Photosensitive resin composition for forming insulation film

Abstract

This photosensitive resin composition for forming an insulation film comprises: an alkali-insoluble polyimide having a structural unit represented by formula (1) and a structural unit represented by formula (2); a photoradical polymerization initiator; a crosslinkable compound; a thermal radical generator having a one-minute half-life temperature of at least 140℃; and a solvent. (In formula (1), A1 represents a tetravalent organic group. In formula (2), A2 represents a divalent aromatic group having a photopolymerizable group.)

Description

Photosensitive resin composition for forming insulating film

[0001] The present invention relates to a photosensitive resin composition for forming an insulating film, an insulating film obtained from the composition, a photosensitive resist film using the composition, a method for producing a substrate having a cured relief pattern, and a semiconductor device having a cured relief pattern.

[0002] Polyimide resins, which have excellent heat resistance, electrical properties, and mechanical properties, have been used as insulating materials for electronic components and passivation films, surface protective films, interlayer insulating films, etc. for semiconductor devices. Among these polyimide resins, those provided in the form of photosensitive polyimide precursors can easily form heat-resistant relief pattern coatings by applying the precursor, pre-baking, exposing, developing, and curing the precursor for thermal imidization. Such photosensitive polyimide precursors have the advantage of enabling significant process reduction compared to conventional non-photosensitive polyimide resins.

[0003] Patent Documents 1 and 2 propose photosensitive resin compositions containing polyamic acid or polyimide using diamines having (meth)acryloyloxy groups. Furthermore, increasing the thickness and modulus of elasticity of passivation films, surface protection films, interlayer insulating films, etc. of semiconductor devices increases stress, which can lead to greater warpage of semiconductor wafers and problems during transportation and wafer fixation. Therefore, there is a need for the development of polyimide resins with low residual stress. Methods for reducing the residual stress of polyimide resins include, for example, a method of forming a rigid skeleton of the polyimide molecular chain in order to bring the thermal expansion coefficient of the polyimide closer to that of a silicon wafer (see, for example, Patent Document 3).

[0004] JP 2000-347404 Publication Special Table 2012-516927 JP 5-295115

[0005] In the process of forming a heat-resistant relief pattern coating, a lower curing temperature is required. However, lowering the curing temperature tends to deteriorate the thermal properties (e.g., glass transition temperature, thermal expansion coefficient) of the coating. Therefore, there is a need for a photosensitive resin composition for forming an insulating film that can suppress deterioration of the thermal properties of the resulting insulating film even when the curing temperature is lowered.

[0006] In view of the above circumstances, an object of the present invention is to provide a photosensitive resin composition for forming an insulating film that can suppress deterioration of the thermal properties of the resulting insulating film even when the curing temperature is lowered, an insulating film obtained from the composition, a photosensitive resist film using the composition, a method for producing a substrate with a cured relief pattern, and a semiconductor device having a cured relief pattern.

[0007] As a result of extensive research to achieve the above object, the present inventors have found that by adding a specific thermal radical generator to a photosensitive resin composition for forming an insulating film, it is possible to obtain a photosensitive resin composition for forming an insulating film that can suppress deterioration of the thermal properties of the resulting insulating film even when the curing temperature is lowered, and have thus completed the present invention.

[0008] [1] A photosensitive resin composition for forming an insulating film, comprising: an alkali-insoluble polyimide having a structural unit represented by the following formula (1) and a structural unit represented by the following formula (2); a photoradical polymerization initiator; a crosslinkable compound; a thermal radical generator having a one-minute half-life temperature of 140°C or higher; and a solvent. (In formula (1), A １ represents a tetravalent organic group. ２ represents a divalent aromatic group having a photopolymerizable group.) [2] The photosensitive resin composition for forming an insulating film according to [1], wherein the thermal radical generator is a compound represented by the following formula (H1): (In formula (H1), R １ represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and when the alkyl group has 3 or more carbon atoms, it is a branched alkyl group; A ３represents a single bond, a divalent aromatic group or a divalent alicyclic hydrocarbon group, X represents a single bond or a divalent linking group having 1 to 3 carbon atoms, and Z represents a hydrogen atom or a group represented by the following formula (H1-1): ３ and when X is a single bond, R １ represents an alkyl group having 1 to 10 carbon atoms. (In formula (H1-1), R １ , A ３ and X are each defined as in formula (H1), and * represents a bond. １ represents an alkyl group having 1 to 4 carbon atoms; A ３ [4] The photosensitive resin composition for forming an insulating film according to [2], wherein A represents a divalent aromatic group or a divalent alicyclic hydrocarbon group, X represents a divalent linking group having 1 to 3 carbon atoms, and Z represents a hydrogen atom. ３ [5] The photosensitive resin composition for forming an insulating film according to [1], wherein X represents a phenylene group or a cyclohexylene group, and X represents an isopropylidene group. [6] The photosensitive resin composition for forming an insulating film according to [1], wherein X represents a phenylene group or a cyclohexylene group, and X represents an isopropylidene group. (In formula (H2), R ２ each independently represents an alkyl group having 1 to 10 carbon atoms, and when the alkyl group has 3 or more carbon atoms, it is a branched alkyl group; A ４ represents a divalent organic group having 2 to 10 carbon atoms, and each X independently represents a single bond or a divalent linking group having 1 to 3 carbon atoms. [6] In the formula (H2), R ２ represents an alkyl group having 1 to 4 carbon atoms; A ４ [7] The photosensitive resin composition for forming an insulating film according to any one of [1] to [6], wherein X represents a phenylene group or a cyclohexylene group, and X represents an isopropylidene group. [8] The photosensitive resin composition for forming an insulating film according to any one of [1] to [6], wherein the structural unit represented by formula (2) is a structural unit represented by the following formula (2a): (In formula (2a), V １ represents a direct bond, an ether bond, an ester bond, an amide bond, a urethane bond, or a urea bond; W １represents an oxygen atom or an NH group, R ２ represents a direct bond or an alkylene group having 2 to 6 carbon atoms which may be substituted with a hydroxy group, R ３ represents a hydrogen atom or a methyl group.) [8] In the formula (2a), V １ represents an ester bond, W １ [9] The photosensitive resin composition for forming an insulating film according to [7], wherein in the formula (2a), R ２

