JP2001255651A - Heat resistant photosensitive resin composition, method for producing pattern and electronic parts - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat resistant photosensitive resin composition having high sensitivity and superior photosensitive characteristics and giving a good pattern excellent in shape even with low light exposure, to provide a method for producing a pattern by which high sensitivity and superior photosensitive characteristics are ensured and to provide a good pattern excellent in shape is obtained even with low light exposure and electronic parts excellent in reliability by having the pattern. SOLUTION: The heat resistant photosensitive resin composition contains a bissulfonium borate compound and a heat resistant resin. The method for producing a pattern includes a step for forming a film using the photosensitive resin composition, a step for irradiating the film with light through a mask having a prescribed pattern and a step for developing the irradiated film with an organic solvent or a basic aqueous solution. Each of the electronic parts has a pattern obtained by the above method.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat-resistant photosensitive resin composition useful as a surface protective film or an interlayer insulating film of a semiconductor device, an insulating film of a multilayer wiring board, and a method for producing a pattern using the same. And electronic components.

[0002]

2. Description of the Related Art Photosensitive resin compositions have been used in a wide range of industrial fields such as UV inks, printing plates, holograms using lasers, dry films, and resists for fine processing of semiconductors. These photosensitive resin compositions are generally formed from a resin, a crosslinking agent, and a photopolymerization initiator. Accordingly, the physical properties of the cured film of the photosensitive resin composition are determined by the resin, and the photoimage forming ability is determined by the crosslinking agent and the photopolymerization initiator. That is, it is necessary to select an appropriate photopolymerization initiator depending on the light source used for molding, the resin structure, the type of the crosslinking agent, and other conditions used.

For example, for processing a heat-resistant material such as a photosensitive polyimide precursor as a semiconductor protective film, a reduction projection exposure machine called a stepper used in a semiconductor production line is used. Until now, the stepper has been used as a visible light (wavelength: 435 nm) called g-line of an ultra-high pressure mercury lamp.
Although the g-line stepper using the i-line is the mainstream, it is shifting to the i-line stepper (wavelength: 365 nm) in order to further meet the demand for finer processing rules.

[0004] However, these photosensitive polyimide precursors use a basic skeleton as an aromatic monomer having excellent heat resistance and mechanical properties. Due to the absorption of the polyimide precursor itself, its light transmittance in the ultraviolet region is low. Low, i-line (wavelength: 36
5 nm) is very low. Therefore, there was a problem that the photochemical reaction in the exposed portion could not be sufficiently performed, resulting in low sensitivity and deterioration of the pattern shape.

[0005] Furthermore, since a polyimide film for surface protection is required to be thicker in response to LOC (lead-on-chip), which is a high-density mounting method for semiconductor elements, the transmittance becomes worse toward the bottom. And the problem gets worse. Therefore, there is a strong demand for a photosensitive resin composition which has sufficient sensitivity even at the bottom where the illuminance by the i-line stepper is extremely low and which can obtain a good pattern shape.

[0006] Oxime ester compounds such as 1-phenyl-1,2-propanedione-2- (o-ethoxycarbonyl) oxime, and 2,2,2 are highly sensitive photoinitiators for such photosensitive resin compositions. '-Bis (2-chlorophenyl) -4,4', 5,5'-tetraphenylbiimidazole (o-Cl-HABI) has been used. However, oxime ester compounds generally have insufficient thermal stability, and o-Cl-HABI has a problem of liberation of Cl ions in a semiconductor process. Furthermore, both initiators were insufficient at present in terms of sensitivity. In addition, borate compounds such as tetraethylammonium tetraphenylborate and onium salts such as diphenyliodonium triflate are also known as initiators, but have low sensitivity at i-line, and compounds when compounded in a photosensitive resin composition. It was not satisfactory as an initiator due to lack of stability.

[0007]

SUMMARY OF THE INVENTION The present invention provides a heat-resistant photosensitive resin composition which has higher sensitivity than conventional ones, has excellent photosensitive characteristics, and can obtain a good pattern having an excellent shape even at a low exposure dose. It provides things. Another object of the present invention is to provide a method for producing a pattern which has higher sensitivity than conventional ones, has excellent photosensitive characteristics, and can obtain a good pattern having an excellent shape even at a low exposure dose. Further, the present invention provides an electronic component having excellent reliability by having the pattern.

[0008]

The present invention relates to a heat-resistant photosensitive resin composition containing a bissulfonium borate compound and a heat-resistant resin. In the present invention, the bissulfonium borate compound may be a compound represented by the general formula (I):

Embedded image (In the formula, each X is independently an alkyl group having 1 to 12 carbon atoms, the alkyl group substituted with a hydroxyl group or a halogen atom, and R ¹ , R ² , R ³ and R ⁴ are each independently Which is an alkyl group having 1 to 12 carbon atoms, a phenyl group, a benzyl group, a substituted phenyl group or a substituted benzyl group).

In the present invention, the bissulfonium borate compound preferably has the general formula (II):

Embedded image A heat-resistant photosensitive resin composition which is a compound represented by the formula:

In the present invention, the bissulfonium borate compound preferably has the general formula (III):

Embedded image A heat-resistant photosensitive resin composition which is a compound represented by the formula:

The present invention also relates to a heat-resistant photosensitive resin composition wherein the heat-resistant resin is a polyimide precursor. The present invention also relates to a heat-resistant photosensitive resin composition wherein the polyimide precursor has a carbon-carbon unsaturated double bond.

