JP4656316B2 - Interlayer insulating film, microlens, and manufacturing method thereof - Google Patents

Description

The present invention is a layer insulating film and the microlens, and methods for their preparation.

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. Therefore, the microlens or the microlens array requires solvent resistance and heat resistance in the flattening film and 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. On the other hand, when forming a microlens, a good melt shape (desired radius of curvature), high heat resistance, high solvent resistance, and high transmittance are required as the microlens. A radiation-sensitive resin composition satisfying the above has not been conventionally known.
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 .

The purpose of the present invention has a high-sensitive radiation sensitivity, even beyond the optimum developing time in the development step Note a developing margin that can form a good pattern profile, good patterned thin film adhesion It can be easily formed, and when used to form an interlayer insulating film, it can form an interlayer insulating film having high heat resistance, high solvent resistance, high transmittance, and low dielectric constant. When used, it is an object to provide a method for forming an interlayer insulating film and a microlens using a radiation sensitive resin composition capable of forming a microlens having a high transmittance and a good melt shape .
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 firstly
This is achieved by a method for forming an interlayer insulating film or a microlens, which includes the following steps in the order described below.
(1) [A] (a1) an unsaturated carboxylic acid and / or an unsaturated carboxylic anhydride (hereinafter sometimes referred to as “compound (a1)”),
(A2) an epoxy group-containing unsaturated compound (hereinafter sometimes referred to as “compound (a2)”),
(A3) Formula (I) below

Here, R ¹ is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, R ^{2 to} R ⁶ are the same or different, and are a hydrogen atom, a hydroxyl group or an alkyl group having 1 to 4 carbon atoms, and B is a single atom. A bond, —COO—, or —CONH—, and m is an integer of 0 to 3, provided that at least one of R ^{2 to} R ⁶ is a hydroxyl group.
And (a4) a copolymer of an unsaturated compound other than (a4) (a1), (a2) and (a3) (hereinafter sometimes referred to as “compound (a4)”). Hereinafter, it may be referred to as “copolymer [A]”), and [B] 1,2-quinonediazide compound (hereinafter also referred to as “[B] component”). Forming a coating film of a radiation sensitive resin composition on a substrate;
(2) A step of irradiating at least a part of the coating film with radiation,
(3) Development process, and
(4) Heating process.

Secondly, the objects and advantages of the present invention are:
This is achieved by a method for forming an interlayer insulating film or a microlens, which includes the following steps in the order described below.
(1) The process of forming the coating film of said radiation sensitive 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 objects and advantages of the present invention in the second,
This is achieved by the interlayer insulating film or microlens formed by the above method.

The radiation-sensitive resin composition in 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.
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, It can be suitably used as an interlayer insulating film for parts.
Further, the microlens of the present invention formed from the upper composition has good adhesion to the substrate, excellent solvent resistance and heat resistance, and has a high transmittance and a good melt shape, It can be suitably used as a microlens for a solid-state image sensor.

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

Copolymer [A]
Copolymer [A] can be produced by radical polymerization of compound (a1), compound (a2), compound (a3), and compound (a4) in the presence of a polymerization initiator in a solvent. In the copolymer [A] used in the present invention, the structural unit derived from the compound (a1) is added to the total of repeating units derived from the compounds (a1), (a2), (a3) and (a4). Based on this, the content is preferably 5 to 40% by weight, particularly preferably 10 to 30% by weight. When a copolymer having a constitutional 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;
As anhydrides of dicarboxylic acids, for example, anhydrides of the compounds exemplified as the above dicarboxylic acids;
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 the mono (meth) acrylate of a polymer having a carboxyl group and a hydroxyl group at 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, 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] 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 compounds (a1) are used alone or in combination.
In the copolymer [A] used in the present invention, the structural unit derived from the compound (a2) is added to the total number of repeating units derived from the compounds (a1), (a2), (a3) and (a4). Based on this, the content is preferably 10 to 80% by weight, particularly preferably 20 to 70% by weight. When this structural 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, whereas when the amount of this structural unit exceeds 80% by weight, the radiation sensitive resin The storage stability of the composition tends to decrease.

  Compound (a2) is an epoxy group-containing unsaturated compound having radical polymerizability, such as glycidyl acrylate, glycidyl methacrylate, glycidyl α-ethyl acrylate, glycidyl α-n-propyl acrylate, α-n-butyl acryl. Glycidyl acid, acrylic acid-3,4-epoxybutyl, methacrylic acid-3,4-epoxybutyl, acrylic acid-6,7-epoxyheptyl, methacrylic acid-6,7-epoxyheptyl, α-ethylacrylic acid-6 , 7-epoxyheptyl, o-vinylbenzyl glycidyl ether, m-vinylbenzyl glycidyl ether, p-vinylbenzyl glycidyl ether, and the like. 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 compounds (a2) are used alone or in combination.

