JP4650639B2 - Radiation-sensitive resin composition, interlayer insulating film and microlens, and production method thereof - Google Patents

Abstract

A radiation-sensitive resin composition that exhibits high radiation sensitivity, having such a development margin that desirable pattern configuration can be formed even when the optimum development time is exceeded in the development step, that is capable of easily forming a patterned thin film excelling in adherence and reduces the amount of sublimed matter occurring at firing, and that is appropriately usable in production of an interlayer insulation film or microlens. There is provided a radiation-sensitive resin composition comprising carboxylated epoxidized polymer (A) exhibiting a ratio of, as measured by gel permeation chromatography, weight average molecular weight (Mw) in terms of polystyrene to number average molecular weight (Mn) in terms of polystyrene, Mw/Mn, of 1.7 or below, and 1,2-quinonediazide compound (B).

Description

  The present invention relates to a radiation-sensitive resin composition, an interlayer insulating film and a microlens, and methods for producing them.

In an electronic component such as a thin film transistor (hereinafter referred to as “TFT”) type liquid crystal display element, magnetic head element, integrated circuit element, solid-state imaging element, etc., an interlayer insulation is generally used to insulate between wirings arranged in layers. A membrane is provided. As a material for forming an interlayer insulating film, a material having a small number of steps for obtaining a required pattern shape and having sufficient flatness is preferable, and thus a radiation sensitive resin composition is widely used (patents) Reference 1 and Patent Document 2).
Among the electronic components, for example, a TFT type liquid crystal display element is manufactured through a process of forming a transparent electrode film on the interlayer insulating film and further forming a liquid crystal alignment film on the interlayer insulating film. Since the film is exposed to a high temperature condition in the transparent electrode film forming process or exposed to a resist stripping solution used for forming an electrode pattern, sufficient resistance to these is required.
In recent years, TFT-type liquid crystal display elements have been in the trend of larger screens, higher brightness, higher definition, faster response, thinner thickness, etc., and the composition for forming an interlayer insulating film used therefor has high sensitivity. In addition, the interlayer insulating film to be formed is required to have higher performance than ever in terms of low dielectric constant and high transmittance.

On the other hand, a microlens having a lens diameter of about 3 to 100 μm or an optical system material for an on-chip color filter such as a facsimile, an electronic copying machine, a solid-state image sensor, or the like is defined as an optical system material. An array of microlenses is used.
To form a microlens or microlens array, a resist pattern corresponding to the lens is formed and then melt-flowed by heat treatment and used as it is as a lens, or by using the melt-flowed lens pattern as a mask and drying. A method of transferring a lens shape to a base by etching is known. For the formation of the lens pattern, a radiation sensitive resin composition is widely used (see Patent Document 3 and Patent Document 4).
By the way, the element in which the microlens or the microlens array as described above is formed is then applied with a planarizing film and an etching resist film in order to remove various insulating films on the bonding pad which is a wiring forming portion. Exposure and development are performed using a desired mask to remove the etching resist in the bonding pad portion, and then the step is performed to remove the planarizing film and various insulating films by etching to expose the bonding pad portion. For this reason, the microlens or the microlens array needs to have solvent resistance and heat resistance in the flattening film and the etching resist coating film forming process and the etching process.
The radiation-sensitive resin composition used to form such a microlens has high sensitivity, and the microlens formed therefrom has a desired radius of curvature, and has high heat resistance and high transmittance. It is required to be a rate.

In addition, the interlayer insulating film and the microlens thus obtained can penetrate between the pattern and the substrate if the development time is slightly longer than the optimum time in the development process when forming them. Therefore, it is necessary to strictly control the development time, and there is a problem in terms of product yield.
As described above, in forming the interlayer insulating film and the microlens from the radiation-sensitive resin composition, the composition is required to have high sensitivity, and the developing time in the developing process during the forming process is longer than a predetermined time. Even if it becomes excessive, the pattern does not peel off and shows good adhesion, and the interlayer insulating film formed therefrom is required to have high heat resistance, high solvent resistance, low dielectric constant, high transmittance, etc. The When forming a microlens, a good melt shape (desired radius of curvature), high heat resistance, high solvent resistance, and high transmittance are required as a microlens. A satisfactory radiation-sensitive resin composition has not been known so far.
There is a concern that the above-described sublimates generated during firing to form interlayer insulating films and microlenses contaminate process lines and devices, and a radiation-sensitive resin composition in which generated sublimates are reduced is desired. It was.

JP 2001-354822 A JP 2001-343743 A JP-A-6-18702 JP-A-6-136239

  The present invention has been made based on the above situation. Therefore, an object of the present invention is to provide a pattern shape having high radiation sensitivity, having a development margin capable of forming a good pattern shape even in the development process exceeding the optimum development time, and having excellent adhesion. An object of the present invention is to provide a radiation-sensitive composition in which a thin film can be easily formed and sublimates generated during firing are reduced.

  Another object of the present invention is to form an interlayer insulating film having high heat resistance, high solvent resistance, high transmittance and low dielectric constant when used for forming an interlayer insulating film, and for forming a microlens. When used, the object is to provide a radiation-sensitive resin composition in which a microlens having a high transmittance and a good melt shape is formed, and sublimates generated during firing are reduced.

  Still another object of the present invention is to provide a method for forming an interlayer insulating film and a microlens using the radiation sensitive resin composition.

  Still another object of the present invention is to provide an interlayer insulating film and a microlens formed by the method of the present invention.

  Still other objects and advantages of the present invention will become apparent from the following description.

According to the present invention, the above objects and advantages of the present invention are as follows.
(A) A copolymer obtained by living radical polymerization using a thiocarbonylthio compound as a control agent, having a carboxyl group and an epoxy group, and having a weight average molecular weight in terms of polystyrene (Mw) measured by gel permeation chromatography ) and the ratio of polystyrene-reduced number average molecular weight (Mn) (Mw / Mn) is co-polymer with 1.7 or less, and (B) a radiation-sensitive resin which is characterized by containing a 1,2-quinonediazide compound Achieved by the composition.

The above objects and advantages of the present invention are secondly,
The following steps are carried out in the order described below, and this is achieved by a method for forming an interlayer insulating film or microlens.
(1) The process of forming the coating film of said radiation sensitive resin composition on a board | substrate,
(2) A step of irradiating at least a part of the coating film with radiation,
(3) Development step, and (4) Heating step.

Further, the above object and advantage of the present invention are as follows.
This is achieved by the interlayer insulating film and the microlens formed by the above method.

It is a schematic diagram showing the cross-sectional shape of a micro lens.

  Hereinafter, the radiation sensitive resin composition of this invention is explained in full detail.

Copolymer (A)
The copolymer (A) used in the present invention is preferably (a1) an unsaturated carboxylic acid and / or an unsaturated carboxylic acid anhydride (hereinafter sometimes referred to as “compound (a1)”),
(A2) an epoxy group-containing unsaturated compound (hereinafter sometimes referred to as “compound (a2)”),
And (a3) a polymerizable mixture containing an unsaturated compound other than the components (a1) and (a2) (hereinafter sometimes referred to as “compound (a3)”) is advantageously obtained by living radical polymerization.
For example, the copolymer (A) is produced by subjecting a polymerizable mixture containing the compound (a1), the compound (a2) and the compound (a3) to living radical polymerization in a solvent in the presence of a polymerization initiator. Can do.
The carboxyl group and epoxy group of the copolymer (A) thus obtained are derived from the compound (a1) and the compound (a2), respectively.
Various initiator systems for living radical polymerization have been proposed. For example, the TEMPO system found by Georges et al., The initiator system composed of a combination of copper bromide and bromine-containing ester compounds proposed by Matyjazewski et al., Carbon tetrachloride and ruthenium proposed by Higashira et al. II) Initiator systems composed of combinations of complexes, combinations of thiocarbonylthio compounds and radical initiators described in JP-T 2000-515181, JP-A 2002-500261, and JP-A 2004-518773 Has been proposed .

Polymer (A) Li Bing polymerization initiator system for obtaining the present invention, a but growing terminal by monomer species used deactivation city system is appropriately selected, considered from the polymerization efficiency and the like, Ji o A combination of a carbonylthio compound and a radical initiator. Here, examples of the thiocarbonylthio compound include dithioesters, dithiocarbonates, trithiocarbonates, xanthates and the like.
Specific examples thereof include compounds represented by the following formula.

  Among these, cumyl dithiobenzoate, S-cyanomethyl-S-dodecyl trithiocarbonate, pyrazole-1-dithiocarboxylic acid phenyl-methyl ester, dithioester used in Synthesis Example 5 below and used in Synthesis Example 6 below Xanthate can be mentioned.

