JP2026005560A - Photosensitive resin composition, method for producing cured relief pattern, cured relief pattern, and semiconductor device - Google Patents

Abstract

The present invention provides a photosensitive resin composition that has good mechanical properties, good adhesion to metal electrodes, and high resolution, and is capable of forming fine patterns; a cured relief pattern produced using the photosensitive resin composition; a method for producing the cured relief pattern; and a semiconductor device.
(A) a polyimide precursor containing a repeating unit represented by a specific formula;
(B) a photoradical initiator,
(D) the following general formula (2):

(wherein n is an integer of 0 to 2, l is an integer of 2 to 4, and _R3 is a functional group containing a heteroatom), and (E) a phenol-based polymerization inhibitor.
[Selection diagram] None

Description

The present invention relates to a photosensitive resin composition containing a polyimide precursor, a method for producing a cured relief pattern obtained by curing the photosensitive resin composition, the cured relief pattern, and a semiconductor device having the cured relief pattern.

Polyimide resins, which combine excellent heat resistance with excellent electrical and mechanical properties, have traditionally been used as insulating materials for electronic components, and for passivation films, surface protection films, and interlayer insulating films for semiconductor devices. Among these polyimide resins, those provided as photosensitive polyimide precursor compositions can easily form heat-resistant cured relief pattern coatings by applying the composition, exposing it to light, developing it, and subjecting it to a thermal imidization treatment involving curing. Such photosensitive polyimide precursor compositions have the advantage of enabling significant process reductions compared to conventional non-photosensitive polyimide materials.

As semiconductor device integration and functionality improve, and chip sizes become smaller, the methods for mounting semiconductor devices to printed wiring boards are also changing. Conventional mounting methods using metal pins and lead-tin eutectic solder are being replaced by structures in which a polyimide coating directly contacts the solder bumps, such as those used in BGA (ball-gripped array) and CSP (chip-size packaging), which enable higher-density mounting. When forming such bump structures, the coating must have high heat resistance and mechanical properties.

In recent years, in order to improve integration and functionality, as well as to reduce chip size, methods such as BGA (ball-gripped array) and CSP (chip-size packaging), which enable high-density mounting, have been used to mount semiconductor devices on printed wiring boards. In these processes, a photosensitive polyimide coating is formed on the surface of the semiconductor element, and protruding electrodes (bumps) for connection to the substrate are formed on the polyimide pattern formed by photolithography.

In the above-mentioned mounting method, the polyimide coating applied to the buffer coat layer is required to have a high Young's modulus in order to relieve the stress applied from the bumps to the semiconductor element during the semiconductor mounting process.
For example, Patent Document 1 discloses a resin composition that forms a cured film, which contains a polyimide precursor having a specific structure and a photopolymerizable compound, and which has both a high Young's modulus and low residual stress.

Japanese Patent Application Laid-Open No. 2020-037699

However, one problem with existing photosensitive polyimide resins for buffer coating applications is their poor adhesion to the aluminum that forms the semiconductor electrodes. As a result, delamination can occur between the polyimide resin and the substrate, potentially reducing the reliability of the semiconductor device.

Furthermore, in recent years, as semiconductor devices have become increasingly smaller and more densely packed, there has been a demand for narrower electrodes on the surface of semiconductor chips. Accordingly, the photosensitive polyimide resin used in the buffer coating layer is required to have high resolution, capable of forming fine patterns of, for example, 5 μm or less.

The present invention aims to provide a photosensitive resin composition that has good mechanical properties, good adhesion to metal (especially aluminum) electrodes, and exhibits high resolution, and is capable of forming fine patterns; a cured relief pattern produced using the photosensitive resin composition; a method for producing a cured relief pattern; and a semiconductor device.

That is, the present invention is as follows.
[Section 1]
(A) The following general formula (1):
(wherein _X1 is a tetravalent organic group, _Y1 is a divalent organic group, m is an integer of 2 or more, and _R1 and _R2 each independently represent a hydrogen atom or a monovalent organic group),
(B) a photoradical initiator,
(D) the following general formula (2):
(wherein n is an integer of 0 to 2, l is an integer of 2 to 4, and _R3 is a functional group containing a heteroatom), and (E) a phenol-based polymerization inhibitor.
[Section 2]
The compound (D) is represented by the following general formula (3):
(wherein R4 _{, R5} , and _R6 each independently represent a hydrogen atom or a functional group containing a heteroatom, and at least one of R4 _{, R5} , and _R6 is a hydrogen atom).
[Section 3]
Item 3. The photosensitive resin composition according to Item 1 or 2, wherein the functional group containing a hetero atom is an amino group, a hydroxy group, or a mercapto group.
[Section 4]
Item 4. The photosensitive resin composition according to any one of Items 1 to 3, wherein the (E) phenolic polymerization inhibitor includes 4-methoxyphenol.
[Section 5]
Item 5. The photosensitive resin composition according to any one of Items 1 to 4, further comprising (C) a radically polymerizable compound.
[Section 6]
Item 6. The photosensitive resin composition according to Item 5, wherein the (C) radically polymerizable compound includes a compound having two radically polymerizable groups and a compound having three or more radically polymerizable groups.
[Section 7]
The Y ₁ is represented by the following general formula (5):
(wherein R ₇ and R ₈ each independently represent a hydrogen atom, a methyl group, a fluorine atom, or a trifluoromethyl group).
[Section 8]
Item 8. The photosensitive resin composition according to any one of Items 1 to 7, comprising two or more kinds of (E) phenolic polymerization inhibitors.
[Section 9]
(1) A step of forming a photosensitive resin layer on a substrate by applying the photosensitive resin composition according to any one of items 1 to 8 onto the substrate;
(2) exposing the photosensitive resin layer to light;
(3) developing the exposed photosensitive resin layer to form a relief pattern;
(4) forming a hardened relief pattern by heat-treating the relief pattern;
1. A method for producing a cured relief pattern, comprising:
[Section 10]
Item 9. A cured relief pattern comprising a cured product of the photosensitive resin composition according to any one of Items 1 to 8.
[Section 11]
Item 11. A semiconductor device comprising the cured relief pattern according to item 10.

The present invention provides a photosensitive resin composition that exhibits excellent adhesion to metal electrodes in semiconductor elements and high resolution, a method for producing a cured relief pattern using the photosensitive resin composition, a cured relief pattern, and a semiconductor device having the cured relief pattern.

The following describes in detail the mode for carrying out the present invention (hereinafter referred to as the "present embodiment"). Note that the present invention is not limited to the following present embodiment, and various modifications can be made within the scope of its gist.

In an embodiment, the photosensitive resin composition contains (A) a polyimide precursor, (B) a photoradical initiator, (D) a specific compound, (E) a phenolic polymerization inhibitor, and optionally a solvent and other components. Each component will be described below.
The photosensitive resin composition of the present embodiment can be used as a negative photosensitive resin composition or a positive photosensitive resin composition.

Throughout this specification, when multiple structures represented by the same symbol in a general formula are present in a molecule, they may be the same or different.