In the copolymer [A] used in the present invention, the structural unit derived from the compound (a3) is added to the total number of repeating units derived from the compounds (a1), (a2), (a3) and (a4). The content is preferably 1 to 50% by weight, particularly preferably 3 to 40% by weight. When this structural unit is less than 1% by weight, the sensitivity of the radiation-sensitive resin composition tends to decrease. On the other hand, when it exceeds 50% by weight, an alkaline aqueous solution is used in the development step in forming an interlayer insulating film or microlens. There is a tendency that the solubility in is too large.
Compound (a3) is an unsaturated compound containing a phenol skeleton and having radical polymerizability, and has the following formula (I)

Here, R ¹ is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, R ^{2 to} R ⁶ are the same or different, and are a hydrogen atom, a hydroxyl group or an alkyl group having 1 to 4 carbon atoms, and B is a single atom. A bond, —COO—, or —CONH—, and m is an integer of 0 to 3, provided that at least one of R ^{2 to} R ⁶ is a hydroxyl group.
It is represented by
The compounds represented by the above formula (I) can be classified into compounds represented by the following formulas (1) to (5) according to the definitions of B and m.

(In formula (1), n is an integer of 1 to 3, and the definitions of R ¹ , R ² , R ³ , R ⁴ , R ⁵ , and R ⁶ are the same as in formula (I).)

(In formula (2), the definitions of R ¹ , R ² , R ³ , R ⁴ , R ⁵ , and R ⁶ are the same as those in formula (I) above.)

(In Formula (3), n is an integer of 1 to 3. The definitions of R ¹ , R ² , R ³ , R ⁴ , R ⁵ , and R ⁶ are the same as those in Formula (I) above.)

(In formula (4), the definitions of R ¹ , R ² , R ³ , R ⁴ , R ⁵ , and R ⁶ are the same as those in formula (I) above.)

(In formula (5), the definitions of R ¹ , R ² , R ³ , R ⁴ , R ⁵ , and R ⁶ are the same as those in formula (I) above.)
Among these, N- (3,5-dimethyl-4-hydroxybenzyl) (meth) acrylamide, N- (4-hydroxyphenyl) (meth) acrylamide, 4-hydroxybenzyl (meth) acrylate, 4-hydroxyphenyl ( (Meth) acrylate, o-hydroxystyrene, m-hydroxystyrene, p-hydroxystyrene, α-methyl-o-hydroxystyrene, α-methyl-m-hydroxystyrene, α-methyl-p-hydroxystyrene are radiation sensitive resins. It is preferably used from the viewpoint of increasing the sensitivity of the composition, widening the development margin, and improving heat resistance. These may be used alone or in combination.

  In the copolymer [A] used in the present invention, the structural unit derived from the compound (a4) is added to the total repeating units derived from the compounds (a1), (a2), (a3) and (a4). Based on this, it is preferably 5 to 70% by weight, particularly preferably 5 to 50% by weight. When this structural unit is less than 5% by weight, the storage stability of the radiation-sensitive resin composition tends to be lowered. On the other hand, when it exceeds 70% by weight, in the development step in forming an interlayer insulating film or microlens, It may be difficult to dissolve in an alkaline aqueous solution.

  The compound (a4) is not particularly limited as long as it is an unsaturated compound having radical polymerizability. For example, methacrylic acid alkyl ester, methacrylic acid cyclic alkyl ester, methacrylic acid cyclic alkyl ester, methacrylic acid ester having a hydroxyl group, acrylic acid cyclic alkyl ester, methacrylic acid aryl ester, acrylic acid aryl ester, unsaturated dicarboxylic acid diester, bicyclo An unsaturated compound, a maleimide compound, an unsaturated aromatic compound, a conjugated diene, a tetrahydrofuran skeleton, a furan skeleton, a tetrahydropyran skeleton, a pyran skeleton, an unsaturated compound having a skeleton represented by the following formula (6), and other unsaturated compounds Can be mentioned.

(In formula (6), R ⁷ is a hydrogen atom or a methyl group)
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 .;
Methacrylic acid cyclic alkyl esters such as methyl acrylate and isopropyl acrylate;
Examples of the methacrylic acid cyclic alkyl ester 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 the cyclic alkyl ester of acrylic acid 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 (cyclohex Siloxycarbonyl) 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 N-phenylmaleimide, N-cyclohexylmaleimide, N-benzylmaleimide, N- (4-hydroxyphenyl) maleimide, N- (4-hydroxybenzyl) maleimide, N-succinimidyl-3-maleimidobenzoate, N -Succinimidyl-4-maleimidobutyrate, N-succinimidyl-6-maleimidocaproate, N-succinimidyl-3-maleimidopropionate, 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 unsaturated compounds containing a tetrahydrofuran skeleton include tetrahydrofurfuryl (meth) acrylate, 2-methacryloyloxy-propionic acid tetrahydrofurfuryl ester, and 3- (meth) acryloyloxytetrahydrofuran-2-one;
Examples of unsaturated compounds containing a furan skeleton include 2-methyl-5- (3-furyl) -1-penten-3-one, furfuryl (meth) acrylate, 1-furan-2-butyl-3-ene-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 --Hexyl-1-en-3-one, 2-furan-2-yl-1-yl-methyl-ethyl ester, 6- (2-furyl) -6-methyl-1-heptene- 3-on etc .;
Examples of unsaturated compounds containing a tetrahydropyran skeleton include (tetrahydropyran-2-yl) methyl methacrylate, 2,6-dimethyl-8- (tetrahydropyran-2-yloxy) -oct-1-en-3-one, 2-methacrylic acid tetrahydropyran-2-yl ester, 1- (tetrahydropyran-2-oxy) -butyl-3-en-2-one, etc .;
Examples of unsaturated compounds containing a pyran skeleton include 4- (1,4-dioxa-5-oxo-6-heptenyl) -6-methyl-2-pyrone, 4- (1,5-dioxa-6-oxo- 7-octenyl) -6-methyl-2-pyrone and the like;
Examples of unsaturated compounds containing a skeleton represented by the above formula (6) include polyethylene glycol (n = 2 to 10) mono (meth) acrylate, polypropylene glycol (n = 2 to 10) mono (meth) acrylate, 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 in particular, styrene, t-butyl methacrylate, tricyclo [5.2.1.0]. ^2,6 ] decan-8-yl methacrylate, p-methoxystyrene, 2-methylcyclohexyl acrylate, 1,3-butadiene, bicyclo [2.2.1] hept-2-ene, tetrahydrofurfuryl (meth) acrylate, Polyethylene glycol (n = 2 to 10) mono (meth) acrylate, 3- (meth) acryloyloxytetrahydrofuran-2-one, 1- (tetrahydropyran-2-oxy) -butyl-3-en-2-one, furfuryl (Meth) acrylate is copolymerization reactive and alkaline water It is preferable from the viewpoint of solubility in a solution. These compounds (a4) are used alone or in combination.