Further, as the radical initiator, those generally known as radical polymerization initiators can be used. For example, 2,2′-azobisisobutyronitrile, 2,2′-azobis- (2,4 -Dimethylvaleronitrile), 2,2'-azobis- (4-methoxy-2,4-dimethylvaleronitrile) and other azo compounds; benzoyl peroxide, lauroyl peroxide, t-butylperoxypivalate, 1,1'-bis Examples thereof include organic peroxides such as-(t-butylperoxy) cyclohexane; hydrogen peroxide; redox initiators composed of these peroxides and a reducing agent.
These polymerization initiators can be used alone or in admixture of two or more.
The amount of the thiocarbonylthio compound used is preferably 1 to 10,000 parts by weight, more preferably 10 to 1,000 parts by weight per 100 parts by weight of the polymerization initiator. The amount of the radical polymerization initiator used is preferably 0.01 to 100 parts by weight, more preferably 0.1 to 100 parts by weight per 100 parts by weight of the monomer mixture containing the epoxy group-containing polymerizable unsaturated compound. 10 parts by weight. Although there is no restriction | limiting in particular in the polymerization temperature in the case of the said living radical polymerization, Preferably it is 0 to 100 degreeC, More preferably, it is 10 to 85 degreeC.
Depending on the initiator system, polymerization may be carried out by using an ester compound (a1 ′) in which the carboxyl group of the compound (a1) is appropriately protected with a protecting group so that the polymerization initiator is not deactivated, and then deprotecting. A coalescence (A) can also be obtained.

The copolymer (A) used in the present invention is a total of polymerization units or repeating units derived from the compounds (a1), (a2) and (a3). Is preferably 5 to 40% by weight, particularly preferably 10 to 30% by weight. When a copolymer having a polymerization unit of less than 5% by weight is used, it is difficult to dissolve in an alkaline aqueous solution during the development process, while a copolymer exceeding 40% by weight tends to be too soluble in an alkaline aqueous solution. .
The compound (a1) is an unsaturated carboxylic acid and / or unsaturated carboxylic acid anhydride having radical polymerizability, such as monocarboxylic acid, dicarboxylic acid, dicarboxylic acid anhydride, polyvalent carboxylic acid mono [(meth)]. Acryloyloxyalkyl] ester, mono (meth) acrylate of a polymer having a carboxyl group and a hydroxyl group at both ends, a polycyclic compound having a carboxyl group, and anhydrides thereof.

Specific examples thereof include monocarboxylic acids such as acrylic acid, methacrylic acid, and crotonic acid;
Examples of dicarboxylic acids include maleic acid, fumaric acid, citraconic acid, mesaconic acid, itaconic acid and the like;
Examples of dicarboxylic acid anhydrides include, for example, acid anhydrides of the above compounds exemplified as the dicarboxylic acid;
Examples of mono [(meth) acryloyloxyalkyl] esters of polyvalent carboxylic acids such as succinic acid mono [2- (meth) acryloyloxyethyl] and phthalic acid mono [2- (meth) acryloyloxyethyl];
Examples of mono (meth) acrylate of a polymer having a carboxyl group and a hydroxyl group at each of both ends, such as ω-carboxypolycaprolactone mono (meth) acrylate;
Examples of the polycyclic compound having a carboxyl group and anhydrides thereof include 5-carboxybicyclo [2.2.1] hept-2-ene and 5,6-dicarboxybicyclo [2.2.1] hept-2-ene. 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] And hept-2-ene anhydride.

Of these, monocarboxylic acid and dicarboxylic acid anhydrides are preferably used, and acrylic acid, methacrylic acid, and maleic anhydride are particularly preferably used from the viewpoints of copolymerization reactivity, solubility in alkaline aqueous solutions, and availability. . These may be used alone or in combination.
The protecting group for protecting the carboxyl group of the compound (a1) is not particularly limited, and a known protecting group for the carboxyl group can be used. Examples thereof include a trialkylsilyl group, a 1-alkoxyalkyl group, and a cyclic 1-alkoxyalkyl group. More specifically, for example, trimethylsilyl, dimethylbutylsilyl, 1-ethoxyethyl, 1-propoxyethyl, tetrahydrofuranyl, tetrahydropyranyl, triphenylmethyl and the like can be mentioned.
The copolymer (A) used in the present invention is preferably a polymer unit derived from the compound (a2) based on the total of polymer units derived from the compounds (a1), (a2) and (a3). 10 to 70% by weight, particularly preferably 20 to 60% by weight. If this polymerized unit is less than 10% by weight, the heat resistance and surface hardness of the resulting interlayer insulating film and microlens tend to be reduced. On the other hand, if the amount of this polymerized unit exceeds 70% by weight, the radiation sensitive resin The storage stability of the composition tends to decrease.

  The compound (a2) is an epoxy group-containing unsaturated compound having radical polymerizability. Examples include glycidyl acrylate, glycidyl methacrylate, glycidyl α-ethyl acrylate, glycidyl α-n-propyl acrylate, glycidyl α-n-butyl acrylate, 3,4-epoxybutyl acrylate, methacrylic acid- 3,4-epoxybutyl, acrylic acid-6,7-epoxyheptyl, methacrylic acid-6,7-epoxyheptyl, α-ethylacrylic acid-6,7-epoxyheptyl, o-vinylbenzylglycidyl ether, m-vinyl Examples thereof include benzyl glycidyl ether and p-vinylbenzyl glycidyl ether. Among these, glycidyl methacrylate, methacrylic acid-6,7-epoxyheptyl, o-vinylbenzyl glycidyl ether, m-vinylbenzyl glycidyl ether, p-vinylbenzyl glycidyl ether, 3,4-epoxycyclohexyl methacrylate, etc. It is preferably used from the viewpoint of increasing the copolymerization reactivity and the heat resistance and surface hardness of the obtained interlayer insulating film or microlens. These may be used alone or in combination.

The copolymer (A) used in the present invention is preferably a polymer unit derived from the compound (a3) based on the total of the polymer units derived from the compounds (a1), (a2) and (a3). 5 to 70% by weight, particularly preferably 5 to 50% by weight. When this polymerized unit is less than 5% by weight, the storage stability of the radiation-sensitive resin composition tends to be reduced. On the other hand, when it exceeds 70% by weight, in the development step in the formation of an interlayer insulating film or microlens, It may be difficult to dissolve in an alkaline aqueous solution.
The compound (a3) is not particularly limited as long as it is an unsaturated compound having radical polymerizability. Examples thereof include methacrylic acid alkyl esters, acrylic acid alkyl esters, methacrylic acid cyclic alkyl esters, and methacrylic acid esters having a hydroxyl group. Acrylic acid cyclic alkyl ester, methacrylic acid aryl ester, acrylic acid aryl ester, unsaturated dicarboxylic acid diester, bicyclounsaturated compound, maleimide compound, unsaturated aromatic compound, and conjugated diene.

Specific examples thereof include methacrylic acid alkyl esters such as methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, sec-butyl methacrylate, t-butyl methacrylate, 2-ethylhexyl methacrylate, isodecyl methacrylate, n-lauryl methacrylate, Decyl methacrylate, n-stearyl methacrylate, etc .;
Examples of acrylic acid alkyl esters such as methyl acrylate and isopropyl acrylate;
Examples of cyclic alkyl esters of methacrylic acid include cyclohexyl methacrylate, 2-methylcyclohexyl methacrylate, tricyclo [5.2.1.0 ^2,6 ] decan-8-yl methacrylate, tricyclo [5.2.1.0 ^2,6 ]. Decane-8-yloxyethyl methacrylate, isobornyl methacrylate, etc .;
Examples of the methacrylic acid ester having a hydroxyl group include hydroxymethyl methacrylate, 2-hydroxyethyl methacrylate, 3-hydroxypropyl methacrylate, 4-hydroxybutyl methacrylate, diethylene glycol monomethacrylate, 2,3-dihydroxypropyl methacrylate, and 2-methacryloxyethylglycol. Side, 4-hydroxyphenyl methacrylate, etc .;
Examples of acrylic acid cyclic alkyl esters include cyclohexyl acrylate, 2-methylcyclohexyl acrylate, tricyclo [5.2.1.0 ^2,6 ] decan-8-yl acrylate, tricyclo [5.2.1.0 ^2,6 ]. Decane-8-yloxyethyl acrylate, isobornyl acrylate and the like;
Methacrylic acid aryl esters such as phenyl methacrylate and benzyl methacrylate;
Examples of acrylic acid aryl esters such as phenyl acrylate and benzyl acrylate;

Unsaturated dicarboxylic acid diesters such as diethyl maleate, diethyl fumarate, diethyl itaconate and the like;
Examples of the bicyclo unsaturated compound include bicyclo [2.2.1] hept-2-ene, 5-methylbicyclo [2.2.1] hept-2-ene, and 5-ethylbicyclo [2.2.1] hept. 2-ene, 5-methoxybicyclo [2.2.1] hept-2-ene, 5-ethoxybicyclo [2.2.1] hept-2-ene, 5,6-dimethoxybicyclo [2.2. 1] hept-2-ene, 5,6-diethoxybicyclo [2.2.1] hept-2-ene, 5-t-butoxycarbonylbicyclo [2.2.1] hept-2-ene, 5- Cyclohexyloxycarbonylbicyclo [2.2.1] hept-2-ene, 5-phenoxycarbonylbicyclo [2.2.1] hept-2-ene, 5,6-di (t-butoxycarbonyl) bicyclo [2. 2.1] Hept-2 Ene, 5,6-di (cyclohexyloxycarbonyl) bicyclo [2.2.1] hept-2-ene, 5- (2′-hydroxyethyl) bicyclo [2.2.1] hept-2-ene, 5 , 6-Dihydroxybicyclo [2.2.1] hept-2-ene, 5,6-di (hydroxymethyl) bicyclo [2.2.1] hept-2-ene, 5,6-di (2′- Hydroxyethyl) bicyclo [2.2.1] hept-2-ene, 5-hydroxy-5-methylbicyclo [2.2.1] hept-2-ene, 5-hydroxy-5-ethylbicyclo [2.2 .1] hept-2-ene, 5-hydroxymethyl-5-methylbicyclo [2.2.1] hept-2-ene and the like;
Examples of maleimide compounds include phenylmaleimide, cyclohexylmaleimide, benzylmaleimide, N-succinimidyl-3-maleimidobenzoate, N-succinimidyl-4-maleimidobutyrate, N-succinimidyl-6-maleimidocaproate, N-succinimidyl-3- Maleimide propionate, N- (9-acridinyl) maleimide and the like;
Examples of unsaturated aromatic compounds include styrene, α-methylstyrene, m-methylstyrene, p-methylstyrene, vinyltoluene, p-methoxystyrene, and the like;
Examples of conjugated dienes include 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, and the like;
Examples of other unsaturated compounds include acrylonitrile, methacrylonitrile, vinyl chloride, vinylidene chloride, acrylamide, methacrylamide, and vinyl acetate.