<Photosensitive resin composition>
(A) Polyimide Precursor The polyimide precursor used in the photosensitive resin composition of the present embodiment is a polyimide precursor represented by the following general formula (1):
{In the formula, _X1 is a tetravalent organic group, _Y1 is a divalent organic group, m is an integer of 2 or more, and _R1 and _R2 are each independently a hydrogen atom or a monovalent organic group.}
A polyamic acid ester containing a repeating unit represented by the following formula is used.
It is preferable that neither R ₁ nor R ₂ is a hydrogen atom, and it is preferable that either R ₁ or R ₂ contains a radical polymerizable group.

Multiple polyamic acid esters represented by general formula (1) may be mixed to form the polyimide precursor of this embodiment. Furthermore, polyamic acid esters obtained by copolymerizing polyamic acid esters represented by general formula (1) may also be used.

In one embodiment, the (A) polyimide precursor may have a polymerizable group (in one embodiment, a radically polymerizable group) in a side chain. The (A) polyimide precursor having a polymerizable group in a side chain can be obtained, for example, by reacting a tetracarboxylic acid dianhydride with an alcohol (a) described below, and then reacting the alcohol with a diamine.

In general formula (1), the tetravalent organic group represented by _X1 is not particularly limited, but is preferably an organic group having 6 to 40 carbon atoms, and more preferably an aromatic group or an alicyclic aliphatic group in which the _-COOR1 group, the _-COOR2 group, and the -CONH- group are located at the ortho positions relative to each other.

From the viewpoint of improving the film properties of the cured relief pattern, the tetravalent organic group represented by _X1 in the general formula (1) preferably includes at least one of pyromellitic dianhydride (PMDA) and biphenyltetracarboxylic dianhydride (BPDA).
In addition, from the viewpoint of the absorbance of the polyimide precursor and the elongation of the cured relief pattern, it is preferable that the polyimide precursor contains 4,4'-oxydiphthalic dianhydride (ODPA).

In the general formula (1), the divalent organic group represented by _Y1 is not particularly limited, but from the viewpoint of _Young 's modulus and chemical resistance, it is preferably a divalent organic group containing an aromatic group.
Specifically, Y ₁ is represented by the following general formula (5):
(wherein _R7 and _R8 each independently represent a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group) and a compound represented by general formula (6):
(In the formula, R ₁₀ represents either a hydrogen atom or a methyl group.)
It is preferable that Y1 is a divalent organic group containing at least one structure represented by the following formula: Furthermore, the structure of _Y1 may be one type alone or a combination of two or more types.
From the viewpoint of resolution, it is preferable that Y ₁ contains a structure represented by the general formula (5), and from the viewpoint of mechanical properties, it is particularly preferable that R ₇ and R ₈ in formula (5) are methyl groups.

[(A) Method for preparing polyimide precursor]
The polyimide precursor represented by the general formula (1) in this embodiment can be obtained, for example, by reacting the above-mentioned tetracarboxylic acid dianhydride containing the tetravalent organic group _X1 having 6 to 40 carbon atoms with (a) an alcohol to prepare a partially esterified tetracarboxylic acid (hereinafter also referred to as an acid/ester), and subsequently polycondensing the resulting tetracarboxylic acid with a diamine containing the divalent organic group _Y1 represented by the above-mentioned general formula (5) or general formula (6).

(Preparation of Acid/Ester Form)
In this embodiment, a tetravalent organic group X having 6 to 40 carbon atoms Examples of tetracarboxylic dianhydrides containing ₁ include 4,4'-oxydiphthalic dianhydride (ODPA), pyromellitic anhydride (PMDA), benzophenone-3,3',4,4'-tetracarboxylic dianhydride, biphenyl-3,3',4,4'-tetracarboxylic dianhydride (BPDA), 9,9-bis(3,4-dicarboxyphenyl)fluorene dianhydride, bis(1,3-dioxo-1,3-dihydroisobenzofuran-5-carboxylic acid)1,4-phenylene, diphenylsulfone-3,3',4,4'-tetracarboxylic dianhydride, diphenylmethane-3,3',4,4'-tetracarboxylic dianhydride, 2,2-bis(3,4-phthalic anhydride)propane and 2,2-bis(3,4-phthalic anhydride)-1,1,1,3,3,3-hexafluoropropane. These may be used alone or in combination of two or more.

By dissolving and mixing the above-mentioned tetracarboxylic dianhydride and (a) alcohol in a reaction solvent in the presence of a basic catalyst such as pyridine, the half-esterification reaction of the acid dianhydride proceeds, yielding the desired acid/ester. The reaction conditions are preferably a reaction temperature of 20 to 50°C and stirring for 4 to 30 hours.

The reaction solvent is preferably one that dissolves the acid/ester compound and the polyimide precursor, which is a polycondensation product of the acid/ester compound and a diamine.
Examples of reaction solvents include N-methyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-dimethylformamide, dimethyl sulfoxide, tetramethylurea, gamma butyrolactone, ketones, esters, lactones, ethers, halogenated hydrocarbons, hydrocarbons, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, methyl acetate, ethyl acetate, butyl acetate, diethyl oxalate, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, tetrahydrofuran, dichloromethane, 1,2-dichloroethane, 1,4-dichlorobutane, chlorobenzene, o-dichlorobenzene, hexane, heptane, benzene, toluene, and xylene. These may be used alone or in combination as needed.

Examples of diamines containing a divalent organic group _Y1 that can be suitably used in this embodiment include 2,2'-dimethyl-4,4-diaminobiphenyl (m-TB), 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4'-diaminodiphenylmethane, 2,2'-dimethyl-4,4'-diaminodiphenylmethane, 2,2'-dimethoxy-4,4'-diaminobiphenyl, 3,3'-dimethytoxy-4,4'-diaminobiphenyl, 2,2',3,3'-tetramethyl-4,4-diaminobiphenyl, 3,3'-dichloro-4,4'-diaminobiphenyl, p-phenylenediamine, 2,5-dimethyl-1,4-phenylenediamine, and 4,4'-oxydianiline (ODA). These may be used alone or in combination of two or more.
Among these, it is preferable to use 2,2'-dimethyl-4,4'-diaminobiphenyl, 2,2'-dimethoxy-4,4'-diaminobiphenyl, and p-phenylenediamine, and it is more preferable to use 2,2'-dimethyl-4,4'-diaminobiphenyl and p-phenylenediamine.

The alcohol (a) used in the esterification reaction of the tetracarboxylic dianhydride can be an alcohol having an olefinic double bond.
Specific examples of alcohols having an olefinic double bond include 2-hydroxyethyl methacrylate (HEMA), 2-methacryloyloxyethyl alcohol, glycerin diacrylate, glycerin dimethacrylate, 2-acryloyloxyethyl alcohol, 1-acryloyloxy-3-propyl alcohol, 2-acrylamidoethyl alcohol, methylol vinyl ketone, 2-hydroxyethyl vinyl ketone, 2-hydroxy-3-methoxypropyl acrylate, 2-hydroxy-3-butoxypropyl acrylate, 2-hydroxy-3-phenoxypropyl acrylate, 2-hydroxy-3-butoxypropyl acrylate, 2-hydroxy-3- Examples of alcohols include, but are not limited to, t-butoxypropyl acrylate, 2-hydroxy-3-cyclohexyloxypropyl acrylate, 2-methacryloyloxyethyl alcohol, 1-methacryloyloxy-3-propyl alcohol, 2-methacrylamidoethyl alcohol, 2-hydroxy-3-methoxypropyl methacrylate, 2-hydroxy-3-butoxypropyl methacrylate, 2-hydroxy-3-phenoxypropyl methacrylate, 2-hydroxy-3-butoxypropyl methacrylate, 2-hydroxy-3-t-butoxypropyl methacrylate, and 2-hydroxy-3-cyclohexyloxypropyl methacrylate. These alcohols can be used alone or in combination of two or more. Furthermore, as the (a) alcohol, an alcohol not having an olefinic double bond may also be used.

