Photosensitive resin composition, method for producing patterned cured film, patterned cured film, and semiconductor element

Abstract

The present disclosure relates to: a photosensitive resin composition which contains (A) an alkali-soluble resin that has an imide bond and a phenolic hydroxyl group, and (B) a compound which generates an acid by means of light; a patterned cured film which is obtained using this photosensitive resin composition; a method for producing a patterned cured film; and a semiconductor element.

Description

[Technical Field]

[0001] The present invention relates to a photosensitive resin composition, a method for producing a patterned cured film, a patterned cured film, and a semiconductor device. [Background technology]

[0002] In recent years, with the increasing integration and miniaturization of semiconductor elements, surface protective layers and interlayer insulating layers of semiconductor elements are required to have heat resistance, mechanical properties, adhesion to metal copper wiring, etc. As materials for forming insulating layers having all of these properties, photosensitive resin compositions containing alkali-soluble resins have been developed (see, for example, Patent Documents 1 to 4). These photosensitive resin compositions are applied to a substrate and dried to form a resin film, which is then exposed to light and developed to obtain a patterned resin film (a patterned resin film). The patterned resin film is then heat-cured to form a patterned cured film (a patterned cured film), which can be used as a surface protective layer and an interlayer insulating layer. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2008-309885 [Patent Document 2] Japanese Patent Application Laid-Open No. 2007-57595 [Patent Document 3] Japanese Patent Application Laid-Open No. 2016-24306 [Patent Document 4] International Publication No. 2010 / 073948 Summary of the Invention [Problem to be solved by the invention]

[0004] The photosensitive resin composition used in the surface protective layer and the interlayer insulating layer is required to have excellent fine processability for increasing wiring density, low cure shrinkage for increasing multilayers, and mechanical strength for improving reliability.

[0005] An object of the present invention is to provide a photosensitive resin composition that has high resolution enabling fine processing and that can form a patterned cured film having low cure shrinkage and excellent mechanical strength. [Means for solving the problem]

[0006] One aspect of the present invention relates to a photosensitive resin composition containing (A) an alkali-soluble resin having an imide bond and a phenolic hydroxyl group, and (B) a compound that generates an acid when exposed to light.

[0007] Another aspect of the present invention relates to a method for producing a patterned cured film, comprising the steps of: applying the photosensitive resin composition to a part of or the entire surface of a substrate and drying the composition to form a resin film; exposing a part of or the entire surface of the resin film to light; developing the exposed resin film with an alkaline aqueous solution to form a patterned resin film; and heating the patterned resin film.

[0008] Another aspect of the present invention relates to a patterned cured film having a pattern, the pattern comprising a cured product of the photosensitive resin composition. Another aspect of the present invention further relates to a semiconductor device comprising the patterned cured film as an interlayer insulating layer or a surface protective layer. [Effects of the Invention]

[0009] According to the present invention, there is provided a photosensitive resin composition capable of forming a patterned cured film having high resolution enabling microfabrication, low cure shrinkage, and excellent mechanical strength. Furthermore, according to the present invention, there are provided a patterned cured film using the photosensitive resin composition, a method for producing the same, a semiconductor element, and an electronic device. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, embodiments of the present invention will be described in detail. However, the present invention is not limited to the following embodiments. In this specification, "(meth)acrylic acid" means "acrylic acid" or "methacrylic acid," and the same applies to other similar expressions such as (meth)acrylate. In this specification, "solid content" refers to the non-volatile content excluding volatile substances such as water and solvent contained in a photosensitive resin composition, and indicates components that remain without volatilization when the resin composition is dried, and also includes liquid, starch syrup-like, and wax-like substances at room temperature around 25°C.

[0011] In this specification, the term "process" includes not only an independent process but also a process that cannot be clearly distinguished from other processes as long as the intended function of the process is achieved. The term "layer" encompasses not only a structure that is formed over the entire surface when observed in a plan view, but also a structure that is formed only on a portion of the surface. Numerical ranges indicated using "to" indicate ranges that include the numerical values ​​before and after "to" as the minimum and maximum values, respectively. In numerical ranges described in stages in this specification, the upper or lower limit of a numerical range in one stage may be replaced with the upper or lower limit of a numerical range in another stage. In numerical ranges described in this specification, the upper or lower limit of the numerical range may be replaced with the values ​​shown in the examples.

[0012] [Photosensitive resin composition] The photosensitive resin composition according to one embodiment contains (A) an alkali-soluble resin having an imide bond and a phenolic hydroxyl group (hereinafter, sometimes referred to as "component (A)"), and (B) a compound that generates an acid upon exposure to light (hereinafter, sometimes referred to as "component (B)"). The photosensitive resin composition according to this embodiment can be suitably used as a positive-type photosensitive resin composition. The form of the positive-type photosensitive resin composition will be described in detail below.

[0013] <Component (A): Alkali-soluble resin> In this specification, the term "alkali-soluble resin" refers to a resin that is soluble in an alkaline aqueous solution (developer). The alkaline aqueous solution refers to an alkaline solution such as a tetramethylammonium hydroxide (TMAH) aqueous solution, a metal hydroxide aqueous solution, or an organic amine aqueous solution. A TMAH aqueous solution with a concentration of 2.38% by mass is generally used for development. The solubility of component (A) in an alkaline developer can be confirmed, for example, as follows.

[0014] A varnish obtained by dissolving a resin in a solvent is spin-coated onto a substrate such as a silicon wafer to form a coating film with a thickness of approximately 5 μm. This is then immersed in either an aqueous TMAH solution, an aqueous metal hydroxide solution, or an aqueous organic amine solution at 20 to 25°C. If the resulting coating film is uniformly soluble, the resin can be considered soluble in an alkaline developer.

[0015] The component (A) is a resin having a phenolic hydroxyl group from the viewpoints of solubility in an alkaline aqueous solution, high resolution, and low cure shrinkage, and having an imide bond from the viewpoint of mechanical strength.

[0016] The phenolic hydroxyl group in component (A) may have a structure derived from phenol, o-cresol, m-cresol, or p-cresol. The imide bond in component (A) may be bonded to an aromatic ring.

[0017] The component (A) may be a resin having a bisphenolimide skeleton. The bisphenolimide skeleton may be a structure based on the reaction between a tetracarboxylic dianhydride and an aminophenol compound.

[0018] The component (A) may have, as a bisphenolimide skeleton, a structure derived from at least one selected from the group consisting of compounds represented by the following formula (I), compounds represented by the following formula (II), and compounds represented by the following formula (III), in order to further reduce cure shrinkage and further increase mechanical strength. [ka]

[0019] In the formula, R 1 , R 2 , R 3 , R 4 , R 5 , and R 6 each independently represents a hydrogen atom or a methyl group, and R a and R b each independently represents an ether bond, a thioether bond, a carbonyl group, an alkylene group having 1 to 3 carbon atoms, or a single bond. Examples of the alkylene group having 1 to 3 carbon atoms include a methylene group, an ethylene group, an ethylidene group, a propylene group, a propylidene group, and an isopropylidene group.