Of these, methacrylic acid alkyl esters, methacrylic acid cyclic alkyl esters, bicyclounsaturated compounds, unsaturated aromatic compounds, and conjugated dienes are preferably used, and styrene, t-butyl methacrylate, tricyclo [5.2.1. 0 ^2,6 ] decan-8-yl methacrylate, p-methoxystyrene, 2-methylcyclohexyl acrylate, 1,3-butadiene, and bicyclo [2.2.1] hept-2-ene are copolymerizable and alkaline aqueous solution. It is particularly preferred from the viewpoint of solubility in These may be used alone or in combination.

Preferable specific examples of the copolymer (A) used in the present invention include, for example, methacrylic acid / styrene / tricyclo [5.2.1.0 ^2,6 ] decan-8-yl methacrylate / glycidyl methacrylate / tetrahydro Furfuryl methacrylate copolymer, methacrylic acid / styrene / tricyclo [5.2.1.0 ^2,6 ] decan-8-yl methacrylate / glycidyl methacrylate / p-vinylbenzyl glycidyl ether / tetrahydrofurfuryl methacrylate copolymer , Methacrylic acid / styrene / tricyclo [5.2.1.0 ^2,6 ] decan-8-yl methacrylate / glycidyl methacrylate / polyethylene glycol monomethacrylate copolymer, methacrylic acid / styrene / tricyclo [5.2.1 .0 ^2,6] decan-8-b Methacrylate / glycidyl methacrylate / polypropylene glycol monomethacrylate copolymers.

The copolymer (A) used in the present invention is a ratio of polystyrene-equivalent weight average molecular weight (hereinafter referred to as “Mw”) and polystyrene-equivalent number average molecular weight (hereinafter referred to as “Mn”) measured by gel permeation chromatography (hereinafter referred to as “Mn”). Mw / Mn) is 1.7 or less, preferably 1.5 or less. When Mw / Mn exceeds 1.7, the pattern shape of the obtained interlayer insulating film or microlens may be inferior. Further, Mw is preferably 2 × 10 ³ to 1 × 10 ⁵ , more preferably 5 × 10 ^{3 to} 5 × 10 ⁴ . If the Mw is less than 2 × 10 ³ , the development margin may not be sufficient, the remaining film ratio of the resulting film may decrease, the pattern shape of the resulting interlayer insulating film or microlens, heat resistance, etc. May be inferior. On the other hand, if Mw exceeds 1 × 10 ⁵ , the sensitivity may decrease or the pattern shape may be inferior. Moreover, Mn is preferably 1.2 × 10 ³ to 1 × 10 ⁵ , and more preferably 2.9 × 10 ^{3 to} 5 × 10 ⁴ . The radiation-sensitive resin composition containing the copolymer [A] can easily form a predetermined pattern shape without causing a development residue during development.

  Further, the amount of residual monomer measured by gel permeation chromatography of the copolymer (A) used in the present invention is preferably less than 5.0%, more preferably less than 3.0%, particularly preferably 2.0. %. By using such a copolymer having a residual monomer content, a protective film in which sublimates during firing are reduced can be obtained.

In this invention, a copolymer (A) can be used individually or in mixture of 2 or more types.
Examples of the solvent used for the production of the copolymer (A) include alcohol, ether, glycol ether, ethylene glycol alkyl ether acetate, diethylene glycol, propylene glycol monoalkyl ether, propylene glycol alkyl ether acetate, propylene glycol alkyl ether propio. Nates, aromatic hydrocarbons, ketones, esters and the like.

Specific examples thereof include alcohols such as methanol, ethanol, benzyl alcohol, 2-phenylethyl alcohol, and 3-phenyl-1-propanol;
Ethers such as tetrahydrofuran;
Examples of glycol ethers include ethylene glycol monomethyl ether and ethylene glycol monoethyl ether;
Examples of ethylene glycol alkyl ether acetate include methyl cellosolve acetate, ethyl cellosolve acetate, ethylene glycol monobutyl ether acetate, and ethylene glycol monoethyl ether acetate;
Examples of diethylene glycol include diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, and diethylene glycol ethyl methyl ether.
Examples of propylene glycol monoalkyl ethers include propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether;
Examples of propylene glycol alkyl ether acetates include propylene glycol methyl ether acetate, propylene glycol ethyl ether acetate, propylene glycol propyl ether acetate, propylene glycol butyl ether acetate;
As propylene glycol alkyl ether propionate, for example, propylene glycol methyl ether propionate, propylene glycol ethyl ether propionate, propylene glycol propyl ether propionate, propylene glycol butyl ether propionate, etc .;
Aromatic hydrocarbons such as toluene, xylene, etc .;
Examples of ketones include methyl ethyl ketone, cyclohexanone, 4-hydroxy-4-methyl-2-pentanone, etc .;

Examples of esters include methyl acetate, ethyl acetate, propyl acetate, butyl acetate, ethyl 2-hydroxypropionate, methyl 2-hydroxy-2-methylpropionate, ethyl 2-hydroxy-2-methylpropionate, methyl hydroxyacetate, hydroxy Ethyl acetate, hydroxybutyl acetate, methyl lactate, ethyl lactate, propyl lactate, butyl lactate, methyl 3-hydroxypropionate, ethyl 3-hydroxypropionate, propyl 3-hydroxypropionate, butyl 3-hydroxypropionate, 2-hydroxy -3-methylbutanoate, methyl methoxyacetate, ethyl methoxyacetate, propyl methoxyacetate, butyl methoxyacetate, methyl ethoxy acetate, ethyl ethoxy acetate, propyl ethoxy acetate, butyl ethoxy acetate, propoxy Methyl acetate, ethyl propoxyacetate, propyl propoxyacetate, butyl propoxyacetate, methyl butoxyacetate, ethyl butoxyacetate, propyl butoxyacetate, butylbutoxyacetate, methyl 2-methoxypropionate, ethyl 2-methoxypropionate, 2-methoxypropionic acid Propyl, butyl 2-methoxypropionate, methyl 2-ethoxypropionate, ethyl 2-ethoxypropionate, propyl 2-ethoxypropionate, butyl 2-ethoxypropionate, methyl 2-butoxypropionate, ethyl 2-butoxypropionate Propyl 2-butoxypropionate, butyl 2-butoxypropionate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, propyl 3-methoxypropionate, 3-methoxypropyl Butyl pionate, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, propyl 3-ethoxypropionate, butyl 3-ethoxypropionate, methyl 3-propoxypropionate, ethyl 3-propoxypropionate, 3-propoxypropionate Examples thereof include esters such as propyl acid, butyl 3-propoxypropionate, methyl 3-butoxypropionate, ethyl 3-butoxypropionate, propyl 3-butoxypropionate, and butyl 3-butoxypropionate.
Of these, ethylene glycol alkyl ether acetate, diethylene glycol, propylene glycol monoalkyl ether, and propylene glycol alkyl ether acetate are preferable. Among them, diethylene glycol dimethyl ether, diethylene glycol ethyl methyl ether, propylene glycol methyl ether, and propylene glycol methyl ether acetate are particularly preferable. .

Component (B) The component (B) used in the present invention is a 1,2-quinonediazide compound that generates a carboxylic acid upon irradiation with radiation, and is a phenolic compound or an alcoholic compound (hereinafter referred to as “mother nucleus”). And a condensate of 1,2-naphthoquinonediazide sulfonic acid halide can be used.
Examples of the mother nucleus include trihydroxybenzophenone, tetrahydroxybenzophenone, pentahydroxybenzophenone, hexahydroxybenzophenone, (polyhydroxyphenyl) alkane, and other mother nuclei.