After the reaction is complete, any water-absorbing by-products of the dehydration condensation agent present in the reaction solution are filtered off, if necessary. A poor solvent, such as water, a lower aliphatic alcohol, or a mixture thereof, is then added to the resulting polymer component to precipitate the polymer component. The polymer is then purified by repeated redissolution and reprecipitation procedures, and the polymer is then vacuum dried to isolate the desired polyimide precursor. To improve the degree of purification, the polymer solution may be passed through a column packed with anion exchange resin and/or cation exchange resin swollen with an appropriate organic solvent to remove ionic impurities.

Examples of dehydration condensation agents include dicyclohexylcarbodiimide (DCC), diethylcarbodiimide, diisopropylcarbodiimide, ethylcyclohexylcarbodiimide, diphenylcarbodiimide, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide, and 1-cyclohexyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride.

(B) Photoradical initiator (B) is not particularly limited as long as it is a compound that generates radicals upon irradiation with light, and any compound conventionally used as a photoradical initiator for UV curing can be selected.
For example, benzophenone derivatives such as benzophenone, methyl o-benzoylbenzoate, 4-benzoyl-4'-methyldiphenyl ketone, dibenzyl ketone, and fluorenone;
Acetophenone derivatives such as 2,2'-diethoxyacetophenone, 2-hydroxy-2-methylpropiophenone, and 1-hydroxycyclohexyl phenyl ketone;
Thioxanthone, thioxanthone derivatives such as thioxanthone, 2-methylthioxanthone, 2-isopropylthioxanthone, and diethylthioxanthone;
benzil, benzil dimethyl ketal, benzil β-methoxyethyl acetal and other benzil derivatives;
benzoin and benzoin derivatives such as benzoin methyl ether;
oximes such as 1-phenyl-1,2-butanedione-2-(O-methoxycarbonyl)oxime, 1-phenyl-1,2-propanedione-2-(O-methoxycarbonyl)oxime, 1-phenyl-1,2-propanedione-2-(O-ethoxycarbonyl)oxime, 1-phenyl-1,2-propanedione-2-(O-benzoyl)oxime, 1,3-diphenylpropanetrione-2-(O-ethoxycarbonyl)oxime, and 1-phenyl-3-ethoxypropanetrione-2-(O-benzoyl)oxime;
Preferred examples include, but are not limited to, N-arylglycines such as N-phenylglycine; peroxides such as benzoyl perchloride; and aromatic biimidazoles.
These may be used alone or in combination of two or more. Among the above-mentioned (B) photoradical initiators, oximes are more preferred in terms of photosensitivity.

The content of the photoradical initiator (B) is preferably 0.1 to 20 parts by mass, and more preferably 1 to 15 parts by mass, relative to 100 parts by mass of the polyimide precursor (A), from the viewpoint of photosensitivity characteristics.
By including 0.1 parts by mass or more of the photoradical initiator (B) relative to 100 parts by mass of the polyimide precursor (A), the photosensitive resin composition of the present embodiment has excellent photosensitivity, while by including 20 parts by mass or less of the photoradical initiator (B) relative to 100 parts by mass of the polyimide precursor (A), the photosensitive resin composition of the present embodiment has excellent thick-film curing properties.

(C) Radically Polymerizable Compound In order to improve the resolution of the cured relief pattern, (C) a radically polymerizable compound may be optionally contained in the photosensitive resin composition of this embodiment.
The (C) radically polymerizable compound is preferably a (meth)acrylic compound that undergoes a radical polymerization reaction in the presence of a photoradical initiator, and is not particularly limited thereto. From the viewpoint of resolution, however, it is preferable that the compound include a compound having two radically polymerizable groups and a compound having three or more radically polymerizable groups.
(C) Examples of the radical polymerizable compound include mono- or diacrylates and methacrylates of ethylene glycol or polyethylene glycol, such as diethylene glycol dimethacrylate and tetraethylene glycol dimethacrylate;
Mono- or diacrylates and methacrylates of propylene glycol or polypropylene glycol,
Mono-, di- or triacrylates and methacrylates of glycerol,
cyclohexane diacrylate and dimethacrylate,
Diacrylate and dimethacrylate of 1,4-butanediol,
Diacrylate and dimethacrylate of 1,6-hexanediol,
Neopentyl glycol diacrylate and dimethacrylate,
Mono- and diacrylates and methacrylates of bisphenol A,
Examples of such compounds include benzene trimethacrylate, isobornyl acrylate and methacrylate, acrylamide and its derivatives, methacrylamide and its derivatives, trimethylolpropane triacrylate and methacrylate, di- or triacrylate and methacrylate of glycerol, di-, tri-, or tetraacrylate and methacrylate of pentaerythritol, tris-(2-acryloxyethyl)isocyanurate, and ethylene oxide or propylene oxide adducts of these compounds, which may be used alone or in combination of two or more.

The content of (C) radically polymerizable compound is preferably 1 to 80 parts by mass per 100 parts by mass of (A) polyimide precursor.

Compound (D) Compound (D) is represented by the following general formula (2):
(wherein n is an integer of 0 to 2, l is an integer of 2 to 4, and _R3 is a functional group containing a hetero atom).
The heteroatom-containing functional group may, in one embodiment, be an amino group, a hydroxy group, or a mercapto group.

From the viewpoint of adhesion to aluminum, the compound (D) is represented by the following general formula (3):
(wherein R4 _{, R5} , and _R6 are each independently a hydrogen atom or a functional group containing a heteroatom, and at least one of R4 _{, R5} , and _R6 is a hydrogen atom)
The heteroatom-containing functional group may, in one embodiment, be an amino group, a hydroxy group, or a mercapto group.

In order to improve the aluminum adhesion of the cured relief pattern, the compound (D) preferably contains a carboxy group and a polar group other than a carboxy group, and the polar group is preferably an amino group, a hydroxy group, or a mercapto group, and from the viewpoint of resolution, an amino group or a hydroxy group is particularly preferred.
Examples of the compound (D) include 2-aminoterephthalic acid, 2-(methylamino)terephthalic acid, 2-mercaptobenzoic acid, 5-aminoisophthalic acid, 5-mercaptoisophthalic acid, 2-hydroxyterephthalic acid, 4-hydroxyisophthalic acid, 5-hydroxyisophthalic acid, 5-methoxyisophthalic acid, 5-mercaptoisophthalic acid, 2,5-dihydroxyisophthalic acid, terephthalic acid, 1,3,5-benzenetricarboxylic acid, and pyromellitic acid.
Among these, 4-hydroxyisophthalic acid and 2,5-dihydroxyisophthalic acid are preferred from the viewpoint of more easily achieving the effects of this embodiment.