Preferable specific examples of the copolymer [A] used in the present invention include, for example, methacrylic acid / tricyclo [5.2.1.0 ^2,6 ] decan-8-yl methacrylate / glycidyl methacrylate / 2-methyl. Cyclohexyl acrylate / N- (3,5-dimethyl-4-hydroxybenzyl) methacrylamide copolymer, methacrylic acid / glycidyl methacrylate / 1- (tetrahydropyran-2-oxy) -butyl-3-en-2-one / N-cyclohexylmaleimide / p-methoxystyrene / N- (3,5-dimethyl-4-hydroxybenzyl) methacrylamide copolymer, methacrylic acid / glycidyl methacrylate / tricyclo [5.2.1.0 ^2,6 ] Decan-8-yl methacrylate / styrene / N-phenylmaleimide / N- (4-hydroxy) Phenyl) methacrylamide copolymer, methacrylic acid / glycidyl methacrylate / tricyclo [5.2.1.0 ^2,6 ] decan-8-yl methacrylate / n-lauryl methacrylate / 3-methacryloyloxytetrahydrofuran-2-one / N- (4-hydroxyphenyl) methacrylamide copolymer, methacrylic acid / glycidyl methacrylate / styrene / 2-methylcyclohexyl acrylate / 1- (tetrahydropyran-2-oxy) -butyl-3-en-2-one / 4-hydroxybenzyl methacrylate copolymer, methacrylic acid / glycidyl methacrylate / tricyclo [5.2.1.0 ^2,6 ] decan-8-yl methacrylate / p-methoxystyrene / 4-hydroxybenzyl methacrylate copolymer, Methacrylic acid / Trishik B [5.2.1.0 ^2,6 ] decan-8-yl methacrylate / glycidyl methacrylate / styrene / p-vinylbenzyl glycidyl ether / tetrahydrofurfuryl methacrylate / 4-hydroxyphenyl methacrylate copolymer, methacrylic acid / Glycidyl methacrylate / N-cyclohexylmaleimide / 3-methacryloyloxytetrahydrofuran-2-one / tetrahydrofurfuryl methacrylate / 4-hydroxyphenyl methacrylate copolymer, methacrylic acid / glycidyl methacrylate / tetrahydrofurfuryl methacrylate / N-phenylmaleimide / α- methyl -p- hydroxystyrene copolymer, methacrylic acid / glycidyl methacrylate / tricyclo [5.2.1.0 ^2,6] decan-8-yl methacrylate / N- Black hexyl maleimide / n-lauryl methacrylate / alpha-methyl -p- hydroxystyrene copolymer.

The copolymer [A] used in the present invention has a polystyrene-reduced weight average molecular weight (hereinafter referred to as “Mw”), 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. On the other hand, if it exceeds 1 × 10 ⁵ , the sensitivity may be lowered or the pattern shape may be inferior. The molecular weight distribution (hereinafter referred to as “Mw / Mn”) is preferably 5.0 or less, more preferably 3.0 or less. When Mw / Mn exceeds 5.0, the pattern shape of the obtained interlayer insulating film or microlens may be inferior. The radiation-sensitive resin composition containing the copolymer [A] can easily form a predetermined pattern shape without causing a development residue during development.

  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;
Tetrahydrofuran as ethers;
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;
As propylene glycol alkyl ether propionate, for example, propylene glycol methyl ether acetate, propylene glycol ethyl ether acetate, propylene glycol propyl ether acetate, propylene glycol butyl ether acetate and the like;
As propylene glycol alkyl ether acetate, 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, and diethylene glycol dimethyl ether, diethylene glycol ethyl methyl ether, propylene glycol methyl ether, and propylene glycol methyl ether acetate are particularly preferable.

  As the polymerization initiator used in the production of the copolymer [A], 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) Azo compounds such as benzoyl peroxide, lauroyl peroxide, t-butyl peroxypivalate, organic peroxides such as 1,1′-bis- (t-butylperoxy) cyclohexane, and hydrogen peroxide. When a peroxide is used as the radical polymerization initiator, the peroxide may be used together with a reducing agent to form a redox initiator.