Specific examples thereof include trihydroxybenzophenone such as 2,3,4-trihydroxybenzophenone and 2,4,6-trihydroxybenzophenone;
Examples of tetrahydroxybenzophenone include 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 .;
Examples of pentahydroxybenzophenone include 2,3,4,2 ′, 6′-pentahydroxybenzophenone and the like;
Examples of hexahydroxybenzophenone include 2,4,6,3 ′, 4 ′, 5′-hexahydroxybenzophenone, 3,4,5,3 ′, 4 ′, 5′-hexahydroxybenzophenone and the like;
Examples of (polyhydroxyphenyl) alkanes include bis (2,4-dihydroxyphenyl) methane, bis (p-hydroxyphenyl) methane, tri (p-hydroxyphenyl) methane, and 1,1,1-tri (p-hydroxyphenyl). ) Ethane, bis (2,3,4-trihydroxyphenyl) methane, 2,2-bis (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-hydroxyphenylmethane, 3,3,3 ′, 3′-tetramethyl-1,1′-spirobiindene-5 6,7,5 ′, 6 ′, 7′-hexanol, 2,2,4-trimethyl-7,2 ′, 4′-trihydroxyflavan and the like;
As other mother nucleus, for example, 2-methyl-2- (2,4-dihydroxyphenyl) -4- (4-hydroxyphenyl) -7-hydroxychroman, 2- [bis {(5-isopropyl-4-hydroxy- 2-methyl) phenyl} methyl], 1- [1- (3- {1- (4-hydroxyphenyl) -1-methylethyl} -4,6-dihydroxyphenyl) -1-methylethyl] -3- ( 1- (3- {1- (4-hydroxyphenyl) -1-methylethyl} -4,6-dihydroxyphenyl) -1-methylethyl) benzene, 4,6-bis {1- (4-hydroxyphenyl) -1-methylethyl} -1,3-dihydroxybenzene.
Further, 1,2-naphthoquinone diazide sulfonic acid amides in which the ester bond of the mother nucleus exemplified above is changed to an amide bond, for example, 2,3,4-trihydroxybenzophenone-1,2-naphthoquinone diazide-4-sulfonic acid amide Etc. are also preferably used.

Among these mother nuclei, 2,3,4,4′-tetrahydroxybenzophenone, 4,4 ′-[1- [4- [1- [4-hydroxyphenyl] -1-methylethyl] phenyl] ethylidene] Bisphenol is preferred.
The 1,2-naphthoquinone diazide sulfonic acid halide is preferably 1,2-naphthoquinone diazide sulfonic acid chloride. Specific examples thereof include 1,2-naphthoquinone diazide-4-sulfonic acid chloride and 1,2-naphthoquinone diazide. -5-sulfonic acid chloride can be mentioned, and among these, 1,2-naphthoquinonediazide-5-sulfonic acid chloride is preferably used.
In the condensation reaction, 1,2-naphthoquinonediazide sulfonic acid halide corresponding to 30 to 85 mol%, more preferably 50 to 70 mol%, with respect to 1 equivalent of OH group in the phenolic compound or alcoholic compound. Can be used.
The condensation reaction can be carried out by a known method.
These components (B) can be used alone or in combination of two or more.
(B) The usage-amount of a component becomes like this. Preferably it is 5-100 weight part with respect to 100 weight part of copolymers (A), More preferably, it is 10-50 weight part. When this ratio is less than 5 parts by weight, the difference in solubility between the irradiated portion and the unirradiated portion in the alkaline aqueous solution that is the developer is small, and patterning may be difficult. Alternatively, the heat resistance and solvent resistance of the microlens may be insufficient. On the other hand, when this ratio exceeds 100 parts by weight, the solubility in the alkaline aqueous solution may be insufficient in the radiation irradiated portion, and development may be difficult.

Other Components The radiation-sensitive resin composition of the present invention contains (C) a heat-sensitive acid generating compound, (D) as necessary, in addition to the components (A) and (B) described above. It contains at least one polymerizable compound having an ethylenically unsaturated double bond, (E) an epoxy resin other than the copolymer (A), (F) a surfactant, or (G) an adhesion assistant. Can do.
The (C) thermosensitive acid-generating compound can be used to improve heat resistance and hardness. Specific examples thereof include onium salts such as sulfonium salts, benzothiazonium salts, ammonium salts, and phosphonium salts.
Specific examples of the sulfonium salt include alkylsulfonium salts, benzylsulfonium salts, dibenzylsulfonium salts, substituted benzylsulfonium salts and the like.

Specific examples thereof include, for example, 4-acetophenyldimethylsulfonium hexafluoroantimonate, 4-acetoxyphenyldimethylsulfonium hexafluoroarsenate, dimethyl-4- (benzyloxycarbonyloxy) phenylsulfonium hexafluoroantimony as alkylsulfonium salts. Dimethyl-4- (benzoyloxy) phenylsulfonium hexafluoroantimonate, dimethyl-4- (benzoyloxy) phenylsulfonium hexafluoroarsenate, dimethyl-3-chloro-4-acetoxyphenylsulfonium hexafluoroantimonate, etc .;
Benzyl-4-hydroxyphenylmethylsulfonium hexafluoroantimonate, benzyl-4-hydroxyphenylmethylsulfonium hexafluorophosphate, 4-acetoxyphenylbenzylmethylsulfonium hexafluoroantimonate, benzyl-4-methoxyphenylmethylsulfonium hexanium as benzylsulfonium salts Fluoroantimonate, benzyl-2-methyl-4-hydroxyphenylmethylsulfonium hexafluoroantimonate, benzyl-3-chloro-4-hydroxyphenylmethylsulfonium hexafluoroarsenate, 4-methoxybenzyl-4-hydroxyphenylmethylsulfonium hexa Fluorophosphate, etc .;
Dibenzyl-4-hydroxyphenylsulfonium hexafluoroantimonate, dibenzyl-4-hydroxyphenylsulfonium hexafluoroantimonate, 4-acetoxyphenyldibenzylsulfonium hexafluoroantimonate, dibenzyl-4-methoxyphenylsulfonium hexafluoroantimonate as dibenzylsulfonium salts Dibenzyl-3-chloro-4-hydroxyphenylsulfonium hexafluoroarsenate, dibenzyl-3-methyl-4-hydroxy-5-tert-butylphenylsulfonium hexafluoroantimonate, benzyl-4-methoxybenzyl-4-hydroxy Phenylsulfonium hexafluorophosphate, etc .;
P-Chlorobenzyl-4-hydroxyphenylmethylsulfonium hexafluoroantimonate, p-nitrobenzyl-4-hydroxyphenylmethylsulfonium hexafluoroantimonate, p-chlorobenzyl-4-hydroxyphenylmethylsulfonium hexafluoro as substituted benzylsulfonium salts Phosphate, p-nitrobenzyl-3-methyl-4-hydroxyphenylmethylsulfonium hexafluoroantimonate, 3,5-dichlorobenzyl-4-hydroxyphenylmethylsulfonium hexafluoroantimonate, o-chlorobenzyl-3-chloro-4 -Hydroxyphenylmethylsulfonium hexafluoroantimonate etc. can be mentioned, respectively.

Specific examples of the benzothiazonium salt include 3-benzylbenzothiazonium hexafluoroantimonate, 3-benzylbenzothiazonium hexafluorophosphate, 3-benzylbenzothiazonium tetrafluoroborate, 3- (p- Benzylbenzothiazonium such as methoxybenzyl) benzothiazonium hexafluoroantimonate, 3-benzyl-2-methylthiobenzothiazonium hexafluoroantimonate, 3-benzyl-5-chlorobenzothiazonium hexafluoroantimonate Salt.
Of these, sulfonium salts and benzothiazonium salts are preferably used, particularly 4-acetoxyphenyldimethylsulfonium hexafluoroarsenate, benzyl-4-hydroxyphenylmethylsulfonium hexafluoroantimonate, 4-acetoxyphenylbenzylmethylsulfonium hexanium. Fluoroantimonate, dibenzyl-4-hydroxyphenylsulfonium hexafluoroantimonate, 4-acetoxyphenylbenzylsulfonium hexafluoroantimonate, and 3-benzylbenzothiazonium hexafluoroantimonate are preferably used.
Examples of these commercially available products include Sun-Aid SI-L85, SI-L110, SI-L145, SI-L150, SI-L160 (manufactured by Sanshin Chemical Industry Co., Ltd.).

The proportion of component (C) used is preferably 20 parts by weight or less, more preferably 5 parts by weight or less with respect to 100 parts by weight of copolymer (A). When the amount used exceeds 20 parts by weight, precipitates may be deposited in the coating film forming step, which may hinder the coating film formation.
Examples of the polymerizable compound having at least one ethylenically unsaturated double bond as the component (D) (hereinafter sometimes referred to as “component D”) include monofunctional (meth) acrylate, bifunctional ( Preferable examples include (meth) acrylate or tri- or higher functional (meth) acrylate.

Examples of the monofunctional (meth) acrylate include 2-hydroxyethyl (meth) acrylate, carbitol (meth) acrylate, isobornyl (meth) acrylate, 3-methoxybutyl (meth) acrylate, and 2- (meth) acryloyloxyethyl. And 2-hydroxypropyl phthalate. As these commercial products, for example, Aronix M-101, M-111, M-114 (above, manufactured by Toagosei Co., Ltd.), KAYARAD TC-110S, TC-120S (above, Nippon Kayaku Co., Ltd.) ) Co., Ltd.), Biscoat 158, 2311 (above, manufactured by Osaka Organic Chemical Industry Co., Ltd.).
Examples of the bifunctional (meth) acrylate include ethylene glycol (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, polypropylene glycol di (meth) acrylate, Examples include tetraethylene glycol di (meth) acrylate, bisphenoxyethanol full orange acrylate, and bisphenoxyethanol full orange acrylate. As these commercial products, for example, Aronix M-210, M-240, M-6200 (above, manufactured by Toagosei Co., Ltd.), KAYARAD HDDA, HX-220, R-604 (above, Nippon Kayaku) Medicine Co., Ltd.), Biscoat 260, 312 and 335HP (Osaka Organic Chemical Co., Ltd.).

