Positive type photosensitive resin composition, insulating resin film, method for forming an insulating resin film, and semiconductor device

Abstract

A positive photosensitive resin composition comprising (A) an alkali-soluble resin having phenolic hydroxyl groups and imide groups, (B) a photogenerator which is a compound that generates acid upon light, (C) a thermal crosslinking agent which is a compound that crosslinks the alkali-soluble resin upon heat, and (D) an acrylic elastomer. The acrylic elastomer comprises monomer units having polyoxyalkylene groups.

Description

Technology Field

[0001] The present disclosure relates to a positive type photosensitive resin composition, an insulating resin film having a pattern including an opening, a method for forming an insulating resin film having a pattern including an opening, and a semiconductor device. Background Technology

[0002] Patent Document 1 discloses a positive-type photosensitive resin composition comprising an alkali-soluble resin having an imide bond and a phenolic hydroxyl group, as a material capable of forming a surface protection layer or an interlayer insulating layer of a semiconductor device. Prior art literature

[0003] Patent Document 1: International Publication No. 2021 / 261448 The problem to be solved

[0004] The present disclosure relates to a positive type photosensitive resin composition capable of forming a photosensitive layer with low turbidity and also forming an insulating resin film exhibiting high mechanical strength and large elongation upon thermal curing. means of solving the problem

[0005] The present disclosure includes the following.

[0006] [1]

[0007] (A) an alkali-soluble resin having phenolic hydroxyl groups and imide groups, and

[0008] (B) a photogenerator, which is a compound that generates acid by light, and

[0009] (C) A thermal crosslinking agent, which is a compound that crosslinks the alkali-soluble resin by heat, and

[0010] (D) Comprising an acrylic elastomer which is a polymer comprising monomer units derived from (meth)acrylic acid esters, and

[0011] A positive-type photosensitive resin composition in which the above-mentioned acrylic elastomer comprises monomer units having polyoxyalkylene groups.

[0012] [2]

[0013] The monomer unit having a polyoxyalkylene group is given by the following formula (51):

[0014] [Chemical Formula 1]

[0015]

[0016] It is a monomer unit represented as, and R 50 This represents a hydrogen atom or a methyl group, and R 51 This represents an alkylene group, and R 52 A positive photosensitive resin composition as described in [1], wherein g represents a hydrocarbon group and n represents an integer greater than or equal to 2.

[0017] [3]

[0018] A positive photosensitive resin composition as described in [1] or [2], wherein the ratio of the monomer units having polyoxyalkylene groups is 50 mol% or more based on the total monomer units in the acrylic elastomer.

[0019] [4]

[0020] A positive photosensitive resin composition described in any one of [1] to [3], wherein the above acrylic elastomer further comprises monomer units having hydroxyl groups.

[0021] [5]

[0022] The above alkali-soluble resin is of the following formula (I):

[0023] [Chemical Formula 2]

[0024]

[0025] It comprises a constituent unit obtained by removing one or more hydrogen atoms from a bisphenolimide compound represented as, and R 1 This is a hydrogen atom or a carbon-1 to carbon-3 alkyl group, and Z 1 A positive-type photosensitive resin composition described in any one of [1] to [4], which is a tetravalent organic group.

[0026] [6]

[0027] A positive-type photosensitive resin composition described in any one of [1] to [5], wherein the above-mentioned thermal crosslinking agent comprises an alkoxy compound having a plurality of alkoxy groups.

[0028] [7]

[0029] [1] Exposing a portion of a photosensitive layer comprising a positive type photosensitive resin composition described in any one of [1] to [6], and

[0030] Forming an insulating resin film having a pattern including an opening by removing a portion of the above photosensitive layer, and

[0031] A method for forming an insulating resin film, comprising heating the insulating resin film.

[0032] [8]

[0033] An insulating resin film comprising a cured positive-type photosensitive resin composition described in any one of [1] to [6], and having a pattern including an opening.

[0034] [9]

[0035] semiconductor chips and,

[0036] A wiring portion comprising a conductive wiring layer connected to the semiconductor chip and one or more insulating layers, and

[0037] A semiconductor device in which at least one of the above insulating layers is an insulating resin film as described in [8]. Effects of the invention

[0038] A photosensitive resin composition may be provided that can form a photosensitive layer with low turbidity and, furthermore, form an insulating resin film exhibiting high mechanical strength and high elongation by thermal curing. Low turbidity in the photosensitive layer is advantageous in terms of ensuring alignment during exposure. An insulating resin film exhibiting high mechanical strength and high elongation can contribute to improving the reliability of semiconductor devices. The photosensitive resin composition according to the present disclosure can also exhibit good characteristics in terms of film thickness uniformity and resolution of the photosensitive layer or the insulating resin film. Brief explanation of the drawing

[0039] Figure 1 is a flowchart showing an example of a method for forming an insulating resin film having a pattern. Figure 2 is a partial cross-sectional view showing an example of a semiconductor device. Specific details for implementing the invention

[0040] The present invention is not limited to the following examples. In this disclosure, the term "process" includes not only independent processes but also processes that cannot be clearly distinguished from other processes as long as the desired function of the process is achieved. The term "layer" includes, in addition to the structure of a shape formed on the entire surface when observed as a plan view, a structure of a shape formed on a part thereof. A numerical range indicated by "~" indicates a range that includes the values ​​listed before and after "~" as the minimum and maximum values, respectively. In numerical ranges described stepwise in this specification, the upper or lower limit of a numerical range in any step may be substituted with the upper or lower limit of a numerical range in another step. In numerical ranges described in this specification, the upper or lower limit of such numerical range may be substituted with the values ​​shown in the examples.

[0041] Photosensitive resin composition

[0042] An example of a photosensitive resin composition comprises (A) an alkali-soluble resin having phenolic hydroxyl groups and imide groups, (B) a photogenerator which is a compound that generates acid upon light, (C) a thermal crosslinking agent which is a compound that crosslinks the alkali-soluble resin upon heat, and (D) an acrylic elastomer. The photosensitive resin composition according to the present disclosure can function as a positive type photosensitive resin composition based on a change in solubility in an alkaline developer upon exposure to light. Furthermore, a film comprising the photosensitive resin composition according to the present disclosure can be thermally cured primarily by the crosslinking reaction between the thermal crosslinking agent and the alkali-soluble resin to form an insulating resin film, which is a cured film comprising a cured product of the photosensitive resin composition.

[0043] (A) Alkali-soluble resin

[0044] The alkali-soluble resin may be a polymer having constituent units having phenolic hydroxyl groups and imide groups. The alkali-soluble resin may have an imide group and a cyclic imide group comprising a hydrocarbon group that forms a cyclic structure together with the imide group. The cyclic imide group may be a five-membered ring. The alkali-soluble resin may include an aromatic group, a dicyclic group, or both that form a condensation ring with the cyclic imide group.

[0045] The alkali-soluble resin having a cyclic imide group may be, for example, a polymer comprising a constituent unit obtained by removing one or more hydrogen atoms from a bisphenolimide compound represented by the following formula (I). In formula (I), R 1 This is a hydrogen atom or a C1- to C3 alkyl group (e.g., a methyl group), and Z 1 This is a tetravalent organic group. An alkali-soluble resin having a constituent unit derived from a bisphenolimide compound represented by formula (I) may be a novolak resin containing a constituent unit derived from a bisphenolimide compound represented by formula (I).

