TWI430025B - Photosensitive resin composition, interlayer insulating film, and method for processing microlens - Google Patents

Description

Method for producing radiation sensitive resin composition, interlayer insulating film and microlens

The present invention relates to a radiation sensitive resin composition and a method of manufacturing an interlayer insulating film and a microlens.

In an electronic product such as a thin film transistor (hereinafter referred to as "TFT") type liquid crystal display element, a magnetic head element, an integrated circuit element, or a solid-state image sensor, an interlayer insulating film for insulation is usually provided between the wirings arranged in layers. Since the material for forming the interlayer insulating film is preferably a material having a small number of steps required to obtain a necessary pattern shape and having sufficiently good flatness, the radiation sensitive resin composition is widely used (see Patent Document 1 and Patent Document 2).

In addition, as an optical system material of an on-chip color filter imaging optical system such as a facsimile machine, an electronic photocopier, or a solid-state image sensor, or an optical fiber connector, a microlens having a lens diameter of about 3 to 100 μm is used, or these microlenses are pressed. A regularly arranged microlens array. The formation of a microlens or a microlens array is known as a method of forming a resist pattern corresponding to a lens, directly flowing it as a lens after heat treatment, or using a melt flowing lens pattern as a mask. A method of transferring a lens shape to a bottom layer by dry etching or the like. In the formation of the above lens pattern, a radiation sensitive resin composition is widely used (see Patent Document 3 and Patent Document 4).

These interlayer insulating films and microlenses or microlens arrays are required to have various properties such as high heat resistance, high solvent resistance, high transparency, and adhesion to a primer layer. In addition, in the field of TFT liquid crystal display elements, in the field of large-screening, rapid response, and thinning, in recent years, as a composition for forming an interlayer insulating film used therein, it has high sensitivity and is formed. The interlayer insulating film has a low dielectric constant and requires higher performance than before. Further, in the process of manufacturing the interlayer insulating film and the microlens, in the developing step, if the development time is slightly more than the optimum time, the developer and the substrate are easily infiltrated into the developing solution to fall off, so that development must be strictly controlled. Time, therefore, it is necessary to develop a radiation sensitive resin composition having a sufficient development limit.

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2001-354822

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2001-343743

[Patent Document 3] Japanese Patent Laid-Open No. 6-187-2

[Patent Document 4] Japanese Patent Laid-Open No. Hei 6-136239

The present invention has been made based on the above circumstances. Accordingly, an object of the present invention is to provide a radiation sensitive composition which has high radiation sensitivity and excellent development limit, and can easily form a pattern-like film excellent in adhesion to a primer layer.

Another object of the present invention is to provide a radiation sensitive resin composition capable of forming an interlayer insulating film having high heat resistance, high solvent resistance, high light transmittance, and low dielectric constant when used for forming an interlayer insulating film. And when used to form a microlens, it is possible to form a microlens having high light transmittance and a good melt shape.

It is still another object of the present invention to provide a method of forming an interlayer insulating film and a microlens using the above-described radiation sensitive resin composition.

Other objects and advantages of the invention will be apparent from the description which follows.

According to the present invention, the above objects and advantages of the present invention, firstly achieved by a radiation sensitive resin composition, are characterized by comprising:

[A] contains (a1) at least one selected from the group consisting of unsaturated carboxylic acid and unsaturated carboxylic anhydride, and (a2) an unsaturated compound having an epoxy group and an oxetanyl group. a copolymer of at least one unsaturated mixture selected from the group consisting of saturated compounds (hereinafter also referred to as "copolymer (A)"),

[B] 1,2-quinonediazide compound (hereinafter also referred to as "[B] component"), and

[C] Silsesquinoxane having an aryl group having 6 to 15 carbon atoms (hereinafter also referred to as "[C] component").

According to the present invention, the above objects and advantages of the present invention, and secondly, are achieved by a method of forming an interlayer insulating film or a microlens, characterized by comprising the following steps in the following order,

(1) a step of forming a coating film of the above-mentioned radiation-sensitive resin composition on a substrate,

(2) a step of irradiating at least a part of the coating film with radiation,

(3) a step of developing the coated film after the irradiation, and

(4) A step of heating the developed coating film.

The radiation sensitive resin composition of the present invention has high radiation sensitivity and excellent development limit, and by using the radiation sensitive resin composition, a pattern-like film excellent in adhesion to the underlayer can be easily formed.

The interlayer insulating film of the present invention formed of the above composition is excellent in solvent resistance and heat resistance, has high light transmittance and low dielectric constant, and can be suitably used as an interlayer insulating film of an electronic product. Further, the microlens of the present invention formed of the above composition is excellent in solvent resistance and heat resistance, has high light transmittance and a good melt shape, and can be suitably used as a microlens of a solid-state image sensor.

Hereinafter, the radiation sensitive resin composition of the present invention will be described in detail.

Copolymer [A]

The copolymer [A] used in the present invention may be at least one selected from the group consisting of (a1) consisting of an unsaturated carboxylic acid and an unsaturated carboxylic anhydride (hereinafter also referred to as "compound (a1)") and (a2) an unsaturated mixture of at least one selected from the group consisting of an unsaturated compound having an epoxy group and an unsaturated compound having an oxetanyl group (hereinafter also referred to as "compound (a2)") It is produced by performing radical copolymerization in the presence of a polymerization initiator in a solvent.

The compound (a1) is a radically polymerizable unsaturated carboxylic acid and/or an unsaturated carboxylic anhydride, and examples thereof include monocarboxylic acids, dicarboxylic acids, dicarboxylic acid anhydrides, and polycarboxylic acids mono[(methyl). A propylene methoxyalkyl] ester, a mono(meth) acrylate of a polymer having a carboxyl group and a hydroxyl group at both terminals, a polycyclic compound having a carboxyl group, an acid anhydride thereof, and the like.

As a specific example, the monocarboxylic acid may, for example, be acrylic acid, methacrylic acid or crotonic acid; and the dicarboxylic acid may, for example, be maleic acid, fumaric acid, citraconic acid, mesaconic acid, itaconic acid or the like; Examples of the acid anhydride include an acid anhydride such as a compound exemplified as the above dicarboxylic acid; and a mono[(meth)acryloxyalkylalkyl] ester of a polyvalent carboxylic acid, for example, succinic acid mono [2-(methyl) Examples of the mono(meth)acrylate of a polymer having a carboxyl group and a hydroxyl group at both terminals may be exemplified by propylene methoxyethyl ethyl ester, phthalic acid mono [2-(methyl) propylene methoxyethyl] ester, and the like. For example, a mono(meth)acrylate of ω-carboxypolycaprolactone or the like; a polycyclic compound having a carboxyl group and an acid anhydride thereof may, for example, be 5-carboxybicyclo[2.2.1]hept-2-ene, 5,6 -Dicarboxybicyclo[2.2.1]hept-2-ene, 5-carboxy-5-methylbicyclo[2.2.1]hept-2-ene, 5-carboxy-5-ethylbicyclo[2.2. 1]hept-2-ene, 5-carboxy-6-methylbicyclo[2.2.1]hept-2-ene, 5-carboxy-6-ethylbicyclo[2.2.1]hept-2-ene, 5,6-Dicarboxybicyclo[2.2.1]hept-2-ene anhydride and the like.

Among them, an acid anhydride of a monocarboxylic acid or a dicarboxylic acid is preferably used, and acrylic acid, methacrylic acid, and maleic anhydride are particularly preferably used from the viewpoints of copolymerization reactivity, solubility to an alkali developing solution, and easy availability. These compounds (a1) may be used alone or in combination of two or more.

The compound (a2) is an unsaturated compound having an epoxy group and/or an unsaturated compound having an oxetanyl group, and as the unsaturated compound having an epoxy group, for example, glycidyl acrylate, A Glycidyl acrylate, glycidyl α-ethyl acrylate, glycidyl α-n-propyl acrylate, glycidyl α-n-butyl acrylate, 3,4-epoxy butyl acrylate Ester, 3,4-epoxybutyl methacrylate, -6,7-epoxyheptyl acrylate, -6,7-epoxyheptyl methacrylate, α-ethyl acrylate -6,7-epoxyheptyl ester,-3,4-epoxycyclohexyl acrylate,-3,4-epoxycyclohexyl methacrylate,-3,4-epoxy ring Hexylmethyl ester, 3,4-epoxycyclohexylmethyl methacrylate, o-vinylbenzyl glycidyl ether, m-vinylbenzyl glycidyl ether, p-vinylbenzyl glycidyl Ether, etc. Among them, glycidyl methacrylate and methacrylic acid-6,7-epoxy heptyl are preferably used from the viewpoint of improving copolymerization reactivity and heat resistance and surface hardness of the obtained interlayer insulating film or microlens. Ester, o-vinylbenzyl glycidyl ether, m-vinylbenzyl glycidyl ether, p-vinylbenzyl glycidyl ether, 3,4-epoxycyclohexyl methacrylate, methacrylic acid -3,4-epoxycyclohexylmethyl ester and the like.