The present invention also provides a step of forming a film using the heat-resistant photosensitive resin composition according to any of the above, a step of irradiating the film with light through a mask having a predetermined pattern, The present invention relates to a method for producing a pattern including a step of developing a film after light irradiation using an organic solvent or a basic aqueous solution. Furthermore, the present invention relates to an electronic component having, as a film, a pattern obtained by the above-mentioned manufacturing method.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, a bissulfonium borate compound is used as a photopolymerization initiator. This is obtained by combining a conventionally known onium cation and borate anion. As the bissulfonium borate compound, the bissulfonium borate compound represented by the general formula (I) is preferred because of its high sensitivity, and among them, the compounds represented by the general formulas (II) and (III) are particularly preferable. Preferred are given.

Each X in the bissulfonium borate compound represented by the general formula (I) is independently
The alkyl group having 1 to 12 carbon atoms, the alkyl group substituted with a hydroxyl group, a halogen atom such as a fluorine atom, a chlorine atom, and a bromine atom. R ¹ , R ² , R ³ , and R ⁴ are each independently an alkyl group having 1 to 12 carbon atoms, a phenyl group, a benzyl group, a substituted phenyl group, or a substituted benzyl group. Examples of the alkyl group include a linear or branched alkyl group having 1 to 12 carbon atoms, and more specifically, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, and a t- Examples thereof include a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, an unenyl group, and a doenyl group. The substituted phenyl group and the substituted benzyl group may be a linear or branched alkyl group having 1 to 6 carbon atoms or a linear chain having 1 to 6 carbon atoms at any one or more positions on the phenyl ring of these substituents. Substituted by a linear or branched alkyloxy group, a linear or branched alkylamino group having 1 to 6 carbon atoms, a nitro group, a hydroxy group, an amino group, a fluorine atom, a chlorine atom or a bromine atom, etc. Is mentioned.

The method for producing the bissulfonium borate compound is not particularly limited. For example, under an acidic condition (for example, in the presence of methanesulfonic acid using phosphorus pentoxide as a catalyst), 2 equivalents of diaryl sulfoxide and 1 equivalent of diphenyl sulfide are used. Is reacted, and an aqueous solution of a sodium salt of a tetraaryl borate corresponding to the solution is added dropwise. According to this method, one-pot synthesis is also possible.

In the present invention, a heat-resistant resin is used. As the heat-resistant resin, generally, the thermal decomposition temperature is 300.
C. or higher, and specific types of resin include polyimide, polyimide precursor (polyamic acid, polyamic acid ester, polyamic acid amide, etc.), polyoxazole, polyoxazole precursor (polyhydroxyamide) , Polyamide, polyamide imide, etc., and are preferably polyimide precursors which exhibit good characteristics as a protective film or an insulating film of a semiconductor device.

Among them, it is preferable to use a polyimide precursor having a photopolymerizable carbon-carbon double bond and exhibiting good photosensitivity. As the polyimide precursor having a photopolymerizable carbon-carbon double bond, a polyamic acid unsaturated ester having a structure in which a compound having a photopolymerizable carbon-carbon double bond is covalently bonded to a side chain of polyamic acid or Polyamide acid unsaturated amides, polyamic acid mixed with an amine compound having a carbon-carbon double bond, and an ion-bonding polyimide precursor obtained by introducing a carbon-carbon double bond through an ionic bond between a carboxyl group and an amino group. No. The carbon-carbon unsaturated double bond is preferably contained in the form of an acryloyl group or a methacryloyl group.

Among these, a polyamic acid having a repeating unit represented by the following general formula (IV) can be used in combination with the bissulfonium borate compound used in the present invention because excellent sensitivity and shortening of development time can be achieved. Unsaturated esters are preferred.

Embedded image (Wherein, R ⁵ is a tetravalent organic group, R ⁶ is a divalent, trivalent, or
R ⁷ is a monovalent organic group having a carbon-carbon double bond, A is an acidic monovalent group, n is 0, 1 or 2
Is)

In the repeating unit represented by the general formula (IV), the tetravalent organic group represented by R ⁵ is usually a tetracarboxylic acid or a derivative thereof which can react with a diamine to form a polyimide precursor. It is a residue, and is preferably a tetravalent organic group having 4 or more carbon atoms from the viewpoints of mechanical properties, heat resistance, and adhesiveness of the polyimide film obtained by curing. Among tetravalent organic groups having 4 or more carbon atoms, the total number of carbon atoms including aromatic rings (benzene ring, naphthalene ring, etc.) is 6 to 3;
More preferably, it is 0. Further, it is preferable that the binding sites of the four carboxyl groups of the tetracarboxylic acid are two pairs of two binding sites existing at the ortho position or the peri position of the aromatic ring. In a plurality of the repeating units in one molecule of the polyamic acid ester, all R4s may be the same or different.

In the general formula (IV), those wherein n is 1 or 2 are preferred in that they have excellent solubility in a basic aqueous solution. Examples of the acidic group represented by A include a sulfonic acid group (—SO ₃ H), a sulfinic acid group (—SO ₂ H),
It is preferable to use any of a carboxyl group (—COOH) and a phenolic hydroxyl group because of good solubility, and the carboxyl group and the phenolic hydroxyl group are more preferable because the synthesis of the polyimide precursor is easy, and a carboxyl group is particularly preferable. In a plurality of the repeating units in one molecule of the polyamic acid ester, all A may be the same or different. Further, when n is 0, in order to impart solubility to a basic aqueous solution, in addition to the repeating unit of the general formula (IV), R ⁷ of the repeating unit represented by the general formula (IV) is It is preferable to have a unit of a hydrogen atom, that is, a partial ester of polyamic acid.