[0046] [Chemical Formula 3]

[0047]

[0048] Z 1 One cyclic hydrocarbon group that may have this substituent (e.g., an alkyl group having 1 to 3 carbon atoms), or two or more cyclic hydrocarbons that may have the substituent (e.g., an alkyl group having 1 to 3 carbon atoms) and a divalent organic group or covalent bond that combines them.

[0049] Z 1 Examples of cyclic hydrocarbon groups include groups obtained by removing one or more hydrogen atoms from the following cyclic hydrocarbon compounds.

[0050] [Chemical Formula 4]

[0051]

[0052] Z 1 Among them, the divalent organic group bonding two cyclic hydrocarbon groups is a divalent group selected from, for example, an oxy group (-O-), a thio group (-S-), a carbonyl group, an alkylene group having 1 to 3 carbon atoms, a phenylene group, an alkylphenylene group, and combinations thereof. Examples of alkylene groups having 1 to 3 carbon atoms include a methylene group, an ethylene group, an ethylidene group, a propane-1,3-diyl group, a propane-1,1-diyl group, and a propane-2,2-diyl group. Z 1 Specific examples of divalent organic groups that combine two cyclic hydrocarbon groups include, in addition to alkylene groups having 1 to 3 carbon atoms, the following.

[0053] [Chemical Formula 5]

[0054]

[0055] Among these formulas, R 10 represents an alkyl group having 1 to 3 carbon atoms (e.g., a methyl group), and multiple Rs in the same molecule 10 may be the same or different. q represents an integer from 0 to 4, and multiple qs within a single expression may be the same or different. R 11represents an alkylene group (e.g., propane-2,2-diyl group, methylene group), an oxy group, a thio group, or a direct bond. R 12 represents an alkylene group (e.g., ethane-1,2-diyl group).

[0056] The bisphenolimide compound may be a compound represented by the following formulas (IA), (IB), or (IC). R in formulas (IA), (IB), and (IC). 1 is R in Equation (I) 1 It is defined identically to. R in equation (IB) 2 represents a direct bond (covalent bond) or a divalent organic group. R 2 An example of a divalent organic group as is Z 1 Among them, it includes those identical to the examples given as divalent organic groups combining two cyclic hydrocarbon groups. R in formula (IC) 3 It represents silver, a hydrogen atom, or an alkyl group having 1 to 3 carbon atoms (e.g., a methyl group).

[0057] [Chemical Formula 6]

[0058]

[0059] [Chemical Formula 7]

[0060]

[0061] [Chemical Formula 8]

[0062]

[0063] Equation (IB) may be, for example, the following equation (IB'). R in equation (IB'). 1 and R 2 is R in equation (IB) 1 and R 2 It is defined identically to.

[0064] [Chemical Formula 9]

[0065]

[0066] In a bisphenolimide compound represented by formulas (IA), (IB), or (IB'), at least one of the two phenolic hydroxyl groups may be bonded to a meta or ortho position with respect to the imide group for the purpose of improving solubility in solvents. Examples of a bisphenolimide compound represented by formula (IA) in which a phenolic hydroxyl group is bonded to a meta or ortho position with respect to the imide group include compounds represented by the following formulas (IA-1), (IA-2), (IA-3), or (IA-4). Examples of a bisphenolimide compound represented by formula (IB) in which a phenolic hydroxyl group is bonded to a meta or ortho position with respect to the imide group include compounds represented by the following formulas (IB-1), (IB-2), (IB-3), or (IB-4). These compounds tend to have an excellent balance of solubility and mechanical strength. R in formulas (IB-1), (IB-2), (IB-3), and (IB-4). 2 is R in equation (IB) 2 It is defined identically to.

[0067] [Chemical Formula 10]

[0068]

[0069] [Chemical Formula 11]

[0070]

[0071] A novolak resin comprising a constituent unit derived from a bisphenolimide compound represented by formula (I) may have a polymer chain in which a constituent unit derived from a phenol compound selected from phenol, o-cresol, m-cresol, and p-cresol, or a constituent unit derived from a bisphenolimide compound, and a constituent unit derived from a reactive compound selected from an aldehyde compound, a compound having multiple methoxymethyl groups, and a compound having multiple hydroxymethyl groups are alternately bonded. The constituent unit derived from the bisphenolimide compound may be a residue in which one or more hydrogen atoms have been removed from an aromatic group (particularly a benzene ring to which a phenolic hydroxyl group is bonded) of the bisphenolimide compound. The constituent unit derived from the bisphenolimide compound may be bonded to another constituent unit at an ortho or para position relative to the phenolic hydroxyl group.

[0072] The aldehyde compound constituting the novolak resin may be formaldehyde. The compound having multiple methoxymethyl groups may be a compound having an aromatic ring (e.g., a benzene ring) to which the methoxymethyl group is attached. The compound having multiple hydroxymethyl groups may be a compound having an aromatic ring (e.g., a benzene ring) to which the hydroxymethyl group is attached. Examples of compounds having multiple methoxymethyl groups include compounds represented by the following formulas (21) or (22). Among these formulas, R 10 represents an alkyl group having 1 to 3 carbon atoms (e.g., a methyl group). Multiple Rs in the same molecule 10 may be the same or different. p represents an integer from 0 to 4, and q and r each independently represent integers from 0 to 4. A compound having multiple methoxymethyl groups may be bis(methoxymethyl)biphenyl, dimethoxymethylbenzene, or a combination thereof. Examples of compounds having multiple hydroxymethyl groups include 2,6-bis(hydroxymethyl)-p-cresol.

[0073] [Chemical Formula 12]

[0074]

[0075] The residue derived from formaldehyde is typically a methylene group. The residue derived from a compound having two or more methoxymethyl groups may be a divalent group represented, for example, by the following formulas (21A) or (22B). R in formulas (21A) and (22B). 10 , p, q and r are R in equations (21) and (22). 10 It is defined identically to , p, q and r.

[0076] [Chemical Formula 13]

[0077]

[0078] In the reaction for producing novolak resin, the proportion of the bisphenolimide compound in the phenol compound reacting with the aldehyde compound, etc., may be 10 mol% or more and 100 mol% or less, 20 mol% or more and 100 mol% or less, 30 mol% or more and 100 mol% or less, or 40 mol% or more and 100 mol% or less, based on the total amount of the phenol compound. If the proportion of the bisphenolimide compound is high, it is easy to obtain particularly excellent effects in terms of good shape and high resolution of the insulating resin film. In the same view, the proportion of the bisphenolimide compound may be 50 mol% or more, 60 mol% or more, 70 mol% or more, 80 mol% or more, or 90 mol% or more, based on the total amount of the phenol compound, and may substantially be 100 mol%.

[0079] Novolak resin, which is an alkali-soluble resin, can be synthesized, for example, by a method similar to the synthesis method of general phenol novolak resin or cresol novolak resin.

[0080] The weight average molecular weight (Mw) of the alkali-soluble resin may be 1,000 to 500,000, 2,000 to 400,000, 3,000 to 350,000, or 5,000 to 300,000, in terms of the balance of solubility in an alkaline aqueous solution, photosensitive properties, and mechanical strength of the insulating resin film. In the present disclosure, the weight average molecular weight is a converted value based on a standard polystyrene calibration curve measured by gel permeation chromatography (GPC).

[0081] (C) Photocatalyst

[0082] (C) The photogenerator of the component comprises one or more compounds that generate acid upon light (e.g., ultraviolet light) and functions as a photosensitive agent in a photosensitive resin composition. Due to the action of the acid generated from the photogenerator upon the absorption of light, the solubility in an alkaline aqueous solution is selectively increased in the portion of the photosensitive layer that is irradiated with light.