[10] The photosensitive resin composition for forming an insulating film according to any one of [1] to [9], wherein the structural unit represented by formula (1) is at least one structural unit selected from the group consisting of the following formulas (1a), (1b), and (1c): (In formula (1c), A ４represents a divalent organic group having at least two benzene rings.)

[11] The photosensitive resin composition for forming an insulating film according to any one of [1] to

[10] , further comprising an adhesion promoter.

[12] The photosensitive resin composition for forming an insulating film according to any one of [1] to

[11] , further comprising an azole compound.

[13] An insulating film which is a fired product of a coating film of the photosensitive resin composition for forming an insulating film according to any one of [1] to

[12] .

[14] A photosensitive resist film having a base film, a photosensitive resin layer formed from the photosensitive resin composition for forming an insulating film according to any one of [1] to

[12] , and a cover film.

[15] A method for producing a substrate having a cured relief pattern, comprising: (1) applying the photosensitive resin composition for forming an insulating film according to any one of [1] to

[12] onto a substrate to form a photosensitive resin layer on the substrate; (2) exposing the photosensitive resin layer; (3) developing the exposed photosensitive resin layer to form a relief pattern; and (4) heat-treating the relief pattern to form a cured relief pattern.

[16] A method for producing a substrate having a cured relief pattern according to

[15] , wherein the developer used for the development is an organic solvent.

[17] A substrate having a cured relief pattern produced by the method according to

[15] or

[16] .

[18] A semiconductor device comprising a semiconductor element and a cured film provided on or below the semiconductor element, wherein the cured film has a cured relief pattern formed from the photosensitive resin composition for forming an insulating film according to any one of [1] to

[12] .

[0009] According to the present invention, there are provided a photosensitive resin composition for forming an insulating film that can suppress deterioration of the thermal properties of the resulting insulating film even when the curing temperature is lowered, an insulating film obtained from the composition, a photosensitive resist film using the composition, a method for producing a substrate with a cured relief pattern, and a semiconductor device having a cured relief pattern.

[0010] (Photosensitive Resin Composition for Forming Insulating Film) The photosensitive resin composition for forming an insulating film of the present invention contains at least a polyimide, a photoradical polymerization initiator, a crosslinkable compound, a thermal radical generator having a one-minute half-life temperature of 140°C or higher, and a solvent, and may further contain other components as necessary.

[0011] By including a thermal radical generator in the photosensitive resin composition for forming an insulating film, deterioration of the thermal properties (e.g., glass transition temperature, thermal expansion coefficient) of the resulting insulating film can be suppressed even when the curing temperature is lowered. As a result, an insulating film with good thermal properties can be obtained. Furthermore, when the photosensitive resin composition for forming an insulating film contains a thermal radical generator, a film with higher transmittance and lower dielectric constant can be obtained compared to when the photosensitive resin composition for forming an insulating film does not contain a thermal radical generator. Note that if the one-minute half-life temperature of the thermal radical generator is low, decomposition of the thermal radical generator and radical generation may occur during pre-baking (e.g., pre-baking at about 120°C) when forming an insulating film by coating, pre-baking, exposure, development, and curing, which may result in an inability to obtain a good cured relief pattern. In this regard, the one-minute half-life temperature of the thermal radical generator is 140°C or higher, preferably 160°C or higher, and more preferably 170°C or higher.