In the general formula (IV), the group R ⁶ to which the acidic group A is bonded is usually a diamine residue capable of forming a polyimide precursor by reacting with tetracarboxylic acid or a derivative thereof. From the viewpoint of the mechanical properties, heat resistance and adhesiveness of the polyimide film obtained by the above, it is preferable that the polyimide is an organic group containing an aromatic ring, and the mechanical properties, heat resistance and adhesiveness of the polyimide film obtained by curing. Therefore, it is more preferable that the organic group is an organic group containing an aromatic ring and having 6 to 30 carbon atoms in total. Note that, in the plurality of repeating units in the polyimide precursor molecule, all R ⁷ may be the same or different.

In the general formula (IV), the group having a carbon-carbon double bond represented by R ⁷ includes the following general formula (V)

Embedded image (However, R ⁸ , R ⁹ and R ¹⁰ are each independently a group selected from hydrogen, an alkyl group, a phenyl group, a vinyl group and a propenyl group, and R ¹¹ represents a divalent organic group) The organic group represented is preferable because it can impart high sensitivity photosensitivity. Examples of the alkyl group include those having 1 to 4 carbon atoms. Examples of the divalent organic group represented by R ¹¹ include an alkylene group having 1 to 20 carbon atoms such as a methylene group, an ethylene group, and a propylene group.

Of these, methacryloyloxyalkyl groups and acryloyloxyalkyl groups (having 1 to 20 carbon atoms in the alkyl group) not only realize high sensitivity, but also are easy to synthesize, and thus are suitable for the present invention. It is. The polyamic acid ester may include a repeating unit other than the repeating unit represented by the general formula (IV).

In the polyimide precursor of the present invention, when n is 1 or 2, the proportion of the repeating unit represented by the general formula (IV) is 10 to 100 mol% in terms of mol percentage in all the repeating units. It is preferable that the content is excellent because the balance between the developability in a basic aqueous solution and the good pattern shape is excellent, and the content is more preferably 80 to 100 mol%. This adjustment can be made according to the types and amounts of the tetracarboxylic dianhydride, diamine, and carbon-carbon double bond-containing compound used as the material.

When n is 0, the general formula (IV)
The ratio of the repeating unit represented by
Molar% is preferred because of excellent pattern shape, and more preferably 30 to 100 mole%. In order to provide developability in a basic aqueous solution, it is preferable that the repeating unit of another unit, for example, an ester of polyamic acid or one of its carboxyl groups is 15 to 50 mol%.

The polyamic acid ester is mixed with a tetracarboxylic dianhydride and a hydroxy group-containing compound having an unsaturated group and reacted to produce a half ester of tetracarboxylic acid, which is then acid chlorided with thionyl chloride. Then, it can be synthesized by a method of reacting with a diamine, an acid chloride method of reacting the tetracarboxylic acid half ester with a diamine using a carbodiimide as a condensing agent, a method of using a carbodiimide condensing agent, an isoimide method, or the like.

The tetracarboxylic dianhydride includes:
For example, oxydiphthalic acid, pyromellitic acid, 3,
3 ', 4,4'-benzophenonetetracarboxylic acid,
3,3 ', 4,4'-biphenyltetracarboxylic acid,
1,2,5,6-naphthalenetetracarboxylic acid, 2,
3,6,7-naphthalenetetracarboxylic acid, 1,4
5,8-naphthalenetetracarboxylic acid, 2,3,5,6
-Pyridinetetracarboxylic acid, 3,4,9,10-perylenetetracarboxylic acid, sulfonyldiphthalic acid, m-terphenyl-3,3 ', 4,4'-tetracarboxylic acid,
p-terphenyl-3,3 ', 4,4'-tetracarboxylic acid, 1,1,1,3,3,3-hexafluoro-2,
2-bis (2,3- or 3,4-dicarboxyphenyl) propane, 2,2-bis (2,3- or 3,4-dicarboxyphenyl) propane, 2,2-bis {4'-
(2,3- or 3,4-dicarboxyphenoxy) phenyl} propane, 1,1,1,3,3,3-hexafluoro-2,2-bis {4 ′-(2,3- or 3, 4-dicarboxyphenoxy) phenyl} propane having the following general formula (VI)

Embedded image (Wherein, R ¹² and R ¹³ each independently represent a monovalent hydrocarbon group (preferably an alkyl group having 1 to 10 carbon atoms or a phenyl group), and s is 1 or more (preferably 1 to 30) And dianhydrides of aromatic tetracarboxylic acids such as tetracarboxylic acids represented by the following formulas. These are used alone or in combination of two or more.

The diamine which gives a diamine residue (R ^6- (A) _n ) in the repeating unit represented by the general formula (IV) in which n is 1 or 2 is 3,5-diaminobenzoic acid 4,4'-dihydroxy-3,3'-diaminobiphenyl, 3,4-diaminobenzoic acid, 3,3 '
-Dihydroxy-4,4'-diaminobiphenyl, 2,
3-diamino-4-hydroxypyridine, 2,2-bis (4-hydroxy-3-aminophenyl) hexafluoropropane, 2,4-diaminophenol, 2,4-diaminobenzoic acid, 3-carboxy-4,4 '-Diaminodiphenyl ether, 3,3'-dicarboxy-4,
4'-diaminodiphenyl ether, 3-carboxy-
4,4'-diaminodiphenylmethane, 3,3'-dicarboxy-4,4'-diaminodiphenylmethane, 3,
3'-dicarboxy-4,4'-diaminobiphenyl,
3,3 ', 5,5'-tetracarboxy-4,4'-diaminobiphenyl, 3-carboxy-4,4'-diaminodiphenylsulfone, 3,3'-dicarboxy-4,
4'-diaminodiphenyl sulfone, 1,1,1,3,
3,3-hexafluoro-2,2-bis (3-carboxy-4-aminophenyl) propane and the like.