  In the production of the copolymer [A], a molecular weight modifier can be used to adjust the molecular weight. Specific examples thereof include halogenated hydrocarbons such as chloroform and carbon tetrabromide; mercaptans such as n-hexyl mercaptan, n-octyl mercaptan, n-dodecyl mercaptan, tert-dodecyl mercaptan and thioglycolic acid; dimethylxanthogen Xanthogens such as sulfide and diisopropylxanthogen disulfide; terpinolene, α-methylstyrene dimer and the like.

[B] Component The [B] component 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;
As tetrahydroxybenzophenone, 2,2 ′, 4,4′-tetrahydroxybenzophenone, 2,3,4,3′-tetrahydroxybenzophenone, 2,3,4,4′-tetrahydroxybenzophenone, 2,3,4 2,2'-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% is used with respect to the number of OH groups in the phenolic compound or alcoholic compound. be able to.
The condensation reaction can be carried out by a known method.
These [B] components 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 in the present invention contains the above-mentioned copolymer [A] and [B] components as essential components, but [C] a heat-sensitive acid generating compound, [ D] A polymerizable compound having at least one ethylenically unsaturated double bond, an epoxy resin other than [E] copolymer [A], [F] an adhesion assistant, or [G] a surfactant. be able to.
[C] The heat-sensitive 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 alkylsulfonium salts such as 4-acetophenyldimethylsulfonium hexafluoroantimonate, 4-acetoxyphenyldimethylsulfonium hexafluoroarsenate, dimethyl-4- (benzyloxycarbonyloxy) phenylsulfonium hexafluoroantimony. Dimethyl-4- (benzoyloxy) phenylsulfonium hexafluoroantimonate, dimethyl-4- (benzoyloxy) phenylsulfonium hexafluoroarsenate, dimethyl-3-chloro-4-acetoxyphenylsulfonium hexafluoroantimonate, etc .;
Examples of benzylsulfonium salts include benzyl-4-hydroxyphenylmethylsulfonium hexafluoroantimonate, benzyl-4-hydroxyphenylmethylsulfonium hexafluorophosphate, 4-acetoxyphenylbenzylmethylsulfonium hexafluoroantimonate, and benzyl-4-methoxyphenylmethyl. Sulfonium hexafluoroantimonate, benzyl-2-methyl-4-hydroxyphenylmethylsulfonium hexafluoroantimonate, benzyl-3-chloro-4-hydroxyphenylmethylsulfonium hexafluoroarsenate, 4-methoxybenzyl-4-hydroxyphenylmethyl Sulfonium hexafluorophosphate, etc .;
Examples of the dibenzylsulfonium salt include dibenzyl-4-hydroxyphenylsulfonium hexafluoroantimonate, dibenzyl-4-hydroxyphenylsulfonium hexafluorophosphate, 4-acetoxyphenyldibenzylsulfonium hexafluoroantimonate, dibenzyl-4-methoxyphenylsulfonium hexa Fluoroantimonate, dibenzyl-3-chloro-4-hydroxyphenylsulfonium hexafluoroarsenate, dibenzyl-3-methyl-4-hydroxy-5-tert-butylphenylsulfonium hexafluoroantimonate, benzyl-4-methoxybenzyl-4 -Hydroxyphenylsulfonium hexafluorophosphate and the like;
Examples of substituted benzylsulfonium salts include p-chlorobenzyl-4-hydroxyphenylmethylsulfonium hexafluoroantimonate, p-nitrobenzyl-4-hydroxyphenylmethylsulfonium hexafluoroantimonate, and p-chlorobenzyl-4-hydroxyphenylmethylsulfonium. Hexafluorophosphate, p-nitrobenzyl-3-methyl-4-hydroxyphenylmethylsulfonium hexafluoroantimonate, 3,5-dichlorobenzyl-4-hydroxyphenylmethylsulfonium hexafluoroantimonate, o-chlorobenzyl-3-chloro Examples thereof include -4-hydroxyphenylmethylsulfonium hexafluoroantimonate.

  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-benzylbenzothiazolium 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 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 Corporation ) 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.), Viscoat 260, 312 and 335HP (above, Osaka Organic Chemical Industries, 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, and as commercially available products thereof, for example, Aronix M-309, M-400, M-405, M-450, M-7100, M-8030, M-8060 (above, manufactured by Toagosei Co., Ltd.), KAYARAD TMPTA, DPHA, DPCA-20, DPCA-30, DPCA-60, DPCA-120 (Nippon Kayaku Co., Ltd.), screw Over DOO 295, the 300, the 360, the GPT, said 3PA, the 400 (manufactured by Osaka Organic Chemical Industry Ltd.) and the like.
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. The proportion of the component [D] used is preferably 50 parts by weight or less, more preferably 30 parts by weight or less with respect to 100 parts by weight of the copolymer [A].
By including the component [D] at such a ratio, the heat resistance and surface hardness of the interlayer insulating film or microlens obtained from the radiation-sensitive resin composition in 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 [E] component (hereinafter sometimes referred to as “E component”) is not limited as long as the compatibility is not affected. Preferably, bisphenol A type epoxy resin, phenol novolak type epoxy resin, cresol novolak type epoxy resin, cyclic aliphatic epoxy resin, glycidyl ester type epoxy resin, glycidyl amine type epoxy resin, heterocyclic epoxy resin, glycidyl methacrylate ) Polymerized resin and the like. Of these, bisphenol A type epoxy resins, cresol novolac type epoxy resins, glycidyl ester type epoxy resins and the like are particularly 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 the component [E] at such a ratio, the heat resistance and surface hardness of the protective film or insulating film obtained from the radiation-sensitive resin composition in 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 differs from the component [E] in that it has alkali solubility. [E] component is alkali-insoluble.
In the radiation sensitive resin composition in the present invention, a surfactant which is the above-mentioned [F] component can be used in order to further improve the coating property. As the [F] surfactant that can be used here, fluorine-based surfactants, silicone-based surfactants, and nonionic surfactants 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 sulfonates; fluoroalkyloxyethylene ethers; fluoroalkylammonium iodides, fluoroalkylpolyoxyethylene ethers, perfluoroalkylpolyoxyethanols; perfluoroalkylalkoxylates; fluorinated alkyl esters be able to. These commercial 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 Polyoxyethylene aryl ethers such as polyoxyethylene dilaurate, polyoxyethylene dialkyl esters such as polyoxyethylene distearate, etc .; (meth) acrylic acid copolymer polyflow Nos. 57 and 95 (Kyoeisha Chemical Co., Ltd.) ))) 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 amount of the surfactant used exceeds 5 parts by weight, the coating film may be easily formed when the coating film is formed on the substrate.

