JP3125917B2 - Method of manufacturing base material for manufacturing electronic components - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coating material for forming an unnecessary resist adhered to at least a portion of a peripheral portion, an edge portion and a back surface of a substrate used for manufacturing a liquid crystal display or a plasma display, particularly a glass square substrate. The present invention relates to a method for manufacturing a base material for manufacturing electronic components by removing a coating layer or a resist film formed by drying the coating layer.

[0002]

2. Description of the Related Art Conventionally, as an unnecessary resist forming coating agent or a resist film removing liquid adhered to a peripheral portion, an edge portion, or a back surface of a silicon wafer substrate used for manufacturing a semiconductor device, for example, a resist solvent is used. Propylene glycol monomethyl ether acetate or a mixture thereof and propylene glycol monomethyl ether, which has low toxicity and is excellent in safety, has been widely used.

However, when such a material is applied to, for example, a glass square substrate used for manufacturing a liquid crystal element, a necessary resist to be left and a resist near an interface from which the unnecessary resist is removed are bulged, and a vertical cross section is formed. In addition, there is a problem that the properties are insufficient and the resist remains after the unnecessary resist is removed.

[0004] If such swelling or resist residue occurs, it has an adverse effect in the subsequent process, and a high quality liquid crystal element cannot be obtained. Therefore, there is no swelling of the resist near the interface, and the resist has excellent verticality, and There has been a demand for the development of a resist removing solution having good cleaning and removing properties that does not leave a resist residue. Further, if the removal liquid remains in the cleaning portion, it will have an adverse effect on the subsequent steps. Therefore, a removal liquid having excellent drying properties is desired.

[0005]

SUMMARY OF THE INVENTION Under such circumstances, the present invention has a high safety to the human body and a substrate used for manufacturing a liquid crystal display or a plasma display, particularly a peripheral portion of a glass square substrate. Unnecessary resist-forming coating material or resist film adhering to at least a part of the edge portion and the back surface can be efficiently removed in a short time, and a vertical resist cross section with no resist bulge near the interface is formed. To provide a method for easily and efficiently producing a base material for producing electronic components using a resist removing solution having excellent cleaning properties, which preferably does not cause a resist residue, and which preferably has excellent drying properties. It was made for the purpose.

[0006]

Means for Solving the Problems The present inventors have conducted intensive studies on a resist removing solution, particularly a solution for removing a resist applied to a square substrate used for a liquid crystal display or a plasma display. The use of a remover mainly composed of mono-lower alkyl ether enables efficient removal of an unnecessary coating layer of a resist-forming coating agent adhered to the substrate and a resist film generated by drying the coating layer in a short time, and also in the vicinity of the interface. And found that a vertical resist cross section was obtained without the swelling of the resist, and based on this finding, the present invention was completed.

That is, according to the present invention, when a resist-forming coating material is applied to a substrate to form a resist film,
Before or after the coating layer is dried, an unnecessary coating layer adhered to at least a part of the peripheral portion, the edge portion, and the back surface of the substrate or a resist film formed by drying the same is formed from dipropylene glycol mono-lower alkyl ether only. Or a drying treatment after removing with a resist removing solution, or at least 65% by weight of dipropylene glycol mono-lower alkyl ether, with the remainder having a boiling point of 75 to 130 ° C and a vapor pressure at 20 ° C of 5 to 75 mm.
An object of the present invention is to provide a method for producing a substrate for producing electronic components, wherein the substrate is removed with a resist removing liquid selected from a mixed solvent consisting of only Hg volatile organic solvents.

[0008]

DETAILED DESCRIPTION OF THE INVENTION In the method of the present invention, dipropylene glycol mono-lower alkyl ether alone or a volatile organic solvent having a boiling point of 75 to 130 ° C. and a vapor pressure of 5 to 75 mmHg at 20 ° C. is used as a resist removing solution. It is necessary to remove the unnecessary coating layer of the resist-forming coating material or the resist film formed by drying it using a mixed solvent, and the other conditions are the conventional base materials for electronic component manufacturing by lithography. Is exactly the same as when

The dipropylene glycol monoalkyl ether used as the resist removing solution includes
Preferred are those whose alkyl group is a lower alkyl group, such as dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monopropyl ether, and dipropylene glycol monobutyl ether. Dipropylene glycol monomethyl ether is preferred because it has excellent resist removal properties, safety and drying properties. These dipropylene glycol monoalkyl ethers may be used alone or in combination of two or more.

