JP2001033981A - Resist developing solution for master disk of optical information recording medium and production of master disk of optical information recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a master disk of an optical information recording medium with high resolution of a resist. SOLUTION: A photoresist film 2 is formed on a substrate 1 and exposed in a prescribed pattern. Only the exposed part of the photoresist film 2 is removed by developing the photoresist film 2 with a resist developing solution 5 comprising an alkaline solution to produce the objective master disk of an information recording medium having fine ruggedness 6 corresponding to an information signal on the substrate 1. The resist developing solution 5 contains an additive containing at least one of amine and ammonium groups.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resist developing solution for preparing a master used for manufacturing an optical information recording medium such as an optical disk, and a method for manufacturing the master.

[0002]

2. Description of the Related Art Conventionally, a method for manufacturing a master disk of this type is based on a method in which a positive photoresist is applied to the surface of a glass master disk, exposed using a laser beam, and then exposed to an alkaline resist developer composed of an aqueous sodium hydroxide solution. Only the exposed portion of the resist was selectively removed to form an information pattern. Next, a conductive film made of nickel or the like is formed on the remaining resist surface, and electroforming is performed using the conductive film as an electrode to form a stamper. Using this stamper, optical disks are mass-produced by an injection molding method or the like.

[0003]

However, in the prior art, the resolution of the resist is not sufficiently increased, and when a fine information pattern (fine unevenness) is formed, the portion around the exposure spot is likely to be distorted. In addition, there is a problem that the resist surface is roughened, which eventually causes a noise in the optical information recording medium.

An object of the present invention is to provide a resist developing solution for an optical information recording medium master having a high resist resolution and a method for manufacturing an optical information recording medium master, by overcoming such disadvantages of the prior art.

[0005]

According to a first aspect of the present invention, a resist developing solution for an optical information recording medium master comprises, for example, poly-methacryltrimethylaminoethylammonium chloride, poly-methacryldimethylaminoethyl. And an alkaline solution containing an additive containing at least one of an amine group and an ammonium group of poly-allylamine, tetrapropylammonium hydroxide and tetrabutylammonium hydroxide.

According to a second aspect of the present invention, a positive type photoresist film is formed on a master disc.
After exposing the photoresist film to a predetermined pattern,
In the method for producing an optical information recording medium master for forming fine irregularities corresponding to information signals on the master by developing with a resist developer consisting of an alkaline solution and removing only the exposed portions, the resist developer is For example, an additive containing at least one of an amine group and an ammonium group such as poly-methacryltrimethylaminoethylammonium chloride, poly-methacryldimethylaminoethyl, poly-allylamine, tetrapropylammonium hydroxide, and tetrabutylammonium hydroxide. It is characterized by containing an agent.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS As the photoresist used in the present invention, for example, organic compounds such as naphthoquinonediazide and diazoketone can be used.

The additives having an amine group or an ammonium group used in the present invention include, for example, poly-methacryltrimethylaminoethylammonium chloride, poly-methacryldimethylaminoethyl, poly-allylamine, tetrapropylammonium hydroxide, tetrabutyl Ammonium hydroxide or the like is suitably used, and the content of the additive in the developer is 1% by weight or less, preferably 0.0005% by weight to 0.1% by weight.
Range. The molecular structural formulas of these additives are as follows.

(Poly-methacryltrimethylaminoethylammonium chloride)

[0010]

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(Poly-methacryldimethylaminoethyl)

[0012]

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(Poly-allylamine)

[0014]

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(Tetrapropylammonium hydroxide)

[0016]

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(Tetrabutylammonium hydroxide)

[0018]

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A buffer for maintaining the pH value of the developer;
In addition, various surfactants can be added to enhance the uniformity of development, and since the developer is alkaline, it is necessary to use a buffer or (and) a surfactant that is stable even in an alkaline solution.

As a buffer which is stable in an alkaline solution,
Examples include sodium metasilicate, sodium borate, and phosphoric acid.

Examples of the surfactant which is stable in an alkaline solution include anionic surfactants such as sodium lauryl sulfate, sodium myristyl sulfate, sodium stearyl sulfate, and sodium lauryl ether sulfate.

Next, a specific method for manufacturing a master for an optical information recording medium according to the present invention will be described with reference to FIG.

[Example 1] 200 mm in diameter and 10 m in thickness
m of the glass master 1 (see FIG. 1 (a)), surface-treated with hexamethyldisilazane to improve the adhesion to the resist, and then a positive photoresist (a naphthoquinonediazide-based organic compound). Shipley's product name MP-1400) spin-coated to a thickness of 100n
m, and then pre-baked to remove the residual solvent.

The thickness of the resist film 2 (see FIG. 1 (b)) is appropriately set to an extremely thin range of 80 to 300 nm so as to enable a high recording density. In the case of this embodiment, as described above. 1
00 nm.

As shown in FIG. 3 (c), the master was exposed spirally at a pitch of 0.74 μm using a laser beam 3 (exposure wavelength: 351 nm) by a cutting device for an optical disk.