[0020] In the compound represented by formula (I), (II), or (III), from the viewpoint of increasing solubility, it is preferable that at least one of the hydroxyl groups represented by OH is bonded to the meta position or ortho position of the imide group (imide bond).

[0021] The component (A) may contain a resin having, as a bisphenolimide skeleton, a structural unit derived from a compound represented by the following formula (1), (2), (3), (4), (5), or (6), because this has an excellent balance between solubility and mechanical strength. [ka]

[0022] R in formula (4) and formula (5) a is R in formula (II) a and R in formula (6) b is R in formula (III) b From the viewpoint of increasing solubility, R a is preferably an ether bond or a carbonyl group, and R b is preferably an isopropylidene group.

[0023] Component (A) may further have structural units derived from cresol compounds such as o-cresol, m-cresol, and p-cresol, and may further have structural units derived from formaldehyde, bis(methoxymethyl)biphenyl, or dimethoxymethylbenzene.

[0024] Component (A) can be synthesized, for example, according to a typical synthesis method for phenol novolac resins. Component (A) may be a reaction product of a bisphenolimide compound and a cresol compound, or a reaction product of a bisphenolimide compound, a cresol compound, and formaldehyde, bis(methoxymethyl)biphenyl, or dimethoxymethylbenzene. Component (A) may have a structure represented by the following formula, for example:

[0025] [ka] [ka]

[0026] Considering the balance between solubility in an alkaline aqueous solution, photosensitive properties, and mechanical strength of the cured film, the weight-average molecular weight (Mw) of component (A) may be 1,000 to 50,000, 2,000 to 45,000, 3,000 to 42,000, 5,000 to 40,000, 10,000 to 40,000, or 15,000 to 38,000. Mw is a value obtained by measuring by gel permeation chromatography (GPC) and converting from a standard polystyrene calibration curve.

[0027] <Component (B): Compound that generates acid when exposed to light> Component (B), a compound that generates an acid when exposed to light (when exposed to light), functions as a photosensitizer in the photosensitive resin composition. Component (B) generates an acid when exposed to light, thereby increasing the solubility of the exposed area in an alkaline aqueous solution. Compounds generally referred to as photoacid generators can be used as component (B). Examples of component (B) include o-quinonediazide compounds, aryldiazonium salts, diaryliodonium salts, and triarylsulfonium salts. Component (B) may consist of only one of these compounds, or may contain two or more of them. Among these, component (B) may be an o-quinonediazide compound due to its high sensitivity.

[0028] As the o-quinone diazide compound, for example, a compound obtained by subjecting o-quinone diazide sulfonyl chloride to a condensation reaction with a hydroxy compound and / or an amino compound in the presence of a dehydrochlorinating agent can be used.

[0029] Examples of o-quinone diazide sulfonyl chlorides include benzoquinone-1,2-diazide-4-sulfonyl chloride, naphthoquinone-1,2-diazide-5-sulfonyl chloride, and naphthoquinone-1,2-diazide-6-sulfonyl chloride.

[0030] Examples of hydroxy compounds include hydroquinone, resorcinol, pyrogallol, bisphenol A, bis(4-hydroxyphenyl)methane, 1,1-bis(4-hydroxyphenyl)-1-[4-{1-(4-hydroxyphenyl)-1-methylethyl}phenyl]ethane, 2,2-bis(4-hydroxyphenyl)hexafluoropropane, 2,3,4-trihydroxybenzophenone, 2,3,4,4'-tetrahydroxybenzophenone, and 2,2',4,4'-tetrahydroxybenzophenone. benzophenone, 2,3,4,2',3'-pentahydroxybenzophenone, 2,3,4,3',4',5'-hexahydroxybenzophenone, bis(2,3,4-trihydroxyphenyl)methane, bis(2,3,4-trihydroxyphenyl)propane, 4b,5,9b,10-tetrahydro-1,3,6,8-tetrahydroxy-5,10-dimethylindeno[2,1-a]indene, tris(4-hydroxyphenyl)methane, and tris(4-hydroxyphenyl)ethane.

[0031] Examples of the amino compound include p-phenylenediamine, m-phenylenediamine, 4,4'-diaminodiphenyl ether, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl sulfide, o-aminophenol, m-aminophenol, p-aminophenol, 3,3'-diamino-4,4'-dihydroxybiphenyl, 4,4'-diamino-3,3'-dihydroxybiphenyl, bis(3-amino-4-hydroxyphenyl)propane, bis(4-amino-3-hydroxyphenyl)propane, bis(3-amino-4-hydroxyphenyl)sulfone, bis(4-amino-3-hydroxyphenyl)sulfone, bis(3-amino-4-hydroxyphenyl)hexafluoropropane, and bis(4-amino-3-hydroxyphenyl)hexafluoropropane.

[0032] Among these, from the viewpoint of reactivity during synthesis of the o-quinonediazide compound and an appropriate absorption wavelength range during exposure of the resin film, a condensation product of 1,1-bis(4-hydroxyphenyl)-1-[4-{1-(4-hydroxyphenyl)-1-methylethyl}phenyl]ethane and 1-naphthoquinone-2-diazide-5-sulfonyl chloride, or a condensation product of tris(4-hydroxyphenyl)methane or tris(4-hydroxyphenyl)ethane and 1-naphthoquinone-2-diazide-5-sulfonyl chloride may be used.

[0033] Examples of the dehydrochlorinating agent include sodium carbonate, sodium hydroxide, sodium bicarbonate, potassium carbonate, potassium hydroxide, trimethylamine, triethylamine, and pyridine.

[0034] The o-quinone diazide sulfonyl chloride and the hydroxy compound and / or amino compound are preferably mixed so that the total number of moles of hydroxy groups and amino groups is 0.5 to 1 mole per mole of o-quinone diazide sulfonyl chloride. The preferred mixing ratio of the dehydrochlorinating agent to o-quinone diazide sulfonyl chloride is in the range of 0.95 / 1 mole equivalent to 1 / 0.95 mole equivalent.

[0035] The preferred reaction temperature for the above reaction is 0 to 40° C., and the preferred reaction time is 1 to 10 hours. As the reaction solvent, for example, dioxane, acetone, methyl ethyl ketone, tetrahydrofuran, diethyl ether, or N-methylpyrrolidone is used.

[0036] The content of the (B) component may be 1 to 50 parts by mass, 3 to 35 parts by mass, or 5 to 20 parts by mass per 100 parts by mass of the (A) component, since this increases the difference in dissolution rate between the exposed and unexposed areas and improves sensitivity.