[0012] <Polyimide> The polyimide has a structural unit represented by the following formula (1) and a structural unit represented by the following formula (2): Hereinafter, this polyimide may be referred to as a "specific polyimide." (In formula (1), A １ represents a tetravalent organic group. ２ represents a divalent aromatic group having a photopolymerizable group.

[0013] The specific polyimide is preferably alkali-insoluble. That is, the specific polyimide is preferably an alkali-insoluble polyimide. The alkali-insolubility of the alkali-insoluble polyimide means, for example, that an unexposed and uncured film obtained from the photosensitive resin composition for forming an insulating film is not dissolved in an alkali developer (e.g., a 2.38 mass% aqueous solution of TMAH (tetramethylammonium hydroxide)). Insoluble in an alkali developer does not necessarily mean that the polyimide is completely insoluble, but may be slightly soluble in the alkali developer as long as the contrast with the exposed portion that becomes insoluble in the developer is unclear.

[0014] The specific polyimide may further have at least one of a structural unit represented by the following formula (3) and a structural unit represented by the following formula (4). (In formula (3), A １１ represents a divalent aromatic group having an alkyl group having 5 or more carbon atoms. １２ is A in formula (2) ２ , and A in formula (3) １１ A in formula (3) represents a divalent organic group other than １１ is A in formula (2) ２ is a different group from

[0015] <<A in formula (1) １ >> A １ The tetravalent organic group is not particularly limited, but is preferably a tetravalent organic group having two or more aromatic rings, since this reduces the dielectric loss tangent of the insulating film.

[0016] The number of aromatic rings contained in the tetravalent organic group having two or more aromatic rings is not particularly limited as long as it is two or more, and may be, for example, four or more. The upper limit of the number of aromatic rings is not particularly limited, and may be, for example, eight or less, or six or less.

[0017] Regarding the counting of aromatic rings in "two or more aromatic rings," polycyclic aromatic rings formed by the condensation of two or more aromatic rings, such as naphthalene rings and anthracene rings, are counted as one aromatic ring. Therefore, a naphthalene ring is counted as one aromatic ring. On the other hand, a biphenyl ring is counted as two aromatic rings because it is not a condensed ring. Furthermore, a perylene ring is considered to be a structure formed by the condensation of two naphthalene rings, and is counted as two aromatic rings. Examples of aromatic rings include aromatic hydrocarbon rings and aromatic heterocycles.

[0018] A １ is preferably a tetravalent organic group represented by the following formula (1-1). [In formula (1-1), X １ and X ２ are each independently a direct bond, an ether bond (-O-), an ester bond (-COO-), an amide bond (-NHCO-), a urethane bond (-NHCOO-), a urea bond (-NHCONH-), a thioether bond (-S-), or a sulfonyl bond (-SO ２ -) R ａ１ and R ａ２ each independently represents an alkyl group having 1 to 6 carbon atoms which may be substituted. １ represents a direct bond or a divalent organic group represented by the following formula (5-a), (5-b), (5-c), or (5-d). n1 and n2 each independently represent an integer of 0 to 3. R ａ１ If there are multiple R ａ１ may be the same or different. ａ２ If there are multiple R ａ２ may be the same or different. * represents a bond.]

[0019] R in formula (1-1) ａ１ and R ａ２Examples of the optionally substituted alkyl group having 1 to 6 carbon atoms in the formula (I) include alkyl groups having 1 to 6 carbon atoms. Examples of alkyl groups having 1 to 6 carbon atoms include methyl, ethyl, propyl, butyl, pentyl, and hexyl. In this specification, unless otherwise specified, alkyl and alkylene groups may be linear, branched, or cyclic, or may be a combination of two or more of these. Examples of substituents in the optionally substituted alkyl group having 1 to 6 carbon atoms include halogen atoms, hydroxy groups, mercapto groups, carboxy groups, cyano groups, formyl groups, haloformyl groups, sulfo groups, amino groups, nitro groups, nitroso groups, oxo groups, thioxy groups, and alkoxy groups having 1 to 6 carbon atoms. Note that the "1 to 6 carbon atoms" in the "optionally substituted alkyl group having 1 to 6 carbon atoms" refers to the number of carbon atoms in the "alkyl group" excluding the substituent. Furthermore, the number of substituents is not particularly limited.

[0020] [In formula (5-a), R ３ represents an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms; m １ represents an integer of 0 to 4. １ When is 2 or more, R ３ may be the same or different. ２ represents a direct bond or a divalent organic group represented by the following formula (6-a) or (6-b), and R ４ and R ５ each independently represents an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms; m ２ and m ３ Each independently represents an integer of 0 to 4. ２ When is 2 or more, R ４ may be the same or different. ３ When is 2 or more, R ５ may be the same or different. ６represents an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms; m ４ represents an integer of 0 to 6. ４ When is 2 or more, R ６ may be the same or different. ３ represents a divalent organic group represented by the following formula (6-a) or (6-b). * represents a bond.