Examples of the unsaturated compound having an oxetane group include 3-(acryloxymethyl)oxetane and 3-(acryloxymethyl)-2-methyloxirane. Butane, 3-(acryloxymethyl)-3-ethyloxetane, 3-(acryloxymethyl)-2-phenyloxetane, 3-(2- Propylene oxiranyl ethyl) oxetane, 3-(2-propenyloxyethyl)-2-ethyloxetane, 3-(2-propenyloxyethyl)-3 -Acrylate such as ethyloxetane or 3-(2-propenyloxyethyl)-2-phenyloxetane, 3-(methacryloxymethyl)oxycyclohexane Butane, 3-(methacryloxymethyl)-2-methyloxetane, 3-(methacryloxymethyl)-3-ethyloxetane, 3 -(methacryloxymethyl)-2-phenyloxetane, 3-(2-methylpropenyloxyethyl)oxetane, 3-(2-methylpropene醯oxyethyl)-2-ethyloxetane, 3-(2-methylpropenyloxyethyl)-3-ethyloxetane, 3-(2-methylpropene A methacrylate such as methoxyethyl)-2-phenyloxetane.

Among them, from the viewpoint of copolymerization reactivity, 3-(acryloxymethyl)-2-methyloxetane, 3-(acryloxymethyl)-3-ethyloxy is preferably used. Heterocyclobutane, 3-(methacryloxymethyl)-2-methyloxetane, 3-(methacryloxymethyl)-3-ethyloxetane Wait.

These compounds (a2) can be used singly or in combination.

The copolymer [A] used in the present invention is preferably a copolymer of the above compounds (a1), (a2) and further unsaturated compounds (hereinafter also referred to as "compound (a3)") which are copolymerizable with them. Things. The compound (a3) is not particularly limited as long as it is a radical polymerizable unsaturated compound, and examples thereof include an alkyl methacrylate, a cyclic alkyl methacrylate, and an alkyl acrylate. Ester, cyclic alkyl acrylate, aryl methacrylate, aryl acrylate, unsaturated dicarboxylic acid diester, methacrylate with hydroxyl group, bicyclic unsaturated compound, maleimide compound, Unsaturated aromatic compound, conjugated diene, unsaturated compound having a tetrahydrofuran skeleton, a furan skeleton, a tetrahydropyran skeleton, a pyran skeleton or a (poly)alkylene glycol skeleton, an unsaturated compound having a phenolic hydroxyl group, and the like Unsaturated compound.

As specific examples thereof, alkyl methacrylate may, for example, be methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, second butyl methacrylate or t-butyl methacrylate. 2-ethylhexyl methacrylate, isodecyl methacrylate, n-dodecyl methacrylate, tridecyl methacrylate, n-octadecyl methacrylate, etc.; The cyclic alkyl acrylate may, for example, be a cycloalkyl methacrylate, 2-methylcyclohexyl methacrylate or a tricyclo[5.2.1.0 ^2,6 ]decane-8-yl methacrylate (hereinafter referred to as Is "dicyclopentyl methacrylate"), tricyclo [5.0.1.02 ^2,6 ]decane-8-yloxyethyl methacrylate, isobornyl methacrylate, etc.; as alkyl acrylate For example, methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, second butyl acrylate, and tert-butyl acrylate may be mentioned; as the cyclic alkyl acrylate, for example, acrylic acid may be mentioned. Cyclohexyl ester, 2-methylcyclohexyl acrylate, tricyclohexyl acrylate [5.2.1. 0 ^2,6 ]decane-8-yl ester (hereinafter referred to as "dicyclopentyl acrylate"), tricyclo[5.2.1.0 ^2,6 ]decane-8-yloxyethyl ester, acrylic acid A borneol ester or the like; examples of the aryl acrylate include phenyl acrylate and benzyl acrylate; and examples of the aryl methacrylate include phenyl methacrylate and benzyl methacrylate; and the unsaturated dicarboxylic acid; The diester may, for example, be diethyl maleate, diethyl fumarate or diethyl itaconate. Examples of the methacrylate having a hydroxyl group include hydroxymethyl methacrylate and 2-methacrylic acid. Hydroxyethyl ester, 3-hydroxypropyl methacrylate, 4-hydroxybutyl methacrylate, diethylene glycol monomethacrylate, 2,3-dihydroxypropyl methacrylate, 2-methylpropene oxime Examples of the bicyclic unsaturated compound include, for example, bicyclo[2.2.1]hept-2-ene, 5-methylbicyclo[2.2.1]hept-2-ene, 5-ethyldi Ring [2.2.1]hept-2-ene, 5-hydroxybicyclo[2.2.1]hept-2-ene, 5-carboxybicyclo[2.2.1]hept-2-ene, 5-hydroxymethyl group Ring [2.2.1]hept-2-ene, 5-(2-hydroxyethyl) Ring [2.2.1] hept-2-ene and the like; as the maleimide compound, for example, N-phenylmaleimide, N-cyclohexylmaleimide, N-benzylmalanium Imine, N-(4-hydroxyphenyl)maleimide, N-(4-hydroxybenzyl)maleimide, N-succinimide-3-maleimidobenzene Formate, N-succinimide-4-maleimidobutyrate, N-succinimide-6-maleimidohexanoate, N-succinimide Benzyl-3-maleimidopropionate, N-(9-acridinyl)maleimide, and the like; examples of the unsaturated aromatic compound include styrene, α-methylstyrene, and Methylstyrene, p-methylstyrene, vinyltoluene, p-methoxystyrene, etc.; as the conjugated diene, for example, 1,3-butadiene, isoprene, 2,3-dimethyl Examples of the unsaturated compound having a tetrahydrofuran skeleton include tetrahydrofurfuryl (meth)acrylate, tetramethylammonium propionate, and tetrahydrofurfuryl propionate. 3-(methyl)propenyloxytetrahydrofuran-2-one; etc.; as an unsaturated compound having a furan skeleton For example, 2-methyl-5-(3-furyl)-1-penten-3-one, decyl (meth) acrylate, 1-furan-2-butyl-3-en-2-one , 1-furan-2-butyl-3-methoxy-3-en-2-one, 6-(2-furyl)-2-methyl-1-hexen-3-one, 6-furan -2-yl-hex-1-en-3-one, 2-furan-2-yl-1-methyl-ethyl acrylate, 6-(2-furyl)-6-methyl-1-heptane An ene-3-one or the like; as the unsaturated compound having a tetrahydropyran skeleton, for example, (tetrahydropyran-2-yl)methyl methacrylate and 2,6-dimethyl-8-(tetrahydrogen) Pyran-2-yloxy)-oct-1-en-3-one, 2-hydropyran-2-yl methacrylate, 1-(tetrahydropyran-2-yloxy)-butyl Alkyl-3-en-2-one or the like; as the unsaturated compound having a pyran skeleton, for example, 4-(1,4-dioxa-5-keto-6-heptenyl)-6-methyl -2-pyrone, 4-(1,5-dioxa-6-keto-7-octenyl)-6-methyl-2-pyranone, etc.; having a (poly)alkane skeleton Examples of the unsaturated compound include polyethylene glycol (n=2 to 10) mono(meth)acrylate, polypropylene glycol (n=2-10) mono(meth)acrylate, and the like; Saturated compounds can be enumerated (methyl) 4-hydroxybenzyl acrylate, 4-hydroxyphenyl (meth)acrylate, o-hydroxystyrene, p-hydroxystyrene, α-methyl-p-hydroxystyrene, N-(4-hydroxybenzyl) (methyl) Acrylamide, N-(3,5-dimethyl-4-hydroxybenzyl)(meth)acrylamide, N-(4-hydroxyphenyl)(meth)acrylamide, etc.; other Examples of the unsaturated compound include acrylonitrile, methacrylonitrile, vinyl chloride, vinylidene chloride, acrylamide, methacrylamide, and vinyl acetate.

Among them, alkyl methacrylate, cyclic alkyl methacrylate, cyclic alkyl acrylate, maleimide compound, unsaturated aromatic compound, conjugated diene, tetrahydrofuran skeleton, a furan skeleton, a tetrahydropyran skeleton, a pyran skeleton, an unsaturated compound of a (poly)alkane skeleton, and an unsaturated compound having a phenolic hydroxyl group, from the viewpoints of copolymerization reactivity and solubility in an aqueous alkali solution, Preferred is styrene, tert-butyl methacrylate, n-dodecyl methacrylate, tricyclo [5.1.07.2 ^2,6 ]decane-8-yl ester, p-methoxystyrene , 2-methylcyclohexyl acrylate, N-phenylmaleimide, N-cyclohexylmaleimide, 1,3-butadiene, tetrahydrofurfuryl (meth) acrylate, poly Ethylene glycol (n=2~10) mono(meth)acrylate, 3-(meth)acryloxytetrahydrofuran-2-one, 4-hydroxybenzyl (meth)acrylate, (meth)acrylic acid 4-hydroxyphenyl ester, o-hydroxystyrene, N-(4-hydroxyphenyl)(meth)acrylamide, p-hydroxystyrene, α-methyl-p-hydroxystyrene. These compounds (a3) may be used singly or in combination of two or more.