[0037] <Component (C): Thermal crosslinking agent> The photosensitive resin composition of this embodiment may further contain a thermal crosslinking agent as component (D). Component (C) is a compound having a structure that can react with component (A) to form a crosslinked structure when the patterned resin film is heated and cured. This prevents the film from becoming brittle and melting. Examples of component (C) include compounds having a phenolic hydroxyl group, compounds having an alkoxy group, and compounds having an epoxy group.

[0038] The "compound having a phenolic hydroxyl group" referred to here does not include component (A). The compound having a phenolic hydroxyl group as a thermal crosslinker not only functions as a thermal crosslinker but also increases the dissolution rate of the exposed area during development in an alkaline aqueous solution, thereby improving sensitivity. The Mw of such a compound having a phenolic hydroxyl group may be 3000 or less, 2000 or less, or 1500 or less, taking into consideration the balance between solubility in an alkaline aqueous solution, photosensitive properties, and mechanical strength.

[0039] As the compound having an alkoxy group, a conventionally known compound can be used. The compound having an alkoxy group may have a methoxy group, or may have four or more methoxy groups, since it can impart high reactivity and heat resistance. The compound having an alkoxy group has an excellent balance between the effect of promoting dissolution of the exposed area and the mechanical strength of the cured film, so it may be a compound selected from the compounds represented by the following formula:

[0040] [ka]

[0041] The compound having an epoxy group may be a conventionally known compound, such as a bisphenol A epoxy compound, a bisphenol F epoxy compound, a phenol novolac epoxy compound, a cresol novolac epoxy compound, an alicyclic epoxy compound, a glycidylamine epoxy compound, a heterocyclic epoxy compound, a halogenated epoxy compound, and a polyalkylene glycol diglycidyl ether.

[0042] In addition to the compounds described above, the component (C) may also be, for example, an aromatic compound having a hydroxymethyl group, such as bis[3,4-bis(hydroxymethyl)phenyl]ether or 1,3,5-tris(1-hydroxy-1-methylethyl)benzene; a compound having a maleimide group, such as bis(4-maleimidophenyl)methane or 2,2-bis[4-(4'-maleimidophenoxy)phenyl]propane; a compound having a norbornene skeleton; a polyfunctional acrylate compound; a compound having an oxetanyl group; a compound having a vinyl group; or a blocked isocyanate compound.

[0043] The content of the component (C) may be 1 to 70 parts by mass, 2 to 50 parts by mass, or 3 to 40 parts by mass per 100 parts by mass of the component (A), from the viewpoints of the heat resistance of the cured film and warping of the coated substrate.

[0044] <Component (D): Elastomer> The resin composition of this embodiment may further contain an elastomer as component (D) to improve the flexibility of the patterned cured film. Examples of component (D) include styrene-based elastomers, olefin-based elastomers, urethane-based elastomers, polyester-based elastomers, polyamide-based elastomers, acrylic elastomers, and silicone-based elastomers. These may be used alone or in combination of two or more. The skeleton of an elastomer component may also be introduced into component (A).

[0045] The acrylic elastomer may have a structural unit represented by the following formula (8): By having the structural unit represented by the following formula (8), the acrylic elastomer has improved compatibility between the (A) component and the (D) component, which sufficiently suppresses clouding of the photosensitive resin composition, reduces the haze value of the patterned cured film, and further improves the mechanical strength. [ka]

[0046] In formula (8), R 17 represents a hydrogen atom or a methyl group, and R 18 represents a hydroxyalkyl group having 2 to 20 carbon atoms.

[0047] R 18 Examples of the hydroxyalkyl group having 2 to 20 carbon atoms and represented by the formula (I) include a hydroxyethyl group, a hydroxypropyl group, a hydroxybutyl group, a hydroxypentyl group, a hydroxyhexyl group, a hydroxyheptyl group, a hydroxyoctyl group, a hydroxynonyl group, a hydroxydecyl group, a hydroxyundecyl group, a hydroxydodecyl group (sometimes referred to as a hydroxylauryl group), a hydroxytridecyl group, a hydroxytetradecyl group, a hydroxypentadecyl group, a hydroxyhexadecyl group, a hydroxyheptadecyl group, a hydroxyoctadecyl group, a hydroxynonadecyl group, and a hydroxyeicosyl group. These groups may be linear or branched.

[0048] In formula (8), R is preferably used in order to further improve compatibility with component (A) and mechanical strength. 18 is preferably a hydroxyalkyl group having 2 to 15 carbon atoms, more preferably a hydroxyalkyl group having 2 to 10 carbon atoms, and further preferably a hydroxyalkyl group having 2 to 8 carbon atoms.

[0049] Examples of monomers that provide the structural unit represented by formula (8) include hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, hydroxybutyl (meth)acrylate, hydroxypentyl (meth)acrylate, hydroxyhexyl (meth)acrylate, hydroxyheptyl (meth)acrylate, hydroxyoctyl (meth)acrylate, hydroxynonyl (meth)acrylate, hydroxydecyl (meth)acrylate, hydroxyundecyl (meth)acrylate, hydroxydodecyl (meth)acrylate (sometimes referred to as hydroxylauryl (meth)acrylate), hydroxytridecyl (meth)acrylate, hydroxytetradecyl (meth)acrylate, hydroxypentadecyl (meth)acrylate, hydroxyhexadecyl (meth)acrylate, hydroxyheptadecyl (meth)acrylate, hydroxyoctadecyl (meth)acrylate, hydroxynonadecyl (meth)acrylate, and hydroxyeicosyl (meth)acrylate. These monomers may be used alone or in combination of two or more.

[0050] Among these, from the viewpoints of further improving compatibility with component (A) and the elongation at break of the cured film, it is preferable to use hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, hydroxybutyl (meth)acrylate, hydroxypentyl (meth)acrylate, hydroxyhexyl (meth)acrylate, hydroxyheptyl (meth)acrylate, hydroxyoctyl (meth)acrylate, hydroxynonyl (meth)acrylate, hydroxydecyl (meth)acrylate, hydroxyundecyl (meth)acrylate, or hydroxydodecyl (meth)acrylate.

[0051] The component (D) may be an acrylic elastomer consisting solely of the structural unit represented by formula (8), or may be an acrylic elastomer having structural units other than the structural unit represented by formula (8). When the acrylic resin has structural units other than the structural unit represented by formula (8), the proportion of the structural unit represented by formula (8) in the acrylic resin may be 0.1 to 30 mol%, 0.3 to 20 mol%, or 0.5 to 10 mol% relative to the total amount of the component (D).

[0052] The acrylic elastomer may further have a structural unit represented by the following formula (9). [ka]

[0053] In formula (9), R 19 represents a hydrogen atom or a methyl group, and R 20 represents a monovalent organic group having a primary, secondary, or tertiary amino group. When component (D) has a structural unit represented by formula (9), it is possible to further improve the ability to inhibit dissolution of unexposed areas in a developer and the adhesion to metal substrates.