In the repeating unit represented by the general formula (IV), the diamine providing a diamine residue in which n is 0 is 4,4'- (or 3,4'-, 3,3'-, 2,
4 '-, 2,2'-) diaminodiphenyl ether,
4,4'- (or 3,4'-, 3,3'-, 2,4 '
-, 2,2 '-) diaminodiphenylmethane, 4,4'
-(Or 3,4'-, 3,3'-, 2,4'-, 2,
2'-) diaminodiphenyl sulfone, 4,4'- (or 3,4'-, 3,3'-, 2,4'-, 2,2'-)
Diaminodiphenyl sulfide, paraphenylenediamine, metaphenylenediamine, p-xylylenediamine, m-xylylenediamine, o-tolidine, o-tolidinesulfone, 4,4'-methylene-bis- (2,6-
Diethylaniline), 4,4'-methylene-bis-
(2,6-diisopropylaniline), 2,4-diaminomesitylene, 1,5-diaminonaphthalene, 4,4 ′
-Benzophenonediamine, bis- {4- (4'-aminophenoxy) phenyl} sulfone, 1,1,1,3,
3,3-hexafluoro-2,2-bis (4-aminophenyl) propane, 2,2-bis {4- (4'-aminophenoxy) phenyl} propane, 3,3'-dimethyl-4,4 ' -Diaminodiphenylmethane, 3,3 ',
5,5'-tetramethyl-4,4'-diaminodiphenylmethane, bis {4- (3'-aminophenoxy) phenyl} sulfone, 2,2-bis (4-aminophenyl)
And propane. These are used alone or in combination of two or more.

In addition, as a diamine residue, the following general formula (VII) is used in order to improve the adhesiveness.

Embedded image (Wherein, R ¹⁴ and R ^{15 each} represent a divalent hydrocarbon group (preferably an alkylene group having 1 to 10 carbon atoms), which may be the same or different, and R ¹⁶ and R ¹⁷ are monovalent A diamine such as diaminopolysiloxane represented by a hydrocarbon group (preferably an alkyl group having 1 to 10 carbon atoms or a phenyl group), which may be the same or different, and t is an integer of 1 or more. Can also be used. As R ¹⁴ and R ¹⁵ , a methylene group, an ethylene group,
R ¹⁶ and R ¹⁶ include alkylene groups such as propylene groups, arylene groups such as phenylene groups, and bonding groups thereof.
^Examples of ¹⁷ include an alkyl group such as a methyl group and an ethyl group, and an aryl group such as a phenyl group. When these are used, it is preferable to use 1 to 30 mol% based on all amine components.

As the diamine, 4,4'-diaminodiphenyl ether-3-sulfonamide, 3,4'-diaminodiphenyl ether-
4-sulfonamide, 3,4'-diaminodiphenylether-3'-sulfonamide, 3,3'-diaminodiphenylether-4-sulfonamide, 4,4'-diaminodiphenylether-3-carboxamide, 3,
Use of a diamine compound having a sulfonamide group or a carboxamide group such as 4'-diaminodiphenyl ether-4-carboxamide, 3,4'-diaminodiphenyl ether-3'-carboxamide, and 3,3'-diaminodiphenyl ether-4-carboxamide. Can also. When these are used, 1 to all amine components
Preferably, it is used in an amount of up to 30 mol%. These diamines are used alone or in combination of two or more.

In the present invention, the polyimide precursor (A)
As the molecular weight of the cured film after imidization,
The weight average molecular weight is preferably from 10,000 to 200,000, more preferably from 20,000 to 80,000.
If the molecular weight is less than 10,000, mechanical strength tends to be poor, and if it exceeds 200,000, developability tends to be poor. The weight average molecular weight can be measured by GPC (gel permeation chromatography) and calculated in terms of polystyrene.

In the heat-resistant photosensitive resin composition of the present invention, the content of the bissulfonium borate compound is as follows:
0.1 to 15 parts by weight, preferably 0.1 to 10 parts by weight, more preferably 0.5 to 10 parts by weight, based on 100 parts by weight of the heat-resistant resin. .

The heat-resistant photosensitive resin composition of the present invention preferably further contains an addition polymerizable compound having a boiling point of 100 ° C. or more at normal pressure, which is added to 100 parts by weight of the heat-resistant resin. It is preferable to use 5 to 50 parts by weight.

Specific examples thereof include compounds obtained by condensing a polyhydric alcohol and an α, β-unsaturated carboxylic acid, for example, ethylene glycol di (meth) acrylate (the meaning of diacrylate or dimethacrylate;
The same applies hereinafter), triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, trimethylolpropane di (meth) acrylate, trimethylolpropane tri (meth) acrylate, 1,2-propylene glycol di (meth) acrylate Acrylate, di (1,2-propylene glycol) di (meth)
Acrylate, tri (1,2-propylene glycol)
Di (meth) acrylate, tetra (1,2-propylene glycol) di (meth) acrylate, dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, dimethylaminopropyl (meth) acrylate, diethylaminopropyl (meth) acrylate , 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, pentaerythritol tri (meth) acrylate, and the like. Further, styrene, divinylbenzene, and 4-vinyltoluene can be used. , 4-vinylpyridine, N
-Vinylpyrrolidone, 2-hydroxyethyl (meth) acrylate, 1,3- (meth) acryloyloxy-2
-Hydroxypropane, methylenebisacrylamide,
N, N-dimethylacrylamide, N-methylolacrylamide, neopentyl glycol di (meth) acrylate, pentaerythritol di (meth) acrylate, dipentaerythritol hexa (meth) acrylate, tetramethylolpropanetetra (meth) acrylate, and the like. . These are used alone or in combination of two or more.