Examples of the trifunctional or higher functional (meth) acrylate include trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, tri ((meth) acryloyloxyethyl) phosphate, and pentaerythritol tetra (meth) acrylate. , Dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, and the like. Examples of commercially available products include Aronix M-309, M-400, M-405, M-450, M-7100, M-8030, and M-8060 (above, manufactured by Toagosei Co., Ltd.). ), KAYARAD TMPTA, DPHA, DPCA-20, DPCA-30, DPCA-60, DPCA-120 (above, Nippon Kayaku Co., Ltd.), Biscote 295, 300, 360, GPT 3PA, 400 (above, manufactured by Osaka Organic Chemical Industry Co., Ltd.).
Of these, a tri- or higher functional (meth) acrylate is preferably used, and among them, trimethylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, and dipentaerythritol hexa (meth) acrylate are particularly preferable.

These monofunctional, bifunctional, or trifunctional or higher (meth) acrylates are used alone or in combination. (D) The usage-amount of a component becomes like this. Preferably it is 50 weight part or less with respect to 100 weight part of copolymers (A), More preferably, it is 30 weight part or less.
By including the component (D) at such a ratio, the heat resistance, surface hardness, etc. of the interlayer insulating film or microlens obtained from the radiation-sensitive resin composition of the present invention can be improved. If the amount used exceeds 50 parts by weight, film roughening 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) as the component (E) (hereinafter sometimes referred to as “E component”) is not limited as long as the compatibility is not affected, but preferably (Co) polymerization of bisphenol A type epoxy resin, phenol novolac type epoxy resin, cresol novolak type epoxy resin, cycloaliphatic epoxy resin, glycidyl ester type epoxy resin, glycidylamine type epoxy resin, heterocyclic epoxy resin, glycidyl methacrylate And the like. Of these, bisphenol A type epoxy resins, cresol novolac type epoxy resins, glycidyl ester type epoxy resins and the like are more preferable.
(E) The usage-amount of a component becomes like this. Preferably it is 30 weight part or less with respect to 100 weight part of copolymers (A). By containing (E) component in such a ratio, the heat resistance, surface hardness, etc. of the protective film or insulating film obtained from the radiation-sensitive resin composition of the present invention can be further improved. When this ratio exceeds 30 parts by weight, the film thickness uniformity of the coating film may be insufficient when a coating film of the radiation sensitive resin composition is formed on the substrate.

The copolymer (A) can also be referred to as an “epoxy resin”, but the copolymer (A) is different from the component (E) in that it has alkali solubility.
In the radiation sensitive resin composition of the present invention, a surfactant which is the component (F) can be used to further improve the coating property. As the surfactant (F) that can be used here, for example, a fluorine-based surfactant, a silicone-based surfactant, and a nonionic surfactant can be suitably used.

  Specific examples of the fluorosurfactant include 1,1,2,2-tetrafluorooctyl (1,1,2,2-tetrafluoropropyl) ether, 1,1,2,2-tetrafluorooctylhexyl ether. , Octaethylene glycol di (1,1,2,2-tetrafluorobutyl) ether, hexaethylene glycol (1,1,2,2,3,3-hexafluoropentyl) ether, octapropylene glycol di (1,1 , 2,2-tetrafluorobutyl) ether, hexapropylene glycol di (1,1,2,2,3,3-hexafluoropentyl) ether, sodium perfluorododecyl sulfonate, 1,1,2,2,8 , 8,9,9,10,10-decafluorododecane, 1,1,2,2,3,3-hexafluorodecane, etc. Sodium Zensuruhon acid; fluoroalkyl polyoxyethylene ethers fluoroalkyl ammonium iodide, fluoroalkyl polyoxyethylene ethers, perfluoroalkyl polyoxyethylene ethanol; can be exemplified fluorine-based alkyl esters; perfluoroalkyl alkoxylates. Examples of these commercially available products include BM-1000, BM-1100 (manufactured by BM Chemie), MegaFuck F142D, F172, F173, F183, F178, F191, F191 (and above, Dainippon Ink). Chemical Industries, Ltd.), Fluorad FC-170C, FC-171, FC-430, FC-431 (above, manufactured by Sumitomo 3M), Surflon S-112, S-113, S-131, S-141, S-145, S-382, SC-101, SC-102, SC-103, SC-104, SC-105, SC-106 (manufactured by Asahi Glass Co., Ltd.) ), F-top EF301, 303, and 352 (manufactured by Shin-Akita Kasei Co., Ltd.).

  Examples of the silicone surfactant include DC3PA, DC7PA, FS-1265, SF-8428, SH11PA, SH21PA, SH28PA, SH29PA, SH30PA, SH-190, SH-193, SZ-6032 (above, Toray Dow Corning)・ Silicon Co., Ltd.), TSF-4440, TSF-4300, TSF-4445, TSF-4446, TSF-4460, TSF-4442 (above, GE Toshiba Silicone Co., Ltd.) are commercially available. You can list what you have.

Examples of the nonionic surfactant include polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, and polyoxyethylene oleyl ether; polyoxyethylene octyl phenyl ether, polyoxyethylene nonyl phenyl ether, and the like. Polyoxyethylene aryl ethers; polyoxyethylene dialkyl esters such as polyoxyethylene dilaurate and polyoxyethylene distearate; (meth) acrylic acid copolymer polyflow no. 57, 95 (manufactured by Kyoeisha Chemical Co., Ltd.) or the like can be used.
These surfactants can be used alone or in combination of two or more.
These (F) 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). (F) When the usage-amount of surfactant exceeds 5 weight part, when forming a coating film on a board | substrate, the film run-off of a coating film may arise easily.

  The radiation sensitive resin composition of the present invention can also use an adhesion assistant as component (G) in order to improve the adhesion to the substrate. As such (G) adhesion aid, for example, a functional silane coupling agent is preferably used. Examples thereof include a silane coupling agent having a reactive substituent such as a carboxyl group, a methacryloyl group, an isocyanate group, and an epoxy group. More specifically, for example, trimethoxysilylbenzoic acid, γ-methacryloxypropyltrimethoxysilane, vinyltriacetoxysilane, vinyltrimethoxysilane, γ-isocyanatopropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane , Β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, and the like. Such (G) adhesion assistant 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). In the case where the amount of the adhesion assistant exceeds 20 parts by weight, there may be a case where development residue is likely to occur in the development process.

Radiation-sensitive resin composition The radiation-sensitive resin composition of the present invention is prepared by uniformly mixing the above-described copolymers (A) and (B) and other components optionally added as described above. Is done. The radiation-sensitive resin composition of the present invention is preferably used in a solution state after being dissolved in an appropriate solvent. For example, the radiation sensitive resin composition in a solution state can be prepared by mixing the copolymers (A) and (B) and other components optionally added at a predetermined ratio.
As a solvent used for preparation of the radiation sensitive resin composition of the present invention, each component of the copolymer (A) and (B) components and other components optionally blended is uniformly dissolved, and each component Those that do not react with.
As such a solvent, the thing similar to what was illustrated as a solvent which can be used in order to manufacture the copolymer (A) mentioned above can be mentioned.

Of these solvents, alcohols, glycol ethers, ethylene glycol alkyl ether acetates, esters and diethylene glycol are preferably used from the viewpoints of solubility of each component, reactivity with each component, ease of film formation, and the like. It is done. Among these, for example, benzyl alcohol, 2-phenylethyl alcohol, 3-phenyl-1-propanol, ethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol diethyl ether, diethylene glycol ethyl methyl ether, diethylene glycol dimethyl ether, propylene glycol monomethyl ether Propylene glycol monomethyl ether acetate, methyl methoxypropionate, and ethyl ethoxypropionate can be particularly preferably used.
Furthermore, in order to improve the in-plane uniformity of the film thickness together with the solvent, a high boiling point solvent can be used in combination. Examples of the high boiling point solvent that can be used in combination include N-methylformamide, N, N-dimethylformamide, N-methylformanilide, N-methylacetamide, N, N-dimethylacetamide, N-methylpyrrolidone, dimethylsulfoxide, and benzylethyl ether. , Dihexyl ether, acetonyl acetone, isophorone, caproic acid, caprylic acid, 1-octanol, 1-nonanol, benzyl acetate, ethyl benzoate, diethyl oxalate, diethyl maleate, γ-butyrolactone, ethylene carbonate, propylene carbonate, phenyl Examples include cellosolve acetate. Of these, N-methylpyrrolidone, γ-butyrolactone, and N, N-dimethylacetamide are preferable.

When a high boiling point solvent is used in combination as the solvent of the radiation sensitive resin composition of the present invention, the amount used is preferably 50% by weight or less, more preferably 40% by weight or less, still more preferably 30%, based on the total amount of the solvent. It can be made into weight% or less. When the amount of the high-boiling solvent used exceeds this amount, the coating film thickness uniformity, sensitivity, and residual film rate may be reduced.
When preparing the radiation sensitive resin composition of the present invention in a solution state, the total of components other than the solvent in the solution, that is, the copolymer (A) and (B) components and other components optionally added The ratio of the amount can be arbitrarily set according to the purpose of use, the value of the desired film thickness, etc., for example, 5 to 50% by weight, preferably 10 to 40% by weight, more preferably 15 to 35% by weight. is there.
The composition solution thus prepared can be used after being filtered using a Millipore filter having a pore size of about 0.2 μm.