[0054] Examples of monomers that give acrylic elastomers having a structural unit represented by formula (9) include aminoethyl (meth)acrylate, N-methylaminoethyl (meth)acrylate, N,N-dimethylaminoethyl (meth)acrylate, N-ethylaminoethyl (meth)acrylate, N,N-diethylaminoethyl (meth)acrylate, aminopropyl (meth)acrylate, N-methylaminopropyl (meth)acrylate, N,N-dimethylaminopropyl (meth)acrylate, N-ethyl methylaminopropyl (meth)acrylate, N,N-diethylaminopropyl (meth)acrylate, piperidin-4-yl (meth)acrylate, 1-methylpiperidin-4-yl (meth)acrylate, 2,2,6,6-tetramethylpiperidin-4-yl (meth)acrylate, 1,2,2,6,6-pentamethylpiperidin-4-yl (meth)acrylate, (piperidin-4-yl)methyl (meth)acrylate, and 2-(piperidin-4-yl)ethyl (meth)acrylate. These monomers can be used alone or in combination of two or more.

[0055] Among these, from the viewpoint of further improving the adhesion of the patterned cured film to the substrate and the compatibility with component (A), R 20 is preferably a monovalent organic group represented by the following formula (10). [ka]

[0056] In formula (10), Y represents an alkylene group having 1 to 5 carbon atoms, and R 21 , R 22 , R 23 , R 25 , and R 25 each independently represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms; and e represents an integer of 0 to 10.

[0057] In formula (9), R 20Examples of monomers that provide a structural unit represented by a monovalent organic group represented by formula (10) include piperidin-4-yl(meth)acrylate, 1-methylpiperidin-4-yl(meth)acrylate, 2,2,6,6-tetramethylpiperidin-4-yl(meth)acrylate, 1,2,2,6,6-pentamethylpiperidin-4-yl(meth)acrylate, (piperidin-4-yl)methyl(meth)acrylate, and 2-(piperidin-4-yl)ethyl(meth)acrylate. Among these, 1,2,2,6,6-pentamethylpiperidin-4-yl methacrylate is commercially available as FA-711MM, and 2,2,6,6-tetramethylpiperidin-4-yl methacrylate is commercially available as FA-712HM (both manufactured by Showa Denko Materials Co., Ltd. (formerly Hitachi Chemical Co., Ltd.)), which are preferred because they are commercially available.

[0058] When the component (D) has a structural unit represented by formula (10), the proportion of the structural unit represented by formula (9) is preferably 0.3 to 10 mol %, more preferably 0.4 to 6 mol %, and even more preferably 0.5 to 5 mol %, relative to the total amount of the component (D), from the viewpoints of compatibility with the component (A) and solubility in the developer.

[0059] The acrylic elastomer may further have a structural unit represented by the following formula (11): When the acrylic elastomer has a structural unit represented by formula (11), the thermal shock resistance of the cured film can be further improved. [ka]

[0060] In formula (11), R 26 represents a hydrogen atom or a methyl group, and R 27 represents an alkyl group having 4 to 20 carbon atoms.

[0061] R 27Examples of the alkyl group having 4 to 20 carbon atoms include a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, an undecyl group, a dodecyl group (sometimes called a lauryl group), a tridecyl group, a tetradecyl group, a pentadecyl group, a hexadecyl group, a heptadecyl group, an octadecyl group, a nonadecyl group, and an eicosyl group. These groups may be linear or branched.

[0062] In formula (11), from the viewpoint of alkali solubility, thermal shock resistance, and compatibility with component (A), R 27 is preferably an alkyl group having 4 to 16 carbon atoms, more preferably an alkyl group having 4 to 12 carbon atoms, and even more preferably an alkyl group having 4 carbon atoms (n-butyl group).

[0063] Examples of the monomer represented by formula (11) include butyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, octyl (meth)acrylate, nonyl (meth)acrylate, decyl (meth)acrylate, undecyl (meth)acrylate, dodecyl (meth)acrylate (sometimes referred to as lauryl (meth)acrylate), tridecyl (meth)acrylate, tetradecyl (meth)acrylate, pentadecyl (meth)acrylate, hexadecyl (meth)acrylate, heptadecyl (meth)acrylate, octadecyl (meth)acrylate, nonadecyl (meth)acrylate, and eicosyl (meth)acrylate. These monomers may be used alone or in combination of two or more.

[0064] Among these, from the viewpoint of further improving the elongation at break and further reducing the modulus of elasticity, it is preferable to use butyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, octyl (meth)acrylate, nonyl (meth)acrylate, decyl (meth)acrylate, undecyl (meth)acrylate, or dodecyl (meth)acrylate (also referred to as lauryl (meth)acrylate).

[0065] When component (D) has a structural unit represented by formula (11), the proportion of the structural unit represented by formula (11) is preferably 50 to 93 mol%, more preferably 55 to 85 mol%, and even more preferably 60 to 80 mol%, based on the total amount of component (D). By having the proportion of the structural unit represented by formula (11) be 50 to 93 mol%, the thermal shock resistance of the cured film can be further improved.

[0066] The acrylic elastomer may further have a structural unit represented by the following formula (12): When the acrylic elastomer has a structural unit represented by formula (12), the alkali solubility of the exposed portion of the resin film can be further improved. [ka]

[0067] In formula (12), R 28 represents a hydrogen atom or a methyl group.

[0068] Examples of monomers that provide the structural unit represented by formula (12) include acrylic acid and methacrylic acid.

[0069] When component (D) has a structural unit represented by formula (12), the proportion of the structural unit represented by formula (12) is preferably 5 to 35 mol %, more preferably 10 to 30 mol %, and even more preferably 15 to 25 mol %, relative to the total amount of component (D). By having the composition ratio of the structural unit represented by formula (12) be 5 to 35 mol %, compatibility with component (A) and alkali solubility of exposed areas can be further improved.

[0070] The acrylic elastomer can be obtained, for example, by blending a monomer that provides the structural unit represented by the above formula (8) and a monomer that provides the structural unit represented by formula (9), (11), or (12), which is added as needed, and stirring the mixture in a solvent such as ethyl lactate, toluene, or isopropanol, and heating it as needed.

[0071] The monomers used in the synthesis of the acrylic elastomer may further contain monomers other than those that provide the structural units represented by the formulae (8), (9), (11), and (12).