In the present invention, the sensitivity can be further increased by adding a hydrogen donor such as an amine. Particularly preferred compounds as the hydrogen donor include arylglycine compounds and mercapto compounds.

As the arylglycine compound, N-
Phenylglycine (NPG), N- (p-chlorophenyl) glycine, N- (p-bromophenyl) glycine,
N- (p-cyanophenyl) glycine, N- (p-methylphenyl) glycine, N-methyl-N-phenylglycine, N- (p-bromophenyl) -N-methylglycine, N- (p-chlorophenyl) —N-ethylglycine and the like. The content of these is 100
The amount is preferably from 0.1 to 10 parts by weight, more preferably from 0.5 to 6.0 parts by weight, based on parts by weight.

The mercapto compounds include mercaptobenzoxazole, mercaptobenzothiazole, mercaptobenzimidazole, and 2,5-mercapto-
1,3,4-thiadiazole, 1-phenyl-5-mercapto-1H-tetrazole, 5-methyl-1,3,4
-Thiadiazole-2-thiol, 3-mercapto-4
-Methyl-4H-1,2,4-triazole and the like. The content of these is preferably 0.1 to 10 parts by weight with respect to 100 parts by weight of the heat-resistant resin.
More preferably, the content is 5 to 6.0 parts by weight.

The heat-resistant photosensitive resin composition of the present invention may optionally contain a sensitizer. Examples of the sensitizer include 7-N, N-diethylaminocoumarin and 7-N, N-diethylaminocoumarin.
-Diethylamino-3-thenonylcoumarin, 3,3'-
Carbonyl bis (7-N, N-diethylamino) coumarin, 3,3'-carbonylbis (7-N, N-dimethoxy) coumarin, 3-thienylcarbonyl-7-N, N-diethylaminocoumarin, 3-benzoylcoumarin, 3
-Benzoyl-7-N, N-methoxycoumarin, 3-
(4'-methoxybenzoyl) coumarin, 3,3'-carbonylbis-5,7- (dimethoxy) coumarin, benzalacetophenone, 4'-N, N-dimethylaminobenzalacetophenone, 4'-acetoaminobenzal −
4-methoxyacetophenone, dimethylaminobenzophenone, diethylaminobenzophenone (EAB),
4,4'-bis (N-ethyl, N-methyl) benzophenone (MEAB) and the like. These contents are
In general, it is preferably 0.01 to 10 parts by weight based on 100 parts by weight of the heat-resistant resin, although it depends on the molar extinction coefficient at 365 nm and the molecular weight. The photosensitive resin composition of the present invention has other additives, for example, a plasticizer,
An additive such as an adhesion promoter may be contained.

The heat-resistant photosensitive resin composition of the present invention can be generally diluted with an organic solvent to adjust the viscosity. As the organic solvent, for example, acetone, methyl ethyl ketone, diethyl ketone, toluene, chloroform,
Methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, t-butanol, ethylene glycol monomethyl ether, xylene, tetrahydrofuran, dioxane, cyclopentanone, N, N-dimethylacetamide, N, N- Dimethylformamide, N-methyl-2-pyrrolidone, N-acetyl-2-pyrrolidone, N-benzyl-2-pyrrolidone, γ-butyrolactone, dimethylsulfoxide, ethylene carbonate, propylene carbonate, sulfolane, hexamethylenephosphortriamide, N-acetyl-ε- Preferred examples include caprolactam, dimethylimidazolidinone, diethylene glycol dimethyl ether, and triethylene glycol dimethyl ether. These may be used alone or as a mixed system. There is no particular limitation on the amount used,
Generally, it is preferable that the amount is 10 to 90% by weight based on the total amount of the composition.

The photosensitive composition of the present invention may contain other additives, for example, additives such as a plasticizer and an adhesion promoter.

According to the method for producing a pattern of the present invention, a resin film composed of a cured product of the photosensitive resin composition of the present invention is formed by a photolithography technique. The coating made of the heat-resistant photosensitive resin composition is, for example,
After forming a varnish film of the heat-resistant photosensitive resin composition, it is formed by drying. The formation of the varnish film can be performed by a means appropriately selected from means such as spin coating using a spinner, dipping, spray printing, and screen printing, depending on the viscosity of the varnish. In addition,
The thickness of the film can be adjusted by the application conditions, the solid content concentration of the present composition, and the like. Further, the coating formed on the support in advance is peeled off from the support to form a sheet made of the heat-resistant photosensitive resin composition, and the sheet is attached to the surface of the support substrate to form the above-described coating. May be formed.

Next, after irradiating the film with light (usually using ultraviolet light) through a photomask having a predetermined pattern, the unexposed portion is dissolved and removed with an organic solvent or a basic aqueous solution to obtain a desired film. A relief pattern can be obtained. Irradiation light may be ultraviolet light, electron beam or the like, and the composition of the present invention is particularly suitable for i-ray exposure (for example, using an i-ray stepper as an apparatus) for irradiating 365 nm i-ray as monochromatic light. is there. As a solution used for the development, an organic solvent, a basic aqueous solution, or the like can be used, and a basic aqueous solution is preferable in terms of environmental resistance and the like.

As the organic solvent, γ-butyrolactone,
Examples thereof include cyclopentanone, N-methylpyrrolidone, dimethylsulfoxide, dimethylacetamide, and a mixed solution thereof. The basic aqueous solution is usually a solution in which a basic compound is dissolved in water. The concentration of the basic compound is
The content is usually 0.1 to 50% by weight, preferably from the influence on the supporting substrate and the like, and more preferably 0.1 to 30% by weight. In order to improve the solubility of the polyimide precursor, methanol, ethanol, propanol, isopropyl alcohol, N-methyl-2-pyrrolidone,
A water-soluble organic solvent such as N, N-dimethylformamide and N, N-dimethylacetamide may be further contained.