Formation of Interlayer Insulating Film and Microlens Next, a method for forming the interlayer insulating film and microlens of the present invention using the radiation sensitive resin composition of the present invention will be described. Each method of forming the interlayer insulating film and the microlens of the present invention can be carried out by including the following steps in the order described below.
(1) The process of forming the coating film of the radiation sensitive resin composition of this invention on a board | substrate,
(2) A step of irradiating at least a part of the coating film with radiation,
(3) Development step, and (4) Heating step.

(1) Step of forming a coating film of the radiation sensitive resin composition of the present invention on a substrate In the step of (1) above, the composition solution of the present invention is applied to the substrate surface, preferably prebaked. To remove the solvent and form a coating film of the radiation-sensitive resin composition.
Examples of the types of substrates that can be used include glass substrates, silicon wafers, and substrates on which various metals are formed.
The coating method of the composition solution is not particularly limited, and for example, an appropriate method such as a spray method, a roll coating method, a spin coating method (spin coating method), a slit die coating method, a bar coating method, an ink jet coating method or the like is adopted. In particular, spin coating and slit die coating are preferred. The pre-baking conditions vary depending on the type of each component, the use ratio, and the like. For example, it can be set at 60 to 110 ° C. for about 30 seconds to 15 minutes.
The thickness of the coating film to be formed is, for example, 3 to 6 μm when the interlayer insulating film is formed, and 0.5 to 3 μm, for example, when the microlens is formed, as the value after pre-baking. preferable.

(2) Step of irradiating at least a part of the coating film In the step (2), the formed coating film is irradiated with radiation through a mask having a predetermined pattern. Thereafter, in the next step (3), patterning is performed by developing with a developer to remove the irradiated portion. Examples of the radiation used at this time include ultraviolet rays, far ultraviolet rays, X-rays, and charged particle beams.
Examples of the ultraviolet rays include g-line (wavelength 436 nm), i-line (wavelength 365 nm), and the like. Examples of the far ultraviolet rays include KrF excimer laser. Examples of X-rays include synchrotron radiation. Examples of the charged particle beam include an electron beam.
Among these, ultraviolet rays are preferable, and radiation including g-line and / or i-line is particularly preferable.
Energy of exposure, in the case of forming an interlayer insulating film, for example 50~1,500J / ^{m 2,} in a case of forming a micro-lens, for example, be a 50~2,000J / ^{m 2} Is preferred.

(3) Development process Examples of the developer used in the development process include sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, ammonia, ethylamine, n-propylamine, diethylamine, diethylaminoethanol, di-acid. -N-propylamine, triethylamine, methyldiethylamine, dimethylethanolamine, triethanolamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, pyrrole, piperidine, 1,8-diazabicyclo [5.4.0] -7-undecene An aqueous solution of an alkali (basic compound) such as 1,5-diazabicyclo [4.3.0] -5-nonane can be used. In addition, an aqueous solution obtained by adding an appropriate amount of a water-soluble organic solvent such as methanol or ethanol or a surfactant to the aqueous alkali solution described above, or various organic solvents that dissolve the composition of the present invention can be used as a developing solution. Furthermore, as a developing method, an appropriate method such as a liquid piling method, a dipping method, a rocking dipping method, a shower method, or the like can be used. The development time at this time varies depending on the composition of the composition, but can be, for example, 30 to 120 seconds.
In addition, the conventionally known radiation-sensitive resin composition has been required to strictly control the development time because the formed pattern peels when the development time exceeds about 20 to 25 seconds from the optimum value. In the case of the radiation-sensitive resin composition of the invention, good pattern formation is possible even when the excess time from the optimum development time is 30 seconds or more, and there is an advantage in product yield.

(4) Heating step (3) Performed as described above (3) After the development step, the patterned thin film is preferably rinsed, for example, by washing with running water, and more preferably irradiated with radiation from a high-pressure mercury lamp or the like. (After post-exposure), the 1,2-quinonediazide compound remaining in the thin film is decomposed, and then the thin film is heated (post-baked) with a heating device such as a hot plate or oven. Then, the thin film is cured. The exposure amount in the post-exposure step is preferably about 2,000 to 5,000 J / m ² . Moreover, the heating temperature in this hardening process is 120-250 degreeC, for example. The heating time varies depending on the type of heating device. For example, when heat treatment is performed on a hot plate, the heating time is, for example, 5 to 30 minutes. When heat treatment is performed in an oven, the heating time is, for example, 30 to 90 minutes. Can do. At this time, a step baking method or the like in which a heating process is performed twice or more can be used.
In this way, a patterned thin 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 adhesion, heat resistance, solvent resistance, transparency, and the like, as will be apparent from examples described later.

Interlayer Insulating Film The interlayer insulating film of the present invention formed as described above has good adhesion to the substrate, excellent solvent resistance and heat resistance, high transmittance, and low dielectric constant. Therefore, it can be suitably used as an interlayer insulating film of electronic parts.

The microlens of the present invention formed as described above has good adhesion to the substrate, excellent solvent resistance and heat resistance, and has high transmittance and a good melt shape. It can be suitably used as a microlens for a solid-state imaging device.
The shape of the microlens of the present invention is a semi-convex lens shape as shown in FIG.

The present invention will be described more specifically with reference to synthesis examples and examples. However, the present invention is not limited to the following examples.
<Measurement of molecular weight of copolymer by gel permeation chromatography>
Apparatus: GPC-101 (made by Showa Denko KK)
Column: GPC-KF-801, GPC-KF-802, GPC-KF-804 and GPC-KF-804 combined mobile phase: tetrahydrofuran containing 0.5% by weight of phosphoric acid.

Synthesis example of copolymer (A) Synthesis example 1
A flask equipped with a condenser and a stirrer was charged with 1 part by weight of azobisisobutyronitrile, 4 parts by weight of cumyl dithiobenzoate and 50 parts by weight of diethylene glycol ethyl methyl ether. Subsequently, 20 parts by weight of styrene, 20 parts by weight of methacrylic acid, 20 parts by weight of tricyclo [5.2.1.0 ^2,6 ] decan-8-yl methacrylate, and 40 parts by weight of glycidyl methacrylate were charged, and then gently replaced with nitrogen. Stirring started. The temperature of the solution was raised to 60 ° C., and this temperature was maintained for 24 hours. Then, 3 parts by weight of azobisisobutyronitrile was added, and the mixture was further stirred for 4 hours at 60 ° C., and 200 parts by weight of diethylene glycol ethyl methyl ether was added. A solution of the copolymer (A-1) was obtained. The copolymer (A-1) had a polystyrene equivalent weight average molecular weight (Mw) of 10,000, a molecular weight distribution (Mw / Mn) of 1.4, and a residual monomer content of 2.0% by weight. The solid content concentration of the polymer solution was 29.8% by weight.

Synthesis example 2
A flask equipped with a condenser and a stirrer was charged with 1 part by weight of azoisobutyronitrile, 4 parts by weight of cumyl dithiobenzoate, and 50 parts by weight of diethylene glycol ethyl methyl ether. Subsequently, 16 parts by weight of methacrylic acid, 18 parts by weight of glycidyl methacrylate, ⁶ parts by weight of tricyclo [5.2.1.0 ^2,6 ] decan-8-yl methacrylate, 30 parts by weight of p-vinylbenzylglycidyl ether, polyethylene glycol ( n = 2) After 30 parts by weight of monomethacrylate was charged and purged with nitrogen, stirring was started gently. The temperature of the solution was raised to 60 ° C., and this temperature was maintained for 24 hours. Then, 3 parts by weight of azobisisobutyronitrile was added, and the mixture was further stirred for 4 hours at 60 ° C., and 200 parts by weight of diethylene glycol ethyl methyl ether was added. A solution of a copolymer (A-2) was obtained. The copolymer (A-2) had a polystyrene equivalent weight average molecular weight (Mw) of 11,000, a molecular weight distribution (Mw / Mn) of 1.3, and a residual monomer content of 1.2% by weight. The solid content concentration of the polymer solution obtained here was 30.1% by weight.

Synthesis example 3
A solution of copolymer (A-3) was obtained according to Synthesis Example 1 except that S-cyanomethyl-S-dodecyltrithiocarbonate was used in place of cumyldithiobenzoate in Synthesis Example 1. The copolymer (A-3) had a weight average molecular weight (Mw) in terms of polystyrene of 9,500, a molecular weight distribution (Mw / Mn) of 1.3, and a residual monomer content of 1.5% by weight. The solid content concentration of the polymer solution was 29.6% by weight.

Synthesis example 4
A polymer solution containing the copolymer (A-4) was obtained according to Synthesis Example 2 except that pyrazole-1-dithiocarboxylic acid phenyl-methyl ester was used in place of cumyl dithiobenzoate in Synthesis Example 2. The copolymer (A-4) had a polystyrene equivalent weight average molecular weight (Mw) of 12,000, a molecular weight distribution (Mw / Mn) of 1.4, and a residual monomer content of 1.3% by weight. The solid content concentration of the polymer solution was 29.7% by weight.

Synthesis example 5
In Synthesis Example 1, a polymer solution containing the copolymer (A-5) was obtained according to Synthesis Example 1 except that the following dithioester was used in place of cumyl dithiobenzoate. The copolymer (A-5) had a polystyrene equivalent weight average molecular weight (Mw) of 11,000, a molecular weight distribution (Mw / Mn) of 1.3, and a residual monomer content of 1.4% by weight. The solid content concentration of the polymer solution was 29.8% by weight.