[0072] Examples of such monomers include N-(meth)acryloyloxyethylhexahydrophthalimide, 1,4-cyclohexanedimethanol mono(meth)acrylate, benzyl (meth)acrylate, 4-methylbenzyl (meth)acrylate, acrylonitrile, esters of vinyl alcohol such as vinyl-n-butyl ether, tetrahydrofurfuryl (meth)acrylate, glycidyl (meth)acrylate, 2,2,2-trifluoroethyl (meth)acrylate, 2,2,3,3-tetrafluoropropyl (meth)acrylate, α-bromo(meth)acrylic acid, α-chloro(meth)acrylic acid, β-furyl(meth)acrylic acid, β-styryl(meth)acrylic acid, maleic acid, maleic anhydride, maleic acid monoesters such as monomethyl maleate, monoethyl maleate, and monoisopropyl maleate, fumaric acid, cinnamic acid, α-cyanocinnamic acid, itaconic acid, crotonic acid, and propiolic acid. These monomers may be used alone or in combination of two or more.

[0073] The Mw of component (D) may be 2,000 to 100,000, 3,000 to 60,000, 5,000 to 50,000, or 10,000 to 40,000. An Mw of 2,000 or more can improve the thermal shock resistance of the cured film, while an Mw of 100,000 or less can improve compatibility with component (A) and developability. Here, Mw is a value measured by gel permeation chromatography (GPC) and converted from a standard polystyrene calibration curve.

[0074] The content of component (D) may be 1 to 50 parts by mass, 2 to 30 parts by mass, or 3 to 20 parts by mass per 100 parts by mass of component (A), from the viewpoint of the balance between the alkali solubility of the exposed area, the alkali dissolution inhibition of the unexposed area, the adhesion to the metal substrate, and the thermal shock resistance.

[0075] <Component (E): Adhesion aid> The photosensitive resin composition of this embodiment may contain an adhesion promoter as component (E). By containing component (E), it is possible to provide a photosensitive resin composition that gives a patterned cured film with good adhesion to the substrate. Component (E) may contain a nitrogen-containing aromatic compound represented by the following formula (7): [ka]

[0076] In formula (7), R 51 represents a hydrogen atom or a hydrocarbon group, and R 52 represents a hydrogen atom, an amino group, or a phenyl group. A and B each independently represent a nitrogen atom, or a carbon atom and a hydrogen atom (CH) bonded thereto.

[0077] The nitrogen-containing aromatic compound represented by formula (7) may be a nitrogen-containing aromatic compound represented by the following formula (7a) from the viewpoint of further improving adhesion to a substrate. 52 is R in equation (7). 52 is synonymous with. [ka]

[0078] Examples of the component (E) include 1H-tetrazole, 5-aminotetrazole, 5-phenyltetrazole, and 5-methyltetrazole. Among these, the component (E) may contain 1H-tetrazole or 5-aminotetrazole from the viewpoint of providing better adhesion to the substrate.

[0079] The amount of component (E) added may be 0.01 to 20 parts by mass, 0.015 to 10 parts by mass, or 0.02 to 7 parts by mass per 100 parts by mass of component (A), from the viewpoint of imparting good adhesion to the substrate and good sensitivity.

[0080] <Other ingredients> The photosensitive resin composition of the present embodiment may contain, in addition to the above components (A) to (E), components such as a solvent, a compound that generates an acid upon heating, a dissolution promoter, a dissolution inhibitor, a coupling agent, and a surfactant or a leveling agent.

[0081] (solvent) The photosensitive resin composition of this embodiment contains a solvent, which facilitates application to a substrate and allows the formation of a coating film of uniform thickness. Examples of solvents include γ-butyrolactone, ethyl lactate, propylene glycol monomethyl ether acetate, benzyl acetate, n-butyl acetate, ethoxyethyl propionate, 3-methylmethoxypropionate, N-methyl-2-pyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, hexamethylphosphorylamide, tetramethylene sulfone, diethyl ketone, diisobutyl ketone, methyl amyl ketone, cyclohexanone, propylene glycol monomethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, and dipropylene glycol monomethyl ether. The solvents may be used alone or in combination. Among these, ethyl lactate or γ-butyrolactone is preferred from the viewpoints of solubility and uniformity of the coating film.

[0082] (Compounds that produce acids when heated) The use of a compound that generates an acid upon heating makes it possible to generate an acid when the patterned resin film is heated, accelerating the reaction between component (A) and component (C), i.e., the thermal crosslinking reaction, and improving the heat resistance of the patterned cured film. Furthermore, the compound that generates an acid upon heating also generates an acid upon light irradiation, increasing the solubility of the exposed area in an alkaline aqueous solution. This further increases the difference in solubility in an alkaline aqueous solution between the unexposed and exposed areas, further improving resolution.

[0083] The compound that generates an acid upon heating is preferably one that generates an acid upon heating to, for example, 50 to 250°C. Examples of the compound that generates an acid upon heating include salts formed from a strong acid and a base, such as onium salts, and imide sulfonates. When a compound that generates an acid upon heating is used, the content may be 0.1 to 30 parts by mass, 0.2 to 20 parts by mass, or 0.5 to 10 parts by mass per 100 parts by mass of component (A).

[0084] (solubility enhancer) By incorporating a dissolution promoter into the positive photosensitive resin composition, the dissolution rate of the exposed area during development with an alkaline aqueous solution can be increased, thereby improving sensitivity and resolution. Conventional dissolution promoters can be used. Examples of dissolution promoters include compounds having a carboxy group, a sulfo group, or a sulfonamide group. When a dissolution promoter is used, its content can be determined based on the dissolution rate in the alkaline aqueous solution, and can be, for example, 0.01 to 30 parts by mass per 100 parts by mass of component (A).

[0085] (dissolution inhibitors) Dissolution inhibitors are compounds that inhibit the solubility of component (A) in an alkaline aqueous solution and are used to control the remaining film thickness, development time, and contrast. Examples of dissolution inhibitors include diphenyliodonium nitrate, bis(p-tert-butylphenyl)iodonium nitrate, diphenyliodonium bromide, diphenyliodonium chloride, and diphenyliodonium iodide. When a dissolution inhibitor is used, its content may be 0.01 to 20 parts by mass, 0.01 to 15 parts by mass, or 0.05 to 10 parts by mass per 100 parts by mass of component (A), taking into account the allowable range of sensitivity and development time.

[0086] (coupling agent) By incorporating a coupling agent into the photosensitive resin composition, the adhesiveness of the patterned cured film formed to the substrate can be further improved. Examples of coupling agents include organosilane compounds and aluminum chelate compounds. Examples of organosilane compounds include KBM-403, KBM-803, and KBM-903 (trade names, manufactured by Shin-Etsu Chemical Co., Ltd.). When a coupling agent is used, the content may be 0.1 to 20 parts by mass or 0.5 to 10 parts by mass per 100 parts by mass of component (A).

[0087] (Surfactant or leveling agent) By incorporating a surfactant or leveling agent into the photosensitive resin composition, the coatability can be further improved. Specifically, for example, by including a surfactant or leveling agent, striations (uneven film thickness) can be more effectively prevented and developability can be further improved. Examples of such surfactants or leveling agents include polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, and polyoxyethylene octylphenol ether. Examples of commercially available products include Megafac F-171, F-565, and RS-78 (trade names, manufactured by DIC Corporation).