Examples of the basic compound include hydroxides or carbonates of alkali metals, alkaline earth metals or ammonium ions, amine compounds, and the like. Specific examples include 2-dimethylaminoethanol, 3
-Dimethylamino-1-propanol, 4-dimethylamino-1-butanol, 5-dimethylamino-1-pentanol, 6-dimethylamino-1-hexanol,
-Dimethylamino-2-methyl-1-propanol, 3
-Dimethylamino-2,2-dimethyl-1-propanol, 2-diethylaminoethanol, 3-diethylamino-1-propanol, 2-diisopropylaminoethanol, 2-di-n-butylaminoethanol, N, N
-Dibenzyl-2-aminoethanol, 2- (2-dimethylaminoethoxy) ethanol, 2- (2-diethylaminoethoxy) ethanol, 1-dimethylamino-2
-Propanol, 1-diethylamino-2-propanol, N-methyldiethanolamine, N-ethyldiethanolamine, Nn-butyldiethanolamine, N
-T-butyldiethanolamine, N-lauryldiethanolamine, 3-diethylamino-1,2-propanediol, triethanolamine, triisopropanolamine, N-methylethanolamine, N-ethylethanolamine, Nn-butylethanolamine, N
-T-butylethanolamine, diethanolamine,
Diisopropanolamine, 2-aminoethanol, 3
-Amino-1-propanol, 4-amino-1-butanol, 6-amino-1-hexanol, 1-amino-2
-Propanol, 2-amino-2,2-dimethyl-1-
Propanol, 1-aminobutanol, 2-amino-1
-Butanol, N- (2-aminoethyl) ethanolamine, 2-amino-2-methyl-1,3-propanediol, 2-amino-2-ethyl-1,3-propanediol, 3-amino-1, 2-propanediol, 2-amino-2-hydroxymethyl-1,3-propanediol, sodium hydroxide, potassium hydroxide, ammonium hydroxide, sodium carbonate, potassium carbonate, ammonium carbonate, sodium hydrogen carbonate, potassium hydrogen carbonate, Ammonium hydrogen carbonate, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetraisopropylammonium hydroxide, aminomethanol, 2-aminoethanol, 3-aminopropanol, 2-aminopropanol, Triethanolamine, ethylamine, propylamine, isopropylamine, dimethylamine, diethylamine, dipropylamine, diisopropylamine,
It is preferable to use trimethylamine, triethylamine, tripropylamine, triisopropylamine and the like, but other compounds may be used as long as they are soluble in water and the aqueous solution exhibits basicity.

When a photosensitive resin composition containing a polyimide precursor is used, the obtained relief pattern is preferably subjected to a heat treatment at a temperature selected from the range of 150 ° C. to 450 ° C. to obtain a pattern made of polyimide. can do. This pattern has high resolution, high heat resistance, and excellent mechanical properties.

The heat-resistant photosensitive resin composition of the present invention can be used for electronic parts such as semiconductor devices and multilayer wiring boards. Specifically, the surface protective films (buffer coat films, passivation films, etc.) of semiconductor devices can be used. , Α-ray shielding film, etc.), an interlayer insulating film, an interlayer insulating film of a multilayer wiring board, and the like.

The electronic component of the present invention is not particularly limited except that it has a surface protective film and an interlayer insulating film formed using the composition, and can have various structures.

An example of a manufacturing process of a semiconductor device as an electronic component will be described below. FIG. 1 is a manufacturing process diagram of a semiconductor device having a multilayer wiring structure. In the figure, a semiconductor substrate such as a Si substrate having a circuit element is covered with a protective film 2 such as a silicon oxide film except for a predetermined portion of the circuit element, and a first conductor layer is formed on the exposed circuit element. . A film 4 of a polyimide resin or the like as an interlayer insulating film is formed on the semiconductor substrate by a spin coating method or the like (step (a)).

Next, a photosensitive resin layer 5 of a chlorinated rubber type, a phenol novolak type or the like is formed on the interlayer insulating film 4 by spin coating, and a predetermined portion of the interlayer insulating film 4 is exposed by a known photolithography technique. A window 6A is provided to perform the process (step (b)). The interlayer insulating film 4 in the window 6A is selectively etched by a dry etching means using a gas such as oxygen or carbon tetrafluoride, and a window 6B is opened. Next, the photosensitive resin layer 5 is completely removed by using an etching solution that corrodes only the photosensitive resin layer 5 without corroding the first conductor layer 3 exposed from the window 6B (step (c)).

Further, using a known photolithography technique,
The conductor layer 7 is formed, and the electrical connection with the first conductor layer 3 is made completely (step (d)). When a multilayer wiring structure of three or more layers is formed, the above steps are repeated to form each layer.

Next, a surface protection film 8 is formed. In the example of this figure, the surface protective film is coated with the heat-resistant photosensitive resin composition by a spin coating method and dried, and a window 6C is formed on a predetermined portion.
After irradiating light from above the mask on which the pattern for forming the pattern is drawn, the pattern is formed by developing with a developer. When the heat-resistant photosensitive resin composition contains a polyimide precursor, it is heated to form a polyimide film. This polyimide film protects the conductor layer from external stress, α-rays and the like, and the resulting semiconductor device has excellent reliability. In the above example, the interlayer insulating film can be formed by using the heat-resistant photosensitive resin composition of the present invention, whereby the resist coating and etching steps can be omitted.