Synthesis Example 6
In Synthesis Example 2, a polymer solution containing the copolymer (A-6) was obtained according to Synthesis Example 2 except that the following xanthate was used in place of cumyldithiobenzoate. The copolymer (A-6) had a polystyrene equivalent weight average molecular weight (Mw) of 11,000, a molecular weight distribution (Mw / Mn) of 1.3, and a residual monomer content of 1.5% by weight. The solid content concentration of the polymer solution was 30.1% by weight.

Comparative Synthesis Example 1
A flask equipped with a condenser and a stirrer was charged with 8 parts by weight of 2,2′-azobis (2,4-dimethylvaleronitrile) and 220 parts by weight of diethylene glycol ethyl methyl ether. Subsequently, 20 parts by weight of styrene, 20 parts by weight of methacrylic acid, 40 parts by weight of glycidyl methacrylate and 20 parts by weight of phenylmaleimide were charged and purged with nitrogen, and then gently stirring was started. The temperature of the solution was raised to 70 ° C., and this temperature was maintained for 5 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 7,500 and a molecular weight distribution (Mw / Mn) of 2.4. The residual monomer was 5.8% by weight. Moreover, the solid content concentration of the polymer solution obtained here was 30.6% by weight.

Example 1
Preparation of Radiation Sensitive Resin Composition A solution containing polymer (A-1) as component (A) synthesized in Synthesis Example 1 corresponds to 100 parts by weight (solid content) of polymer (A-1). 4,4 '-[1- [4- [1- [4-hydroxyphenyl] -1-methylethyl] phenyl] ethylidene] bisphenol (1.0 mol) and 1,2- as component (B) After mixing 30 parts by weight of naphthoquinonediazide-5-sulfonic acid chloride (2.0 mol) condensate (B-1) and dissolving in diethylene glycol ethyl methyl ether so that the solid content concentration is 30% by weight The solution was filtered through a membrane filter having a diameter of 0.2 μm to prepare a solution (S-1) of a radiation sensitive resin composition.

Examples 2-9, 11-14, Comparative Example 1
Preparation of Radiation Sensitive Resin Composition In Example 1, as the component (A) and the component (B), except that the types and amounts shown in Table 1 were used, the same as in Example 1, Solutions (S-2) to (S-9), (S-11) to (S-14), and (s-1) of the radiation sensitive resin composition were prepared.
In Table 1, the description of the component (B) in Example 8 indicates that two types of 1,2-quinonediazide compounds B-1 (20 parts by weight) and B-2 (15 parts by weight) were used in combination. it's shown.

Example 10
In Example 1, a composition was prepared in the same manner as in Example 1 except that it was dissolved in diethylene glycol ethyl methyl ether so that the solid content concentration was 15% by weight, and a solution of radiation sensitive resin composition (S-10) Was prepared.
In Table 1, the abbreviations of the components indicate the following compounds.
(B-1): 4,4 ′-[1- [4- [1- [4-Hydroxyphenyl] -1-methylethyl] phenyl] ethylidene] bisphenol (1.0 mol) and 1,2-naphthoquinonediazide Condensate (B-2) of -5-sulfonic acid chloride (2.0 mol): 4,4 ′-[1- [4- [1- [4-hydroxyphenyl] -1-methylethyl] phenyl] ethylidene Condensate of bisphenol (1.0 mol) and 1,2-naphthoquinonediazide-5-sulfonic acid chloride (1.0 mol) (B-3): 2,3,4,4′-tetrahydroxybenzophenone (1 .0 mol) and 1,2-naphthoquinonediazide-5-sulfonic acid ester (2.44 mol)
(B-4): 4,4 ′-[1- [4- [1- [4-hydroxyphenyl] -1-methylethyl] phenyl] ethylidene] bisphenol (1.0 mol) and 1,2-naphthoquinonediazide -4-Sulphonic acid chloride (2.0 mol) condensate (F): SH-28PA (manufactured by Dow Corning Toray Silicone Co., Ltd.)

Examples 15-28, Comparative Examples 2-4
Performance Evaluation as Interlayer Insulating Film Using the radiation sensitive resin composition prepared as described above, various characteristics as an interlayer insulating film were evaluated as follows. The compositions used in Comparative Examples 3 and 4 are all commercial products of a composition of m / p-cresol novolak and 1,2-naphthoquinonediazide-5-sulfonic acid ester (manufactured by Tokyo Ohka Kogyo Co., Ltd.). It is.

Evaluation of Sensitivity After applying the composition described in Table 2 on a silicon substrate, using Examples 15 to 27, Comparative Examples 2 to 4 using a spinner, and Example 28 using a slit die coater, The film was prebaked on a hot plate at 90 ° C. for 2 minutes to form a coating film having a thickness of 3.0 μm. After the exposure time was changed with a PLA-501F exposure machine (extra-high pressure mercury lamp) manufactured by Canon Inc., through a pattern mask having a predetermined pattern, the obtained coating film was listed in Table 2. Development was performed by a puddle method at 25 ° C. for 90 seconds with an aqueous tetramethylammonium hydroxide solution having a developer concentration. The substrate was washed with ultrapure water for 1 minute and dried to form a pattern on the wafer. The amount of exposure required to completely dissolve the 3.0 μm line-and-space (10 to 1) space pattern was measured. This value is shown in Table 2 as sensitivity. It can be said that the sensitivity is good when this value is 1,000 J / m ² or less.

Evaluation of Development Margin After applying the compositions shown in Table 2 on a silicon substrate using Examples 15 to 27 and Comparative Examples 2 to 4 using a spinner, and Example 28 using a slit die coater. The film was pre-baked on a hot plate at 90 ° C. for 2 minutes to form a coating film having a thickness of 3.0 μm. Using a PLA-501F exposure machine (extra-high pressure mercury lamp) manufactured by Canon Inc. through a mask having a 3.0 μm line and space (10: 1) pattern on the obtained coating film, Exposure was carried out with an exposure amount corresponding to the sensitivity value measured in “Evaluation of Sensitivity”, and development was performed by a puddle method at 25 ° C. for 90 seconds with an aqueous tetramethylammonium hydroxide solution having the developer concentration shown in Table 2. Subsequently, the substrate was washed with ultrapure water for 1 minute and dried to form a pattern on the wafer. At this time, the development time required for the line width to be 3 μm is shown in Table 2 as the optimum development time. Further, when the development was further continued from the optimum development time, the time until the 3.0 μm line pattern was peeled off was measured and shown in Table 2 as a development margin. When this value is 30 seconds or more, it can be said that the development margin is good.

Evaluation of solvent resistance The compositions described in Table 2 were applied on a silicon substrate using Examples 15 to 27 and Comparative Examples 2 to 4 using a spinner, and Example 28 using a slit die coater. Then, it prebaked on a hot plate at 90 ° C. for 2 minutes to form a coating film having a thickness of 3.0 μm. The obtained coating film was exposed to a cumulative irradiation amount of 3,000 J / m ² with a PLA-501F exposure machine (extra-high pressure mercury lamp) manufactured by Canon Inc., and this silicon substrate was exposed to 220 in a clean oven. A cured film was obtained by heating at 0 ° C. for 1 hour. The film thickness (T1) of the obtained cured film was measured. And after immersing the silicon substrate in which this cured film was formed in dimethyl sulfoxide temperature-controlled at 70 degreeC for 20 minutes, the film thickness (t1) of the said cured film was measured, and the film thickness change rate by immersion { | T1-T1 | / T1} × 100 [%] was calculated. The results are shown in Table 2. When this value is 5% or less, the solvent resistance is good.
In the evaluation of solvent resistance, since the patterning of the film to be formed is unnecessary, the radiation irradiation process and the development process were omitted, and only the coating film forming process, the post-baking process, and the heating process were performed for evaluation.

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

Evaluation of Transparency In the evaluation of solvent resistance, a cured film was formed on the glass substrate in the same manner except that a glass substrate “Corning 7059 (manufactured by Corning)” was used instead of the silicon substrate. The light transmittance of the glass substrate having this cured film was measured at a wavelength in the range of 400 to 800 nm using a spectrophotometer “150-20 type double beam (manufactured by Hitachi, Ltd.)”. Table 2 shows the values of the minimum light transmittance at that time. When this value is 90% or more, it can be said that the transparency is good.

Evaluation of relative permittivity Compositions listed in Table 2 on a polished SUS304 substrate using Examples 15 to 27, Comparative Examples 2 to 4 using a spinner, and Example 28 using a slit die coater Then, it was pre-baked on a hot plate at 90 ° C. for 2 minutes to form a coating film having a thickness of 3.0 μm. The obtained coating film was exposed with a PLA-501F exposure machine (extra-high pressure mercury lamp) manufactured by Canon Co., Ltd. so that the integrated irradiation amount was 3,000 J / m ^2, and this substrate was 220 ° C. in a clean oven. The cured film was obtained by baking for 1 hour.
About this cured film, the Pt / Pd electrode pattern was formed by the vapor deposition method, and the sample for dielectric constant measurement was created. The relative dielectric constant of the substrate was measured at a frequency of 10 kHz by a CV method using an HP16451B electrode and an HP4284A precision LCR meter manufactured by Yokogawa-Hewlett-Packard Co., Ltd. The results are shown in Table 2. When this value is 3.6 or less, it can be said that the relative dielectric constant is good.
In the evaluation of the relative dielectric constant, since the patterning of the film to be formed is unnecessary, the radiation irradiation process and the development process were omitted, and only the coating film forming process, the post-baking process, and the heating process were performed for evaluation.