[0088] When a surfactant or leveling agent is used, the content thereof may be 0.001 to 5 parts by mass or 0.01 to 3 parts by mass per 100 parts by mass of the component (A).

[0089] The photosensitive resin composition of this embodiment can be developed using an aqueous alkaline solution such as tetramethylammonium hydroxide (TMAH).

[0090] [Patterned cured film and method for producing the patterned cured film] A patterned cured film according to one embodiment has a pattern, and the pattern comprises a cured product of the photosensitive resin composition described above. The patterned cured film is obtained by heating the photosensitive resin composition described above. A method for producing the patterned cured film will be described below.

[0091] The method for producing a patterned cured film according to this embodiment includes a step of applying the above-described photosensitive resin composition to a part or the entire surface of a substrate and drying the composition to form a resin film (a coating / drying (film-forming) step), a step of exposing a part or the entire surface of the resin film to light (an exposure step), a step of developing the exposed resin film with an alkaline aqueous solution to form a patterned resin film (a development step), and a step of heating the patterned resin film (a heat treatment step). Each step will be described below.

[0092] (Coating and drying (film formation) process) First, the photosensitive resin composition of this embodiment is applied to a substrate and dried to form a resin film. In this process, the photosensitive resin composition of this embodiment is spin-coated using a spinner or the like onto a substrate such as a glass substrate, semiconductor, metal oxide insulator (e.g., TiO2, SiO2), or silicon nitride to form a coating film. The thickness of the coating film is not particularly limited, but may be 0.1 to 40 μm. The substrate on which this coating film has been formed is then dried using a hot plate, oven, or the like. The drying temperature and drying time are not particularly limited, but may be 80 to 140°C for 1 to 7 minutes. This forms a resin film on the substrate. The thickness of the resin film is not particularly limited, but may be 0.1 to 40 μm.

[0093] (Exposure process) Next, in the exposure step, the resin film formed on the substrate is irradiated through a mask with actinic rays such as ultraviolet light, visible light, or radioactive rays. In the photosensitive resin composition of this embodiment, component (A) has high transparency to g-, h-, and i-rays, so any or all of g-, h-, and i-rays can be used for irradiation.

[0094] (Development process) In the development step, the exposed portions of the resin film after the exposure step are removed with a developer, thereby patterning the resin film and obtaining a patterned resin film. Suitable developers include aqueous alkaline solutions such as sodium carbonate, sodium hydroxide, potassium hydroxide, sodium silicate, ammonia, ethylamine, diethylamine, triethylamine, triethanolamine, and tetramethylammonium hydroxide (TMAH). The base concentration of these aqueous solutions may be 0.1 to 10% by mass. Alcohols or surfactants may also be added to the developer. These may be blended in amounts of 0.01 to 10 parts by mass or 0.1 to 5 parts by mass, respectively, per 100 parts by mass of the developer. When developing using a developer, the developer is applied to the resin film by, for example, shower development, spray development, immersion development, or puddle development, and then allowed to stand at 18 to 40°C for 30 to 360 seconds. After standing, the patterned resin film is washed with water and spin-dried to remove the residue.

[0095] (heat treatment process) Next, in the heat treatment step, the patterned resin film is heat-treated to form a patterned cured film. The heating temperature in the heat treatment step may be 300°C or less, 270°C or less, or 250°C or less, in order to sufficiently prevent thermal damage to the semiconductor device.

[0096] The heat treatment can be performed using an oven such as a quartz tube furnace, a hot plate, a rapid thermal annealer, a vertical diffusion furnace, an infrared curing oven, an electron beam curing oven, or a microwave curing oven. While either air or an inert atmosphere such as nitrogen can be selected, nitrogen is preferable because it can prevent oxidation of the pattern. The above-mentioned heating temperature range is lower than conventional heating temperatures, minimizing damage to the support substrate and semiconductor device. Therefore, by using the method for producing a patterned cured film according to this embodiment, electronic devices can be produced with a high yield. This also leads to energy savings in the process. Furthermore, the positive photosensitive resin composition according to this embodiment exhibits small volume shrinkage (curing shrinkage) during the heat treatment process, which is common in photosensitive polyimides and the like, and therefore prevents a decrease in dimensional accuracy.

[0097] The heat treatment time in the heat treatment step may be any time long enough to cure the positive photosensitive resin composition, but is preferably about 5 hours or less in terms of work efficiency.

[0098] The heat treatment can be performed using a microwave curing device or a variable frequency microwave curing device, in addition to the oven described above. By using these devices, it is possible to effectively heat only the resin film while maintaining the temperature of the substrate and the semiconductor device at a desired temperature (for example, 200°C or less) (see J. Photopolym. Sci. Technol., 18, 327-332 (2005)).

[0099] The patterned cured film according to this embodiment can be used as an interlayer insulating layer or a surface protective layer of a semiconductor element. A semiconductor element having an interlayer insulating layer or a surface protective layer formed from a cured film of the above-described photosensitive resin composition, and an electronic device including the semiconductor element can be produced. The semiconductor element may be, for example, a memory, a package, or the like having a multilayer wiring structure, a rewiring structure, or the like. Examples of electronic devices include mobile phones, smartphones, tablet terminals, personal computers, and hard disk suspensions. By providing a patterned cured film formed from the photosensitive resin composition of this embodiment, semiconductor elements and electronic devices with excellent reliability can be provided. [Example]

[0100] The present invention will be specifically described below based on examples, but the present invention is not limited to these examples.

[0101] The materials used in the examples and comparative examples are shown below.

[0102] (Component (A)) To synthesize component (A), bisimide phenol compounds having structures (a1) to (a5), cresol compounds having structures (b1) to (b2), 1,4-bis(methoxymethyl)benzene, 4,4-bis(methoxymethyl)biphenyl, and 37% by mass of formaldehyde were prepared.

[0103] Alkali-soluble resins were synthesized having the structural units (molar ratios) and Mw shown in Table 1. (c1) is a structure introduced by 1,4-bis(methoxymethyl)benzene, (c2) is a structure introduced by 4,4-bis(methoxymethyl)biphenyl, and (c3) is a structure introduced by formaldehyde.

[0104] A1: N,N'-bis(3-hydroxyphenyl)-pyromellitimide, o-cresol, 1,4-bis(methoxymethyl)benzene, 37% by mass of formaldehyde, γ-butyrolactone, and p-toluenesulfonic acid were added to a 1 L three-neck flask equipped with a Dean-Stark apparatus. The mixture was stirred and reacted at 180°C for 6 hours while removing the by-product methanol by dehydration, and then cooled to 40°C. After cooling, the reaction solution was added dropwise to 1 L of ion-exchanged water, and the precipitated resin was filtered off. The filtered resin was vacuum-dried at 80°C for 12 hours to obtain the alkali-soluble resin (A1). A2 to A8: Alkali-soluble resins (A2) to (A8) were obtained in the same manner as in (A1), except that the types and amounts of compounds were changed so as to form the structural units shown in Table 1.