[0083] The compound constituting the photogenerator may be selected from compounds generally used as photogenerators. The compound that generates acid upon light may be, for example, an o-quinone diazide compound, an aryldiazonium salt, a diaryliodonium salt, and a triarylsulfonium salt, or a combination of two or more selected from these.

[0084] In terms of improving exposure sensitivity, the photogenerator may include an o-quinone diazide compound. The o-quinone diazide compound comprises an aromatic group, an oxo group (=O), and a diazide group (=N). + =N - It is a compound having an oxo group and a diazide group, respectively, bonded to an adjacent carbon atom in the aromatic group. The aromatic group is, for example, a contribution made by removing a hydrogen atom from naphthalene or benzene.

[0085] o-quinone diazide compounds may have a group comprising an oxo group and a diazide group, for example, represented by the following formulas (3a), (3b) or (3c).

[0086] [Chemical Formula 14]

[0087]

[0088] [Chemical Formula 15]

[0089]

[0090] [Chemical Formula 16]

[0091]

[0092] A compound having a group represented by formulas (3a), (3b), or (3c) may be, for example, the product of a condensation reaction of o-quinone diazide sulfonyl chloride and a hydroxy compound and / or amino compound in the presence of a dehydrochlorination agent. In this case, the o-quinone diazide compound may be a compound having a residue derived from a hydroxy compound or an amino compound and a group represented by formulas (3a), (3b), or (3c). For example, a compound having a group represented by formula (3a) can be obtained from naphthoquinone-1,2-diazide-5-sulfonyl chloride. A compound having a group represented by formula (3b) can be obtained from naphthoquinone-1,2-diazide-6-sulfonyl chloride. A compound having a group represented by formula (3c) can be obtained from benzoquinone-1,2-diazide-4-sulfonyl chloride.

[0093] A hydroxyl compound that can be used to synthesize an o-quinone diazide compound is a compound having one or more hydroxyl groups. A residue of the hydroxyl compound may be a group obtained by removing one or more hydrogen atoms from the hydroxyl group of the hydroxyl compound. Examples of hydroxy compounds are 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, 2,2',4,4'-tetrahydroxybenzophenone, 2,3,4,2',3'-pentahydroxybenzophenone, 2,3,4,3',4',5'-hexahydroxybenzophenone, bis(2,3,4-trihydroxyphenyl)methane, It includes 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.

[0094] Specific examples of compounds having a residue of a hydroxyl compound and a group represented by formulas (3a), (3b), or (3c) include compounds represented by the following formulas (31), (32), (33), (34), (35), or (36). These compounds are prone to absorbing light in a wavelength range suitable for the exposure of a photosensitive layer.

[0095] [Chemical Formula 17]

[0096]

[0097] [Chemical Formula 18]

[0098]

[0099] [Chemical Formula 19]

[0100]

[0101] [Chemical Formula 20]

[0102]

[0103] [Chemical Formula 21]

[0104]

[0105] [Chemical Formula 22]

[0106]

[0107] In formulas (31) to (36), Q represents a group represented by formula (3a), (3b), or (3c), or a hydrogen atom, and multiple Qs in the same molecule may be the same or different, and at least one of multiple Qs in the same molecule is a group represented by formula (3a), (3b), or (3c). In formulas (31) to (36), R 30 represents an alkyl group having 1 to 3 carbon atoms (e.g., a methyl group), and multiple Rs in the same molecule 30 may be the same or different. In Equation (31), R 31 represents an alkane triyl group having 1 to 3 carbon atoms (e.g., a methane triyl group, or an ethane-1,1,1-triyl group), and a plurality of p each independently represents an integer from 0 to 4. In Equation (32), a plurality of q each independently represents an integer from 0 to 4. In Equation (33), a plurality of r each independently represents an integer from 0 to 4, and a plurality of s each independently represents an integer from 0 to 3. In Equation (34), a plurality of t each independently represents an integer from 0 to 4. In Equation (35), a plurality of u each independently represents an integer from 0 to 4, and a plurality of v each independently represents an integer from 0 to 3. In Equation (36), w represents an integer from 0 to 4, and x represents an integer from 0 to 2.

[0108] An amino compound that can be used to synthesize an o-quinone diazide compound is a compound having one or more amino groups. A residue of the amino compound may be a group obtained by removing one or more hydrogen atoms from the amino group of the amino compound. Examples of amino compounds are p-phenylenediamine, m-phenylenediamine, 4,4'-diaminodiphenyl ether, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylsulfone, 4,4'-diaminodiphenylsulfide, 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 It contains bis(4-amino-3-hydroxyphenyl)hexafluoropropane.

[0109] The content of the photogenerator may be 1 to 50 mass%, 3 to 35 mass%, or 5 to 20 mass% with respect to the content of the alkali-soluble resin of component (A) for good sensitivity.

[0110] (C) Thermal crosslinking agent

[0111] (C) The thermal crosslinking agent of component C comprises one or more compounds that crosslink an alkali-soluble resin by heat. The compound constituting the thermal crosslinking agent may have multiple functional groups capable of reacting with the alkali-soluble resin and bonding to the molecular chains of the alkali-soluble resin. Examples of such functional groups include alkoxy groups, epoxy groups, and oxazoline groups. The thermal crosslinking agent may also include an alkoxy compound having multiple alkoxy groups.

[0112] It is believed that an alkoxy compound that can be used as a thermal crosslinking agent functions as a thermal crosslinking agent that crosslinks the molecular chains of an alkali-soluble resin mainly through the reaction of an aromatic group (phenylene group) to which a phenolic hydroxyl group is attached with an alkoxy group. The number of alkoxy groups in the alkoxy compound may be 2 or more, 3 or more, or 4 or more, and may be 20 or less, 15 or less, or 10 or less.

[0113] At least some of the two or more alkoxy groups of the alkoxy compound may be methoxy groups. In other words, the alkoxy compound may have multiple methoxy groups. The alkoxy compound may have four or more methoxy groups.

[0114] The alkoxy compound may have a cyclic group from which one or more hydrogen atoms have been removed from benzene, 1,3,5-triazine, glycoluryl, 2-imidazolidinone, or urea, and an alkoxyalkyl group (e.g., methoxymethyl group, 1,3-dimethoxypropane-2-yl group) may be bonded to the cyclic group. An alkoxy compound having a cyclic group from which a hydrogen atom has been removed from benzene (benzene ring) may have a phenolic hydroxyl group bonded to the cyclic group. In the present disclosure, a compound having an alkoxy group and a phenolic hydroxyl group may be considered as a thermal crosslinking agent of component (C) rather than an alkali-soluble resin. An alkoxy compound having an alkoxy group and a phenolic hydroxyl group may contribute to improving the sensitivity of a photosensitive resin composition.

[0115] The weight average molecular weight of the alkoxy compound may be 3000 or less, 2000 or less, or 1500 or less, or 100 or more, in terms of the balance of solubility in alkaline developer, photosensitive properties, and mechanical strength.

[0116] Specific examples of alkoxy compounds having a phenolic hydroxyl group include compounds represented by the following formulas (41), (42), (43), (44), (45) or (46). Specific examples of alkoxy compounds having a cyclic group from which one or more hydrogen atoms have been removed from 1,3,5-triazine, glycoluryl, 2-imidazolidinone, or urea include compounds represented by the following formulas (47), (48), (49) or (50).