The radiation-sensitive resin composition of the present invention, can also be used an adhesion aid is [G] component in order to improve the adhesion to the substrate. As such [G] adhesion assistant, a functional silane coupling agent is preferably used, and 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. . Specifically, 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 of the radiation-sensitive resin composition The present invention is prepared by uniformly mixing other components to be added above the copolymer [A] and [B] component and optionally such of the Is done. Usually, the radiation sensitive resin composition in 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 copolymer [A] and [B] components and other optionally added components in a predetermined ratio.

As a solvent used for the preparation of the radiation sensitive resin composition in 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 copolymer [A] mentioned above can be mentioned.

  Among such solvents, alcohol, glycol ether, ethylene glycol alkyl ether acetate, ester 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. . Among these, 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, Purpylene 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 for the radiation sensitive resin composition in the present invention, the amount used is 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. can do. If the amount of the high-boiling solvent used exceeds this amount, the coating film thickness uniformity, sensitivity, and residual film rate may decrease.

When the radiation-sensitive resin composition in the present invention is prepared in a solution state, the components other than the solvent in the solution (that is, the total of the copolymer [A] and [B] components and other components optionally added) The ratio of (amount) can be arbitrarily set according to the purpose of use, the value of the desired film thickness, etc., but is preferably 5 to 50% by weight, more preferably 10 to 40% by weight, and still more preferably 15 to 35% by weight.
The composition solution thus prepared can be used after being filtered using a Millipore filter having a pore size of about 0.2 μm.

An interlayer insulating film, using a radiation-sensitive resin composition of the present invention will now form the micro lenses, an interlayer insulating film of the present invention, describes a method of forming a microlens. The method for forming an interlayer insulating film or microlens of the present invention includes the following steps in the order described below.
(1) The process of forming the coating film of the radiation sensitive composition in 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 radiation-sensitive composition on a substrate in the present invention In the step (1), the composition solution in the present invention is applied to the substrate surface, preferably by pre-baking. The solvent is removed to 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 method of applying the composition solution is not particularly limited, and 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 method, or the like is employed. In particular, spin coating and slit die coating are preferred. Prebaking conditions vary depending on the type of each component, the proportion of use, 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 developer is irradiated with radiation through a mask having a predetermined pattern on the formed coating film. The patterning is performed by removing the irradiated portion using the development process. 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 containing g-line and / or i-line is particularly preferable.
The exposure amount, 50~1,500J / ^{m 2} In the case of forming an interlayer insulating film, in the case of forming a micro-lens is preferably set to 50~2,000J / ^{m 2.}

(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, for example, 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-quinonediadito 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 an 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 baking temperature in this hardening process is 120-250 degreeC, for example. Although heating time changes with kinds of heating apparatus, for example, when performing heat processing on a hotplate, it can be set to 30 to 90 minutes when performing heat processing in oven, for example. 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 the 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.

Synthesis example of copolymer [A] Synthesis example 1
A flask equipped with a condenser and a stirrer was charged with 7 parts by weight of 2,2′-azobis (2,4-dimethylvaleronitrile) and 200 parts by weight of diethylene glycol ethyl methyl ether. Subsequently, 14 parts by weight of methacrylic acid, 16 parts by weight of tricyclo [5.2.1.0 ^2,6 ] decan-8-yl methacrylate, 20 parts by weight of 2-methylcyclohexyl acrylate, 40 parts by weight of glycidyl methacrylate, N- (3 , 5-dimethyl-4-hydroxybenzyl) methacrylamide and 3 parts by weight of α-methylstyrene dimer were charged and purged with nitrogen, and then gently stirred. The temperature of the solution was raised to 70 ° C., and this 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. The solid content concentration of the polymer solution obtained here was 34.4% by weight.