The content of the (D) compound is preferably 0.1 to 10 parts by mass, and more preferably 1 to 5 parts by mass, per 100 parts by mass of the (A) polyimide precursor.

While the reason for the effectiveness of this embodiment is unclear, the inventors believe it is as follows: Carboxy groups contained in the (D) compound react with oxygen atoms present in the oxide film formed on the aluminum surface to form ester bonds, and furthermore, polar groups (including carboxy groups) contained in the (D) compound inhibit polymerization of monomers near the aluminum interface, reducing the stress generated by polymerization shrinkage, thereby improving adhesion between the cured film and aluminum.

(E) Phenol-Based Polymerization Inhibitor The photosensitive resin composition of the present embodiment contains (E) a phenol-based polymerization inhibitor from the viewpoint of improving resolution.
The (E) phenolic polymerization inhibitor of the present embodiment is not particularly limited as long as it is a polymerization inhibitor having a phenolic hydroxyl group, and examples thereof include hydroquinone, tert-butylcatechol, parabenzylaminophenol, 4-methoxyphenol, 2-nitroso-5-(N-ethyl-N-sulfopropylamino)phenol, pyrogallol, and hindered phenols.
Among these, the (E) phenolic polymerization inhibitor is preferably hydroquinone, tert-butylcatechol, 4-methoxyphenol, or pyrogallol, and more preferably contains 4-methoxyphenol. These compounds have a relatively small molecular weight (e.g., 300 or less, or 200 or less) and high mobility in the coating film of the photosensitive resin composition, and therefore can more efficiently control the radical polymerization of the photosensitive resin composition.

The (E) phenolic polymerization inhibitor may be used alone or in combination of two or more types. In particular, from the viewpoints of improving the resolution of the photosensitive resin composition of this embodiment and improving its storage stability in a solvent-containing solution state, it is preferable to use two or more types of (E) phenolic polymerization inhibitors in combination. In particular, a combination of 4-methoxyphenol and a hindered phenol is preferred, as this combination provides superior effects in this embodiment.

Examples of hindered phenols include 1,3,5-tris(3-hydroxy-2,6-dimethyl-4-isopropylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-t-butyl-3-hydroxy-2,6-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-s-butyl-3-hydroxy-2,6-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, and 1,3,5-tris[4-(1-ethylpropyl)-3-hydroxy- 2,6-dimethylbenzyl]-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris[4-triethylmethyl-3-hydroxy-2,6-dimethylbenzyl]-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(3-hydroxy-2,6-dimethyl-4-phenylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-t-butyl-3-hydroxy-2,5,6-trimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione , 1,3,5-tris(4-t-butyl-5-ethyl-3-hydroxy-2,6-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-t-butyl-6-ethyl-3-hydroxy-2-methylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-t-butyl-6-ethyl-3-hydroxy-2,5-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-t-butyl-5,6-diethyl-3-hydroxy-2 -methylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-t-butyl-3-hydroxy-2-methylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-t-butyl-3-hydroxy-2,5-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, and 1,3,5-tris(4-t-butyl-5-ethyl-3-hydroxy-2-methylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione.

The content of the phenolic polymerization inhibitor (E) is preferably 1 to 10 parts by mass, and more preferably 2 to 8 parts by mass, per 100 parts by mass of the polyimide precursor (A).
When 4-methoxyphenol is used as the phenolic polymerization inhibitor (E), the content thereof is preferably 1 to 10 parts by mass, and more preferably 2 to 8 parts by mass, per 100 parts by mass of the polyimide precursor (A).

(F) Polymerization inhibitor other than (E) The photosensitive resin composition of the present embodiment preferably contains a polymerization inhibitor other than (E) in order to improve resolution and storage stability in a state of a solution containing a solvent.
Examples of such polymerization inhibitors include N-nitrosodiphenylamine, phenothiazine, N-phenylnaphthylamine, ethylenediaminetetraacetic acid, 1,2-cyclohexanediaminetetraacetic acid, glycol ether diaminetetraacetic acid, 5-nitroso-8-hydroxyquinoline, 1-nitroso-2-naphthol, 2-nitroso-1-naphthol, N-nitroso-N-phenylhydroxylamine ammonium salt, N-nitroso-N(1-naphthyl)hydroxylamine ammonium salt, diphenyl-p-benzoquinone, benzoquinone, phenothiazine, ortho-dinitrobenzene, para-dinitrobenzene, meta-dinitrobenzene, phenanthraquinone, N-phenyl-2-naphthylamine, cupferron, and 2,5-toluquinone.

The content of polymerization inhibitors other than (E) is preferably in the range of 0.005 to 15 parts by mass per 100 parts by mass of (A) polyimide precursor.

Solvent The photosensitive resin composition of the present embodiment may contain a solvent.
As the solvent, it is preferable to use a polar organic solvent in terms of solubility in (A) the polyimide precursor.
Specific examples of the solvent include N,N-dimethylformamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N,N-dimethylacetamide, dimethyl sulfoxide, diethylene glycol dimethyl ether, cyclopentanone, γ-butyrolactone, γ-butyrolactone, α-acetyl-γ-butyrolactone, tetramethylurea, 1,3-dimethyl-2-imidazolinone, N-cyclohexyl-2-pyrrolidone, and 2-octanone, and these can be used alone or in combination of two or more.

The content of the above solvent can be determined depending on the desired coating film thickness and viscosity of the photosensitive resin composition of this embodiment, and can be used in an amount of, for example, 30 to 1,500 parts by weight, preferably 100 to 1,000 parts by weight, per 100 parts by weight of (A) polyimide precursor.

Furthermore, from the viewpoint of improving the storage stability of the photosensitive resin composition of the present embodiment, a solvent containing an alcohol is preferred.
Alcohols that can be suitably used are typically alcohols that have an alcoholic hydroxyl group in the molecule and do not have an olefinic double bond, and alcohols similar to the above-mentioned (a) alcohols can also be used.
Specific examples include alkyl alcohols such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, isobutyl alcohol, and tert-butyl alcohol;
Lactic acid esters such as ethyl lactate;
propylene glycol monoalkyl ethers such as propylene glycol-1-methyl ether, propylene glycol-2-methyl ether, propylene glycol-1-ethyl ether, propylene glycol-2-ethyl ether, propylene glycol-1-(n-propyl) ether, and propylene glycol-2-(n-propyl) ether;
Monoalcohols such as ethylene glycol methyl ether, ethylene glycol ethyl ether, and ethylene glycol-n-propyl ether;
Examples include 2-hydroxyisobutyric acid esters; and dialcohols such as ethylene glycol and propylene glycol.
Among these, lactate esters, propylene glycol monoalkyl ethers, 2-hydroxyisobutyrate esters, and ethyl alcohol are preferred, and ethyl lactate, propylene glycol-1-methyl ether, propylene glycol-1-ethyl ether, and propylene glycol-1-(n-propyl) ether are particularly preferred.