[0021] [In formula (6-a), R ７ , and R ８ each independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms which may be substituted with a halogen atom. ９ , and R １０ each independently represents an optionally substituted alkylene group having 1 to 6 carbon atoms or an optionally substituted arylene group having 6 to 12 carbon atoms. * represents a bond.]

[0022] Z １ Preferably, Z represents a divalent organic group represented by formula (5-b). ２ In formula (5-b), R preferably represents a direct bond. ４ and R ５ preferably represents a methyl group.

[0023] R ７ and R ８ Examples of the alkyl group having 1 to 6 carbon atoms which may be substituted with a halogen atom in the above formula include an alkyl group having 1 to 6 carbon atoms and a halogenated alkyl group having 1 to 6 carbon atoms. Examples of the alkyl group having 1 to 6 carbon atoms include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, and a hexyl group. Examples of the halogen atom in the halogenated alkyl group having 1 to 6 carbon atoms include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. The halogenation in the halogenated alkyl group having 1 to 6 carbon atoms may be partial or complete.

[0024] R ９and R １０ Examples of the substituent in the optionally substituted alkylene group having 1 to 6 carbon atoms in the formula (I) include a halogen atom, a hydroxy group, a mercapto group, a carboxy group, a cyano group, a formyl group, a haloformyl group, a sulfo group, an amino group, a nitro group, a nitroso group, an oxo group, a thioxy group, and an alkoxy group having 1 to 6 carbon atoms. Examples of the optionally substituted alkylene group having 1 to 6 carbon atoms include an alkylene group having 1 to 6 carbon atoms and a halogenated alkylene group having 1 to 6 carbon atoms. Examples of the alkylene group having 1 to 6 carbon atoms include a methylene group, an ethylene group, a propylene group, and a butylene group. Note that the "1 to 6 carbon atoms" in the "optionally substituted alkylene group having 1 to 6 carbon atoms" refers to the number of carbon atoms in the "alkylene group" excluding the substituent. Furthermore, the number of substituents is not particularly limited.

[0025] R ９ and R １０ Examples of the substituent in the optionally substituted arylene group having 6 to 10 carbon atoms in the formula (I) include a halogen atom, an optionally halogenated alkyl group having 1 to 6 carbon atoms, and an optionally halogenated alkoxy group having 1 to 6 carbon atoms. The halogenation may be partial or complete. Examples of the arylene group include a phenylene group and a naphthylene group. The "6 to 10 carbon atoms" in the "optionally substituted arylene group having 6 to 10 carbon atoms" refers to the number of carbon atoms in the "arylene group" excluding the substituent. The number of substituents is not particularly limited.

[0026] Examples of the divalent organic group represented by formula (6-a) include divalent organic groups represented by the following formulas: In the formula, * represents a bond.

[0027] Examples of the divalent organic group represented by formula (6-b) include divalent organic groups represented by the following formulas: In the formula, R ３１ ~R ３３each independently represents a halogen atom, an alkyl group having 1 to 6 carbon atoms which may be substituted with a halogen atom, or an alkoxy group having 1 to 6 carbon atoms which may be substituted with a halogen atom. n31 represents an integer of 0 to 5. n32 and n33 each independently represent an integer of 0 to 4. R ３１ If there are multiple R ３１ may be the same or different. ３２ If there are multiple R ３２ may be the same or different. ３３ If there are multiple R ３３ may be the same or different. * represents a bond.

[0028] R ３１ ~R ３３ Specific examples of the alkyl group having 1 to 6 carbon atoms which may be substituted with a halogen atom in the formula (I) include an alkyl group having 1 to 6 carbon atoms and a halogenated alkyl group having 1 to 6 carbon atoms. Examples of the alkyl group having 1 to 6 carbon atoms include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, and a hexyl group. Examples of the halogen atom in the halogenated alkyl group having 1 to 6 carbon atoms include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. The halogenation in the halogenated alkyl group having 1 to 6 carbon atoms may be partial or complete. R ３１ ~R ３３ Specific examples of the alkoxy group having 1 to 6 carbon atoms which may be substituted with a halogen atom in the formula (I) include an alkoxy group formed from an alkyl group having 1 to 6 carbon atoms which may be substituted with a halogen atom.

[0029] Examples of the tetravalent organic group having two or more aromatic rings include tetravalent organic groups represented by the following formula: In the formula, * represents a bond.

[0030] A in formula (1) other than a tetravalent organic group having two or more aromatic rings １ Examples of the tetravalent organic group include the following: In the formula, * represents a bond.