Next, as shown in FIG. 1D, while the master 1 is being rotated, poly-methacryldimethylaminomethylammonium chloride (average molecular weight: 1000) is added to 0.00.
A developing solution 5 composed of MP-Developer (manufactured by Shipley Co., Ltd., alkali component, NaOH, molecular weight: 40) added to the resist film 2 is ejected from the nozzle 4 onto the resist film 2 by adding 0.05% by weight.
After developing for 0 second, an information pattern 6 having fine grooves was formed on the master 1 as shown in FIG. The surface condition of the information pattern 6 thus created was observed with an electron microscope, and the condition of the groove formed by development was determined.

Further, a diameter of 120 mm and a thickness of 0.6 m were prepared by injection molding using a master prepared in the same manner.
After an aluminum film was formed on a polycarbonate substrate having a thickness of m, the two substrates were bonded together to form an optical disk, which was mounted on an optical disk drive (laser light wavelength: 650 nm) to measure noise.

A master disk before exposure, which was exposed to a spot light having a diameter of 10 mm with varying illuminance, was also developed using the developing solution of this embodiment, and the γ value of the resist was determined from the resist film thickness after development. It was measured.

Example 2 As an alkaline developer, poly-methacryldimethylaminoethyl (average molecular weight 25
MP), to which 0.05% by weight of (00) was added.
er (manufactured by Shipley Co., Ltd., alkali component NaOH, molecular weight: 40), a development was performed in the same manner as in Example 1 to prepare a master, and various evaluations and measurements were performed.

Example 3 As an alkaline developer, poly-allylamine (average molecular weight 10,000) was used in an amount of 0.00
MP-Developer MF31 with 5% by weight added
2 (manufactured by Shipley Co., Ltd., product name: NaOH), developed in the same manner as in Example 1,
Various evaluations and measurements were performed.

[Comparative Example] As an alkaline developer, Na was used.
Using an OH aqueous solution, development was performed in the same manner as in Example 1 to prepare a master, and various evaluations and measurements were performed.

[0032]

The results of these evaluations are shown in the following table. The values of the disk noise in the table are based on the comparative example (0d
B).

Example 1 Example 2 Example 3 Comparative Example Pattern Shape Good Good Good Bad Resist Surface Smooth Smooth Smooth Uneven Large Disk Noise -2 dB -2 dB -3 dB 0 dB γ Value 10 8 12 3 As is clear from this table, Compared with the comparative example, the one according to the embodiment of the present invention has a high γ value which is a measure of the resolution of the resist, and accordingly, the pattern shape (groove shape) of the master is sharp and the flatness of the dist surface is high. From
Low disk noise and excellent performance.

In the above embodiment, poly-methacryldimethylaminomethylammonium chloride, poly-methacryldimethylaminoethyl, and poly-allylamine were used as additives, but tetramethylammonium hydroxide and tetramethylammonium silicate were added. Similar effects are obtained, and two or more kinds of additives can be used.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram illustrating a manufacturing process of an optical information recording medium master for explaining an example of the present invention.

[Brief description of reference numerals]

 Reference Signs List 1 master 2 resist film 3 laser beam 4 nozzle 5 information pattern

Claims (8)

[Claims] 1. A resist developing solution for an optical information recording medium master comprising an alkaline solution containing an additive containing at least one of an amine group and an ammonium group. 2. The method according to claim 1, wherein the additive is
Poly-methacryltrimethylaminoethylammonium chloride, poly-methacryldimethylaminoethyl,
A resist developer for an optical information recording medium master, comprising at least one organic compound selected from the group consisting of poly-allylamine, tetrapropylammonium hydroxide, and tetrabutylammonium hydroxide. 3. The method according to claim 1, wherein
A resist developing solution for an optical information recording medium master, wherein the resist developing solution contains a buffer for maintaining a PH value. 4. The resist developing solution for an optical information recording medium master according to claim 1, wherein the resist developing solution contains a surfactant. 5. A method of forming a photoresist film on a master, exposing the photoresist film to a predetermined pattern, and developing the photoresist film with a resist developer composed of an alkaline solution to remove only the exposed portions, In the method for manufacturing an optical information recording medium master for forming fine unevenness corresponding to an information signal on the above, the resist developer contains an additive containing at least one of an amine group and an ammonium group. A method for producing an optical information recording medium master. 6. The method according to claim 5, wherein the additive is
Poly-methacryltrimethylaminoethylammonium chloride, poly-methacryldimethylaminoethyl,
A method for producing a master optical information recording medium, comprising at least one organic compound selected from the group consisting of poly-allylamine, tetrapropylammonium hydroxide, and tetrabutylammonium hydroxide. 7. The method according to claim 5, wherein
A method for producing an optical information recording medium master, wherein the resist developer contains a buffer for maintaining a PH value. 8. The method for manufacturing a master optical information recording medium according to claim 5, wherein the resist developer contains a surfactant.