[0053]

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

Synthesis Example 1 Preparation of bissulfonium borate compound (1) Synthesis of sodium salt of triphenylbenzyl borate Trifluoroboron-diethyl ether complex (4.02)
g, 0.0282 mol) of diethyl ether (10 ml)
While cooling the solution in an ice bath, 0.86 of phenyllithium was added.
N cyclohexane-diethyl ether solution (100 ml,
0.086 mol) was added dropwise. After dropping, add 2
For a further 2 hours at 40 ° C. The solvent was distilled off under reduced pressure, and the solvent was converted by adding tetrahydrofuran (10 ml). Then, a 1.25N diethyl ether solution of benzylmagnesium chloride (30 ml, 0.037 ml) was added.
5 mol) was added dropwise at an ice temperature. After dropping, add 2
After stirring for a while, a 13% aqueous solution of sodium hydroxide (2
30 ml). A saturated saline solution (300 ml) was added to the reaction solution.
Was added, the organic layer was separated, and the aqueous layer was extracted with tetrahydrofuran (50 ml). The organic layers were combined, dried under reduced pressure, saturated brine (130 ml) was added, and extracted with ethyl acetate (30 ml × 5). The organic layer was concentrated under reduced pressure to give 8.28 g of the desired product as a white solid (yield 75.
0%).

(2) bissulfonium borate (S-
Synthesis of 1) 31.71 g (0.33 mol) of methanesulfonic acid and 3.41 g (0.024 mol) of phosphorus pentoxide were charged, and 70 ° C.
And stirred for 3 hours, and the resulting homogeneous solution was cooled to room temperature. 7.86 g (0.033 mol) of 4,4'-difluorodiphenyl sulfoxide and 3.07 g (0.0165 mol) of diphenyl sulfide were charged into this solution and stirred at room temperature for 5 hours. The reaction mixture was added dropwise to 380 ml (0.0333 mol) of a 3% by weight aqueous solution of sodium tetraphenylborate while stirring, and the mixture was stirred at room temperature for 3 hours. The precipitated solid was collected by filtration, dried, dissolved in isopropanol by heating (70 ° C.), cooled to 0 ° C., filtered, and dried.
4.18 g (0.0112 mol) were obtained.

[0056]

Embedded image

The product was identified by the following method, and the production of the target product was confirmed. [Elemental analysis value] C; Calculated value 79.6, Analytical value 79.2 H; Calculated value 5.1, Analytical value 5.4 [Infrared absorption spectrum] (Attached Fig. 2) νB-C = 705 cm ^-1 , 735 cm ^-1 [FD-MS] m / z = 629

(3) bissulfonium borate (S-
Synthesis of 2) 24.70 g (0.16 mol) of methanesulfonic acid and 1.56 g (0.011 mol) of phosphorus pentoxide were charged at 70 ° C.
And stirred for 3 hours, and the resulting homogeneous solution was cooled to room temperature. 3.81 g (0.016 mol) of 4,4'-difluorodiphenylsulfoxide and 1.49 g (0.008 mol) of diphenylsulfide were charged into this solution, and the mixture was stirred at room temperature for 5 hours. The reaction mixture is added to water 300
Then, 5.70 g of triphenylbenzyl borate sodium salt obtained in (1) (0.
016 mol) and stirred at room temperature for 3 hours. The precipitated solid was collected by filtration, dried, dissolved in isopropanol by heating (70 ° C.), cooled to 0 ° C., filtered, and dried to obtain 6.73 g (0.0052 mol) of the desired product as a white solid. Was.

[0059]

Embedded image

The product was identified by the following method, and the production of the target product was confirmed. [Elemental analysis value] C: calculated value 79.8, analyzed value 79.1, H: calculated value 5.3, analyzed value 5.1 [infrared absorption spectrum] (FIG. 3 attached) νB−C = 705 cm ^{− 1} , 735 cm ^-1 [FD-MS] m / z = 629

Synthesis Example 2 Synthesis of Polyimide Precursor (1) Synthesis of acid chloride 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride (BPDA) 9.4 was placed in a 200 ml four-necked flask.
2 g (0.032 mol), 8.32 g (0.064 mol) of 2-hydroxyethyl methacrylate (HEMA),
5.06 g (0.064 mol) of pyridine, 0.03 g of t-butylcatechol, N-methyl-2-pyrrolidone (N
(MP) and stirred at 60 ° C., resulting in a clear solution in 2 hours. After stirring the solution at room temperature for 7 hours, the flask was cooled with ice and thionyl chloride 9.88.
g (0.083 mol) was added dropwise in 10 minutes. Thereafter, the mixture was stirred at room temperature for 1 hour to obtain a solution containing acid chloride.

(2) Synthesis of Polyimide Precursor (Polyamic Acid Ester) In another 200 ml four-necked flask, 4.72 g (0.031 mol) of 3,5-diaminobenzoic acid and 5.0 parts of pyridine were added.
6 g (0.064 mol), t-butylcatechol 0.0
3 g and 50 ml of N-methyl-2-pyrrolidone (NMP) were added, and the acid chloride solution obtained above was slowly added dropwise over 1 hour while cooling the flask with ice and stirring (maintaining at 10 ° C. or lower). Thereafter, the mixture was stirred at room temperature for 1 hour, poured into 1 liter of water, and the precipitated polymer was collected by filtration, washed twice with water, and dried under vacuum.
2 g were obtained. When the weight average molecular weight of this polyamic acid ester was measured by GPC (gel permeation chromatography), it was 44,000 in terms of polystyrene.
It was 0.