[0031] The structural unit represented by formula (1) is preferably at least one structural unit selected from the group consisting of the following formulae (1a), (1b), and (1c): (In formula (1c), A ４ represents a divalent organic group having at least two benzene rings.

[0032] A ４ Examples of the divalent organic group include the divalent organic group represented by the above formula (5-b).

[0033] <<A in formula (2) ２ >> A ２ represents a divalent aromatic group having a photopolymerizable group. Examples of the photopolymerizable group include a radically polymerizable group, a cationic polymerizable group, and an anionic polymerizable group. Among these, the radically polymerizable group is preferred. Examples of the radically polymerizable group include an acryloyl group, a methacryloyl group, a propenyl ether group, a vinyl ether group, and a vinyl group.

[0034] Examples of the aromatic ring in the divalent aromatic group having a photopolymerizable group include a benzene ring, a naphthalene ring, and an anthracene ring.

[0035] The divalent aromatic group having a photopolymerizable group is, for example, a residue obtained by removing two amino groups from an aromatic diamine compound having a photopolymerizable group.

[0036] The structural unit represented by formula (2) is preferably a structural unit represented by the following formula (2a). (In formula (2a), V １ represents a direct bond, an ether bond (—O—), an ester bond (—COO—), an amide bond (—NHCO—), a urethane bond (—NHCOO—), or a urea bond (—NHCONH—), and W １ represents an oxygen atom or an NH group, R ２ represents a direct bond or an alkylene group having 2 to 6 carbon atoms which may be substituted with a hydroxy group, R ３ represents a hydrogen atom or a methyl group.

[0037] In this specification, examples of the alkylene group having 2 to 6 carbon atoms which may be substituted with a hydroxy group include a 1,1-ethylene group, a 1,2-ethylene group, a 1,2-propylene group, a 1,3-propylene group, a 1,4-butylene group, a 1,2-butylene group, a 2,3-butylene group, a 1,2-pentylene group, a 2,4-pentylene group, a 1,2-hexylene group, a 1,2-cyclopropylene group, a 1,2-cyclobutylene group, a 1,3-cyclobutylene group, a 1,2-cyclopentylene group, a 1,2-cyclohexylene group, and alkylene groups in which at least a portion of the hydrogen atoms have been substituted with a hydroxy group (for example, a 2-hydroxy-1,3-propylene group).

[0038] V １ preferably represents an ester bond (—COO—). １ preferably represents an oxygen atom. ２ preferably represents a 1,2-ethylene group.

[0039] A in formula (2) ２ Examples of the group include divalent organic groups represented by the following formula: In the formula, * represents a bond, and the two bonds are located, for example, at meta positions relative to the substituent having the photopolymerizable group.

[0040] <<A in formula (3) １１ >> A １１ represents a divalent aromatic group having an alkyl group having 5 or more carbon atoms. The alkyl group having 5 or more carbon atoms may be directly bonded to the aromatic ring of the divalent aromatic group, or may be bonded via another linking group. The number of carbon atoms in the alkyl group is not particularly limited as long as it is 5 or more, and may be, for example, 40 or less, 35 or less, or 30 or less. The number of carbon atoms in the alkyl group is preferably 8 to 40, more preferably 10 to 35, and particularly preferably 12 to 30. The alkyl group may be linear, branched, or cyclic, or may be a combination of two or more of these.

[0041] The divalent aromatic group having an alkyl group having 5 or more carbon atoms is, for example, a residue obtained by removing two amino groups from an aromatic diamine compound having an alkyl group having 5 or more carbon atoms.

[0042] A １１ is preferably a divalent aromatic group represented by any one of formulas (V-1) to (V-6). (In formula (V-1), X ｖ１ is -O-, -CH ２ —O—, —CH ２ represents —OCO—, —COO—, or —OCO—. ｖ１ represents an alkyl group having 5 to 20 carbon atoms. ｖ２ ~X ｖ５ are each independently -(CH ２ ) ａ -(a is an integer of 1 to 15), -CONH-, -NHCO-, -CON(CH ３ )-, -NH-, -O-, -CH ２ —O—, —CH ２ represents —OCO—, —COO—, or —OCO—. ｖ２ ~R ｖ５ each independently represents an alkyl group having 5 to 20 carbon atoms. ａ represents a single bond, —O—, —NH—, —O—(CH ２ ) ｍ -O- (m represents an integer of 1 to 6), -C(CH ３ ) ２ -, -CO-, -(CH ２ ) ｍ - (m represents an integer of 1 to 6), -SO ２ -, -O-C(CH ３ ) ２ -, -CO-(CH ２ ) ｍ - (m represents an integer of 1 to 6), -NH-(CH ２ ) ｍ - (m represents an integer of 1 to 6), -SO ２ - (CH ２ ) ｍ -(m represents an integer of 1 to 6), -CONH-(CH ２ ) ｍ-(m represents an integer of 1 to 6), -CONH-(CH ２ ) ｍ -NHCO- (m represents an integer of 1 to 6), -COO-(CH ２ ) ｍ -OCO- (m represents an integer of 1 to 6), -CONH-, -NH-(CH ２ ) ｍ -NH- (where m represents an integer of 1 to 6), or -SO ２ - (CH ２ ) ｍ -SO ２ - (where m represents an integer of 1 to 6). X ｐ１ and X ｐ２ are each independently -(CH ２ ) ａ -(a is an integer of 1 to 15), -CONH-, -NHCO-, -CON(CH ３ )-, -NH-, -O-, -CH ２ —O—, —CH ２ represents —OCO—, —COO—, or —OCO—. １ａ and R １ｂ each independently represents an alkyl group having 5 to 20 carbon atoms; k1 and k2 each independently represent an integer of 0 to 2; and in formulas (V-1) to (V-6), * represents a bond.