[0117] [Chemical Formula 23]

[0118]

[0119] [Chemical Formula 24]

[0120]

[0121] [Chemical Formula 25]

[0122]

[0123] [Chemical Formula 26]

[0124]

[0125] [Chemical Formula 27]

[0126]

[0127] [Chemical Formula 28]

[0128]

[0129] [Chemical Formula 29]

[0130]

[0131] [Chemical Formula 30]

[0132]

[0133] [Chemical Formula 31]

[0134]

[0135] [Chemical Formula 32]

[0136]

[0137] Among equations (41) to (50), R 40represents an alkoxyalkyl group, and multiple Rs in the same molecule 40 It may be the same or different. R 40 It may be a methoxyalkyl group or a dimethoxyalkyl group, examples of which include a methoxymethyl group (-CH2OCH3) and a 1,3-dimethoxypropane-2-yl group represented by the following formula.

[0138] [Chemical Formula 33]

[0139]

[0140] The content of the thermal crosslinking agent (or alkoxy compound) may be 1 to 70 mass%, 2 to 50 mass%, or 3 to 40 mass% with respect to the content of the alkali-soluble resin of component (A), in terms of heat resistance and warping inhibition of the insulating resin film (cured film).

[0141] (D) Acrylic elastomer

[0142] An acrylic elastomer is a polymer comprising one or more (meth)acrylic acid esters as monomer units. The (meth)acrylic acid ester may be an alkyl (meth)acrylic acid ester having an alkyl group that may have a substituent. "(meth)acrylic" means acrylic and methacrylic.

[0143] The acrylic elastomer comprises one or more monomer units having a polyoxyalkylene group. The polyoxyalkylene group is of the formula: -(OR 51 ) n It is a unit that can be represented as -, and R 51 represents an alkylene group, and n represents an integer greater than or equal to 2. R 51 ... may be an alkylene group having 2 to 5 carbon atoms. The number of repeating oxyalkylene groups, n, may be 10 or less, 5 or less, or 3 or less. Examples of polyoxyalkylene groups include polyoxyethylene groups (-(OCH2CH2) n -), and polypropylene groups (-(OCH(CH3)CH2) n Includes -). Monomer units having polyoxyalkylene groups contribute to not having hydroxyl groups, carboxyl groups, and amino groups.

[0144] Monomer units having polyoxyalkylene groups may be monomer units derived from (meth)acrylic acid esters having polyoxyalkylene groups, and examples include those represented by the following formula (51).

[0145] [Chemical Formula 34]

[0146]

[0147] In equation (51), R 50 represents a hydrogen atom or a methyl group, and R 51 represents an alkylene group, and R 52 represents a hydrocarbon group, and n represents an integer greater than or equal to 2. R 51 An example of is as described above. R 52 It may be an unsubstituted alkyl group having 1 to 6 carbon atoms (e.g., methyl group, ethyl group) or an aryl group (e.g., phenyl group).

[0148] The acrylic elastomer may further include monomer units other than monomer units having polyoxyalkylene groups. The proportion of monomer units having polyoxyalkylene groups in the acrylic elastomer may be 50 mol% or more, 55 mol% or more, 60 mol% or more, 65 mol% or more, or 70 mol% or more, based on the total monomer units included in the acrylic elastomer, or 95 mol% or less, 90 mol% or less, 85 mol% or less, or 80 mol% or less. If the proportion of monomer units having polyoxyalkylene groups is within these ranges, particularly significant effects are easily obtained in terms of reducing the turbidity of the photosensitive layer and high mechanical strength and large elongation of the insulating resin film.

[0149] The acrylic elastomer may further include monomer units having hydroxyl groups. Monomer units having hydroxyl groups may also be non-polyoxyalkylene groups, carboxyl groups, and amino groups. Monomer units having hydroxyl groups may be monomer units derived from (meth)acrylic acid esters having hydroxyalkyl groups or (meth)acrylamides having hydroxyalkyl groups, examples of which include those represented by the following formula (52).

[0150] [Chemical Formula 35]

[0151]

[0152] In equation (52), R 50 represents a hydrogen atom or a methyl group, and Z 2 is -O- or -NH-, and R 53 represents an alkylene group. R 53 The group may be an alkylene group having 1 to 20 carbon atoms, 1 to 10 carbon atoms, or 1 to 4 carbon atoms, examples of which include ethane-1,2-diyl groups and butane-1,4-diyl groups. The proportion of monomer units having hydroxyl groups in the acrylic elastomer may be 1 mol% or more, 2 mol% or more, or 3 mol% or more based on the total monomer units included in the acrylic elastomer, and may be 20 mol% or less, 15 mol% or less, or 10 mol% or less.

[0153] The acrylic elastomer may further comprise monomer units having a carboxyl group. The monomer units having a carboxyl group may also be non-polyoxyalkylene groups, hydroxyl groups, and amino groups. The monomer units having a carboxyl group may be monomer units derived from (meth)acrylic acid esters having a carboxyl group, examples of which include those represented by the following formulas (53A) or (53B).

[0154] [Chemical Formula 36]

[0155]

[0156] Among equations (53A) and (53B), R50 represents a hydrogen atom or a methyl group. In formula (53B), R 54 represents an alkylene group. R 54 The alkylene group may have 1 to 20 carbon atoms, 1 to 10 carbon atoms, or 1 to 4 carbon atoms, and examples include an ethane-1,2-diyl group. The proportion of monomer units having a carboxyl group in the acrylic elastomer may be 3 mol% or more, 5 mol% or more, or 10 mol% or more based on the total monomer units included in the acrylic elastomer, or 30 mol% or less, 25 mol% or less, or 20 mol% or less.

[0157] The acrylic elastomer may further include monomer units having amino groups. Monomer units having amino groups may also be non-polyoxyalkylene groups, hydroxyl groups, and carboxyl groups. Monomer units having amino groups may be monomer units derived from (meth)acrylic acid esters having secondary or tertiary amino groups, examples of which include those represented by the following formula (54).

[0158] [Chemical Formula 37]

[0159]

[0160] In equation (54), R 50 represents a hydrogen atom or a methyl group, and R 55 represents a hydrogen atom or an alkyl group, and R 56 , R 57 , R 58 and R 59 Each represents an alkyl group independently. R 55 may be an alkyl group having 1 to 20, 1 to 10, or 1 to 5 carbon atoms (e.g., a methyl group). 56 , R 57 , R 58 and R 59α may be an alkyl group having 1 to 20, 1 to 10, or 1 to 5 carbon atoms (e.g., a methyl group). The ratio of monomer units having an amino group in the acrylic elastomer may be 1 mol% or more, 2 mol% or more, or 3 mol% or more based on the total monomer units included in the acrylic elastomer, and may be 20 mol% or less, 15 mol% or less, or 10 mol% or less.

[0161] The acrylic elastomer may further include monomer units having unsubstituted alkyl groups. The monomer units having unsubstituted alkyl groups may be monomer units derived from (meth)acrylic acid esters having unsubstituted alkyl groups, examples of which include those represented by the following formula (55).

[0162] [Chemical Formula 38]

[0163]

[0164] In equation (55), R 50 represents a hydrogen atom or a methyl group, and R 60 represents an unsubstituted alkyl group having 4 to 20 carbon atoms. R 60 Examples include butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group (or lauryl group), tridecyl group, tetradecyl group, pentadecyl group, hexadecyl group, heptadecyl group, octadecyl group, nonadecyl group, and eicosyl group.