[0105] The Mw of component (A) was measured by gel permeation chromatography (GPC) and calculated using a standard polystyrene calibration curve. The calibration curve was approximated by a cubic equation of a universal calibration curve according to JIS K 7252-2 (2016) using a set of five standard polystyrene samples (PStQuick MP-H, PStQuick B [product name, manufactured by Tosoh Corporation]). The GPC conditions are shown below.

[0106] (GPC conditions) Detector: L-2490 RI (Hitachi High-Tech Corporation) Column: Gelpack GL-R440+R450+R400M (Hitachi High-Tech Corporation) Eluent: tetrahydrofuran (THF) Measurement temperature: 40℃ Flow rate: 2.05mL / min Concentration: 5mg / mL

[0107] [Table 1]

[0108] (Component (A')) A'1: Cresol novolac resin (cresol / formaldehyde novolac resin, m-cresol / p-cresol (molar ratio) = 60 / 40, Mw = 12000, manufactured by Asahi Organic Chemicals Co., Ltd., product name "EP4020G") A'2: A 500 mL four-neck flask equipped with a thermometer, stirrer, and calcium chloride tube was charged with 0.02 mol of Etherdiamine 4000 (BASF), 0.08 mol of 1,12-diaminododecane, and 150 g of N-methyl-2-pyrrolidone, and the resulting mixture was stirred at 60°C to obtain a homogeneous diamine solution. 0.1 mol of 2,2-bis[4-(3,4-dicarboxyphenoxy)phenyl]propane dianhydride was added to the diamine solution in small portions, and the reaction was carried out at 60°C for 1 hour. The reaction mixture was then heated to 170°C while blowing nitrogen gas through it, and the water was azeotropically removed with a portion of the solvent, yielding a polyimide resin solution, designated A'2.

[0109] ((B) component) B1: 1-naphthoquinone-2-diazide-5-sulfonic acid ester of 1,1-bis(4-hydroxyphenyl)-1-[4-{1-(4-hydroxyphenyl)-1-methylethyl}phenyl]ethane (esterification rate approximately 90%, manufactured by Daito Chemiks Co., Ltd., product name "PA28")

[0110] ((C) component) C1: 4,4'-[1-[4-[1-[4-hydroxy-3,5-bis(methoxymethyl)phenyl]-1-methylethyl]phenyl]ethylidene]bis[2,6-bis(methoxymethyl)phenol] (manufactured by Honshu Chemical Industry Co., Ltd., trade name "HMOM-TPPA") C2: Trifunctional epoxy isocyanurate (manufactured by Nissan Chemical Co., Ltd., product name "TEPIC-VL")

[0111] ((D) component) D1: Into a 100 mL three-neck flask equipped with a stirrer, a nitrogen inlet tube, and a thermometer, 55 g of ethyl lactate was weighed out, and separately weighed polymerizable monomers (34.7 g of n-butyl acrylate (BA), 2.2 g of lauryl acrylate (LA), 3.9 g of acrylic acid (AA), 2.6 g of hydroxybutyl acrylate (HBA), and 1.7 g of 1,2,2,6,6-pentamethylpiperidin-4-yl methacrylate (trade name: FA-711MM, manufactured by Showa Denko Materials Co., Ltd.) and azobisisobutyronitrile were added. 0.29 g of (AIBN) was added. While stirring at approximately 160 rpm at room temperature, nitrogen gas was passed through at a flow rate of 400 mL / min for 30 minutes to remove dissolved oxygen. The nitrogen gas flow was then stopped, the flask was sealed, and the temperature was raised to 65°C in approximately 25 minutes in a thermostatic water bath. The same temperature was maintained for 10 hours to carry out a polymerization reaction, yielding acrylic resin D1. The polymerization rate at this time was 99%. The weight-average molecular weight of D1 was approximately 22,000. The molar ratio of the polymerizable monomers in D1 is as follows: BA / LA / AA / HBA / FA711MM=69 / 2 / 20 / 5 / 4(mol%)

[0112] ((E) component) E1: 5-aminotetrazole (manufactured by Toyobo Co., Ltd., trade name "HAT")

[0113] Examples 1 to 9 The components (A), (B), and (C) in the amounts shown in Table 2 and ethyl lactate as a solvent were mixed, and the mixture was filtered under pressure using a polytetrafluoroethylene filter with 0.2 μm pores to prepare a photosensitive resin composition.

[0114] (Comparative Examples 1 to 3) Photosensitive resin compositions were prepared in the same manner as in Examples, except that the components (A'), (B) and (C) were used in the amounts shown in Table 3.

[0115] [Evaluation of Photosensitive Resin Composition] (exterior) The appearance of the photosensitive resin composition was visually observed, and if it was transparent it was rated as "A", if it was slightly cloudy it was rated as "B", and if it was severely cloudy it was rated as "C". If the cloudiness of the photosensitive resin composition is rated as "A" or "B", it is possible to recognize the alignment marks marked on the substrate when manufacturing a semiconductor device having a patterned cured film formed using the photosensitive resin composition.

[0116] (pattern openness) The photosensitive resin composition was spin-coated onto a silicon substrate and heated at 120°C for 3 minutes to form a coating film with a thickness of 7 to 9 μm. Next, using an i-line stepper (Canon, product name "FPA-3000iW"), the film was subjected to reduction projection exposure with i-line (365 nm) through a mask having a square hole pattern ranging from 1 μm x 1 μm to 100 μm x 100 μm. The exposure dose was 800 mJ / cm. 2 After exposure, the film was developed using a 2.38% aqueous TMAH solution and rinsed with water to obtain a patterned resin film. The opening property of the 100 μm×100 μm square hole pattern was evaluated according to the following criteria. A: The pattern is open, and there is no peeling of the pattern or residual melting at the opening. B: The pattern is open, but peeling of the pattern or unmelted residue can be seen in the opening. C: The pattern itself cannot be formed.

[0117] (resolution) The patterned resin film was heat-treated in nitrogen at 230°C (heating time: 1 hour) for 2 hours using an inert gas oven (manufactured by Koyo Thermo Systems Co., Ltd., product name "INH-9CD-S"), and the resolution of the patterned cured film was evaluated. The smallest size of the openings in the square hole pattern, ranging from 1 μm x 1 μm to 100 μm x 100 μm, was used as an index of fine processing ability. The smaller the pattern size, the better the resolution and the more fine processing is possible.