As described above, the dipropylene glycol monoalkyl ether alone may be used as the resist removing liquid. However, in order to further improve the drying property of the surface after the removal, the dipropylene glycol monoalkyl ether is used. Mixtures of other volatile organic solvents can be used. Another easily volatile organic solvent is acetic acid.
n-Propyl [boiling point 102 ° C, vapor pressure 25mmHg
(20 ° C.)], isopropyl acetate [boiling point 89 ° C., vapor pressure 43 mmHg (20 ° C.)], n-butyl acetate [boiling point 126 ° C., vapor pressure 10 mmHg (20 ° C.)], isobutyl acetate [boiling point 118 ° C., vapor pressure 13mmHg
(20 ° C.)], a lower alkyl acetic acid solvent such as methyl ethyl ketone [boiling point 80 ° C., vapor pressure 71
mmHg (20 ° C)], methyl propyl ketone [boiling point
102 ° C., vapor pressure 12 mmHg (20 ° C.)], methyl isobutyl ketone [boiling point 116 ° C., vapor pressure 17 mm
Hg (22 ° C.)] and propylene glycol monomethyl ether [boiling point 120 ° C.
Vapor pressure 8 mmHg (20 ° C)], ethylene glycol monomethyl ether [boiling point 125 ° C, vapor pressure 6 mm
Hg (20 ° C.)] and a boiling point of 75 to 13 such as a lower alkylene glycol mono-lower alkyl ether solvent.
Organic solvents having a vapor pressure of 5 to 75 mmHg at 0 ° C and 20 ° C are exemplified. These volatile organic solvents may be used alone or as a mixture of two or more. In this case, the mixing amount of these other volatile organic solvents must be selected within a range not exceeding 35% by weight based on the total amount of dipropylene glycol monoalkyl ether. If this amount exceeds 35% by weight, a residue of the resist remains on the surface after the removal, causing a trouble. From the viewpoints of drying properties and suppression of resist residues, the more preferable mixing amount of these other volatile organic solvents is based on the total amount with dipropylene glycol monoalkyl ether.
The range is from 5 to 35% by weight, and particularly preferably from 10 to 30% by weight. By using such a volatile organic solvent in combination, the drying property of the removal liquid can be improved.

The coating composition for forming a resist used in the method of the present invention is generally used for the production of various electronic component elements, and generally comprises a photosensitive substance and a film-forming substance, It can be developed with an aqueous solution. Particularly advantageous resists having various required characteristics that can be sufficiently adapted to recent microfabrication include positive photoresists, particularly those comprising a composition containing a quinonediazide-based photosensitive substance and a film-forming substance.

As the photosensitive substance, quinonediazide group-containing compounds, for example, sulfonic acids of quinonediazides such as orthobenzoquinonediazide, orthonaphthoquinonediazide and orthoanthraquinonediazide, and compounds having a phenolic hydroxyl group or amino group are partially or completely esterified. Compounds having a phenolic hydroxyl group or an amino group include, for example, 2,3,4-trihydroxybenzophenone, 2,2 ', 4,4'-tetra Polyhydroxybenzophenone such as hydroxybenzophenone, 2,3,4,4'-tetrahydroxybenzophenone, or alkyl gallate, aryl gallate, phenol, p-methoxyphenol, dimethylphenol, hydroquino , Bisphenol A, naphthol, pyrocatechol, pyrogallol, pyrogallol monomethyl ether, pyrogallol-1,3-dimethylether, gallic acid, gallic acid, aniline, p-aminodiphenylamine, etc. No. Particularly preferred quinonediazide group-containing compounds are the above-mentioned polyhydroxybenzophenone and naphthoquinone-1,2-diazide-5-
Completely or partially esterified with sulfonyl chloride or naphthoquinone-1,2-diazide-4-sulfonyl chloride, especially having an average degree of esterification of 70%
The above are preferred.

Examples of the film-forming substance include novolak resins obtained from phenols, cresols, xylenols and the like and aldehydes, acrylic resins, copolymers of styrene and acrylic acid, polymers of hydroxystyrene, polyvinylhydroxybenzoates. And alkali-soluble resins such as polyvinylhydroxybenzal are effective.

A particularly preferred positive type photoresist uses a cresol novolak resin as a film-forming substance. The cresol novolak resin has a weight-average molecular weight of 2000 to 200 obtained by cutting a low molecular weight region.
00, preferably in the range of 5000 to 15000.

In the above-mentioned positive type photoresist, the above-mentioned photosensitive substance is blended in an amount of usually 10 to 40 parts by weight, preferably 15 to 30 parts by weight with respect to 100 parts by weight of the film-forming substance. If the amount exceeds 40 parts by weight, the sensitivity is remarkably poor.

If necessary, other compatible dyes, such as coumarin dyes and azo dyes, may be added to the resist. Further, other additives such as additional resins, Plasticizers, stabilizers, or commonly used substances such as colorants and contrast improvers for making the pattern obtained by development more visible can also be added.

Next, the method of the present invention will be described in more detail. This method has two modes. First, in the first method, a coating material for forming a resist is applied to a substrate such as a glass square substrate by a known means such as a bar coater method or a roll coater method, and then the substrate is coated. After removing the unnecessary coating layer of the resist-forming coating agent adhered to at least a part of the peripheral portion, the edge portion, and the back surface with the resist removing liquid in advance, the substrate for electronic component manufacturing is dried by performing a drying treatment. To manufacture. At this time, there is no particular limitation on the method of removing the unnecessary coating layer of the resist forming coating agent,
Although various methods can be used, for example, after inserting the edge of the substrate into the reservoir filled with the removal liquid in advance from the horizontal direction, the edge of the substrate is immersed in the removal liquid in the reservoir for a predetermined time. A method is preferred.