Evaluation of Sublimate After applying the composition described in Table 2 on a silicon substrate using Examples 15-27 and Comparative Examples 2-4 using a spinner, and Example 28 using a slit die coater. The film was pre-baked on a hot plate at 90 ° C. for 2 minutes to form a coating film having a thickness of 3.0 μm. The obtained coating film was exposed to a cumulative irradiation amount of 3,000 J / m ² with a PLA-501F exposure machine (extra-high pressure mercury lamp) manufactured by Canon Inc., and this silicon substrate was exposed to 220 in a clean oven. A cured film was obtained by heating at 0 ° C. for 1 hour. A bare silicon wafer for cooling was mounted at an interval of 1 cm above the obtained cured film, and a heating process was performed at 230 ° C. for 1 hour on a hot plate. Without replacing the bare silicon wafer for cooling, 20 silicon substrates on which the cured film was separately formed were processed in succession, and then the presence or absence of sublimated material adhering to the bare silicon was verified visually. When the sublimate is not confirmed, the sublimate evaluation is good.

Examples 29-42, Comparative Examples 5-7
<Performance evaluation as a micro lens>
Using the radiation-sensitive resin composition prepared as described above, various characteristics as a microlens were evaluated as follows. For the evaluation of heat resistance and transparency, refer to the results (Table 2) in the performance evaluation as the interlayer insulating film.
In addition, the compositions used in Comparative Examples 6 and 7 are all commercially available products (manufactured by Tokyo Ohka Kogyo Co., Ltd.) of m / p-cresol novolak and 1,2-naphthoquinonediazide-5-sulfonic acid ester. It is.

Evaluation of sensitivity On a silicon substrate, the compositions described in Table 3 were prepared using a spinner for Examples 29 to 38, 40 to 42 and Comparative Examples 5 to 7, and using a slit die coater for Example 39. After coating, it was pre-baked on a hot plate at 90 ° C. for 2 minutes to form a coating film having a thickness of 3.0 μm. The obtained coating film was exposed with a NSR1755i7A reduction projection exposure machine (NA = 0.50, λ = 365 nm) manufactured by Nikon Corporation through a pattern mask having a predetermined pattern. Development was carried out by a puddle method at 25 ° C. for 1 minute in an aqueous tetramethylammonium hydroxide solution having the developer concentration described. It was rinsed with water and dried to form a pattern on the wafer. The exposure time required for the space line width of the 0.8 μm line and space pattern (1 to 1) to be 0.8 μm was measured. This value is shown in Table 3 as sensitivity. It can be said that the sensitivity is good when this value is 2,500 J / m ² or less.

Evaluation of Development Margin A composition described in Table 3 on a silicon substrate using Examples 29-38, 40-42, Comparative Examples 5-7 using a spinner, and Example 39 using a slit die coater. Then, it was pre-baked on a hot plate at 90 ° C. for 2 minutes to form a coating film having a thickness of 3.0 μm. The sensitivity measured in the above “Evaluation of Sensitivity” with a NSR1755i7A reduction projection exposure machine (NA = 0.50, λ = 365 nm) manufactured by Nikon Corporation through a pattern mask having a predetermined pattern on the obtained coating film. Exposure was carried out with an exposure amount corresponding to the value, and development was carried out by a puddle method at 25 ° C. for 1 minute in a tetramethylammonium hydroxide aqueous solution having a developer concentration shown in Table 3. It was rinsed with water and dried to form a pattern on the wafer. Table 3 shows the development time necessary for the space line width of 0.8 μm line and space pattern (one to one) to be 0.8 μm as the optimum development time. Further, the time (development margin) until the pattern having a width of 0.8 μm was peeled off when the development was further continued from the optimum development time was shown in Table 3 as the development margin. When this value is 30 seconds or more, it can be said that the development margin is good.

Evaluation of solvent resistance Compositions listed in Table 3 on a silicon substrate using Examples 29 to 38, 40 to 42, Comparative Examples 5 to 7 using a spinner, and Example 39 using a slit die coater After applying the product, it was pre-baked on a hot plate at 90 ° C. for 2 minutes to form a coating film having a thickness of 3.0 μm. The obtained coating film was exposed to a cumulative irradiation amount of 3,000 J / m ² with a PLA-501F exposure machine (extra-high pressure mercury lamp) manufactured by Canon Inc., and this silicon substrate was exposed to 220 in a clean oven. A cured film was obtained by heating at 0 ° C. for 1 hour. The film thickness (T3) of the obtained cured film was measured. And after immersing the silicon substrate in which this cured film was formed in isopropyl alcohol temperature-controlled at 50 degreeC for 10 minutes, the film thickness (t3) of the said cured film was measured, and the film thickness change rate by immersion { | T3-T3 | / T3} × 100 [%] was calculated. The results are shown in Table 3. When this value is 5% or less, the solvent resistance is good.
In the evaluation of solvent resistance, since the patterning of the film to be formed is unnecessary, the radiation irradiation process and the development process were omitted, and only the coating film forming process, the post-baking process, and the heating process were performed for evaluation.

Formation of microlenses Compositions described in Table 3 on a silicon substrate using Examples 29 to 38, 40 to 42, Comparative Examples 5 to 7 using a spinner, and Example 39 using a slit die coater Then, it was pre-baked on a hot plate at 90 ° C. for 2 minutes to form a coating film having a thickness of 3.0 μm. The obtained coating film was passed through a pattern mask having 4.0 [mu] m dots and 2.0 [mu] m space pattern with a NSR1755i7A reduction projection exposure machine (NA = 0.50, [lambda] = 365 nm) manufactured by Nikon Corporation. Exposure is performed at an exposure amount corresponding to the sensitivity value measured in “Evaluation of Sensitivity”, and a solution is added at 25 ° C. for 1 minute in a tetramethylammonium hydroxide aqueous solution having a concentration described as the developer concentration in the sensitivity evaluation of Table 3. Developed by prime method. It was rinsed with water and dried to form a pattern on the wafer. Then, it exposed so that the integrated irradiation amount might be set to 3,000 J / m < ² > with the PLA-501F exposure machine (extra-high pressure mercury lamp) by Canon. Thereafter, the pattern was melt-flowed by heating at 160 ° C. for 10 minutes on a hot plate and further at 230 ° C. for 10 minutes to form a microlens.
Table 3 shows the size (diameter) and cross-sectional shape of the bottom (surface contacting the substrate) of the formed microlens. It can be said that the microlens bottom portion is good when it is larger than 4.0 μm and smaller than 5.0 μm. In addition, when this dimension is 5.0 μm or more, the adjacent lenses are in contact with each other, which is not preferable. Further, the cross-sectional shape is good when it is a semi-convex lens shape as shown in (a) in the schematic diagram shown in FIG. 1, and it is bad when it is on a substantially trapezoidal shape as shown in (b).

The radiation-sensitive resin composition of the present invention has high radiation sensitivity, has a development margin that can form a good pattern shape even when the optimum development time is exceeded in the development process, and has excellent adhesion. A patterned thin film can be easily formed, and sublimates generated during firing are reduced.
The interlayer insulating film of the present invention formed from the above composition has good adhesion to the substrate, excellent solvent resistance and heat resistance, high transmittance, low dielectric constant, and interlayer between electronic components. It can be suitably used as an insulating film.
In addition, the microlens of the present invention formed from the upper composition has good adhesion to the substrate, excellent solvent resistance and heat resistance, high transmittance and good melt shape, and solid-state imaging It can be suitably used as a microlens for the element.

Claims (8)

(A) A copolymer obtained by living radical polymerization using a thiocarbonylthio compound as a control agent, having a carboxyl group and an epoxy group, and having a weight average molecular weight in terms of polystyrene (Mw) measured by gel permeation chromatography ) and the ratio of polystyrene-reduced number average molecular weight (Mn) (Mw / Mn) is co-polymer with 1.7 or less, and (B) a radiation-sensitive resin which is characterized by containing a 1,2-quinonediazide compound Composition. The copolymer (A) is (a1) an unsaturated carboxylic acid and / or an unsaturated carboxylic acid anhydride,
The feeling according to claim 1, obtained by living radical polymerization of a polymerizable mixture containing (a2) an epoxy group-containing unsaturated compound and (a3): an unsaturated compound other than (a1) and (a2). Radiation resin composition. The radiation-sensitive resin composition according to claim 1, which is used for forming an interlayer insulating film. A method for forming an interlayer insulating film, wherein the following steps are performed in the order described below.
(1) The process of forming the coating film of the radiation sensitive resin composition of Claim 1 on a board | substrate,
(2) A step of irradiating at least a part of the coating film with radiation,
(3) Development step, and (4) Heating step. An interlayer insulating film formed by the method according to claim 4 . The radiation-sensitive resin composition according to claim 1, which is used for forming a microlens. A method for forming a microlens comprising the following steps in the following order:
(1) The process of forming the coating film of the radiation sensitive resin composition of Claim 1 on a board | substrate,
(2) A step of irradiating at least a part of the coating film with radiation,
(3) Development step, and (4) Heating step. A microlens formed by the method of claim 7 .

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