When the solvent contains an alcohol that does not have an olefinic double bond, the content of the alcohol that does not have an olefinic double bond in the total solvent is preferably 5% by mass to 50% by mass, and more preferably 10% by mass to 30% by mass, based on the mass of the total solvent. When the content of the alcohol that does not have an olefinic double bond is 5% by mass or more, the storage stability of the photosensitive resin composition of this embodiment is improved, while when it is 50% by mass or less, the solubility of the (A) polyimide precursor is improved, which is preferable.

<Other ingredients>
In this embodiment, the photosensitive resin composition may further contain components other than the above components (A) to (F). Examples of the other components include resin components other than the polyimide precursor (A), a sensitizer, an adhesion aid, an azole compound, and an organotitanium compound.

The photosensitive resin composition of the present embodiment may further contain a resin component other than the (A) polyimide precursor.
Examples of resin components that can be contained in the photosensitive resin composition of this embodiment include polyimide, polyoxazole, polyoxazole precursor, phenolic resin, polyamide, epoxy resin, siloxane resin, acrylic resin, etc. The content of these resin components is preferably in the range of 0.01 to 20 parts by mass per 100 parts by mass of the (A) polyimide precursor.

The photosensitive resin composition of the present embodiment may optionally contain a sensitizer to improve photosensitivity.
Examples of the sensitizer of the present embodiment include Michler's ketone, 4,4'-bis(diethylamino)benzophenone, 2,5-bis(4'-diethylaminobenzal)cyclopentane, 2,6-bis(4'-diethylaminobenzal)cyclohexanone, 2,6-bis(4'-diethylaminobenzal)-4-methylcyclohexanone, 4,4'-bis(dimethylamino)chalcone, 4,4'-bis(diethylamino)chalcone, and p-dimethylaminocinnamylidene. Indanone, p-dimethylaminobenzylidene indanone, 2-(p-dimethylaminophenylbiphenylene)benzothiazole, 2-(p-dimethylaminophenylvinylene)benzothiazole, 2-(p-dimethylaminophenylvinylene)isonaphthothiazole, 1,3-bis(4'-dimethylaminobenzal)acetone, 1,3-bis(4'-diethylaminobenzal)acetone, 3,3'-carbonyl-bis(7-diethylaminocoumarin), 3- Examples of the methylaminobenzoic acid ester include acetyl-7-dimethylaminocoumarin, 3-ethoxycarbonyl-7-dimethylaminocoumarin, 3-benzyloxycarbonyl-7-dimethylaminocoumarin, 3-methoxycarbonyl-7-diethylaminocoumarin, 3-ethoxycarbonyl-7-diethylaminocoumarin, N-phenyl-N'-ethylethanolamine, N-phenyldiethanolamine, N-p-tolyldiethanolamine, N-phenylethanolamine, 4-morpholinobenzophenone, isoamyl dimethylaminobenzoate, isoamyl diethylaminobenzoate, 2-mercaptobenzimidazole, 1-phenyl-5-mercaptotetrazole, 2-mercaptobenzothiazole, 2-(p-dimethylaminostyryl)benzoxazole, 2-(p-dimethylaminostyryl)benzthiazole, 2-(p-dimethylaminostyryl)naphtho(1,2-d)thiazole, and 2-(p-dimethylaminobenzoyl)styrene. These can be used alone or in combination of two or more (for example, two to five types).

The content of the sensitizer is preferably 0.1 to 25 parts by mass per 100 parts by mass of (A) polyimide precursor.

In order to improve the adhesion between a film formed using the photosensitive resin composition of this embodiment and a substrate, an adhesion aid may be optionally contained in the photosensitive resin composition.
Examples of the adhesion aid of the present embodiment include γ-aminopropyldimethoxysilane, N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-mercaptopropylmethyldimethoxysilane, 3-methacryloxypropyldimethoxymethylsilane, 3-methacryloxypropyltrimethoxysilane, dimethoxymethyl-3-piperidinopropylsilane, diethoxy-3-glycidoxypropylmethylsilane, N-(3-di silane coupling agents such as N-[3-(triethoxysilyl)propyl]succinimide, N-[3-(triethoxysilyl)propyl]phthalamic acid, benzophenone-3,3'-bis(N-[3-triethoxysilyl]propylamido)-4,4'-dicarboxylic acid, benzene-1,4-bis(N-[3-triethoxysilyl]propylamido)-2,5-dicarboxylic acid, 3-(triethoxysilyl)propyl succinic anhydride, and N-phenylaminopropyltrimethoxysilane; and aluminum-based adhesion aids such as aluminum tris(ethylacetoacetate), aluminum tris(acetylacetonate), and ethylacetoacetate aluminum diisopropylate.

Among these adhesion aids, it is more preferable to use a silane coupling agent in terms of adhesion strength. The content of the adhesion aid is preferably in the range of 0.5 to 25 parts by mass per 100 parts by mass of (A) polyimide precursor.

For example, when a substrate made of copper or a copper alloy is used, an azole compound may be optionally contained in the photosensitive resin composition to suppress discoloration of the substrate.
Examples of the azole compound of this embodiment include 1H-triazole, 5-methyl-1H-triazole, 5-ethyl-1H-triazole, 4,5-dimethyl-1H-triazole, 5-phenyl-1H-triazole, 4-t-butyl-5-phenyl-1H-triazole, 5-hydroxyphenyl-1H-triazole, phenyltriazole, p-ethoxyphenyltriazole, 5-phenyl-1-(2-dimethylaminoethyl)triazole, 5-benzyl-1H-triazole, hydroxyphenyltriazole, 1,5-dimethyltriazole, 4,5-diethyl-1H-triazole, 1H-benzotriazole, 2-(5-methyl-2-hydroxyphenyl)benzotriazole, and 2-[2-hydroxy-3,5-bis(α,α-dimethylbenzyl)phenyl] -benzotriazole, 2-(3,5-di-t-butyl-2-hydroxyphenyl)benzotriazole, 2-(3-t-butyl-5-methyl-2-hydroxyphenyl)-benzotriazole, 2-(3,5-di-t-amyl-2-hydroxyphenyl)benzotriazole, 2-(2'-hydroxy-5'-t-octylphenyl)benzotriazole, hydroxyphenylbenzotriazole, tolyltriazole, 5-methyl-1H-benzotriazole, 4-methyl-1H-benzotriazole, 4-carboxy-1H-benzotriazole, 5-carboxy-1H-benzotriazole, 1H-tetrazole, 5-methyl-1H-tetrazole, 5-phenyl-1H-tetrazole, 5-amino-1H-tetrazole and 1-methyl-1H-tetrazole.
Particularly preferred are tolyltriazole, 5-methyl-1H-benzotriazole, and 4-methyl-1H-benzotriazole. These azole compounds may be used alone or in combination of two or more.

The content of the azole compound is preferably 0.1 to 20 parts by mass per 100 parts by mass of the (A) polyimide precursor, and more preferably 0.5 to 5 parts by mass from the viewpoint of photosensitivity characteristics. If the content of the azole compound per 100 parts by mass of the (A) polyimide precursor is 0.1 part by mass or more, discoloration of the copper or copper alloy surface is suppressed when the photosensitive resin composition of this embodiment is formed on copper or a copper alloy. On the other hand, if the content of the azole compound per 100 parts by mass of the (A) polyimide precursor is 20 parts by mass or less, excellent photosensitivity is achieved, which is preferred.