[0165] The acrylic elastomer may be a copolymer comprising a monomer unit having a polyoxyalkylene group and not having a hydroxyl group, a carboxyl group, or an amino group; a monomer unit having a hydroxyl group and not having a polyoxyalkylene group, a carboxyl group, or an amino group; a monomer unit having a carboxyl group and not having a polyoxyalkylene group, a hydroxyl group, or an amino group; and a monomer unit having an amino group and not having a polyoxyalkylene group, a hydroxyl group, or a carboxyl group. The acrylic elastomer may be a copolymer composed only of a monomer unit having a polyoxyalkylene group, a monomer unit having a hydroxyl group, a monomer unit having a carboxyl group, and a monomer unit having an amino group, or a copolymer composed only of these monomer units and the remainder of monomer units having unsubstituted alkyl groups.

[0166] The content of the acrylic elastomer may be 0.5 mass% or more and 50 mass% or less relative to the content of the alkali-soluble resin. The content of the acrylic elastomer may be 1 mass% or more or 2 mass% or more relative to the content of the alkali-soluble resin, or 40 mass% or less, 30 mass% or less, 20 mass% or less, 15 mass% or less, or 10 mass% or less.

[0167] The photosensitive resin composition may further include other elastomers in addition to the acrylic elastomers exemplified above. Other elastomers include acrylic elastomers, styrene elastomers, olefin elastomers, urethane elastomers, polyester elastomers, polyamide elastomers, and silicone elastomers, which are polymers that do not contain monomer units having polyoxyalkylene groups. The content of other elastomers may be 0 mass% or more and 30 mass% or less, 20 mass% or less, 15 mass% or less, 10 mass% or less, or 5 mass% or less, with respect to the content of alkali-soluble resin.

[0168] In a photosensitive resin composition, the total content of (A) alkali-soluble resin, (B) photogenerator, (C) thermal crosslinking agent, and (D) acrylic elastomer may be 50 mass% or more, 60 mass% or more, 70 mass% or more, 80 mass% or more, 90 mass% or more, or 95 mass% or more, or 100 mass% or less, based on the amount of the photosensitive resin composition. If the photosensitive resin composition contains a solvent, the amount of the photosensitive resin composition herein is the amount excluding the solvent.

[0169] Other ingredients

[0170] The photosensitive resin composition may further contain, in addition to components (A) to (D), other components such as an adhesion aid, a solvent, a compound that generates acid upon heating, a dissolution promoter, a dissolution inhibitor, a Cu rust inhibitor, a coupling agent, and a surfactant and a leveling agent. The photosensitive resin composition may further include an alkali-soluble resin that does not correspond to component (A), separately from component (A).

[0171] The adhesive aid may include a nitrogen-containing aromatic compound, examples of which include 1H-tetrazole, 5-aminotetrazole, 5-phenyltetrazole, and 5-methyltetrazole. The content of the adhesive aid may be 0 to 20 mass%, 0.01 to 20 mass%, 0.015 to 10 mass%, or 0.02 to 7 mass% with respect to the content of the alkali-soluble resin of component (A).

[0172] Examples of solvents include γ-butyrolactone, ethyl lactate, propylene glycol monomethyl ether acetate, benzyl acetate, n-butyl acetate, ethoxyethylpropionate, 3-methyl methoxypropionate, N-methyl-2-pyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, hexamethylphosphorylamide, tetramethylenesulfone, diethyl ketone, diisobutyl ketone, methylamyl ketone, cyclohexanone, propylene glycol monomethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, and dipropylene glycol monomethyl ether. These solvents may be used individually or in combination of two or more. The solvent may include ethyl lactate, γ-butyrolactone, or a combination thereof. In a photosensitive resin composition containing a solvent, the concentration of a component other than the solvent (solid content) may be 1 to 80 mass% based on the mass of the photosensitive resin composition containing the solvent.

[0173] A compound that generates acid upon heating promotes the thermal crosslinking reaction between an alkali-soluble resin and an oxazoline compound or an alkoxy compound, and as a result, the heat resistance of the cured film can be further improved. A compound that generates acid upon heating can also contribute to the improvement of resolution. Examples of compounds that generate acid upon heating include salts formed by a strong acid such as an onium salt and a base, and imidosulfonates. The content of the compound that generates acid upon heating may be 0 to 30 mass%, 0.1 to 30 mass%, 0.2 to 20 mass%, or 0.5 to 10 mass% with respect to the content of the alkali-soluble resin of component (A).

[0174] The dissolution accelerator is a component that increases the dissolution rate of the developer in the exposure area and can contribute to the improvement of sensitivity and resolution. The dissolution accelerator may include a compound having a carboxyl group, a sulfo group, or a sulfonamide group. The content of the dissolution accelerator may be 0 to 30 mass% or 0.01 to 30 mass% with respect to the content of the alkali-soluble resin of component (A).

[0175] A dissolution inhibitor is a compound that inhibits dissolution in an alkaline aqueous solution of the exposure area and is used to control film thickness, development time, and contrast after development. Examples of dissolution inhibitors include diphenyl iodonium nitrate, bis(p-tert-butylphenyl) iodonium nitrate, diphenyl iodonium bromide, diphenyl iodonium chloride, and diphenyl iodonium iodide. The content of the dissolution inhibitor may be 0 to 20 mass%, 0.01 to 20 mass%, 0.01 to 15 mass%, or 0.05 to 10 mass% with respect to the content of the alkali-soluble resin of component (A).

[0176] The coupling agent may include an organosilane compound (silane coupling agent), an aluminum chelate compound, or a combination thereof. Examples of commercially available organosilane compounds include KBM-403, KBM-803, and KBM-903 (manufactured by Shin-Etsu Chemical Co., Ltd., trade name). The content of the coupling agent may be 0 to 20 mass%, 0.1 to 20 mass%, or 0.5 to 10 mass% with respect to the content of the alkali-soluble resin of component (A).

[0177] Examples of surfactants or leveling agents include polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, and polyoxyethylene octylphenol ether. Examples of commercially available products include MegaPac F-171, F-565, and RS-78 (manufactured by DIC Corporation, trade name). The content of the surfactant or leveling agent may be 0 to 5 mass%, 0.001 to 5 mass%, or 0.01 to 3 mass% with respect to the content of the alkali-soluble resin of component (A).

[0178] Method for forming an insulating resin film having a pattern

[0179] An insulating resin film having a pattern including an opening can be formed by photolithography using a photosensitive resin composition according to the present disclosure. FIG. 1 is a flowchart illustrating an example of a method for forming an insulating resin film having a pattern including an opening. The method shown in FIG. 1 includes a process S1 for forming a photosensitive layer comprising a photosensitive resin composition, a process S2 for exposing a portion of the photosensitive layer to light, a process S3 for forming an insulating resin film having a pattern including an opening by developing a portion of the photosensitive layer, and a process S4 for heating the insulating resin film.

[0180] A photosensitive layer comprising a photosensitive resin composition is formed on any substrate, such as, for example, a glass substrate, a semiconductor substrate, a metal oxide insulator substrate (e.g., TiO2, SiO2), or a silicon nitride substrate. The photosensitive layer is formed by a method comprising, for example, applying a positive-type photosensitive resin composition containing a solvent onto a substrate and removing the solvent from a coating film. The coating film may be heated to remove the solvent. The thickness of the photosensitive layer may be 0.1 to 40 μm.