[0043] X ｖ１ ~X ｖ５ is preferably —O—. ｐ１ and X ｐ２ As the group, -CH ２ It is preferable that X represents —O—. ａ It is preferable that represents a single bond.

[0044] A １１ Examples of the divalent aromatic group include the following: * represents a bond.

[0045] <<A in formula (4) １２ >> A １２ As for A in formula (2), ２ , and A in formula (3) １１It represents a divalent organic group other than. As such a divalent organic group, for example, a divalent organic group having three or more aromatic rings is preferable in that a lower dielectric tangent can be obtained in the resulting insulating film. The divalent organic group having three or more aromatic rings is, for example, a residue obtained by removing two amino groups from an aromatic diamine compound having three or more aromatic rings.

[0046] The number of aromatic rings in a divalent organic group having three or more aromatic rings is not particularly limited as long as it is three or more, and may be, for example, four or more. The upper limit of the number of aromatic rings is not particularly limited, and may be, for example, eight or less, or six or less.

[0047] The divalent organic group having three or more aromatic rings is not particularly limited, but is preferably a divalent organic group represented by the following formula (4-1). [In formula (4-1), X ２１ and X ２２ are each independently a direct bond, an ether bond (-O-), an ester bond (-COO-), an amide bond (-NHCO-), a urethane bond (-NHCOO-), a urea bond (-NHCONH-), a thioether bond (-S-), or a sulfonyl bond (-SO ２ -) R ２１ and R ２２ Y each independently represents an alkyl group having 1 to 6 carbon atoms which may be substituted. ２０ represents a divalent organic group represented by the above formula (5-a), (5-b), or (5-c). n21 and n22 each independently represent an integer of 0 to 4. R ２１ If there are multiple R ２１ may be the same or different. ２２ If there are multiple R ２２ may be the same or different. * represents a bond.]

[0048] R in formula (4-1) ２１ and R ２２Examples of the optionally substituted alkyl group having 1 to 6 carbon atoms in the formula (I) include alkyl groups having 1 to 6 carbon atoms. Examples of alkyl groups having 1 to 6 carbon atoms include methyl, ethyl, propyl, butyl, pentyl, and hexyl. In this specification, unless otherwise specified, alkyl and alkylene groups may be linear, branched, or cyclic, or may be a combination of two or more of these. Examples of substituents in the optionally substituted alkyl group having 1 to 6 carbon atoms include halogen atoms, hydroxy groups, mercapto groups, carboxy groups, cyano groups, formyl groups, haloformyl groups, sulfo groups, amino groups, nitro groups, nitroso groups, oxo groups, thioxy groups, and alkoxy groups having 1 to 6 carbon atoms. Note that the "1 to 6 carbon atoms" in the "optionally substituted alkyl group having 1 to 6 carbon atoms" refers to the number of carbon atoms in the "alkyl group" excluding the substituent. Furthermore, the number of substituents is not particularly limited.

[0049] Examples of the divalent organic group having three or more aromatic rings include divalent organic groups represented by the following formula: In the formula, * represents a bond.

[0050] A １２ Examples of other divalent organic groups include divalent organic groups represented by the following formulas: These divalent organic groups are, for example, residues obtained by removing two amino groups from a diamine. In the formula, * represents a bond.

[0051] The polyimide is, for example, an imidized product of polyamic acid, which is a reaction product of a diamine component and a tetracarboxylic acid derivative. The imidization rate of the polyimide does not need to be 100%. The imidization rate of the polyimide may be, for example, 90% or more, 95% or more, or 98% or more.

[0052] Here, examples of the tetracarboxylic acid derivative include tetracarboxylic acid, tetracarboxylic acid diester, tetracarboxylic acid dihalide, and tetracarboxylic acid dianhydride.