The photosensitive resin composition of this embodiment may contain an organotitanium compound for the purpose of improving elongation after a wet heat durability test.
There are no particular limitations on the organic titanium compounds that can be used, as long as an organic chemical substance is bonded to a titanium atom via a covalent bond or an ionic bond.

Specific examples of the organotitanium compound are shown below in I) to VII):
I) Titanium chelate compounds: Titanium chelate compounds having two or more alkoxy groups are preferred because they provide the photosensitive resin composition of this embodiment with good storage stability and can produce good patterns.
Specific examples include titanium bis(triethanolamine) diisopropoxide, titanium di(n-butoxide) bis(2,4-pentanedionate), titanium diisopropoxide bis(2,4-pentanedionate), titanium diisopropoxide bis(tetramethylheptanedionate), and titanium diisopropoxide bis(ethylacetoacetate).

II) Tetraalkoxytitanium compounds: For example, titanium tetra(n-butoxide), titanium tetraethoxide, titanium tetra(2-ethylhexoxide), titanium tetraisobutoxide, titanium tetraisopropoxide, titanium tetramethoxide, titanium tetramethoxypropoxide, titanium tetramethylphenoxide, titanium tetra(n-nonyloxide), titanium tetra(n-propoxide), titanium tetrastearyloxide, and titanium tetrakis[bis{2,2-(allyloxymethyl)butoxide}].

III) Titanocene compounds: For example, pentamethylcyclopentadienyltitanium trimethoxide, bis(η5-2,4-cyclopentadien-1-yl)bis(2,6-difluorophenyl)titanium, and bis(η5-2,4-cyclopentadien-1-yl)bis(2,6-difluoro-3-(1H-pyrrol-1-yl)phenyl)titanium.

IV) Monoalkoxytitanium compounds: For example, titanium tris(dioctylphosphate) isopropoxide and titanium tris(dodecylbenzenesulfonate) isopropoxide.

V) Titanium oxide compounds: For example, titanium oxide bis(pentanedionate), titanium oxide bis(tetramethylheptanedionate), phthalocyanine titanium oxide, etc.

VI) Titanium tetraacetylacetonate compounds: For example, titanium tetraacetylacetonate, etc.

VII) Titanate coupling agents: For example, isopropyl tridodecylbenzenesulfonyl titanate, etc.

Among the above I) to VII), it is preferred that the organotitanium compound is at least one compound selected from the group consisting of I) titanium chelate compounds, II) tetraalkoxytitanium compounds, and III) titanocene compounds, from the viewpoint of exhibiting better chemical resistance.
In particular, titanium diisopropoxide bis(ethylacetoacetate),
Titanium tetra(n-butoxide) and bis(η5-2,4-cyclopentadien-1-yl)bis(2,6-difluoro-3-(1H-pyrrol-1-yl)phenyl)titanium are preferred.

The content of these organotitanium compounds is preferably 0.01 to 10 parts by weight, and more preferably 0.1 to 2 parts by weight, per 100 parts by weight of the polyamic acid ester used as the polyimide precursor ((A). If the content is less than 0.01 part by weight, the desired adhesion will not be achieved, and if it exceeds 10 parts by weight, storage stability may be poor.

In the photosensitive resin composition of this embodiment, of the total solid content contained in the photosensitive resin composition, the total amount of components excluding (A) polyimide precursor is preferably 26% by mass or more and less than 60% by mass, relative to 100% by mass of (A) polyimide precursor. By including 26% by mass or more, the absolute value of the initial development time after the coating process and bake treatment can be shortened, leading to improved throughput in the semiconductor manufacturing process. Furthermore, by keeping the amount less than 60% by mass, the film properties can be maintained after a humidity and heat durability test.

<Method for producing cured relief pattern>
In this embodiment, the following steps (1) to (4):
(1) A step of applying the photosensitive resin composition of the above-described embodiment onto a substrate to form a photosensitive resin layer on the substrate;
(2) a step of exposing the photosensitive resin layer to light;
(3) developing the exposed photosensitive resin layer to form a relief pattern; and
(4) A method for producing a cured relief pattern can be provided, which includes a step of heat-treating the relief pattern to form a cured relief pattern.

Each step will be described below.
(1) Step of applying the photosensitive resin composition of the present embodiment onto a substrate to form a photosensitive resin layer on the substrate In this step, the photosensitive resin composition of the above-described embodiment is applied onto a substrate (in one aspect, a base material), and then dried as necessary to form a photosensitive resin layer.
As the application method, a method that has conventionally been used for applying a photosensitive resin composition, such as a method of applying using a spin coater, a bar coater, a blade coater, a curtain coater, a screen printing machine, or the like, or a method of spray application using a spray coater, can be used.

If necessary, the coating film made of the photosensitive resin composition of this embodiment can be dried, and examples of the drying method include air drying, heat drying in an oven or on a hot plate, and vacuum drying.
Furthermore, the coating film is desirably dried under conditions that do not cause imidization of the polyimide precursor (A) in the photosensitive resin composition of this embodiment.
Specifically, when air drying or heat drying is performed, drying can be carried out under conditions of 20°C to 140°C for 1 minute to 1 hour. Heating is preferably carried out at 100°C to 120°C for 230 to 250 seconds, and more preferably at 110°C for 240 seconds. A photosensitive resin layer can be formed on the substrate by the above steps.

(2) Step of exposing photosensitive resin layer In this step, the photosensitive resin layer formed in step (1) above is exposed to an ultraviolet light source or the like using an exposure device such as a contact aligner, a mirror projection, or a stepper, either directly or through a photomask or reticle having a pattern.

Thereafter, for the purpose of improving photosensitivity, etc., post-exposure baking (PEB) and/or pre-development baking may be carried out using any combination of temperature and time, as required.
The baking conditions are preferably in the range of a temperature of 40°C to 120°C and a time of 10 seconds to 240 seconds, but are not limited to these ranges as long as they do not impair the properties of the photosensitive resin composition of this embodiment.

(3) Step of Developing the Exposed Photosensitive Resin Layer to Form a Relief Pattern In this step, the unexposed portions of the exposed photosensitive resin layer are developed and removed.
As a developing method for developing the photosensitive resin layer after exposure (irradiation), any method can be selected from conventionally known photoresist developing methods, such as a rotary spray method, a puddle method, and an immersion method accompanied by ultrasonic treatment, etc. After development, post-development baking may be carried out at any combination of temperature and time, if necessary, for the purpose of adjusting the shape of the relief pattern, etc.

The developer used for development is preferably, for example, a good solvent for the photosensitive resin composition of this embodiment, or a combination of the good solvent and a poor solvent.
Preferred good solvents include, for example, N-methyl-2-pyrrolidone, N-cyclohexyl-2-pyrrolidone, N,N-dimethylacetamide, cyclopentanone, cyclohexanone, γ-butyrolactone, and α-acetyl-γ-butyrolactone.
Preferred examples of poor solvents include toluene, xylene, methanol, ethanol, isopropyl alcohol, ethyl lactate, propylene glycol monomethyl ether acetate, and water. When a good solvent and a poor solvent are used in combination, it is preferable to adjust the ratio of the poor solvent to the good solvent depending on the solubility of the polymer in the photosensitive resin composition of this embodiment. Furthermore, two or more types of each solvent, for example, several types, can be used in combination.