Preferred examples of the copolymer [A] used in the present invention include, for example, methacrylic acid/trimethyl methacrylate [5.2.1.0 ^2,6 ]decane-8-yl ester/2-methyl acrylate. Cyclohexyl ester/glycidyl methacrylate/styrene, methacrylic acid/tetrahydrofurfuryl methacrylate/glycidyl methacrylate/N-cyclohexylmaleimide/methacrylic acid Dialkyl ester / α-methyl-p-hydroxystyrene, styrene / methacrylic acid / glycidyl methacrylate / methacrylic acid (3-ethyloxetan-3-yl ester) / Tricyclomethacrylate [5.2.1.0 ^2,6 ]decane-8-yl ester, styrene/methacrylic acid/glycidyl methacrylate/N-(4-hydroxyphenyl)methacrylamide .

The copolymer [A] used in the present invention preferably contains 5 to 40% by weight of a repeat derived from the compound (a1) based on the total amount of the repeating units derived from the compounds (a1), (a2) and (a3). The unit preferably contains 5 to 25% by weight. If less than 5% by weight of the copolymer is used in the repeating unit, it is difficult to dissolve in the aqueous alkali solution in the developing step, and on the other hand, in the case of more than 40% by weight of the copolymer, the solubility in the aqueous alkali solution tends to be too large. .

Further, the copolymer [A] used in the present invention preferably contains 10 to 80% by weight of the derivative compound (a2) based on the total amount of the repeating units derived from the compounds (a1), (a2) and (a3). The repeating unit particularly preferably contains 30 to 80% by weight. When the repeating unit is less than 10% by weight, the heat resistance, surface hardness, and peeling resistance of the resulting interlayer insulating film or microlens tend to decrease. On the other hand, when the amount of the repeating unit exceeds 80% by weight However, there is a tendency that the storage stability of the radiation sensitive resin composition is lowered.

The polystyrene-equivalent weight average molecular weight (hereinafter referred to as "Mw") of the copolymer [A] used in the present invention is preferably 2 × 10 ³ to 1 × 10 ⁵ , more preferably 5 × 10 ³ to 5 ×. 10 ⁴ . On the other hand, if the Mw is less than 2 × 10 ³ , the development limit is insufficient, the residual film ratio of the obtained film is lowered, and the pattern shape and heat resistance of the obtained interlayer insulating film or microlens are deteriorated. If it exceeds 1 × 10 ⁵ , the sensitivity may decrease and the pattern shape may deteriorate. Further, the desired molecular weight distribution (hereinafter referred to as "Mw/Mn") is preferably 5.0 or less, more preferably 3.0 or less. If Mw/Mn exceeds 5.0, the pattern shape of the obtained interlayer insulating film or microlens may be deteriorated. The radiation sensitive resin composition containing the above copolymer [A] does not cause development residue during development, and can form a predetermined pattern shape easily.

The copolymer [A] can be synthesized, for example, by polymerizing the compound (a1), the compound (a2) and the compound (a3) in a suitable solvent in the presence of a radical polymerization initiator.

The solvent used in the preparation of the copolymer [A] may, for example, be diethylene glycol, propylene glycol monoalkyl ether, propylene glycol alkyl ether acetate, propylene glycol alkyl ether propionate, ketone or ester.

Specific examples thereof include, as diethylene glycol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diglyme, diethylene glycol diethyl ether, diethylene glycol ethyl methyl ether, and the like; Examples of the propylene glycol monoalkyl ether include propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, and propylene glycol monobutyl ether; and examples of the propylene glycol alkyl ether propionate include propylene glycol methyl ether propionate and propylene glycol. Ethyl ether propionate, propylene glycol propyl ether propionate, propylene glycol butyl ether propionate, etc.; as the propylene glycol alkyl ether acetate, for example, propylene glycol methyl ether acetate, propylene glycol ethyl ether acetate An ester, propylene glycol propyl ether acetate, propylene glycol butyl ether acetate or the like; examples of the ketone include methyl ethyl ketone, cyclohexanone, 4-hydroxy-4-methyl-2-pentanone; The ester may, for example, be methyl acetate, ethyl acetate, propyl acetate, butyl acetate, ethyl 2-hydroxypropionate, methyl 2-hydroxy-2-methylpropionate or 2-hydroxy-2-methyl. Ethyl propyl propionate, methyl hydroxyacetate, ethyl hydroxyacetate, butyl glycolate, milk Methyl ester, ethyl lactate, propyl lactate, butyl lactate, methyl methoxyacetate, ethyl methoxyacetate, methyl ethoxyacetate, ethyl ethoxyacetate, methyl propoxyacetate, Ethylpropoxyacetate, methyl butoxyacetate, ethyl butoxyacetate, methyl 2-methoxypropionate, ethyl 2-methoxypropionate, methyl 2-ethoxypropionate , 2-ethoxypropionate ethyl ester, methyl 2-butoxypropionate, ethyl 2-butoxypropionate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate , 3-methoxypropionic acid propyl ester, butyl 3-methoxypropionate, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, methyl 3-propoxypropionate An ester of ethyl 3-propoxypropionate, methyl 3-butoxypropionate or ethyl 3-butoxypropionate.

Among them, preferred are diethylene glycol dialkyl ether, propylene glycol monoalkyl ether, propylene glycol alkyl ether acetate, particularly preferably diglyme, diethylene glycol ethyl methyl ether, propylene glycol methyl ether. , propylene glycol ethyl ether, propylene glycol methyl ether acetate, methyl 3-methoxypropionate.

As the polymerization initiator used in the preparation of the copolymer [A], a polymerization initiator known as a radical polymerization initiator can be used. For example, 2,2'-azobisisobutyronitrile, 2,2'-azobis-(2,4-dimethylvaleronitrile), 2,2'-azobis-(4-methoxy) Azo compounds such as benzyl-2,4-dimethylvaleronitrile; benzammonium peroxide, laurel peroxide, t-butyl peroxypivalate, 1,1'-di (t-butyl Peroxidic) an organic peroxide such as cyclohexane; and hydrogen peroxide. When a peroxide is used as the radical polymerization initiator, it is also possible to use a peroxide together with a reducing agent as a redox type initiator.

In the preparation of the copolymer [A], a molecular weight modifier for adjusting the molecular weight can also be used. Specific examples thereof include halogenated hydrocarbons such as chloroform and carbon tetrabromide; and mercaptans such as n-hexyl mercaptan, n-octyl mercaptan, n-dodecyl mercaptan, tridodecanethiol, and mercaptoacetic acid; Xanthogen such as dimethylxanthogen sulfide or diisopropylxanthogen disulfide; terpinolene, α-methylstyrene dimer, and the like.

[B] ingredient

The component [B] used in the present invention is a 1,2-quinonediazide compound capable of generating a carboxylic acid by irradiation with radiation, and a phenolic compound or an alcoholic compound (hereinafter referred to as "mother core") and 1, may be used. A condensate of 2-naphthoquinonediazidesulfonium halide.

Examples of the mother nucleus include trihydroxybenzophenone, tetrahydroxybenzophenone, pentahydroxybenzophenone, hexahydroxybenzophenone, and (polyhydroxyphenyl)alkane.

As a specific example thereof, examples of the trihydroxybenzophenone include 2,3,4-trihydroxybenzophenone, 2,4,6-trihydroxybenzophenone, and the like; and as the tetrahydroxybenzophenone, for example, 2, 2',4,4'-tetrahydroxybenzophenone, 2,3,4,3'-tetrahydroxybenzophenone, 2,3,4,4'-tetrahydroxybenzophenone, 2,3,4, 2'-tetrahydroxy-4'-methylbenzophenone, 2,3,4,4'-tetrahydroxy-3'-methoxybenzophenone, etc.; as pentahydroxybenzophenone, for example, 2, 3 , 4,2',6'-pentahydroxybenzophenone, etc.; as the hexahydroxybenzophenone, for example, 2,4,6,3',4',5'-hexahydroxybenzophenone, 3,4, 5,3',4',5'-hexahydroxybenzophenone, etc.; as (polyhydroxyphenyl) alkane, for example, bis(2,4-dihydroxyphenyl)methane or bis(p-hydroxyphenyl)methane can be cited. , tris(p-hydroxyphenyl)methane, 1,1,1-tris(p-hydroxyphenyl)ethane, bis(2,3,4-trihydroxyphenyl)methane, 2,2-di(2,3 , 4-trihydroxyphenyl)propane, 1,1,3-tris(2,5-dimethyl-4-hydroxyphenyl)-3-phenylpropane, 4,4'-[1-[4- [1-[4-Hydroxyphenyl]-1-methylethyl]phenyl]ethylidene]bisphenol, bis(2,5-dimethyl-4-hydroxyphenyl)-2-hydroxyphenyl Methane 3,3,3',3'-tetramethyl-1,1'-spirobiguanidine-5,6,7,5',6',7'-hexaol, 2,2,4-trimethyl -7,2',4'-trihydroxyflavan, and the like.

Further, 1,2-naphthoquinonediazidesulfonamide such as 2,3,4-trihydroxybenzophenone-1 which is obtained by changing the ester bond of the parent core exemplified above to a guanamine bond can also be suitably used. , 2-naphthoquinonediazide-4-sulfonamide, and the like.