Synthesis example 2
A flask equipped with a condenser and a stirrer was charged with 9 parts by weight of 2,2′-azobis (2,4-dimethylvaleronitrile) and 220 parts by weight of diethylene glycol ethyl methyl ether. Subsequently, 12 parts by weight of methacrylic acid, 12 parts by weight of p-methoxystyrene, 15 parts by weight of 1- (tetrahydropyran-2-oxy) -butyl-3-en-2-one, 40 parts by weight of glycidyl methacrylate, N-cyclohexylmaleimide After 10 parts by weight, 10 parts by weight of N- (3,5-dimethyl-4-hydroxybenzyl) methacrylamide and 3 parts by weight of α-methylstyrene dimer were charged and purged with nitrogen, stirring was started gently. The temperature of the solution was raised to 70 ° C., and this temperature was maintained for 4 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 8,100 and a molecular weight distribution (Mw / Mn) of 2.4. The solid content concentration of the polymer solution obtained here was 32.7% by weight.

Synthesis example 3
A flask equipped with a condenser and a stirrer was charged with 7 parts by weight of 2,2′-azobis (2,4-dimethylvaleronitrile) and 220 parts by weight of diethylene glycol ethyl methyl ether. Subsequently, 6 parts by weight of styrene, 16 parts by weight of methacrylic acid, 18 parts by weight of tricyclo [5.2.1.0 ^2,6 ] decan-8-yl methacrylate, 10 parts by weight of N-phenylmaleimide, 40 parts by weight of glycidyl methacrylate, After 10 parts by weight of N- (4-hydroxyphenyl) methacrylamide and 3 parts by weight of α-methylstyrene dimer were charged and purged with nitrogen, stirring was started gently. The temperature of the solution was raised to 70 ° C., and this temperature was maintained for 4.5 hours to obtain a polymer solution containing the copolymer [A-3].
The copolymer [A-3] had a polystyrene equivalent weight average molecular weight (Mw) of 8,500 and a molecular weight distribution (Mw / Mn) of 2.2. Moreover, the solid content concentration of the polymer solution obtained here was 32.2% by weight.

Synthesis example 4
A flask equipped with a condenser and a stirrer was charged with 8.5 parts by weight of 2,2′-azobis (2,4-dimethylvaleronitrile) and 220 parts by weight of diethylene glycol ethyl methyl ether. Subsequently, 15 parts by weight of methacrylic acid, 15 parts by weight of tricyclo [5.2.1.0 ^2,6 ] decan-8-yl methacrylate, 40 parts by weight of glycidyl methacrylate, 10 parts by weight of 3-methacryloyloxytetrahydrofuran-2-one, After 10 parts by weight of n-lauryl methacrylate, 10 parts by weight of N- (4-hydroxyphenyl) methacrylamide and 3 parts by weight of α-methylstyrene dimer were charged and purged with nitrogen, stirring was started gently. The temperature of the solution was raised to 70 ° C., and this temperature was maintained for 4.5 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 7,700 and a molecular weight distribution (Mw / Mn) of 1.8. Moreover, the solid content concentration of the polymer solution obtained here was 31.9% by weight.

Synthesis example 5
A flask equipped with a condenser and a stirrer was charged with 7 parts by weight of 2,2′-azobis (2,4-dimethylvaleronitrile) and 200 parts by weight of diethylene glycol ethyl methyl ether. Subsequently, 10 parts by weight of styrene, 15 parts by weight of methacrylic acid, 40 parts by weight of glycidyl methacrylate, 10 parts by weight of 2-methylcyclohexyl acrylate, 10 parts by weight of 1- (tetrahydropyran-2-oxy) -butyl-3-en-2-one Then, 15 parts by weight of 4-hydroxybenzyl methacrylate and 3 parts by weight of α-methylstyrene dimer were charged and purged with nitrogen, and then gently stirred. The temperature of the solution was raised to 70 ° C., and this temperature was maintained for 4 hours to obtain a polymer solution containing the copolymer [A-5].
The copolymer [A-5] had a polystyrene equivalent weight average molecular weight (Mw) of 8,300 and a molecular weight distribution (Mw / Mn) of 2.1. The polymer solution obtained here had a solid content concentration of 33.9% by weight.

Synthesis Example 6
A flask equipped with a condenser and a stirrer was charged with 8 parts by weight of 2,2′-azobis (2,4-dimethylvaleronitrile) and 200 parts by weight of diethylene glycol ethyl methyl ether. Subsequently, 10 parts by weight of p-hydroxystyrene, 15 parts by weight of methacrylic acid, 20 parts by weight of tricyclo [5.2.1.0 ^2,6 ] decan-8-yl methacrylate, 40 parts by weight of glycidyl methacrylate, and 4-hydroxybenzyl methacrylate. After 15 parts by weight and 3 parts by weight of α-methylstyrene dimer were charged and purged with nitrogen, stirring was started gently. The temperature of the solution was raised to 70 ° C., and this temperature was maintained for 4.5 hours to obtain a polymer solution containing the copolymer [A-6].
The copolymer [A-6] had a polystyrene equivalent weight average molecular weight (Mw) of 7,600 and a molecular weight distribution (Mw / Mn) of 2.0. The solid content concentration of the polymer solution obtained here was 34.5% by weight.