[0118] (Cure shrinkage) The cure shrinkage rate was calculated from the film thickness of the patterned resin film before curing and the film thickness of the patterned cured film after curing according to the following formula. Curing shrinkage rate (%) = [1 - (thickness of patterned cured film / thickness of patterned resin film)] x 100

[0119] (breaking elongation, breaking strength) The photosensitive resin composition was spin-coated onto a silicon substrate and heated at 120°C for 4 minutes to form a coating film with a thickness of approximately 8 to 9 μm. This coating film was then exposed to 1000 mJ / cm2 at all wavelengths through a mask using a proximity exposure machine (Canon Inc., product name "PLA-600FA"). 2 After exposure, the resist pattern was developed using a 2.38% aqueous solution of TMAH to obtain a 10 mm wide resist pattern. The resist pattern was then heat-treated (cured) in nitrogen at 230°C (heating time: 1 hour) for 2 hours using an inert gas oven (INH-9CD-S), to obtain a cured film with a thickness of approximately 7 μm.

[0120] The cured film was peeled off from the silicon substrate, and the breaking elongation of the peeled cured film was measured using an autograph AGS-H100N manufactured by Shimadzu Corporation. The sample width was 10 mm, the film thickness was approximately 10 μm, and the chuck distance was 20 mm. The pulling speed was 5 mm / min, and the measurement temperature was approximately room temperature (20°C to 25°C). The breaking elongation and breaking strength were determined by averaging the top three measurements of five test pieces obtained from cured films obtained under the same conditions.

[0121] [Table 2]

[0122] [Table 3]

[0123] The resin compositions of the Examples containing component (A) were able to form cured films with good pattern opening properties and high resolution, little cure shrinkage, and high breaking strength. On the other hand, the resin compositions of Comparative Examples 2 and 3 containing the imide resin (A'2) failed to form pattern openings. Furthermore, the resin composition of Comparative Example 1 containing the phenolic resin (A'1) showed some pattern peeling, and the cured film showed greater cure shrinkage and inferior breaking strength compared to the resin compositions of the Examples.

[0124] (Examples 10 to 11) Photosensitive resin compositions were prepared in the same manner as in Examples 1 to 9, except that the components (A) to (D) shown in Table 4 were used in the amounts shown.

[0125] (Examples 12 to 13) Photosensitive resin compositions were prepared in the same manner as in Examples 1 to 9, except that the components (A), (C), and (E) shown in Table 4 were used in their blending amounts.

[0126] (adhesion) The photosensitive resin composition was spin-coated onto a copper substrate (a silicon substrate on which TiN was sputtered, and then copper was sputtered onto the TiN) and heated at 120°C for 3 minutes to form a coating film with a thickness of 10 to 11 μm. The coating was then heat-treated (cured) in nitrogen for 2 hours at 230°C (heat-up time: 1 hour) using an inert gas oven (INH-9CD-S), yielding a cured film with a thickness of approximately 10 μm. The cured film was subjected to the cross-cut test described below to evaluate its adhesion to the copper substrate.

[0127] In the center of the surface of the cured film on the copper substrate, 11 parallel lines are drawn at 1mm intervals in the vertical and horizontal directions using a cutter guide. 2A checkerboard pattern of cuts was made in the photosensitive film to create 100 squares, and the condition of the cuts was evaluated. The cuts were made by holding the edge of a utility knife at a constant angle of 35-45 degrees to the photosensitive film and drawing each cut at a constant speed over 0.5 seconds so that it penetrated the cured film and reached the copper substrate. The more squares that adhered neatly to the copper substrate, the better the adhesion. The results were evaluated on a four-level scale of A, B, C, and D according to the following criteria. A: There is no peeling at the intersections of the cuts or at each square, and the area of ​​the missing parts is less than 1% of the total square area. B: There is slight peeling at the intersections of the cuts, and no peeling across any of the squares, with the area of ​​the missing parts being less than 5% of the total square area. C: There is peeling on both sides and at the intersection of the incision, and the area of ​​the missing part is 5-50% of the total square area. D: The width of the peeling due to the cut is large, and the area of ​​the missing part is greater than 50% of the total square area.

[0128] [Table 4]

[0129] The photosensitive resin compositions of Examples 10 and 11 further contained component (D), which further improved the strength and breaking elongation of the cured film, and the photosensitive resin compositions of Examples 12 and 13 further contained component (E), which improved the adhesion to Cu substrates.

Claims

1. (A) an alkali-soluble resin having an imide bond and a phenolic hydroxyl group; and (B) a compound that generates an acid when exposed to light, The photosensitive resin composition, wherein the alkali-soluble resin is a resin further having a structural unit derived from bis(methoxymethyl)biphenyl or dimethoxymethylbenzene.

2. 2. The photosensitive resin composition according to claim 1, wherein the alkali-soluble resin is a resin having a bisphenolimide skeleton.

3. 3. The photosensitive resin composition according to claim 1, wherein the alkali-soluble resin has a structure derived from at least one selected from the group consisting of a compound represented by the following formula (I), a compound represented by the following formula (II), and a compound represented by the following formula (III): 【Chemistry 1】 (In the formula, R １ , R ２ , R ３ , R ４ , R ５ , and R ６ each independently represents a hydrogen atom or a methyl group, R ａ and R ｂ each independently represents an ether bond, a thioether bond, a carbonyl group, an alkylene group having 1 to 3 carbon atoms, or a single bond.

4. The photosensitive resin composition according to any one of claims 1 to 3, wherein the alkali-soluble resin has a structural unit derived from a compound represented by the following formula (1), (2), (3), (4), (5), or (6): 【Chemistry 2】 (In the formula, R ａ and R ｂ each independently represents an ether bond, a thioether bond, a carbonyl group, an alkylene group having 1 to 3 carbon atoms, or a single bond.

5. 5. The photosensitive resin composition according to claim 1, wherein the compound that generates an acid when exposed to light is an o-quinonediazide compound.

6. The photosensitive resin composition according to any one of claims 1 to 5, further comprising (C) a compound that undergoes a crosslinking reaction by heat.

7. 7. The photosensitive resin composition according to claim 6, wherein the compound that undergoes a crosslinking reaction when heated is a compound having an alkoxy group or an epoxy group.

8. The photosensitive resin composition according to any one of claims 1 to 7, further comprising (D) an elastomer.

9. The photosensitive resin composition according to any one of claims 1 to 8, further comprising (E) an adhesion aid.

10. The photosensitive resin composition according to claim 9 , wherein the adhesion promoter is a nitrogen-containing aromatic compound.

11. A step of applying the photosensitive resin composition according to any one of claims 1 to 10 to a part or the entire surface of a substrate and drying the composition to form a resin film; a step of exposing a part or the entire surface of the resin film to light; a step of developing the exposed resin film with an alkaline aqueous solution to form a patterned resin film; and heating the patterned resin film.

12. A patterned cured film having a pattern, the pattern comprising a cured product of the photosensitive resin composition according to any one of claims 1 to 10.

13. A semiconductor device comprising the patterned cured film according to claim 12 as an interlayer insulating layer or a surface protective layer.

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