Next, in the second method, a coating material for forming a resist is applied to a substrate such as a glass square substrate in the same manner as in the first method, and then dried to form a resist film. . Next, an unnecessary resist film adhered to at least a part of the peripheral portion, the edge portion, and the back surface of the substrate is removed with a resist removing liquid in the same manner as in the first method to produce a base material for electronic component production. I do.

[0019]

According to the method of the present invention, not only is the safety to the human body high, but also a resist layer formed by drying an unnecessary coating layer of a resist forming coating agent adhered to the peripheral portion, the edge portion or the back surface of the substrate. It can effectively remove the film in a short time, and can form a vertical resist cross section with no swelling of the resist near the interface. Is also excellent. The base material for electronic component production obtained by the method of the present invention having such characteristics can provide a device having good quality.

[0020]

Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

Examples 1 to 4 and Comparative Examples 1 and 2 A square glass substrate having a chromium layer (550 mm × 650 m
m) On top of which is a positive resist OFPR PR-11
[Applied by Tokyo Ohka Kogyo Co., Ltd., containing a quinonediazide group-containing compound and a cresol novolak resin] by a coating method so as to have a dry film thickness of 1.1 μm, followed by drying under reduced pressure and drying to a certain extent. A substrate on which a resist film was formed was prepared.

Next, an unnecessary resist removing device EBR mounted on TR-36000 (manufactured by Tokyo Ohka Kogyo Co., Ltd.)
The base material is treated for 8 seconds with each of the resist removing liquids shown in Table 1 supplied to the reservoir of [Tokyo Ohka Kogyo Co., Ltd.], then exhausted and dried to remove unnecessary portions of the resist film. The state was visually observed, and the cleaning and removability was evaluated as ○ when completely removed, Δ when a small amount of resist remains, and X when a large amount of resist remains.

Next, with respect to the sample whose unnecessary portions have been completely removed by the above operation, the cross section from which the resist film has been removed is measured by a stylus type step difference measuring device [DEKTAK, manufactured by Nippon Vacuum Engineering Co., Ltd.]. The measurement was carried out, and the cross-sectional shape of the resist after removal was evaluated as ○ when there was no swelling of the resist near the interface and X when the swelling occurred.

On the other hand, the reservoir of the unnecessary resist removing device EBR mounted on the TR-36000 is filled with each of the resist removing liquids shown in Table 1, and the base material is washed for 8 seconds, and then removed after 6 seconds. The portion was visually observed, and the drying property was evaluated as ○ when no remaining removal liquid was observed and as × when remaining removal liquid was observed. Table 1 shows the results.

[0025]

[Table 1] [Note] DPM: dipropylene glycol monomethyl ether BuAc: butyl acetate PGMEA: propylene glycol monomethyl ether acetate PGME: propylene glycol monomethyl ether

Continuation of the front page (72) Inventor Tetsuya Kato 150 Nakamaruko Nakahara-ku, Kawasaki City, Kanagawa Prefecture Inside Tokyo Ohka Kogyo Co., Ltd. (72) Inventor Koichi Takahashi 150 Nakamaruko Nakahara-ku Kawasaki City, Kanagawa Prefecture Tokyo Ohka Kogyo Co., Ltd. (56 References JP-A-9-308868 (JP, A) JP-A-7-84375 (JP, A) JP-A-4-3055653 (JP, A) Patent 2950407 (JP, B2) (58) Int.Cl. ⁷ , DB name) G03F 7/42 H01L 21/027

Claims (3)

(57) [Claims] 1. A method for forming a resist film by applying a resist-forming coating material to a substrate, wherein the coating material adheres to at least a part of a peripheral portion, an edge portion, and a back surface of the substrate before or after a drying process of a coating layer. A method for producing a substrate for electronic component production, comprising: removing an unnecessary coating layer or a resist film formed by drying the unnecessary coating layer with a resist removing solution consisting of only dipropylene glycol mono-lower alkyl ether, followed by drying treatment. . 2. A method for applying a resist-forming coating material to a substrate to form a resist film, wherein the coating film adheres to at least a part of a peripheral portion, an edge portion, and a back surface of the substrate before or after a drying process of a coating layer. An unnecessary coating layer or a resist film formed by drying the unnecessary coating layer has a dipropylene glycol mono-lower alkyl ether content of at least 65% by weight, with the remainder having a boiling point of 75 to 130 ° C and a vapor pressure at 20 ° C of 5 to 75 mmHg. A method for producing a substrate for producing an electronic component, comprising removing the substrate with a resist removing solution selected from a mixed solvent consisting of only a volatile organic solvent. 3. The method according to claim 2, wherein the volatile organic solvent having a boiling point of 75 to 130 ° C. and a vapor pressure at 20 ° C. of 5 to 75 mmHg is a lower alkyl acetate-based solvent.