Synthesis example 7
A flask equipped with a condenser and a stirrer was charged with 7.5 parts by weight of 2,2′-azobis (2,4-dimethylvaleronitrile) and 230 parts by weight of diethylene glycol ethyl methyl ether. Subsequently, 5 parts by weight of styrene, 15 parts by weight of methacrylic acid, 5 parts by weight of tricyclo [5.2.1.0 ^2,6 ] decan-8-yl methacrylate, 40 parts by weight of glycidyl methacrylate, and 15 parts by weight of p-vinylbenzylglycidyl ether. Parts, 10 parts by weight of tetrahydrofurfuryl methacrylate, 10 parts by weight of 4-hydroxyphenyl methacrylate, and 3 parts by weight of α-methylstyrene dimer were charged with nitrogen, and then gently stirred. 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-7].
The copolymer [A-7] had a polystyrene equivalent weight average molecular weight (Mw) of 8,500 and a molecular weight distribution (Mw / Mn) of 2.3. The polymer solution thus obtained had a solid content concentration of 32.8% by weight.

Synthesis example 8
A flask equipped with a condenser and a stirrer was charged with 7 parts by weight of 2,2′-azobis (2,4-dimethylvaleronitrile) and 200 parts by weight of diethylene glycol ethyl methyl ether. Subsequently, 12 parts by weight of methacrylic acid, 40 parts by weight of glycidyl methacrylate, 23 parts of tetrahydrofurfuryl methacrylate, 5 parts by weight of 3-methacryloyloxytetrahydrofuran-2-one, 10 parts by weight of N-cyclohexylmaleimide, 10 parts by weight of 4-hydroxyphenyl methacrylate , And 3 parts by weight of α-methylstyrene dimer were charged and purged with nitrogen, and then gently stirred. 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-8].
The copolymer [A-8] had a polystyrene equivalent weight average molecular weight (Mw) of 8,000 and a molecular weight distribution (Mw / Mn) of 2.2. The polymer solution obtained here had a solid content concentration of 32.4% by weight.

Synthesis Example 9
A flask equipped with a condenser and a stirrer was charged with 8.5 parts by weight of 2,2′-azobis (2,4-dimethylvaleronitrile) and 220 parts by weight of diethylene glycol ethyl methyl ether. Subsequently, 10 parts by weight of methacrylic acid, 40 parts by weight of glycidyl methacrylate, 25 parts of tetrahydrofurfuryl methacrylate, 15 parts by weight of N-phenylmaleimide, 10 parts by weight of α-methyl-p-hydroxystyrene, and 3 parts by weight of α-methylstyrene dimer Was added, and the mixture was purged with nitrogen. 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-9].
The copolymer [A-9] had a polystyrene equivalent weight average molecular weight (Mw) of 7,900 and a molecular weight distribution (Mw / Mn) of 2.3. The solid content concentration of the polymer solution obtained here was 32.0% by weight.

Synthesis Example 10
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, 13 parts by weight of methacrylic acid, 12 parts by weight of tricyclo [5.2.1.0 ^2,6 ] decan-8-yl methacrylate, 40 parts by weight of glycidyl methacrylate, 15 parts of N-cyclohexylmaleimide, 10 parts by weight of lauryl methacrylate, After 10 parts by weight of α-methyl-p-hydroxystyrene and 3 parts by weight of α-methylstyrene dimer were charged and purged with nitrogen, stirring was started gently. 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-10].
The copolymer [A-10] had a polystyrene equivalent weight average molecular weight (Mw) of 8,000 and a molecular weight distribution (Mw / Mn) of 2.3. Moreover, the solid content concentration of the polymer solution obtained here was 31.9% 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. Moreover, the solid content concentration of the polymer solution obtained here was 30.6% by weight.

Example 1
[Preparation of radiation-sensitive resin composition]
The solution containing the polymer [A-1] as the [A] component synthesized in Synthesis Example 1 above, as the amount corresponding to 100 parts by weight (solid content) of the polymer [A-1], and the component [B] 4,4 ′-[1- [4- [1- [4-Hydroxyphenyl] -1-methylethyl] phenyl] ethylidene] bisphenol (1.0 mol) and 1,2-naphthoquinonediazide-5-sulfonic acid chloride (2.0 mol) of a condensate (B-1) (30 parts by weight) was mixed and dissolved in diethylene glycol ethyl methyl ether so that the solid content concentration was 30% by weight, and then a membrane filter having a diameter of 0.2 μm. The solution (S-1) of the radiation sensitive resin composition was prepared by filtration.

Examples 2-36, Comparative Examples 1-4
[Preparation of radiation-sensitive resin composition]
In Example 1, a solution of the radiation-sensitive resin composition was carried out in the same manner as in Example 1 except that the types and amounts shown in Table 1 were used as the [A] component and the [B] component. (S-2) to (S-36) and (s-1) to (s-4) were prepared.
In Example 8, the description of the component [B] represents that two types of 1,2-quinonediazide compounds were used in combination.

Example 37
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 a radiation sensitive resin composition (S-37) Was prepared.

Example 38
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 / propylene glycol monomethyl ether acetate = 6/4 so that the solid content concentration was 20% by weight. A resin composition solution (S-38) 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)
(F): SH-28PA (Toray Dow Corning Silicone Co., Ltd.)

Examples 38-77, Comparative Examples 5-10
<Performance evaluation as interlayer insulation 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]
On the silicon substrate, after apply | coating the composition of Table 2 using a spin die for Examples 38-75 and Comparative Examples 5-10, and using a slit die coater about Examples 76-77, 90 A film having a thickness of 3.0 μm was formed by prebaking on a hot plate at 2 ° C. for 2 minutes. The obtained coating film was exposed through a pattern mask having a predetermined pattern with a PLA-501F exposure machine (extra-high pressure mercury lamp) manufactured by Canon Inc., and the exposure time was changed. When using a developer solution with a concentration of tetramethylammonium hydroxide at 25 ° C., 0.4%, and 0.5%, 80 seconds when using a developer solution with a concentration of 2.38%, 80 seconds. Developed for 2 seconds by the liquid piling method. 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 1000 J / m ² or less.