(4) Step of Heating the Relief Pattern to Form a Hardened Relief Pattern In this step, the relief pattern obtained by the above development is heated to dissolve the photosensitive component and also imidize the (A) polyimide precursor, thereby converting it into a hardened relief pattern consisting of a polyimide resin film.
Various methods can be selected for heat curing, such as using a hot plate, an oven, or a temperature-programmable heating oven. Heating can be carried out, for example, at 200°C to 400°C for 30 minutes to 5 hours. Air may be used as the atmospheric gas during heat curing, or an inert gas such as nitrogen or argon may also be used.

<Cured relief pattern>
The cured relief pattern of this embodiment includes a cured product of the photosensitive resin composition of this embodiment.

<Semiconductor Device>
The present embodiment also provides a semiconductor device including a cured relief pattern obtained by the above-described method for producing a cured relief pattern.
Therefore, a semiconductor device is provided that has a substrate that is a semiconductor element and a cured relief pattern of polyimide formed on the substrate by the above-described method for producing a cured relief pattern.
This embodiment can also be applied to a method for manufacturing a semiconductor device that uses a semiconductor element as a substrate and includes the above-described method for manufacturing a cured relief pattern as part of its steps. The semiconductor device of this embodiment can be manufactured by forming the cured relief pattern formed by the above-described method for manufacturing a cured relief pattern as a surface protective film, an interlayer insulating film, an insulating film for rewiring, a protective film for a flip-chip device, or a protective film for a semiconductor device having a bump structure, and combining this with a known method for manufacturing a semiconductor device.

<Display device>
In this embodiment, there is provided a display device including a display element and a cured film provided on the display element, the cured film having the above-described cured relief pattern. Here, the cured relief pattern may be laminated in direct contact with the display element or may be laminated with another layer sandwiched therebetween.
Examples of the cured film include surface protection films, insulating films, and planarizing films for TFT liquid crystal display elements and color filter elements, protrusions for MVA type liquid crystal display devices, and partition walls for cathodes in organic EL elements.

In addition to being applicable to the semiconductor devices described above, the photosensitive resin composition of this embodiment is also useful for applications such as interlayer insulation in multilayer circuits, cover coatings for flexible copper-clad boards, solder resist films, and liquid crystal alignment films.

Examples will be described below to clarify the effects of this embodiment, but the present embodiment is not limited to these examples.
In the examples, the following materials and measurement methods were used.

<Measurement and evaluation methods>
Evaluation of Resolution The photosensitive resin composition prepared as described below was spin-coated onto a 6-inch silicon wafer substrate using a spin coater (product name: D-Spin 60A, manufactured by SOKUDO Corporation) so that the film thickness after curing would be 5 mm, and the substrate was pre-baked at 110°C for 4 minutes.
The resulting coating film was exposed to I-rays at an exposure dose of 450 mJ/ ^cm2 using a stepper FP-3030iWa (Canon) with an exposure wavelength of I-rays (365 nm) through a test pattern reticle. Next, using a D-SPIN developer (Sokudo), rotary spray development was performed at 23°C using cyclopentanone as the developer for a time calculated by multiplying the time until the unexposed areas completely dissolved and disappeared by 1.4. This was followed by a rotary spray rinse with propylene glycol monomethyl ether acetate for 10 seconds, yielding a relief pattern consisting of a resin film. The film was then cured in a vertical curing oven VF200B (Koyo Thermo Systems) at 280°C for 2 hours under a nitrogen atmosphere, yielding a cured relief pattern.

The shape of each of the patterns obtained was observed using a scanning electron microscope (Hitachi High-Technogies S-4800) at an angle of 30°.
Regarding resolution, patterns having openings of different areas were formed in the same manner as above by exposure through a test patterned reticle, and the length of the opening side of the mask corresponding to the pattern having the smallest area and no residue at the bottom and a normal taper angle of the sidewall was defined as the minimum opening.
Furthermore, for the photosensitive resin compositions prepared in the examples and comparative examples, the resolution was evaluated as "A" if the minimum opening was 5 μm or less, "B" if the minimum opening was more than 5 μm and 7 μm or less, and "C" if the minimum opening was more than 7 μm.
If the evaluation is A or B, the photosensitive resin composition can be suitably used as the photosensitive resin composition of this embodiment.

Evaluation of Young's Modulus Each of the photosensitive resin compositions prepared in the Examples and Comparative Examples was applied by spin coating to a 6-inch silicon wafer substrate having an aluminum vapor deposition layer on its surface so that the film thickness after curing would be approximately 7 μm, and then dried.
A cured relief pattern (thermo-cured polyimide coating film) was obtained by heating the film at 280°C for 2 hours in a nitrogen atmosphere using a temperature-programmable curing oven (VF-2000, manufactured by Koyo Lindberg Co., Ltd.). The resulting polyimide coating film was cut into 3 mm wide strips using a dicing saw (DAD3350, manufactured by DISCO Corporation), and then peeled from the wafer using 10% by mass hydrochloric acid to obtain polyimide tape.
The Young's modulus (GPa) of the obtained polyimide tape was measured using a tensile tester (UTM-II-20 model, manufactured by Orientec Co., Ltd.) in accordance with ASTM D882-09.

- Aluminum adhesion evaluation (peel strength test)
The photosensitive resin compositions prepared in the examples and comparative examples were spin-coated onto a 6-inch silicon wafer substrate having an aluminum (Al) vapor-deposited layer on its surface so that the film thickness after curing would be 7 μm, and the coating was pre-baked at 110° C. for 4 minutes. Thereafter, a heat curing treatment was carried out at 280° C. for 2 hours in a nitrogen atmosphere using a vertical curing furnace (manufactured by Koyo Lindberg Co., Ltd., model name VF-2000B), to produce a wafer on which a polyimide resin film was formed.
The peel strength may be the peel strength between aluminum and a polyimide film measured according to the 180-degree peel method of JIS K6854-1 using a sample in which a polyimide film is formed on a substrate. The peel strength was measured under the following conditions.
Device name: RTG-1210 (manufactured by A&D Co., Ltd.)
Measurement temperature: room temperature Peeling speed: 50 mm/min
Atmosphere: Air Measurement sample width: 5 mm

The photosensitive resin composition was also evaluated for Al adhesion according to the following criteria.
A: Peel strength is 0.15 N/mm or more B+: Peel strength is 0.10 N/mm or more and less than 0.15 N/mm B-: Peel strength is 0.05 N/mm or more and less than 0.10 N/mm C: Peel strength is less than 0.05 N/mm If the evaluation is A, B+, or B-, it can be suitably used as the photosensitive resin composition of the present embodiment.

<Production Example I> (Synthesis of Polymer A: Polyimide Precursor)
18.61 g of 4,4'-oxydiphthalic dianhydride (ODPA) and 19.63 g of pyromellitic anhydride (PMDA) as acid anhydrides, and 40.61 g of 2-hydroxyethyl methacrylate (HEMA) as alcohols were placed in a 1-liter separable flask, and 102.58 g of γ-butyrolactone and 23.73 g of pyridine were added, followed by stirring at room temperature for 16 hours.