Examples 1, 2, 3 (1) Preparation of polyimide precursor composition 1 10 g of the above polyimide precursor resin was dissolved in γ-butyrolactone (13.8 g), and tetraethylene glycol diacrylate (2.0 g) was dissolved. ) And the photosensitive agent shown in Table 1 were filtered under pressure using a filter having a pore size of 3 μm to obtain a photosensitive resin composition in a solution state.

[0064]

[Table 1]

Table 1 shows the amounts of the photosensitive polyimide precursor 10
0 parts by weight of the photoinitiator with respect to 20 parts by weight of the crosslinking agent (tetraethylene glycol diacrylate) (part by weight). S-1: bissulfonyl triphenylbutyl borate, S-2: bissulfonyl triphenylbenzyl borate, PDO: 1-phenyl-1,2-propanedione-2-
(O-ethoxycarbonyl) oxime, EMK: 4,4'-bisdiethylamino Michler's ketone, NPG: N-phenylglycine

(2) Formation of Pattern The photosensitive resin composition prepared in (1) is spin-coated on a silicon wafer, and heated on a hot plate at 85 ° C. for 100 seconds.
The coating was further heated at 95 ° C. for 100 seconds to obtain a coating film having a thickness of 12 μm. The coating film was exposed to 50 to 850 (mJ / cm ² ) in 50 (mJ / cm ² ) steps using an i-line stepper. At this time, the mask pattern was evaluated using an opening pattern for evaluating resolution. Thereafter, development was performed with a 2.38% by weight aqueous solution of tetramethylammonium hydroxide, and rinsing was performed with water. The thickness and shape of the pattern after development were measured and observed.
Table 2 shows the exposure dose, sensitivity (mJ / cm ² ) and resolution (μm) required for pattern formation.

[0067]

[Table 2]

(3) Formation of Polyimide Film Using the pattern of Example-3 obtained in (2) above,
Under a nitrogen atmosphere, 100 ° C. for 30 minutes, 200 ° C. for 30 minutes
And then heated at 350 ° C. for 60 minutes to obtain a polyimide pattern. The thickness of the obtained polyimide pattern is 9.0 μm.
m, and a good polyimide pattern was obtained.

[0069]

The heat-resistant photosensitive resin composition of the present invention has higher sensitivity than conventional ones, has excellent photosensitive characteristics, and can provide a good pattern having excellent shape even at a low exposure dose. It is. In particular, it is suitable for exposure with i-line monochromatic light.
Further, according to the method for producing a pattern of the present invention, a good pattern having high sensitivity, excellent photosensitive characteristics, and excellent shape even at a low exposure dose can be obtained as compared with the conventional one. Further, the electronic component of the present invention has excellent reliability by having the pattern.

[Brief description of the drawings]

FIG. 1 is a manufacturing process diagram of a semiconductor device having a multilayer wiring structure.

FIG. 2 is an infrared absorption spectrum of the bissulfonium borate compound of the present invention.

FIG. 3 is an infrared absorption spectrum of the bissulfonium borate compound of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 semiconductor substrate 2 protective film 3 first conductor layer 4 interlayer insulating film layer 5 photosensitive resin layer 6A, 6B, 6C window 7 second conductor layer 8 surface protective film layer

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08L 79/08 C08L 79/08 A 5E346 101/00 101/00 G03F 7/027 514 G03F 7/027 514 7 / 037 501 7/037 501 H01L 21/027 H05K 3/46 T H05K 3/46 H01L 21/30 502R F term (reference) 2H025 AA04 AA08 AA10 AB15 AB16 AB17 AC01 BC14 BC34 BC43 BC53 BC69 BD43 CA30 CA43 CB25 4F071 AA60 AC AH12 BA02 BC01 4J002 CL001 CM011 CM041 EV046 EV056 GP03 4J011 QA09 QA11 QA13 QA17 QA23 QA24 QA39 QB17 QB18 SA01 SA05 SA21 SA25 SA75 UA01 WA01 4J027 AC03 AC04 AD02 AD03 AD06 BA05 BA08 CC14 BA18 BA10 CC20 BA20 BA20 BA10 CC20 DD44 EE31 EE39 GG18 GG19 HH26

Claims (8)

[Claims] 1. A heat-resistant photosensitive resin composition comprising a bissulfonium borate compound and a heat-resistant resin. 2. A bissulfonium borate compound represented by the general formula (I): (In the formula, each X is independently an alkyl group having 1 to 12 carbon atoms, the alkyl group substituted with a hydroxyl group or a halogen atom, and R ¹ , R ² , R ³ and R ⁴ are each independently The heat-resistant photosensitive resin composition according to claim 1, which is a compound represented by the formula: an alkyl group having 1 to 12 carbon atoms, a phenyl group, a benzyl group, a substituted phenyl group or a substituted benzyl group). 3. The bissulfonium borate compound represented by the general formula (II): The heat-resistant photosensitive resin composition according to claim 1, which is a compound represented by the formula: 4. A bissulfonium borate compound represented by the following general formula (III): The heat-resistant photosensitive resin composition according to claim 1, which is a compound represented by the formula: 5. The heat-resistant photosensitive resin composition according to claim 1, wherein the heat-resistant resin is a polyimide precursor. 6. The heat-resistant photosensitive resin composition according to claim 5, wherein the polyimide precursor has a carbon-carbon unsaturated double bond. 7. A step of forming a film using the heat-resistant photosensitive resin composition according to any one of claims 1 to 6, a step of irradiating the film with light through a mask having a predetermined pattern, and A method for producing a pattern, comprising a step of developing the film after the light irradiation using an organic solvent or a basic aqueous solution. 8. An electronic component having a pattern obtained by the method according to claim 7 as a film.