port 9 were closed to close the container 1, and the surface of the glass substrate 2 was vaporized again by the bubbling device. Primer vapor 19 is applied to primer application nozzle 3
It is applied from a height of 3 mm to 10 mm from the surface of the glass substrate. At this time, similarly to the above, the glass substrate 2 is
It is rotated at a low speed of pm to 100 rpm, and the primer application nozzle 3 is moved from the outermost periphery of the glass substrate 2 to the center so that the primer vapor 19 spreads over the surface of the glass substrate 2. The primer on the surface of the glass substrate 2 reacts with water molecules on the surface of the substrate to form a primer layer 20.

Next, as shown in FIG. 4 (D), the air outlet 8 and the air outlet 9 are opened, and clean conditioned air adjusted to a temperature of 22 ° C. and a humidity of 55% is blown from the air outlet 8 onto the surface of the glass substrate. Simultaneously, by opening the exhaust port 19, the primer vapor 21 remaining in the container 1 is forcibly exhausted from the exhaust port 19. In order to sufficiently exhaust the residual primer vapor 21, when the flow rate of the clean conditioned air is 4 m ³ / min, the exhaust time is desirably 5 minutes or more.

By repeating the above-described primer application and forced evacuation several times in FIGS. 4A to 4D, the wettability of the glass substrate surface by the primer layer formed before the photoresist application is obtained. Is uniform. Subsequently, as shown in FIG. 4E, the open / close lids 8a and 9a are closed,
The container 1 is sealed again, and a certain amount of the photoresist 11 is supplied from the photoresist coating nozzle 4 onto the glass substrate.
As shown in FIG. 4 (F), the photoresist is uniformly dispersed on the surface of the glass substrate by rotating the glass substrate 2 at a high speed while evacuating the residual primer under the same conditions as when exhausting the residual primer. Is volatilized to form a photoresist layer 13 on the glass substrate 2.

By repeating the above-described primer application and forced evacuation several times in FIGS. 4A to 4D, the wettability of the glass substrate surface by the primer layer formed before the photoresist application is obtained. Is uniform, and
Due to the effect of removing the residual primer that hinders the volatilization of the organic solvent component of the photoresist from the container 1, the thickness of the photoresist layer 13 to be applied and formed later can be kept uniform.

The thickness and distribution of the photoresist layer are determined by the viscosity of the photoresist, the amount of drop, the rotation speed of the glass substrate, the atmosphere in the container 1, and the like. In addition, as the primer 19, a micropositive primer (Shipley), and as the photoresist 11, S1805 (Shipley), IP3000 series (Tokyo Oka) and the like can be used.

Subsequent steps for manufacturing the stamper are basically the same as those in the related art. That is, after the photoresist 13 is applied, the photoresist 13 is heated on a hot plate or an oven in order to sufficiently volatilize the organic solvent contained in the photoresist, stabilize the film thickness and adjust the sensitivity of the photoresist. That is, by irradiating the glass substrate 2 on which the photoresist layer 13 is formed with laser light L as shown in FIG. 6 (D), the photoresist layer 13 is exposed in a pattern corresponding to a predetermined information signal. I do.

Subsequently, as shown in FIG. 6 (E), the exposed portion is developed and removed by treating the photoresist layer 13 with a developing solution 14, and the unevenness corresponding to the information signal as shown in FIG. 6 (F) is obtained. The pattern 15 is formed. Next, FIG.
As shown in FIG. 6, a nickel metal film 16 is formed on the uneven pattern 15 by a sputtering method. Then, FIG.
As shown in FIG. 5, a nickel layer 17 is formed by electroplating using the metal film 16 as an electrode to a desired thickness, and then the metal film 16 and the nickel layer 17 are peeled off from the glass substrate 2 and remain on the surface. The remaining photoresist is washed and dried to complete the stamper master 18 as shown in FIG. 6 (I).

[0043]

As described above, according to the present invention, the primer coating and the evacuation of the chemical treatment chamber are repeatedly performed several times to thereby wet the glass substrate surface by the primer layer formed before the photoresist coating. The uniformity of the properties and the effect of removing the residual primer in the container that hinders the volatilization of the organic solvent component of the photoresist,
The film layer of the photoresist layer to be applied and formed later can be kept uniform.

In such a method of manufacturing a master, a master of a high-precision optical information recording medium can be manufactured by making the coating thickness of the resist thinner and uniform, and the recording information accompanying the increase in the recording capacity is increased. It is possible to cope with miniaturization of patterns.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a schematic configuration of an optical information recording medium master manufacturing apparatus according to an embodiment of the present invention.

FIG. 2 is a longitudinal sectional view showing a schematic configuration of a nozzle portion of an optical information recording medium master manufacturing apparatus according to an embodiment of the present invention.

FIG. 3 is a main part plan view showing another schematic configuration of the nozzle portion of the optical information recording medium master manufacturing apparatus according to the embodiment of the present invention;

FIGS. 4A to 4D are process explanatory views of a method for manufacturing a master of an optical information recording medium according to an embodiment of the present invention, wherein FIGS. Process explanatory view showing resist application state

FIG. 5 is an explanatory view showing a schematic configuration in the case of manufacturing a photoresist layer of a conventional optical information recording medium (A) to (A).
(B) is a process explanatory view showing a primer applied state, and (C) to (D) are photoresist applied states.

FIG. 6 is a diagram showing a schematic configuration of a conventional method for manufacturing a master of an optical information recording medium.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 container 2 glass substrate 3 primer coating nozzle 4 resist coating nozzle 5 holder table 6 rotating shaft 7 motor 8 air outlet 9 exhaust port 10 primer 11 photoresist 12 primer layer 13 photoresist layer 14 developer 15 pattern 16 metal film 17 nickel Layer 18 Stamper 19 Primer vapor 20 Primer layer 21 Residual primer 23 Volatile organic solvent

Continuing on the front page (72) Inventor Hideyuki Ishimaru 1006 Kazuma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. Reference) 2H025 AA14 AB20 AC08 AD03 DA19 DA35 EA05 FA10 5D121 BA03 BA05 BB02 BB04 BB38 EE16 EE19 EE22 EE23 EE24 GG18 GG20

Claims (4)

[Claims] 1. An optical system comprising: means for applying a primer on a glass substrate; means for drying the primer; means for applying a photoresist on a primer layer; and means for drying the applied photoresist. In the method for manufacturing a master for an information recording medium, after applying a primer on the glass substrate in a closed container, the evaporating gas from the primer is forcibly exhausted from the container, and then the primer is re-closed in the closed container. After the application, the repeated evacuation of the evaporating gas of the primer is repeated in the same manner as described above, and then the photoresist is applied in a closed container again, and the inside of the container is opened to the outside air and dried, and the master of the optical information recording medium is dried. Production method. 2. The method for manufacturing a master of an optical information recording medium according to claim 1, wherein a primer is applied on a glass substrate, and then the coated surface is dried at a temperature of 20 ° C. to 25 ° C. and a humidity of 50% to 58%. master method of manufacturing an optical information recording medium of drying the primer blowing air at a flow rate 3m ³ / min ~5m ³ / min. 3. An air supply port is formed on an upper surface, and an exhaust port is formed on a floor surface. A rotary table for supporting a glass substrate is rotatably supported in a container whose lid can be closed. An apparatus for manufacturing a master of an optical information recording medium, wherein a nozzle is supported movably in a radial direction of the rotary table. 4. The optical information recording medium according to claim 3, wherein a conditioned air supply means communicates with an air supply port formed on an upper surface of the lid-closable container. Master production equipment.