Next, the reaction mixture was cooled to 0° C. or below, and a solution of 60.98 g of dicyclohexylcarbodiimide (DCC) dissolved in 60.00 g of γ-butyrolactone was added thereto over 20 minutes with stirring.
Subsequently, while maintaining the reaction temperature at 2° C. or below, a solution prepared by dissolving 27.29 g of 2,2′-dimethyl-4,4′-diaminobiphenyl (m-TB) as a diamine in 80.00 g of γ-butyrolactone was added dropwise over 30 minutes.
The reaction mixture was then warmed to room temperature and stirred for a further 4 hours at room temperature, after which 13.66 g of ethanol was added as an end-capping agent and stirred for 30 minutes. The precipitate formed in the reaction mixture was removed by filtration to obtain a reaction mixture.

3 L of ethanol was added to the resulting reaction solution to produce a precipitate consisting of a crude polymer. The resulting crude polymer was filtered off and dissolved in 600 g of γ-butyrolactone to obtain a crude polymer solution. The resulting crude polymer solution was added dropwise to 6 L of water to precipitate the polymer. The resulting precipitate was filtered off and then vacuum-dried at 40°C for 72 hours to obtain a powdered polymer (polyimide precursor (polymer A)).

<Production Example II> (Synthesis of Polymer B: Polyimide Precursor)
15.51 g of 4,4'-oxydiphthalic dianhydride (ODPA) was placed in a 2 L separable flask, 13.12 g of 2-hydroxyethyl methacrylate (HEMA) as alcohols and 400 mL of γ-butyrolactone were added, and 8.15 g of pyridine was added while stirring at room temperature to obtain a reaction mixture. After the heat generation due to the reaction had ceased, the reaction mixture was allowed to cool to room temperature and stirred for 16 hours.
Next, under ice cooling, a solution of 20.63 g of dicyclohexylcarbodiimide (DCC) dissolved in 50 mL of γ-butyrolactone was added to the reaction mixture over 30 minutes with stirring, followed by the addition of a suspension of 9.30 g of 4,4'-oxydianiline (ODA) in 100 mL of γ-butyrolactone over 60 minutes with stirring. After further stirring at room temperature for 4 hours, 30 mL of ethyl alcohol was added and stirred for 30 minutes, followed by the addition of 400 mL of γ-butyrolactone. The precipitate formed in the reaction mixture was removed by filtration to obtain a reaction solution.

3 L of ethanol was added to the resulting reaction solution to produce a precipitate consisting of a crude polymer. The resulting crude polymer was filtered off and dissolved in 600 g of γ-butyrolactone to obtain a crude polymer solution. The resulting crude polymer solution was added dropwise to 6 L of water to precipitate the polymer. The resulting precipitate was filtered off and then vacuum-dried at 40°C for 72 hours to obtain a powdered polymer (polyimide precursor (polymer B)).

Example 1
(A) 10.00 g of Polymer A obtained in Production Example I,
(B) 0.50 g of 1-phenyl-2-[(benzoyloxy)imino]-1-propanone as a photoradical initiator,
(C) As the radical polymerizable compound,
(C-1) tetraethylene glycol dimethacrylate 1.40 g,
(C-2) Tris-(2-acryloxyethyl) isocyanurate 0.40 g,
(D) 0.30 g of 4-hydroxyisophthalic acid as compound,
(E) As a phenolic polymerization inhibitor, (E-1) 0.05 g of 1,3,5-tris(4-t-butyl-3-hydroxy-2,6-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione,
(E-2) 4-methoxyphenol 0.30 g,
0.50 g of N-phenyldiethanolamine as a sensitizer was dissolved in 18.49 g of γ-butyrolactone, and the solution was filtered through a microfilter with a pore size of 1 μm to prepare the photosensitive resin composition of Example 1. The composition was evaluated for resolution, Young's modulus, and aluminum adhesion according to the methods described above. The results are shown in Table 1.

Examples 2 to 6 and Comparative Examples 1 and 2
Photosensitive resin compositions were prepared in the same manner as in Example 1, except that the (A) polyimide precursor, (C) radical polymerizable compound, (D) compound, and (E) phenolic polymerization inhibitor in Example 1 were changed to those shown in Table 1, and the resolution, Young's modulus, and aluminum adhesion were evaluated. The evaluation results are shown in Table 1.

The polyimide obtained from the photosensitive resin composition of the example achieved a high Young's modulus, adhesion, and resolution compared to the photosensitive resin composition of the comparative example, and therefore exhibited good mechanical properties, good adhesion to metal electrodes, and high resolution.

The photosensitive resin composition of the present invention can be used to form insulating layers that exhibit excellent film properties when cured and good adhesion to metal electrodes, and can also stably open via patterns. This makes the composition suitable for use in the field of photosensitive materials, which are useful in the manufacture of electrical and electronic materials such as semiconductor devices and multilayer wiring boards.

Claims (11)

(A) The following general formula (1):
(wherein _X1 is a tetravalent organic group, _Y1 is a divalent organic group, m is an integer of 2 or more, and _R1 and _R2 each independently represent a hydrogen atom or a monovalent organic group),
(B) a photoradical initiator,
(D) the following general formula (2):
(wherein n is an integer of 0 to 2, l is an integer of 2 to 4, and _R3 is a functional group containing a heteroatom), and (E) a phenol-based polymerization inhibitor. The compound (D) is represented by the following general formula (3):
(wherein R4 _{, R5} , and _R6 each independently represent a hydrogen atom or a functional group containing a heteroatom, and at least one of R4 _{, R5} , and _R6 is a hydrogen atom). The photosensitive resin composition according to claim 1 or 2, wherein the functional group containing a heteroatom is an amino group, a hydroxy group, or a mercapto group. The photosensitive resin composition according to claim 1 or 2, wherein the (E) phenolic polymerization inhibitor includes 4-methoxyphenol. The photosensitive resin composition according to claim 1 or 2, further comprising (C) a radically polymerizable compound. The photosensitive resin composition according to claim 5, wherein the (C) radically polymerizable compound includes a compound having two radically polymerizable groups and a compound having three or more radically polymerizable groups. The Y ₁ is represented by the following general formula (5):
3. The photosensitive resin composition according to claim 1, wherein _R7 and _R8 each independently represent a hydrogen atom, a methyl group, a fluorine atom, or a trifluoromethyl group. The photosensitive resin composition according to claim 1 or 2, comprising two or more (E) phenolic polymerization inhibitors. (1) forming a photosensitive resin layer on a substrate by applying the photosensitive resin composition according to claim 1 or 2 onto the substrate;
(2) exposing the photosensitive resin layer to light;
(3) developing the exposed photosensitive resin layer to form a relief pattern;
(4) forming a hardened relief pattern by heat-treating the relief pattern;
1. A method for producing a cured relief pattern, comprising: A cured relief pattern comprising a cured product of the photosensitive resin composition according to claim 1 or 2. A semiconductor device comprising the cured relief pattern described in claim 10.