Among these mother cores, 2,3,4,4'-tetrahydroxybenzophenone, 4,4'-[1-[4-[1-[4-hydroxyphenyl]-1-methyl-B is preferred Phenyl]ethylidene]bisphenol.

Further, as the 1,2-naphthoquinonediazidesulfonium halide, for example, 1,2-naphthoquinonediazidesulfonium chloride is preferable, and as a specific example thereof, 1,2-naphthoquinonediazide- 4-sulfonium chloride and 1,2-naphthoquinonediazide-5-sulfonyl chloride, among which 1,2-naphthoquinonediazide-5-sulfonyl chloride is preferably used.

In the condensation reaction, it is preferred to use a 1,2-naphthoquinone stack corresponding to 30 to 85 mol%, more preferably 50 to 70 mol%, based on the number of OH groups in the phenolic compound or the alcohol compound. Nitrosulfuronium halide.

The condensation reaction can be carried out by a known method.

These [B] components may be used alone or in combination of two or more.

The use ratio of the component [B] is preferably 5 to 100 parts by weight, more preferably 10 to 50 parts by weight, per 100 parts by weight of the copolymer [A]. When the ratio is less than 5 parts by weight, the difference in solubility between the portion irradiated with radiation and the portion not irradiated with radiation with respect to the aqueous alkali solution as the developing solution is small, a case where pattern formation is difficult, and the resulting interlayer insulating film may occur. Or the heat resistance and solvent resistance of the microlens are not good enough. On the other hand, when the ratio exceeds 100 parts by weight, the solubility of the irradiated portion in the aqueous alkali solution described above is not sufficiently large, and development may be difficult.

[C] component

The component [C] used in the present invention is a sesquioxane having a aryl group having 6 to 15 carbon atoms. By including such a component in the radiation-sensitive resin composition, a radiation-sensitive resin composition having high radiation sensitivity and excellent development limit can be obtained, and an interlayer dielectric film having a low dielectric constant can be formed, and at the same time, it can be formed. An interlayer insulating film or microlens excellent in adhesion to the underlayer.

The component [C] can be produced, for example, by hydrolyzing a decane compound represented by the following formula (1) (hereinafter also referred to as "compound (c1)").

Si(R ¹ )(OR ² )(OR ³ )(OR ⁴ ) (1)

(wherein R ¹ represents an aryl group having 6 to 15 carbon atoms, and R ² to R ⁴ each independently represent a hydrogen atom or a substituted or unsubstituted alkyl group or a fluorenyl group having 1 to 4 carbon atoms).

The above hydrolyzate is understood to include a hydrolyzate in which the hydrolyzable portion of the raw material is completely hydrolyzed, and a hydrolyzate in which a part thereof is hydrolyzed and a part is not hydrolyzed.

The above-described formula (1), the carbon atoms of R ¹ is an aryl group having 6 to 15 include naphthyl, phenyl, anthryl, phenanthryl, benzyl group, preferably a phenyl group or a benzyl group, Laid Good is phenyl.

Specific examples of the compound (c1) include phenyltrimethoxydecane, phenyltriethoxydecane, phenyltri-n-propoxydecane, phenyltriisopropoxydecane, and phenyltriethoxycarbonyl. Base decane, phenyl tris(methoxyethoxy) decane, and the like.

Among them, phenyltrimethoxydecane and phenyltriethoxydecane are preferred from the viewpoint of reactivity and storage stability. The compound (c1) may be used singly or in combination of two or more.

The component [C] used in the present invention is preferably a compound (c1) and a decane compound represented by the following formula (2) from the viewpoint of the development limit and the adhesion of the obtained cured film (hereinafter also referred to as "compound (c2). a hydrolysis condensate of ").

Si(R ⁵ )(OR ⁶ )(OR ⁷ )(OR ⁸ ) (2)

(wherein R ⁵ is an alkyl group having 1 to 15 carbon atoms, and R ⁶ to R ⁸ are each independently a hydrogen atom or a substituted or unsubstituted alkyl group or a fluorenyl group having 1 to 4 carbon atoms). In the above formula (2), the alkyl group having 1 to 15 carbon atoms is preferably a linear or branched alkyl group having 1 to 6 carbon atoms or a cycloalkane having 5 to 10 carbon atoms. base. More preferably, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, cyclopentyl, cyclohexyl, adamantyl, isobornyl, tricyclodecyl, etc., particularly preferably methyl.

Specific examples of the compound (c2) include methyltrimethoxydecane, methyltriethoxydecane, methyltri-n-propoxydecane, methyltriisopropoxydecane, and methyltriethoxysilane. Base decane, methyl tris (methoxyethoxy) decane, ethyl trimethoxy decane, ethyl triethoxy decane, ethyl tri-n-propoxy decane, ethyl triisopropoxy decane, B Triethyl decyloxydecane, ethyl tris(methoxyethoxy)decane, n-propyltrimethoxydecane, n-propyltriethoxydecane, n-propyltri-n-propoxydecane, n-propyl Triisopropoxy decane, n-propyltriethoxydecane, n-propyltris(methoxyethoxy)decane, cyclohexyltrimethoxydecane, cyclohexyltriethoxydecane, cyclohexyl N-propoxydecane, cyclohexyltriisopropoxydecane, cyclohexyltriethoxydecane, cyclohexyltris(methoxyethoxy)decane, and the like.

Among them, methyltrimethoxydecane and methyltriethoxydecane are preferred from the viewpoint of reactivity and storage stability. The compound (c2) may be used singly or in combination of two or more.

The component [C] used in the present invention preferably contains 50% by weight or more of a repeating unit derived from the compound (c1), more preferably 50%, based on the total amount of the repeating units derived from the compounds (c1) and (c2). 95% by weight, particularly preferably 60 to 90% by weight. If the repeating unit is less than 50% by weight, the radiation-sensitive resin composition may be phase-separated from the copolymer [A] to hinder the formation of a coating film.

The hydrolysis reaction for preparing the component [C] is preferably carried out in a suitable solvent. As such a solvent, for example, methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, tert-butanol, acetone, methyl ethyl ketone, methyl isobutyl ketone, propylene glycol alone may be mentioned. A water-soluble solvent such as methyl ether, propylene glycol methyl ether acetate, tetrahydrofuran, dioxane or acetonitrile or an aqueous solution thereof.

Since these water-soluble solvents are to be removed in the subsequent step, it is preferred that methanol, ethanol, n-propanol, isopropanol, acetone, methyl ethyl ketone, methyl isobutyl ketone, tetrahydrofuran, etc. have a lower boiling point. The solvent is more preferably a ketone such as acetone, methyl ethyl ketone or methyl isobutyl ketone, and particularly preferably methyl isobutyl ketone, from the viewpoint of solubility of the raw material.

Further, the hydrolysis reaction is preferably carried out in an acid catalyst such as hydrochloric acid, sulfuric acid, nitric acid, formic acid, oxalic acid, acetic acid, trifluoroacetic acid, trifluoromethanesulfonic acid, acidic ion exchange resin, various Lewis acids, or a base catalyst such as ammonia, first grade. Amines, secondary amines, tertiary amines, nitrogen-containing aromatic compounds such as pyridine, basic ion exchange resins, hydroxides such as sodium hydroxide, carbonates such as potassium carbonate, and carboxylates such as sodium acetate, various types of Louis It is carried out in the presence of a base or the like. The amount of the catalyst used is preferably 0.2 mol or less, more preferably 0.00001 to 0.1 mol, based on 1 mol of the monomer.

The water content, the reaction temperature, and the reaction time can be appropriately set. For example, the following conditions can be employed.

The content of water is 1.5 mol or less, preferably 1 mol or less, more preferably 0.9 mol or less, based on 1 mol of the total of hydrolyzable groups in the decane compound used in the preparation.

The reaction temperature is preferably from 40 to 200 ° C, more preferably from 50 to 150 ° C. The reaction time is preferably from 30 minutes to 24 hours, more preferably from 1 to 12 hours.

The polystyrene-equivalent weight average molecular weight of the component [C] used in the present invention is preferably 5 × 10 ² to 5 × 10 ³ , more preferably 1 × 10 ³ to 4.5 × 10 ³ . If the weight average molecular weight of the component [C] is less than 5 × 10 ² , there is a possibility that the development limit is insufficient. On the other hand, if it exceeds 5 × 10 ³ , it exists in the radiation sensitive resin composition and the copolymer [A]. Phase separation occurs to hinder the formation of a coating film.

The use ratio of the component [C] is preferably 10 to 100 parts by weight, more preferably 15 to 50 parts by weight, per 100 parts by weight of the copolymer [A]. When the use ratio is less than 10 parts by weight, there is a possibility that the desired effect cannot be obtained. On the other hand, when it exceeds 100 parts by weight, there is a possibility of phase separation from the copolymer [A] to hinder the formation of a coating film. .

Other ingredients

The radiation sensitive resin composition of the present invention contains the above-mentioned copolymer [A], [B], and [C] as essential components, and may contain [D] heat-sensitive acid-producing compound and [E] as needed. At least one polymerizable compound having an ethylenically unsaturated double bond, an epoxy resin other than the [F] copolymer [A], a [G] surfactant, or a [H] adhesion aid.