[0181] A portion of the photosensitive layer is exposed by irradiation with active light through a mask. The active light may be ultraviolet light, visible light, or radiation, and may be g-rays, h-rays, i-rays, or a combination thereof.

[0182] A resin film (insulating resin film) having a pattern including an opening is formed by removing a portion of the photosensitive layer. A developer solution may be used for the development. Examples of development in which a developer solution is used include shower development, spray development, immersion development, and puddle development. The resin film (insulating resin film) after development may be washed with water or the like.

[0183] The developer may be an alkaline aqueous solution. The alkaline aqueous solution may contain one or more bases selected from sodium carbonate, sodium hydroxide, potassium hydroxide, sodium silicate, ammonia, ethylamine, diethylamine, triethylamine, triethanolamine, and tetramethylammonium hydroxide (TMAH). The concentration of the base in the alkaline aqueous solution may be 0.1 to 10 mass% based on the mass of the alkaline aqueous solution. The developer may contain an alcohol or a surfactant.

[0184] A portion corresponding to a through hole with a width of 5 μm is exposed to light in a photosensitive layer with a film thickness of 5 μm comprising a photosensitive resin composition, and the photosensitive layer after exposure is at 100 mJ / m² 2 When developed under conditions where a through hole is formed by an aqueous solution of tetramethylammonium hydroxide with a concentration of 2.38 mass% with an exposure amount, the remaining film thickness of the photosensitive layer may be 95% or more of the film thickness of the photosensitive layer before exposure.

[0185] By heating the resin film (insulating resin film), which is a photosensitive layer remaining after development, an insulating resin film is formed, which is a resin film containing a thermosetting product of a photosensitive resin composition, mainly through the reaction between an alkali-soluble resin and a thermal crosslinking agent. The heating temperature may be 300°C or lower, 270°C or lower, or 250°C or lower, or 160°C or higher. The heating time may be, for example, 0.5 hours or more and 5 hours or less.

[0186] The resin film (insulating resin film) can be heated using a heating device such as, for example, a quartz tube, a hot plate, a rapid thermal annealing furnace, a longitudinal diffusion furnace, an infrared curing furnace, an electron beam curing furnace, a microwave curing furnace, a microwave curing device, and a frequency-tunable microwave curing device. The heating atmosphere may be, for example, an atmospheric atmosphere or an inert gas atmosphere containing nitrogen, etc.

[0187] semiconductor device

[0188] The insulating resin film may be, for example, an insulating layer constituting a wiring portion of a semiconductor device. The semiconductor device may have a wiring portion (rewiring portion) comprising a semiconductor chip, a conductor wiring layer connected to the semiconductor chip, and one or more insulating layers, and at least a portion of the one or more wiring layers may be an insulating resin film comprising a cured product of a photosensitive resin composition according to the present disclosure.

[0189] FIG. 2 is a partial cross-sectional view illustrating an example of a semiconductor device having an insulating layer. The semiconductor device (100) shown in FIG. 2 has a semiconductor chip (10) and a wiring portion (20) provided on the semiconductor chip (10). The wiring portion (20) includes a conductor wiring layer (31) connected to the semiconductor chip (10), a surface protection layer (41), a cover coat layer (42), and a conductive ball (50). The semiconductor device (100) may be a semiconductor package having the configuration of a wafer level package (WLP). The surface protection layer (41) and the cover coat layer (42) are stacked in this order from the side of the semiconductor chip (10), and the conductive ball (50) is provided outside the cover coat layer (42). The surface protection layer (41) and the cover coat layer (42) are insulating layers, and either or both of them may be an insulating resin film comprising a cured product of a photosensitive resin composition according to the present disclosure.

[0190] A semiconductor chip (10) has a chip body portion (11) having a circuit surface, a pad portion (12) provided on the circuit surface of the chip body portion (11), and a protective film (13) having a pattern including an opening through which the pad portion (12) is exposed. A conductor wiring layer (31) of a wiring portion (20) is a rewiring layer connected to the pad portion (12) and extends to an inner portion of a conductive ball (50) between a surface protective layer (41) and a cover coat layer (42). A connection portion (32) for connecting to a conductive ball (50) is provided on the end portion of the conductor wiring layer (31). A barrier metal (33) is provided between the connection portion (32) and the conductive ball (50). The pad portion (12), conductor wiring layer (31), connection portion (32), barrier metal (33), and conductive ball (50) are electrically connected in this order.

[0191] A wiring portion (rewiring portion) of a semiconductor device may have a multilayer conductive wiring layer, and an insulating resin film comprising a cured product of a photosensitive resin composition according to the present disclosure may be provided as an interlayer insulating layer provided between adjacent conductive wiring layers. In the semiconductor device, the interlayer insulating layer, the surface protection layer, or both thereof may be an insulating resin film comprising a cured product of a photosensitive resin composition according to the present disclosure.

[0192] The semiconductor device may be a memory. Examples of electronic devices including the semiconductor device according to the present disclosure include mobile phones, smartphones, tablet terminals, computers, and hard disk suspensions.

[0193] Examples

[0194] The present invention is not limited to the following embodiments.

[0195] 1. Raw materials

[0196] (A) Alkali-soluble resin

[0197] A1: Novolak resin having phenolic hydroxyl and imide groups (acid-catalyzed reaction product of bis(o-hydroxy-p-methylphenyl)4,4'-oxyphthalimide and 1,4-bismethoxymethylbenzene, weight average molecular weight: 270,000)

[0198] A2: Novolak resin having phenolic hydroxyl and imide groups (acid-catalyzed reaction product of bis(o-hydroxyphenyl)4,4'-oxyphthalimide and 1,4-bismethoxymethylbenzene, weight average molecular weight: 42000)

[0199] A3: Novolak resin having phenolic hydroxyl and imide groups (acid-catalyzed reaction product of bis(m-hydroxyphenyl)4,4'-oxyphthalimide and 1,4-bismethoxymethylbenzene, weight average molecular weight: 72000)

[0200] A4: Novolak resin having phenolic hydroxyl and imide groups (acid-catalyzed reaction product of bis(o-hydroxy-p-methylphenyl)4,4'-biphthalimide and 1,4-bismethoxymethylbenzene, weight average molecular weight: 13000)

[0201] A5: Novolak resin having phenolic hydroxyl and imide groups (acid-catalyzed reaction product of bis(m-hydroxyphenyl)pyromellitimide, o-cresol and p-cresol, 1,4-bismethoxymethylbenzene and formaldehyde, molar ratio: bis(m-hydroxyphenyl)pyromellitimide / o-cresol / p-cresol / 1,4-bismethoxymethylbenzene / formaldehyde = 10 / 60 / 30 / 30 / 70, weight average molecular weight: 150000)

[0202] A'1: p-hydroxystyrene-styrene copolymer (Molar ratio: p-hydroxystyrene / styrene = 85 / 15, Weight average molecular weight: 10,000, Manufactured by Maruzen Sekiyu Kagaku Co., Ltd., Trade name "CST85")

[0203] (B) Photoinducible

[0204] 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 approx. 63%, manufactured by Daito Chemics Co., Ltd., trade name "PA28"

[0205] B2: 1-naphthoquinone-2-diazide-5-sulfonic acid ester of bis[3-(4-hydroxybenzyl)-4-hydroxy-2,5-dimethylphenyl]methane (esterification rate approx. 75%, manufactured by Toyo Kosei Kogyo Co., Ltd., trade name "CNB300")