[0053] The structural unit represented by formula (1) in the specific polyimide is derived from, for example, an acid dianhydride represented by formula (1A) below. The structural unit represented by formula (2) in the specific polyimide is derived from, for example, a diamine represented by formula (2A) below. The structural unit represented by formula (3) in the specific polyimide is derived from, for example, a diamine represented by formula (3A) below. The structural unit represented by formula (4) in the specific polyimide is derived from, for example, a diamine represented by formula (4A) below. (In formula (1A), A １ is A in formula (1) １ In formula (2A), A ２ is A in formula (2) ２ In formula (3A), A １１ is A in formula (3) １１ In formula (4A), A １２ is A in formula (4) １２ is synonymous with

[0054] The ratio of the aromatic tetracarboxylic acid derivative having two or more aromatic rings to the total tetracarboxylic acid derivatives constituting the polyimide is not particularly limited, but is preferably 20 mol % to 100 mol %, more preferably 40 mol % to 100 mol %.

[0055] The ratio of the aromatic diamine compound having a photopolymerizable group to all diamine components constituting the polyimide is not particularly limited, but from the viewpoint of obtaining sufficient photosensitivity, it is preferably 10 mol % to 90 mol %, more preferably 15 mol % to 85 mol %, and particularly preferably 20 mol % to 80 mol %.

[0056] The ratio of the aromatic diamine compound having an alkyl group having 5 or more carbon atoms to all diamine components constituting the polyimide is not particularly limited, but is preferably 5 mol % to 80 mol %, more preferably 10 mol % to 70 mol %, and particularly preferably 15 mol % to 65 mol %.

[0057] In the polyimide, the molar ratio (A:B) of the aromatic diamine compound (A) having a photopolymerizable group to the aromatic diamine compound (B) having an alkyl group having 5 or more carbon atoms is not particularly limited, but is preferably 3:1 to 0.3:1, more preferably 2:1 to 0.5:1, and particularly preferably 1.5:1 to 0.5:1.

[0058] The total molar ratio of the aromatic diamine compound having a photopolymerizable group and the aromatic diamine compound having an alkyl group having 5 or more carbon atoms to the total diamine components constituting the polyimide is not particularly limited, but is preferably 30 mol% or more, more preferably 40 mol% or more, and particularly preferably 50 mol% or more. The upper limit of the total molar ratio is not particularly limited, but the total molar ratio may be 100 mol% or less, or may be 90 mol% or less.

[0059] The weight-average molecular weight of the specific polyimide is not particularly limited, but the weight-average molecular weight measured in terms of polyethylene oxide by gel permeation chromatography (hereinafter abbreviated as GPC in this specification) is preferably 5,000 to 100,000, more preferably 7,000 to 50,000, still more preferably 10,000 to 50,000, and particularly preferably 10,000 to 40,000.

[0060] <<Method for Producing Specific Polyimide>> The method for producing the specific polyimide is not particularly limited, and for example, the specific polyimide can be obtained by imidizing polyamic acid. Polyamic acid and the specific polyimide can be synthesized by known methods such as those described in WO2013 / 157586.

[0061] The polyamic acid is produced, for example, by reacting a diamine component with a tetracarboxylic acid derivative in a solvent (condensation polymerization).

[0062] Specific examples of the solvent include N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, γ-butyrolactone, N,N-dimethylformamide, N,N-dimethylacetamide, N,N-dimethylpropionamide, N,N-dimethylisobutyric acid amide, dimethyl sulfoxide, and 1,3-dimethyl-2-imidazolidinone. When the polymer has high solubility in the solvent, methyl ethyl ketone, cyclohexanone, cyclopentanone, 4-hydroxy-4-methyl-2-pentanone, or solvents represented by the following formulas [D-1] to [D-3] can be used. (In formula [D-1], D １ represents an alkyl group having 1 to 3 carbon atoms, and in formula [D-2], D ２ represents an alkyl group having 1 to 3 carbon atoms, and in formula [D-3], D ３ represents an alkyl group having 1 to 4 carbon atoms.

[0063] These solvents may be used alone or in combination. Furthermore, even if a solvent does not dissolve polyamic acid, it may be mixed with the above-mentioned solvents to the extent that the polyamic acid does not precipitate.

[0064] When reacting the diamine component and the tetracarboxylic acid derivative in a solvent, the reaction can be carried out at any concentration, preferably 1% by mass to 50% by mass, and more preferably 5% by mass to 30% by mass. The reaction can be carried out at a high concentration initially, with additional solvent added later. In the reaction, the ratio of the total number of moles of the diamine component to the total number of moles of the tetracarboxylic acid derivative is preferably 0.8 to 1.2. As with a typical condensation polymerization reaction, the closer this molar ratio is to 1.0, the higher the molecular weight of the polyamic acid produced.