The above [D] heat-sensitive acid generating compound can be used for the purpose of improving heat resistance and hardness. Specific examples thereof include known onium salts such as an onium salt, a benzothiazolium salt, an ammonium salt, and a phosphonium salt.

The use ratio of the component [D] is preferably 20 parts by weight or less, more preferably 5 parts by weight or less based on 100 parts by weight of the copolymer [A]. When the amount used exceeds 20 parts by weight, precipitates may be precipitated in the coating film forming step, and the formation of the coating film may be hindered.

The polymerizable compound containing at least one ethylenically unsaturated double bond as the component [E] is preferably, for example, a known monofunctional (meth) acrylate, difunctional (meth) acrylate or trifunctional or higher. (Meth) acrylate. Among them, it is preferred to use a trifunctional or higher (meth) acrylate, particularly preferably trimethylolpropane tri(meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate. .

The use ratio of the component [E] is preferably 50 parts by weight or less, more preferably 30 parts by weight or less based on 100 parts by weight of the copolymer [A].

By including the [E] component in such a ratio, heat resistance, surface hardness, and the like of the interlayer insulating film or the microlens obtained from the radiation sensitive resin composition of the present invention can be improved. If the amount used exceeds 50 parts by weight, a film splitting may occur in the step of forming a coating film of the radiation sensitive resin composition on the substrate.

The epoxy resin other than the copolymer [A] of the above [F] component is not limited as long as it does not affect the compatibility. Preferred examples thereof include bisphenol A type epoxy resin, phenol novolak type epoxy resin, cresol novolac type epoxy resin, cyclic aliphatic epoxy resin, glycidyl ester type epoxy resin, glycidyl amine type epoxy resin. Resin, heterocyclic epoxy resin, resin (co)polymerized with glycidyl methacrylate, and the like. Among them, a bisphenol A type epoxy resin, a cresol novolac type epoxy resin, a glycidyl ester type epoxy resin, and the like are particularly preferable.

The use ratio of the component [F] is preferably 30 parts by weight or less based on 100 parts by weight of the copolymer [A]. By containing the [F] component in such a ratio, the heat resistance, surface hardness, and the like of the protective film or the insulating film obtained from the radiation sensitive resin composition of the present invention can be further improved. If the ratio exceeds 30 parts by weight, when the radiation-sensitive resin composition coating film is formed on the substrate, the film thickness uniformity of the coating film may be insufficient.

Further, the copolymer [A] may also be referred to as "epoxy resin", but it is different from the [F] component in that it has alkali solubility. The [F] component is alkali-insoluble.

In the radiation sensitive resin composition of the present invention, in order to further improve the coatability, a surfactant as the above [G] component can also be used. As the [G] surfactant, for example, a fluorine-based surfactant or a siloxane-based surfactant can be preferably used.

Specific examples of the fluorine-based surfactant include 1,1,2,2-tetrafluorooctyl (1,1,2,2-tetrafluoropropyl)ether and 1,1,2,2-tetrafluoro. Octyl hexyl ether, octaethylene glycol di(1,1,2,2-tetrafluorobutyl)ether, hexaethylene glycol (1,1,2,2,3,3-hexafluoropentyl)ether, Octapropylene glycol bis(1,1,2,2-tetrafluorobutyl)ether, hexapropylene glycol bis(1,1,2,2,3,3-hexafluoropentyl)ether, perfluorododecyl sulfonic acid Sodium, 1,1,2,2,8,8,9,9,10,10-decafluorododecane, 1,1,2,2,3,3-hexafluorodecane, etc. Further, sodium fluoroalkylbenzenesulfonate, fluoroalkyloxyethylene ether, fluoroalkylammonium iodide, fluoroalkyl polyoxyethylene ether, perfluoroalkyl polyoxyethylene, perfluoroalkane An alkyl alkoxide, a fluorine-based alkyl ester or the like. As such commercial products, BM-1000, BM-1100 (above, produced by BM Chemie), Megafac F142D, Megafac F172, Megafac F173, Megafac F183, Megafac F178, Megafac F191, Megafac F471 (above, Dainippon Ink Chemical Industry Co., Ltd.), Fluorad FC-170C, FC-171, FC-430, FC-431 (above, produced by Sumitomo 3M), Surflon S-112, Surflon S-113, Surflon S-131, Surflon S-141, Surflon S-145, Surflon S-382, Surflon SC-101, Surflon SC-102, Surflon SC-103, Surflon SC-104, Surflon SC-105, Surflon SC-106 (Asahi Glass) (share) production), Eftop EF 301, Eftop EF 303, Eftop EF 352 (new Akita Chemicals Co., Ltd. production).

Examples of the above-mentioned oxoxane-based surfactant include DC3PA, DC7PA, FS-1265, SF-8428, SH11PA, SH21PA, SH28PA, SH29PA, SH30PA, SH-190, SH-193, and SZ-6032 (above, Oxygen sold by Toray Dowcorning Silicone Co., TSF-4440, TSF-4300, TSF-4445, TSF-4446, TSF-4460, TSF-4452 (produced by GE Toshiba Silicon Co., Ltd.) Alkane surfactant.

These surfactants may be used singly or in combination of two or more. These [G] surfactants are preferably used in an amount of 5 parts by weight or less, more preferably 2 parts by weight or less based on 100 parts by weight of the copolymer [A]. When the amount of the [G] surfactant to be used exceeds 5 parts by weight, when the coating film is formed on the substrate, the coating film is likely to be cleaved.

Further, in order to improve the adhesion to the substrate, a binder auxiliary [H] component can also be used in the radiation sensitive resin composition of the present invention. As such a [H] adhesion aid, a functional decane coupling agent is preferably used, and examples thereof include a decane coupling agent having a reactive substituent such as a carboxyl group, a methacryl group, an isocyanate group or an epoxy group. Specific examples thereof include trimethoxydecyl benzoate, γ-methacryloxypropyltrimethoxydecane, vinyltriethoxydecane, vinyltrimethoxydecane, and γ-isocyanatepropyl. Triethoxy decane, γ-glycidoxypropyltrimethoxydecane, β-(3,4-epoxycyclohexyl)ethyltrimethoxydecane, and the like. The [H] adhesion aid is preferably used in an amount of 20 parts by weight or less, more preferably 10 parts by weight or less based on 100 parts by weight of the copolymer [A]. When the amount of the binder auxiliary exceeds 20 parts by weight, there is a case where development residue easily occurs in the developing step.

Radiation-sensitive resin composition

The radiation sensitive resin composition of the present invention can be prepared by uniformly mixing the above copolymer [A], [B] and [C] components and other components optionally added as described above. The radiation sensitive resin composition of the present invention is preferably used in the form of a solution dissolved in a suitable solvent. For example, a radiation-sensitive resin composition in a solution state can be prepared by mixing the copolymer [A], [B], and [C] components and optionally other components in a predetermined ratio.

As the solvent used in the preparation of the radiation sensitive resin composition of the present invention, each of the components which can uniformly dissolve the copolymer [A], [B] and [C] components and optionally other components can be used, and The solvent for the reaction of each component.

As such a solvent, the same solvent as exemplified above as a solvent which can be used in the production of the copolymer [A] can be mentioned.

In such a solvent, alcohol, glycol ether, ethylene glycol alkyl ether acetate, or the like is preferably used from the viewpoints of solubility of each component, reactivity with each component, easiness of formation of a coating film, and the like. Ester and diethylene glycol. Among them, benzyl alcohol, 2-phenylethyl alcohol, 3-phenyl-1-propanol, ethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol can be used. Diethyl ether, diethylene glycol ethyl methyl ether, diglyme, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, methyl methoxypropionate, ethyl ethoxy propionate.

In order to increase the in-plane uniformity of the film thickness, a high boiling point solvent may be further used in combination with the above solvent. Examples of the high boiling point solvent which can be used in combination include N-methylformamide, N,N-dimethylformamide, N-methylformamide, N-methylacetamide, N,N. - dimethyl acetamide, N-methylpyrrolidone, dimethyl hydrazine, benzyl ethyl ether, dihexyl ether, acetonyl acetone, isophorone, hexanoic acid, octanoic acid, 1-octanol, 1 - decyl alcohol, benzyl acetate, ethyl benzoate, diethyl oxalate, diethyl maleate, γ-butyrolactone, ethylene carbonate, propylene carbonate, phenyl cellosolve acetate, etc. . Among them, preferred are N-methylpyrrolidone, γ-butyrolactone, and N,N-dimethylacetamide.

When the solvent of the radiation sensitive linear resin composition of the present invention is used in combination with a high boiling point solvent, the amount thereof may be 50% by weight or less, preferably 40% by weight or less, more preferably 30% by weight or less based on the total amount of the solvent. . When the amount of the high-boiling solvent exceeds this amount, there is a case where the film thickness uniformity, the sensitivity, and the residual film ratio are lowered.