[0206] (C) Thermal crosslinking agent

[0207] C1: 4,4'-[1-[4-[1-[4-hydroxy-3,5-bis(methoxymethyl)phenyl]-1-methylethyl]phenyl]ethylidene]bis[2,6-bis(methoxymethyl)phenol](represented by formula (42), and R 40 This methoxymethyl group compound, manufactured by Honshu Kagaku High School Co., Ltd., trade name "HMOM-TPPA"

[0208] C2: 2,2-bis(4-hydroxy-3,5-dimethoxymethyl-phenyl)propane (represented by formula (44), and R 40 This methoxymethyl group compound, manufactured by Asahi Yukizai Co., Ltd., trade name "TMX-BIP"

[0209] (D) Acrylic elastomer

[0210] The following acrylic elastomers D1 to D4 containing monomer units having polyoxyalkylene groups were prepared. For comparison, acrylic elastomer D'1, which does not contain monomer units having oxyalkylene groups, was also prepared. The monomers constituting each acrylic elastomer and the copolymerization ratio (molar ratio) are shown in Table 1.

[0211] D1: Copolymer of 2-(2-ethoxyethoxy)ethyl acrylic acid / acrylic acid / hydroxybutyl acrylate / 1,2,2,6,6-pentamethylpiperidineyl methacrylate = 74 / 17 / 5 / 4 (molar ratio), weight average molecular weight: 10,000, ethyl lactate solution at a concentration of 40 mass%)

[0212] 50 g of ethyl lactate was placed in a 100 mL three-necked flask equipped with a nitrogen inlet tube and a thermometer. To this, 2-(2-ethoxyethoxy)ethyl acrylic acid, acrylic acid, hydroxybutyl acrylate, and 1,2,2,6,6-pentamethylpiperidinyl methacrylate were added as monomers in a molar ratio of 74 / 17 / 5 / 4. The total amount of monomers was 45 g. After heating the mixture in the flask to 80°C, an ethyl lactate solution containing 0.2 g of AIBN was added dropwise. A copolymer of D1 acrylic elastomer was produced by a polymerization reaction for 5 hours while maintaining the temperature in the flask within the range of 80 ± 5°C.

[0213] D2: Copolymer of phenoxydiethylene glycol acrylate / acrylic acid / hydroxybutyl acrylate / 1,2,2,6,6-pentamethylpiperidineyl methacrylate = 74 / 17 / 5 / 4 (molar ratio), weight average molecular weight: 12,000, ethyl lactate solution at a concentration of 40 mass%)

[0214] 50 g of ethyl lactate was placed in a 100 mL three-necked flask equipped with a nitrogen inlet tube and a thermometer. To this, phenoxydiethylene glycol acrylate, acrylic acid, hydroxybutyl acrylate, and 1,2,2,6,6-pentamethylpiperidine yl methacrylate were added as monomers in a molar ratio of 74 / 17 / 5 / 4. The total amount of monomers was 45 g. After heating the mixture in the flask to 80°C, an ethyl lactate solution containing 0.2 g of AIBN was added dropwise. A copolymer of D2 acrylic elastomer was produced by a polymerization reaction for 5 hours while maintaining the temperature in the flask within the range of 80 ± 5°C.

[0215] D3: Copolymer of 2-(2-ethoxyethoxy)ethyl acrylic acid / acrylic acid / N-(2-hydroxyethyl)acrylamide / 1,2,2,6,6-pentamethylpiperidineyl methacrylate = 74 / 17 / 5 / 4 (molar ratio), weight average molecular weight: 9000, ethyl lactate solution at a concentration of 40 mass%)

[0216] 50 g of ethyl lactate was placed in a 100 mL three-necked flask equipped with a nitrogen inlet tube and a thermometer. To this, 2-(2-ethoxyethoxy)ethyl acrylate, acrylic acid, N-(2-hydroxyethyl)acrylamide, and 1,2,2,6,6-pentamethylpiperidine yl methacrylate were added as monomers in a molar ratio of 74 / 17 / 5 / 4. The total amount of monomers was 45 g. After heating the mixture in the flask to 80°C, an ethyl lactate solution containing 0.2 g of AIBN was added dropwise. A copolymer of D3 acrylic elastomer was produced by a polymerization reaction for 5 hours while maintaining the temperature in the flask within the range of 80 ± 5°C.

[0217] D4: Copolymer of 2-(2-ethoxyethoxy)ethyl acrylic acid / β-carboxyethyl acrylate / hydroxybutyl acrylate / 1,2,2,6,6-pentamethylpiperidineyl methacrylate = 74 / 17 / 5 / 4 (molar ratio), weight average molecular weight: 11,000, ethyl lactate solution at a concentration of 40 mass%)

[0218] 50 g of ethyl lactate was placed in a 100 mL three-necked flask equipped with a nitrogen inlet tube and a thermometer. To this, 2-(2-ethoxyethoxy)ethyl acrylate, β-carboxyethyl acrylate, hydroxybutyl acrylate, and 1,2,2,6,6-pentamethylpiperidinyl methacrylate were added as monomers in a molar ratio of 74 / 17 / 5 / 4. The total amount of monomers was 45 g. After heating the mixture in the flask to 80°C, an ethyl lactate solution containing 0.2 g of AIBN was added dropwise. A copolymer of D4 acrylic elastomer was produced by a polymerization reaction for 5 hours while maintaining the temperature in the flask within the range of 80 ± 5°C.

[0219] D5: Copolymer of methoxydipropylene glycol acrylate / phenoxydiethylene glycol acrylate / acrylic acid / hydroxybutyl acrylate / 1,2,2,6,6-pentamethylpiperidineyl methacrylate = 52 / 20 / 18 / 5 / 5 (molar ratio), weight average molecular weight: 8000, ethyl lactate solution at a concentration of 40 mass%)

[0220] 50 g of ethyl lactate was placed in a 100 mL three-necked flask equipped with a nitrogen inlet tube and a thermometer. To this, methoxydipropylene glycol acrylate, phenoxydiethylene glycol acrylate, acrylic acid, hydroxybutyl acrylate, and 1,2,2,6,6-pentamethylpiperidinyl methacrylate were added as monomers in a molar ratio of 52 / 20 / 18 / 5 / 5. The total amount of monomers was 45 g. After heating the mixture in the flask to 80°C, an ethyl lactate solution containing 0.2 g of AIBN was added dropwise. A copolymer of D5 acrylic elastomer was produced by a polymerization reaction for 5 hours while maintaining the temperature in the flask within the range of 80 ± 5°C.

[0221] D'1: Copolymer of butyl acrylate / acrylic acid / hydroxybutyl acrylate / 1,2,2,6,6-pentamethylpiperidineyl methacrylate = 74 / 17 / 5 / 4 (molar ratio), weight average molecular weight: 11,000, ethyl lactate solution at a concentration of 40 mass%)

[0222] [Table 1]

[0223]

[0224] (E) Silane coupling agent

[0225] E1: 3-Glycidyloxypropyltrimethoxysilane (Manufactured by Shin-Etsu Kagaku High School Co., Ltd., Trade name "KBM403")

[0226] 2. Photosensitive resin composition

[0227] Each component was mixed with γ-butyrolactone and ethyl lactate at the mixing ratio (parts by mass) shown in Table 2. The mixture was pressure-filtered through a polytetrafluoroethylene filter with 0.2 μm holes to prepare a photosensitive resin composition.