[Evaluation of development margin]
On the silicon substrate, after apply | coating the composition of Table 2 using a spin die for Examples 38-75 and Comparative Examples 5-10, and using a slit die coater about Examples 76-77, 90 A film having a thickness of 3.0 μm was formed by prebaking on a hot plate at 2 ° C. for 2 minutes. 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 to 1) pattern on the obtained coating film, Exposure is carried out with an exposure amount corresponding to the sensitivity value measured in [Evaluation of Sensitivity], and a liquid piling method is performed by changing the development time with an aqueous tetramethylammonium hydroxide solution having the concentration shown in Table 2 at 25 ° C. Developed with. 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]
On the silicon substrate, after apply | coating the composition of Table 2 using a spin die for Examples 38-75 and Comparative Examples 5-10, and using a slit die coater about Examples 76-77, 90 A film having a thickness of 3.0 μm was formed by prebaking on a hot plate at 2 ° C. for 2 minutes. 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 film 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 the 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]
On the polished SUS304 substrate, the compositions described in Table 2 were applied using a spinner for Examples 38 to 75 and Comparative Examples 5 to 10 and using a slit die coater for Examples 76 to 77. 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 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 dielectric constant is good.
In the evaluation of the 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.

Examples 78-115, Comparative Examples 11-16
<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 of 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]
For Examples 78 to 115 and Comparative Examples 11 to 16 on a silicon substrate, the compositions shown in Table 3 were applied using a spinner, and then prebaked on a hot plate at 90 ° C. for 2 minutes. A 2.0 μm coating film was formed. 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, and exposure was performed in Table 3. Development was carried out by a puddle method at 25 ° C. for 1 minute in an aqueous tetramethylammonium hydroxide solution having the 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 (one to one) 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 2,000 J / m ² or less.

[Evaluation of development margin]
For Examples 78 to 115 and Comparative Examples 11 to 16 on a silicon substrate, the compositions shown in Table 3 were applied using a spinner, and then prebaked on a hot plate at 90 ° C. for 2 minutes. A 2.0 μm coating film was formed. The obtained coating film was measured by the above-mentioned “[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. Exposure was carried out with an exposure amount corresponding to the sensitivity value, and development was carried out with a tetramethylammonium hydroxide aqueous solution having a concentration shown in Table 3 at 25 ° C. for 1 minute. It was rinsed with water and dried to form a pattern on the wafer. Table 3 shows the development time required 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]
For Examples 78 to 115 and Comparative Examples 11 to 16 on a silicon substrate, the compositions shown in Table 3 were applied using a spinner, and then prebaked on a hot plate at 90 ° C. for 2 minutes. A 2.0 μm coating film was formed. 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]
For Examples 78 to 115 and Comparative Examples 11 to 16 on a silicon substrate, the composition described in Table 3 was applied using a spinner, and then prebaked on a hot plate at 90 ° C. for 2 minutes to obtain a film thickness of 2 A coating film of 0.0 μm was formed. The obtained coating film was passed through a pattern mask having 4.0 [mu] m dots and 2.0 [mu] m space pattern with the NSR1755i7A reduction projection exposure machine (NA = 0.50, [lambda] = 365 nm) manufactured by Nikon Corporation. Exposure is performed with an exposure amount corresponding to the sensitivity value measured in [Evaluation of Sensitivity], and 25 ° C. is applied in a tetramethylammonium hydroxide aqueous solution having a concentration described as the developer concentration in the sensitivity evaluation in Table 3. Development was carried out by a puddle method for 1 minute. It was rinsed with water and dried to form a pattern on the wafer. Then, it exposed so that an 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).

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

Claims (4)

A method for forming an interlayer insulating film, comprising the following steps in the order described below.
(1) [A] (a1) unsaturated carboxylic acid and / or unsaturated carboxylic acid anhydride,
(A2) an epoxy group-containing unsaturated compound,
(A3) Formula (I) below

Here, R ¹ is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, R ^{2 to} R ⁶ are the same or different, and are a hydrogen atom, a hydroxyl group or an alkyl group having 1 to 4 carbon atoms, and B is a single atom. A bond, —COO—, or —CONH—, and m is an integer of 0 to 3, provided that at least one of R ^{2 to} R ⁶ is a hydroxyl group.
A phenol skeleton-containing unsaturated compound represented by:
(A4) a copolymer of unsaturated compounds other than (a1), (a2) and (a3), and
[B] 1,2-quinonediazide compound
A step of forming a coating film of a radiation-sensitive composition containing
(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 1 . A method for forming a microlens comprising the following steps in the order described below.
(1) [A] (a1) unsaturated carboxylic acid and / or unsaturated carboxylic acid anhydride,
(A2) an epoxy group-containing unsaturated compound,
(A3) a phenol skeleton-containing unsaturated compound represented by the above formula (I), and
(A4) a copolymer of unsaturated compounds other than (a1), (a2) and (a3), and
[B] 1,2-quinonediazide compound
A step of forming a coating film of a radiation-sensitive composition containing
(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 3 .

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