When the radiation sensitive resin composition of the present invention is formulated into a solution state, the total of the components other than the solvent in the solution (i.e., the copolymer [A], [B], and [C] components, and optionally other components are added in total. The proportion of the amount can be arbitrarily set depending on the purpose of use, the desired film thickness value, and the like. Even so, it is preferably 5 to 50% by weight, more preferably 10 to 40% by weight, still more preferably 15 to 35% by weight.

The composition solution thus prepared can also be filtered and applied to a micropore filter having a pore size of about 0.2 μm.

Formation of interlayer insulating film and microlens

Next, a method of forming the interlayer insulating film and the microlens of the present invention using the radiation sensitive resin composition of the present invention will be described. The method of forming the interlayer insulating film or the microlens of the present invention includes the following steps in the following order.

(1) a step of forming a coating film of the radiation sensitive resin composition of the present invention on a substrate,

(2) a step of irradiating at least a part of the coating film with radiation,

(3) a step of developing the coated film after the irradiation, and

(4) A step of heating the developed coating film.

(1) Step of forming a coating film of the radiation sensitive resin composition of the present invention on a substrate

In the above step (1), the composition solution of the present invention is applied onto the surface of the substrate, and it is preferred to remove the solvent by prebaking to form a coating film of the radiation sensitive resin composition.

Examples of the type of the substrate that can be used include a glass substrate, a tantalum wafer, and a substrate on which various metals are formed on the surface.

The coating method of the composition solution is not particularly limited, and may be, for example, a spray coating method, a roll coating method, a spin coating method (spin coating method), a slit die coating method, a bar coating method, an inkjet method, or the like. The method is particularly preferably a spin coating method or a slit die coating method. The conditions for prebaking differ depending on the type of each component, the ratio of use, and the like. For example, it can be carried out at 60 to 110 ° C for about 30 seconds to 15 minutes.

The thickness of the formed coating film is preferably, for example, 3 to 6 μm when the interlayer insulating film is formed, and preferably 0.5 to 3 μm when the microlens is formed.

(2) a step of irradiating at least a part of the coating film with radiation

In the above step (2), the formed coating film is irradiated with radiation through a mask having a predetermined pattern, and then developed by a developing solution to remove a portion irradiated with radiation to form a pattern. Examples of the radiation used at this time include ultraviolet rays, far ultraviolet rays, X-rays, charged particle beams, and the like.

Examples of the ultraviolet rays include a g line (wavelength: 436 nm), an i line (wavelength: 365 nm), and the like. Examples of the far ultraviolet rays include KrF excimer lasers and the like. Examples of the X-rays include synchronous acceleration radiation and the like. Examples of the charged particle beam include an electron beam and the like.

Among them, ultraviolet rays are preferred, and radiation containing g-line and/or i-line is particularly preferred.

As the amount of exposure, when the interlayer insulating film, is preferably 50 ~ 1500J / m ^2, when the microlenses are formed, it is preferably 50 ~ 2000J / m ^2.

(3) Development step

As the developer used in the development treatment, for example, sodium hydroxide, potassium hydroxide, sodium carbonate, sodium citrate, sodium metasilicate, ammonia, tetramethylammonium hydroxide, tetraethylammonium hydroxide, pyrrole, or the like can be used. Alkaloids such as acridine, 1,8-diazabicyclo[5.4.0]-7-undecene, 1,5-diazabicyclo[4.3.0]-5-decane An aqueous solution. Further, an appropriate amount of an aqueous solution of a water-soluble organic solvent such as methanol or ethanol or a surfactant, or various organic solvents in which the composition of the present invention is dissolved may be added to the aqueous alkali solution as a developing solution. Further, as the developing method, an appropriate method such as a liquid-filling method, a dipping method, a shaking dipping method, or a rinsing method can be employed. The development time at this time varies depending on the composition of the composition, and may be, for example, 30 to 120 seconds.

Further, in the previously known radiation sensitive resin composition, if the development time exceeds the optimum value by more than 20 to 25 seconds, the formed pattern may fall off, so that the development time must be strictly controlled, and the feeling for the present invention is In the case of the radiation-linear resin composition, even if the time exceeding the optimum development time reaches 30 seconds or more, a good pattern can be formed, which is advantageous in terms of product yield.

(4) Heating step

After the (3) development step is performed as described above, the patterned film is preferably subjected to a rinsing treatment such as running water cleaning, and it is preferable to perform full-radiation irradiation (post-exposure) using a high-pressure mercury lamp or the like, and the residual 1 in the film The 2-quinonediazide compound is subjected to a decomposition treatment, and then the film is subjected to a heat treatment (post-baking treatment) by a heating means such as a hot plate or an oven to cure the film. The exposure amount in the above post-exposure step is preferably about 2,000 to 5,000 J/m ² . Further, the baking temperature in the curing treatment is, for example, 120 to 250 °C. The heating time varies depending on the type of the heating machine. For example, when heat treatment is performed on the hot plate, it may be 5 to 30 minutes, and when heat treatment is performed in an oven, it may be 30 to 90 minutes. At this time, a stepwise baking method or the like which performs two or more heating steps may also be employed. Thus, a pattern-like film corresponding to the target interlayer insulating film or microlens can be formed on the surface of the substrate.

The interlayer insulating film and the microlens formed as described above are excellent in dielectric constant, adhesion, heat resistance, solvent resistance, transparency, and the like, as described in the following examples.

Interlayer insulating film

The interlayer insulating film of the present invention formed as described above has a low dielectric constant, good adhesion to a substrate, excellent solvent resistance and heat resistance, high light transmittance, and can be suitably used as an interlayer insulating film for an electronic product.

Microlens

The microlens of the present invention formed as described above is excellent in adhesion to a substrate, excellent in solvent resistance and heat resistance, and has high light transmittance and a good melt shape, and can be suitably used as a microlens of a solid-state image sensor. Further, the shape of the microlens of the present invention is a semiconvex lens shape as shown in Fig. 1(a).

[Examples]

Hereinafter, the present invention will be more specifically described by way of examples of synthesis and examples, but the present invention is not limited to the following examples.

Synthesis example of copolymer [A] Synthesis Example 1

To a flask equipped with a cooling tube and a stirrer, 7 parts by weight of 2,2'-azobis(2,4-dimethylvaleronitrile) and 200 parts by weight of diethylene glycol ethyl methyl ether were added. Continue to add 16 parts by weight of methacrylic acid, 14 parts by weight of tricyclo [5.2.1.0 ^2,6 ]decane-8-yl methacrylate, 20 parts by weight of 2-methylcyclohexyl acrylate, 40 parts by weight of methyl Glycidyl acrylate, 10 parts by weight of styrene, and 3 parts by weight of α-methylstyrene dimer were slowly stirred after replacement with nitrogen. The temperature of the solution was raised to 70 ° C, and the temperature was maintained for 4 hours to obtain a polymer solution containing the copolymer [A-1]. The copolymer [A-1] had a polystyrene-equivalent weight average molecular weight (Mw) of 8,000 and a molecular weight distribution (Mw/Mn) of 2.3. Further, the polymer solution prepared herein had a solid content concentration of 34.4% by weight.

Synthesis Example 2

To a flask equipped with a cooling tube and a stirrer, 8 parts by weight of 2,2'-azobis(2,4-dimethylvaleronitrile) and 220 parts by weight of diethylene glycol ethyl methyl ether were added. Continue to add 13 parts by weight of methacrylic acid, 12 parts by weight of tetrahydrofurfuryl methacrylate, 40 parts by weight of glycidyl methacrylate, 15 parts by weight of N-cyclohexylmaleimide, 10 parts by weight of methyl Dodecyl acrylate, 10 parts by weight of α-methyl-p-hydroxystyrene, and 3 parts by weight of α-methylstyrene dimer were slowly stirred after replacement with nitrogen. The temperature of the solution was raised to 70 ° C, and the temperature was maintained for 5 hours to obtain a polymer solution containing the copolymer [A-2].

The copolymer [A-2] had a polystyrene-equivalent weight average molecular weight (Mw) of 8,000 and a molecular weight distribution (Mw/Mn) of 2.3. Further, the polymer solution prepared herein had a solid content concentration of 31.9% by weight.

Synthesis Example 3

To a flask equipped with a cooling tube and a stirrer, 8 parts by weight of 2,2'-azobis(2,4-dimethylvaleronitrile) and 220 parts by weight of diethylene glycol ethyl methyl ether were added. 10 parts by weight of styrene, 20 parts by weight of methacrylic acid, 40 parts by weight of glycidyl methacrylate, 10 parts by weight of (3-ethyloxetan-3-yl methacrylate) and 20 are continuously added. The tricyclo[5.2.1.0 ^2,6 ]decane-8-yl methacrylate was added in portions by weight, and then slowly stirred. The temperature of the solution was raised to 70 ° C, and the temperature was maintained for 5 hours to obtain a polymer solution containing the copolymer [A-3].

The polystyrene-equivalent weight average molecular weight (Mw) of the copolymer [A-3] was 7,900, and the molecular weight distribution (Mw/Mn) was 2.4. Further, the polymer solution prepared herein had a solid content concentration of 31.6% by weight.