[0228] 3. Evaluation

[0229] Turbidity of the photosensitive layer

[0230] A photosensitive resin composition was applied onto a silicon substrate by spin coating. The solvent was removed by heating the film at 120°C for 3 minutes to form a photosensitive layer with a thickness of 5 to 6 μm. Subsequently, the photosensitive layer was exposed to the entire wavelength through a mask. After exposure, a photosensitive layer (insulating resin film) having a pattern was formed by developing with an aqueous solution of tetramethylammonium hydroxide (TMAH) at a concentration of 2.38 mass%. The photosensitive layer was observed before and after development, and the turbidity was evaluated according to the following criteria based on the presence or absence of cloudiness.

[0231] A: No cloudiness before and after development

[0232] B: No cloudiness before development, and cloudiness after development.

[0233] C: Cloudiness present before and after development

[0234] Film thickness uniformity

[0235] A photosensitive resin composition was applied onto a silicon substrate by spin coating. The solvent was removed by heating the coating film at 120°C for 3 minutes to form a photosensitive layer with a thickness of 5 to 6 μm. The surface morphology of the photosensitive layer was measured using a stylus-type surface morphology measuring instrument (Alvac Co., Ltd., product name "Dektak 150") under conditions of a measurement width of 4 mm, a travel speed of 5 mm / min, and a sinking load of 15 mg. From the measurement results, the 10-point average roughness Rz was calculated. Based on the average value of Rz obtained from three measurements, the film thickness uniformity was evaluated according to the following criteria. A small Rz value indicates high film thickness uniformity.

[0236] A: 0.01μm or less

[0237] B: Greater than 0.01μm and 0.1μm or less

[0238] C: Larger than 0.1μm

[0239] Resolution

[0240] A photosensitive resin composition was applied onto a silicon substrate by spin coating. The solvent was removed by heating the coating film at 120°C for 3 minutes to form a photosensitive layer with a thickness of 5 to 6 μm. Subsequently, using an i-line stepper (manufactured by Canon, trade name "FPA-3000iW"), the photosensitive layer was projected and exposed to i-lines (365 nm) through a mask having a pattern corresponding to square through-holes having stepwise different sizes in the range of 1 μm × 1 μm to 100 μm × 100 μm. The exposure amount of the i-line was 1000 mJ / cm² 2 ...was. After exposure, a portion of the photosensitive layer was removed by developing with an aqueous solution of tetramethylammonium hydroxide (TMAH) at a concentration of 2.38 mass%. The remaining photosensitive layer, the insulating resin film, was washed with water. The insulating resin film was observed, and the length of one side of the smallest of the formed through holes was recorded as the resolution. A small resolution indicates good resolution.

[0241] Breaking elongation and breaking strength of insulating resin film (cured film)

[0242] A photosensitive resin composition was applied onto a silicon substrate by spin coating. The coating was heated at 120°C for 3 minutes to form a photosensitive layer with a thickness of 8–9 μm. Subsequently, the photosensitive layer was exposed across the entire wavelength range through a mask using an aligner (manufactured by Juice Microtech Co., Ltd., trade name "MA-8"). The exposure dose was 1500 mJ / cm². 2After exposure, an insulating resin film having a pattern including a linear portion with a width of 10 mm was formed by developing with a 2.38% aqueous TMAH solution. The formed insulating resin film was cured by heating it using an inert gas oven (INH-9CD-S) under a nitrogen atmosphere, increasing the temperature to 230°C over 1 hour and maintaining it at 230°C for 2 hours. The thickness of the cured insulating resin film after heating was approximately 7 μm.

[0243] A strip-shaped test specimen with a width of 10 mm was prepared from a cured film peeled from a silicon substrate. Tensile testing of the test specimen was performed using an Autograph AGS-100NX manufactured by Shimadzu Seisakusho Co., Ltd. For the tensile test, the chuck length was 20 mm, the tensile speed was 5 mm / min, and the temperature of the measurement environment was room temperature (20℃~25℃). From the results of the tensile test, the elongation at break and fracture strength of six test specimens obtained from cured films prepared under the same conditions were determined. The maximum values ​​of the elongation at break and fracture strength of the six test specimens are shown in Table 1.

[0244] [Table 2]

[0245]

[0246] As shown in Table 2, the photosensitive resin composition of the example, comprising (A) an alkali-soluble resin having phenolic hydroxyl groups and an imide group, (B) a photogenerator, (C) a thermal crosslinking agent, and (D) an acrylic elastomer having a monomer unit having a polyoxyalkylene group, was confirmed to be able to form an insulating resin film with low turbidity and high mechanical strength and elongation. The photosensitive resin composition of the example was also excellent in terms of film thickness uniformity and resolution. Explanation of the symbols

[0247] 10… semiconductor chip 11… Chip main body 12… pad part 13… shield 20… Wiring section 31… Conductor wiring layer 32… connection part 33… Barrier Metal 41… Surface protection layer (insulation layer) 42… Cover coat layer (insulation layer) 50… challenging ball 100… semiconductor device

Claims

Claim 1 A positive-type photosensitive resin composition comprising (A) an alkali-soluble resin having phenolic hydroxyl groups and imide groups, (B) a photogenerator which is a compound that generates acid upon light, (C) a thermal crosslinking agent which is a compound that crosslinks the alkali-soluble resin upon heat, and (D) an acrylic elastomer which is a polymer comprising monomer units derived from (meth)acrylic acid ester, wherein the acrylic elastomer comprises monomer units having polyoxyalkylene groups. Claim 2 In claim 1, the monomer unit having a polyoxyalkylene group is, the following formula (51): [Chemical Formula 1] It is a monomer unit represented as, and R 50 This represents a hydrogen atom or a methyl group, and R 51 This represents an alkylene group, and R 52 A positive-type photosensitive resin composition in which g represents a hydrocarbon group and n represents an integer of 2 or more. Claim 3 A positive-type photosensitive resin composition according to claim 1, wherein the ratio of the monomer unit having a polyoxyalkylene group is 50 mol% or more based on the total monomer unit in the acrylic elastomer. Claim 4 A positive-type photosensitive resin composition according to claim 1, wherein the acrylic elastomer further comprises a monomer unit having a hydroxyl group. Claim 5 In claim 1, the alkali-soluble resin is, the following formula (I): [Chemical Formula 2] It comprises a constituent unit obtained by removing one or more hydrogen atoms from a bisphenolimide compound represented as, and R 1 This is a hydrogen atom or a carbon-1 to carbon-3 alkyl group, and Z 1 This tetravalent organic, positive-type photosensitive resin composition. Claim 6 A positive-type photosensitive resin composition according to claim 1, wherein the thermal crosslinking agent comprises an alkoxy compound having a plurality of alkoxy groups. Claim 7 A method for forming an insulating resin film, comprising: exposing a portion of a photosensitive layer comprising a positive-type photosensitive resin composition as described in any one of claims 1 to 6; forming an insulating resin film having a pattern including an opening by developing to remove a portion of the photosensitive layer; and heating the insulating resin film. Claim 8 An insulating resin film comprising a cured product of a positive-type photosensitive resin composition described in any one of claims 1 to 6, and having a pattern including an opening. Claim 9 A semiconductor device comprising a semiconductor chip, a conductor wiring layer connected to the semiconductor chip, and one or more insulating layers, wherein at least a portion of the one or more insulating layers is an insulating resin film as described in claim 8.

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