Synthesis Example 4

To a flask equipped with a cooling tube and a stirrer, 8 parts by weight of 2,2'-azobis(2,4-dimethylvaleronitrile) and 220 parts by weight of diethylene glycol ethyl methyl ether were added. 15 parts by weight of styrene, 15 parts by weight of methacrylic acid, 45 parts by weight of glycidyl methacrylate, and 20 parts by weight of N-(4-hydroxyphenyl)-methacrylamide were continuously added, and after replacing with nitrogen, An additional 5 parts by weight of 1,3-butadiene was added and stirring was started slowly. The temperature of the solution was raised to 70 ° C, and the temperature was maintained for 5 hours to obtain a polymer solution containing the copolymer [A-4].

The copolymer [A-4] had a polystyrene-equivalent weight average molecular weight (Mw) of 7,900 and a molecular weight distribution (Mw/Mn) of 2.4. Further, the polymer solution prepared herein had a solid content concentration of 31.5% by weight.

Synthesis of [C] component Synthesis Example 5

100 g of phenyltrimethoxydecane was placed in a 500 ml three-necked flask, dissolved in 100 g of methyl isobutyl ketone, and heated to 60 ° C while stirring with a magnetic stirrer. To the solution, 8.6 g of ion-exchanged water in which 1% by weight of oxalic acid was dissolved was continuously added over 1 hour. After the temperature of the solution was maintained at 60 ° C for 4 hours, the resulting reaction solution was cooled to room temperature. Then, the reaction by-product alcohol component was removed from the reaction liquid by distillation under reduced pressure. The sesquiterpene oxide [C-1] thus obtained had a weight average molecular weight of 1,600.

Synthesis Example 6

79.8 g of phenyltrimethoxydecane and 21.2 g of methyltrimethoxydecane were placed in a 500 ml three-necked flask, and 100 g of propylene glycol methyl ether acetate was added thereto to dissolve, and the mixture was heated while stirring with a magnetic stirrer. 60 ° C. To the solution, 8.6 g of ion-exchanged water in which 1% by weight of oxalic acid was dissolved was continuously added over 1 hour. After the temperature of the solution was maintained at 60 ° C for 4 hours, the resulting reaction solution was cooled to room temperature. Then, the reaction by-product alcohol component was removed from the reaction liquid by distillation under reduced pressure. The sesquioxane [C-2] thus obtained had a weight average molecular weight of 2,000.

Example 1 [Preparation of radiation sensitive resin composition]

100 parts by weight (in terms of solid content) of the copolymer [A-1] synthesized in the above Synthesis Example 1 as the component [A], and 4,4'-[1-[4-[1] as the component [B] -[4-Hydroxyphenyl]-1-methylethyl]phenyl]ethylidene]bisphenol (1.0 mol) and 1,2-naphthoquinonediazide-5-sulfonyl chloride (2.0 mol) 30 parts by weight of the condensate (B-1) and 30 parts by weight of sesquiterpene oxide [C-1] (in terms of solid content) are mixed and dissolved in diethylene glycol ethyl methyl ether. The solid content concentration was 30% by weight, and then filtered through a filter having a pore size of 0.2 μm to prepare a solution (S-1) of a radiation-sensitive resin composition.

Examples 2 to 8 and Comparative Example 1 [Preparation of radiation sensitive resin composition]

In the first embodiment, a solution of the radiation sensitive linear resin composition was prepared in the same manner as in Example 1 except that the components (A) and [C] were used in the same manner as in Table 1. )~(S-8) and (s-1).

Further, in Examples 2, 4, 6, and 8, the elements listed in the [B] component were used in combination with two 1,2-quinonediazide compounds, respectively.

Example 9

In Example 1, it was dissolved in ethylene glycol ethyl methyl ether / propylene glycol monomethyl ether acetate = 6 / 4 to have a solid content concentration of 20% by weight, and a rhodium-based surfactant SH was added. A composition was prepared in the same manner as in Example 1 except that -28PA (manufactured by Toray Dow Corning Co., Ltd.) was used to prepare a radiation-sensitive resin composition solution (S-9).

In Table 1, the abbreviations of the components represent the following compounds.

B-1: 4,4'-[1-[4-[1-[4-hydroxyphenyl]-1-methylethyl]phenyl]ethylidene]bisphenol (1.0 mol) and 1, Condensate of 2-naphthoquinonediazide-5-sulfonyl chloride (2.0 mol)

B-2: 4,4'-[1-[4-[1-[4-hydroxyphenyl]-1-methylethyl]phenyl]ethylidene]bisphenol (1.0 mol) and 1, Condensate of 2-naphthoquinonediazide-5-sulfonyl chloride (1.0 mol)

F: a decane-based surfactant (trade name: SH-28PA, manufactured by Toray Dow Corning Silicone Co.).

Examples 10 to 18 and Comparative Example 2 <Performance evaluation as interlayer insulating film>

Using the radiation sensitive resin composition prepared as above, various properties as an interlayer insulating film were evaluated as follows.

[Evaluation of sensitivity]

For Examples 10 to 17, and Comparative Example 2, the compositions listed in Table 2 were applied onto a ruthenium substrate by a spin coater, and then prebaked on a hot plate at 90 ° C for 2 minutes to form a film thickness of 3.0. Μm coating film. For Example 18, coating was carried out using a slit die coater, vacuum drying was carried out at 0.5 Torr, and prebaking was carried out at 90 ° C for 2 minutes on a hot plate to form a coating film having a film thickness of 3.0 μm. The exposure time was changed by using a PLA-501F exposure machine (ultra-high pressure mercury lamp) manufactured by Canon through a pattern mask having a predetermined pattern, and after exposure to the obtained coating film, the concentration of tetramethyl hydroxide shown in Table 2 was observed. The aqueous solution of the ammonium chloride was developed by a liquid-filling method at 25 ° C, developed for 80 seconds when a developer having a concentration of 0.4% was used, and developed for 50 seconds when a developer having a concentration of 2.38% was used. Then, it was rinsed with ultrapure water for 1 minute, and dried to form a pattern on the crepe sheet. The amount of exposure necessary to completely dissolve the gap ‧ pattern of the 3.0 μm line and the gap (10 to 1) was measured. The value as the sensitivity is listed in Table 2. When the value is 1000 J/m ² or less, the sensitivity can be considered to be good.

[Evaluation of development limit]

For Examples 10 to 17, and Comparative Example 2, the compositions listed in Table 2 were applied onto a ruthenium substrate by a spin coater, and then prebaked on a hot plate at 90 ° C for 2 minutes to form a film thickness of 3.0. Μm coating film. For Example 18, coating was carried out using a slit die coater, vacuum drying was carried out at 0.5 Torr, and prebaking was carried out at 90 ° C for 2 minutes on a hot plate to form a coating film having a film thickness of 3.0 μm. The PLA-501F exposure machine (ultra-high pressure mercury lamp) manufactured by Canon was used to expose the sensitivity value measured in the above "sensitivity evaluation" via a mask having a pattern of 3.0 μm lines and spaces (10 to 1). The obtained coating film was exposed to light, and developed in a tetramethylammonium hydroxide aqueous solution having a concentration shown in Table 2 at 25 ° C for a varying development time by a liquid-holding method. Then, it was rinsed with ultrapure water for 1 minute, and dried to form a pattern on the crepe sheet. At this time, the development time necessary for the line width of the line to be 3.0 μm as the optimum development time is shown in Table 2.

Further, when the development was further continued from the optimum development time, the time until the 3.0 μm line pattern fell off was measured, and it is shown in Table 2 as the development limit. When the value is 30 seconds or more, it can be confirmed that the development limit is good.

[Evaluation of solvent resistance]

In Examples 10 to 17, and Comparative Example 2, the compositions listed in Table 2 were applied onto a ruthenium substrate by a spin coater, and then prebaked on a hot plate at 90 ° C for 2 minutes to form a coating film. For Example 18, coating was carried out using a slit die coater, vacuum drying was carried out at 0.5 Torr, and prebaking was carried out at 90 ° C for 2 minutes on a hot plate to form a coating film. The obtained coating film was exposed by a PLA-501F exposure machine (ultra-high pressure mercury lamp) manufactured by Canon at a cumulative irradiation amount of 3000 J/m ² , and the ruthenium substrate was heated in a clean oven at 220 ° C for 1 hour to obtain a thickness of 3.0 μm cured film. The film thickness (T1) of the obtained cured film was measured. Then, the ruthenium substrate on which the cured film was formed was immersed in dimethyl hydrazine having a temperature controlled at 70 ° C for 20 minutes, and then the film thickness (t1) of the cured film was measured, and the film thickness change rate by immersion was calculated {| t1-T1|/T1)×100[%]. The results are shown in Table 2. When the value is 5% or less, it is considered that the solvent resistance is good.

Further, since the film formed in the evaluation of the solvent resistance does not need to be patterned, the development step is omitted, and only the coating film forming step, the step of irradiating the radiation, and the heating step are evaluated.

[Evaluation of heat resistance]

A cured film was formed in the same manner as the evaluation of the solvent resistance described above, and the film thickness (T2) of the obtained cured film was measured. Then, the cured film substrate was placed in a clean oven and additionally baked at 240 ° C for 1 hour, and then the thickness (t2) of the cured film was measured, and the film thickness change rate by the additional baking was calculated {|t2-T2|/T2 }×100[%]. The results are shown in Table 2. When the value is 5% or less, it is considered that the heat resistance is good.

[Evaluation of adhesion of cured film]

A cured film was formed in the same manner as the evaluation of the solvent resistance described above, and an aluminum tack (manufactured by QUAD Co., Ltd.) having a circular bonding surface having a diameter of 0.27 cm coated with an epoxy resin was bonded to the cured film to make the nail and the nail The substrate was vertical and baked in a clean oven at 150 ° C for 1 hour to cure the epoxy resin. Then, the tack was pulled by a pull tester "Motorized Stand SDMS-0201-100SL (manufactured by Ikuta Seisakusho Co., Ltd.)", and the force when the cured film was separated from the substrate was measured. The force values at this time are listed in Table 2. When the value is 150 N or more, it is considered that the adhesion to the substrate is good.

[Evaluation of transparency]

In the evaluation of the solvent resistance, a cured film was formed on the glass substrate in the same manner except that the glass substrate "Corning 7059 (manufactured by Corning)" was used instead of the tantalum substrate. The light transmittance of the glass substrate having the cured film was measured in a wavelength range of 400 to 800 nm by a spectrophotometer "150-20 type double beam (manufactured by Hitachi, Ltd.)". The lowest transmittance values at this time are listed in Table 2. When the value is 90% or more, it is considered that the transparency is good.

[Evaluation of dielectric constant]

In Examples 10 to 17, and Comparative Example 2, the compositions listed in Table 2 were applied onto a polished SUS304 substrate by a spin coater, and then prebaked on a hot plate at 90 ° C for 2 minutes to form a composition. A film having a film thickness of 3.0 μm. For Example 18, coating was carried out using a slit die coater, vacuum drying was carried out at 0.5 Torr, and prebaking was carried out at 90 ° C for 2 minutes on a hot plate to form a coating film having a film thickness of 3.0 μm. The obtained coating film was exposed using a PLA-501F exposure machine (ultra-high pressure mercury lamp) manufactured by Canon at a cumulative irradiation amount of 3000 J/m ² , and the substrate was baked in a clean oven at 220 ° C for 1 hour to obtain a cured film. The cured film was formed into a Pt/Pd electrode pattern by a vapor deposition method to prepare a sample for measuring the dielectric constant. The substrate was measured for the dielectric constant of the substrate by a CV method at a frequency of 10 kHz using an HP16451B electrode manufactured by Hewlett-Packard and an HP4284A precision LCR meter. The results are shown in Table 2. When the value is 3.9 or less, the dielectric constant can be considered to be good.

Further, since the film formed in the dielectric constant evaluation does not need to be patterned, the development step is omitted, and only the coating film forming step, the step of irradiating the radiation, and the heating step are evaluated.

Examples 19 to 26 and Comparative Example 3 <Performance evaluation as microlens>

The radiation-sensitive resin composition prepared as described above was used, and various properties as microlenses were evaluated as follows. In addition, the evaluation of the solvent resistance, the evaluation of the heat resistance, and the evaluation of the transparency will be referred to the results in the performance evaluation as the interlayer insulating film described above.

[Evaluation of sensitivity]

For Examples 19 to 26 and Comparative Example 3, the compositions listed in Table 3 were applied onto a ruthenium substrate by a spin coater, and then prebaked on a hot plate at 90 ° C for 2 minutes to form a film thickness of 2.0. Μm coating film. The NSR1755i7A reduced projection projection machine (NA=0.50, λ=365 nm) manufactured by Nikon was passed through a pattern mask having a predetermined pattern, and the exposure time was changed, and the obtained coating film was exposed, and then the hydroxide shown in Table 3 was used. The tetramethylammonium aqueous solution was developed by a liquid-filling method at 25 ° C for 1 minute. Rinse with water, dry, and form a pattern on the bracts. The exposure time necessary to make the gap line width of the 0.8 μm line and the gap (1 to 1) 0.8 μm was measured. The value as the sensitivity is listed in Table 3. When the value is 2000 J/m ² or less, the sensitivity is considered to be good.

[Evaluation of development limit]

For Examples 19 to 26 and Comparative Example 3, the compositions listed in Table 3 were applied onto a ruthenium substrate by a spin coater, and then prebaked on a hot plate at 90 ° C for 2 minutes to form a film thickness of 2.0. Μm coating film. The NSR1755i7A reduced projection projection machine (NA = 0.50, λ = 365 nm) manufactured by Nikon was passed through a pattern mask having a predetermined pattern, and the obtained coating film was applied to an exposure amount equivalent to the sensitivity value measured in the above "sensitivity evaluation". The exposure was carried out, and development was carried out by a liquid-holding method at 25 ° C for 1 minute in an aqueous tetramethylammonium hydroxide solution having a concentration shown in Table 3. Rinse with water, dry, and form a pattern on the bracts. The development time necessary for making the gap line width of 0.8 μm line and gap pattern (1 to 1) 0.8 μm as the optimum development time is shown in Table 3. Further, when the development was further continued from the optimum development time, the time (development limit) at which the pattern having a width of 0.8 μm was dropped was measured, and it is shown in Table 3 as the development limit. When the value is 30 seconds or more, it can be considered that the development limit is good.

[Formation of microlenses]

For Examples 19 to 26 and Comparative Example 3, the compositions listed in Table 3 were applied onto a ruthenium substrate by a spin coater, and then pre-baked on a hot plate at 90 ° C for 2 minutes to form a film thickness of 2.0. Μm coating film. The NSR1755i7A reduced projection projection machine (NA=0.50, λ=365 nm) manufactured by Nikon was passed through a pattern mask having a 2.0 μm dot 2.0 μm gap pattern to be exposed to the sensitivity value measured in the above “sensitivity evaluation”. The obtained coating film was exposed to light, and developed in a tetramethylammonium hydroxide aqueous solution at a concentration listed in the sensitivity evaluation of Table 3 at 25 ° C for 1 minute by a liquid-filling method. Rinse with water, dry, and pattern on the bracts. Then, exposure was performed with a cumulative irradiation amount of 3000 J/m ² using a PLA-501F exposure machine (ultra-high pressure mercury lamp) manufactured by Canon. Then, after heating at 160 ° C for 10 minutes on a hot plate, it was further heated at 230 ° C for 10 minutes to cause the pattern melt to flow to form a microlens.

The dimensions (diameter) and sectional shape of the bottom of the formed microlens (the surface joined to the substrate) are shown in Table 3. When the size of the bottom of the microlens exceeds 4.0 μm and is less than 5.0 μm, it can be considered to be good. Further, if the size is 5.0 μm or more, it is in a state of being in contact with an adjacent lens, which is not preferable. Further, in the schematic view shown in Fig. 1, the cross-sectional shape is good when it is a semi-convex lens shape as shown in (a), and the case of an approximately trapezoidal shape as shown in (b) is bad.

Fig. 1 is a schematic view showing the cross-sectional shape of a microlens.

Claims (6)

A radiation sensitive resin composition characterized by comprising: [A] comprising (a1) at least one selected from the group consisting of unsaturated carboxylic acids and unsaturated carboxylic anhydrides, and (a2) having an epoxy group. a copolymer of at least one unsaturated mixture selected from the group consisting of an unsaturated compound and an unsaturated compound having an oxetane group, [B] 1,2-quinonediazide compound, and [C] The sesquioxane of the hydrolysis condensate of the decane compound represented by the formula (1): Si(R ¹ )(OR ² )(OR ³ )(OR ⁴ ) (1) wherein R ¹ represents carbon The aryl group having 6 to 15 atoms, and R ² to R ⁴ independently of each other represent a hydrogen atom, a substituted or unsubstituted alkyl group or a fluorenyl group having 1 to 4 carbon atoms. The radiation sensitive linear resin composition according to the first aspect of the invention, wherein the [C] sesquioxane is 50 to 95% by weight of the decane compound represented by the above formula (1) and 5 to 50% by weight of the following formula (2) a hydrolysis condensate of a decane compound, Si(R ⁵ )(OR ⁶ )(OR ⁷ )(OR ⁸ ) (2) wherein R ⁵ is an alkane having 1 to 15 carbon atoms Further, R ⁶ to R ⁸ are each independently a hydrogen atom, a substituted or unsubstituted alkyl group or a fluorenyl group having 1 to 4 carbon atoms. A radiation sensitive resin composition as claimed in claim 1 or 2, which is used for forming an interlayer insulating film. A method of producing an interlayer insulating film, comprising the steps of: (1) forming a coating film of a radiation-sensitive resin composition as in claim 3 of the patent application on the substrate, (2) a step of irradiating at least a part of the coating film with radiation, (3) a step of developing the coating film after the irradiation, and (4) a step of heating the coating film after the development. A radiation sensitive resin composition as claimed in claim 1 or 2 for forming a microlens. A method of producing a microlens, comprising the steps of: (1) forming a coating film of a radiation sensitive resin composition as in claim 5 of the patent application on the substrate, (2) At least a part of the coating film is irradiated with radiation, (3) a step of developing the coating film after the irradiation, and (4) a step of heating the developed coating film.