[0065] When reacting a diamine component with a tetracarboxylic acid derivative, a thermal polymerization inhibitor may be added to the reaction system to prevent polymerization of the photopolymerizable group. Examples of thermal polymerization inhibitors include hydroquinone, 4-methoxyphenol, N-nitrosodiphenylamine, p-tert-butylcatechol, phenothiazine, N-phenylnaphthylamine, ethylenediaminetetraacetic acid, 1,2-cyclohexanediaminetetraacetic acid, glycol ether diaminetetraacetic acid, 2,6-di-tert-butyl-p-cresol, 5-nitroso-8-hydroxyquinoline, 1-nitroso-2-naphthol, 2-nitroso-1-naphthol, 2-nitroso-5-(N-ethyl-N-sulfopropylamino)phenol, N-nitroso-N-phenylhydroxylamine ammonium salt, and N-nitroso-N(1-naphthyl)hydroxylamine ammonium salt. The amount of the thermal polymerization inhibitor used is not particularly limited.

[0066] Polyimide can be obtained by dehydrating and cyclizing the polyamic acid obtained by the above reaction. Methods for obtaining polyimide include thermal imidization, in which the solution of polyamic acid obtained by the above reaction is heated as is, and chemical imidization, in which a catalyst is added to the polyamic acid solution. When thermal imidization is performed in solution, the temperature is 100°C to 400°C, preferably 120°C to 250°C, and it is preferable to perform the imidization while removing water generated by the imidization reaction from the system.

[0067] The chemical imidization can be carried out by adding a basic catalyst and an acid anhydride to a solution of the polyamic acid obtained by the reaction and stirring the mixture at temperatures ranging from -20°C to 250°C, preferably from 0°C to 180°C. The amount of the basic catalyst is 0.1 to 30 times, preferably 0.2 to 20 times, the molar ratio of the amic acid groups, and the amount of the acid anhydride is 1 to 50 times, preferably 1.5 to 30 times, the molar ratio of the amic acid groups. Examples of basic catalysts include pyridine, triethylamine, trimethylamine, tributylamine, and trioctylamine. Of these, triethylamine is preferred because it is less likely to produce polyisoimide as a by-product. Examples of acid anhydrides include acetic anhydride, trimellitic anhydride, and pyromellitic anhydride. Of these, acetic anhydride is preferred because it facilitates purification after the reaction. The imidization rate (the ratio of repeating units that are ring-closed to all repeating units in the polyimide precursor, also referred to as the ring-closure rate) in chemical imidization can be controlled by adjusting the amount of catalyst, reaction temperature, and reaction time.

[0068] When recovering the imidized product produced from the imidization reaction solution, the reaction solution may be poured into a solvent to cause precipitation. Examples of solvents used for precipitation include methanol, ethanol, isopropyl alcohol, acetone, hexane, butyl cellosolve, heptane, methyl ethyl ketone, methyl isobutyl ketone, toluene, benzene, and water. The polymer precipitated by pouring into the solvent can be recovered by filtration and then dried at room temperature or by heating under normal or reduced pressure.

[0069] The specific polyimide may be end-capped. The method for end-capping is not particularly limited, and for example, a conventionally known method using a monoamine or an acid anhydride can be used.

[0070] The content of the specific polyimide in the photosensitive resin composition for forming an insulating film is not particularly limited, but is preferably 50 to 90 parts by mass, more preferably 55 to 85 parts by mass, still more preferably 60 to 80 parts by mass, and particularly preferably 65 to 75 parts by mass, relative to 100 parts by mass of the film-constituting components. The film-constituting components refer to components other than the solvent in the photosensitive resin composition for forming an insulating film.

[0071] <Thermal Radical Generator> The thermal radical generator has a one-minute half-life temperature of 140° C. or higher, preferably 160° C. or higher, and more preferably 170° C. or higher. There are no particular limitations on the upper limit of the one-minute half-life temperature of the thermal radical generator, but for example, the one-minute half-life temperature may be 270° C. or lower, 230° C. or lower, or 200° C. or lower.

[0072] The one-minute half-life temperature refers to the temperature at which a thermal radical generator decomposes and its remaining amount is reduced to half in one minute. The one-minute half-life temperature is determined by dissolving the thermal radical generator in a radical-inert solvent, such as benzene, toluene, or ethyl acetate, to form a dilute solution with a concentration of 0.05 mol / L to 0.2 mol / L, and then thermally decomposing the resulting thermal radical generator solution under a nitrogen atmosphere. The one-minute half-life temperature can be measured, for example, by the following method. This method is described in "2. Half-Life and Activation Energy" under "3. Selection of Organic Peroxides" in the NOF Corporation product catalog "Organic Peroxides (10th Edition)." [Method for Measuring the One-Minute Half-Life Temperature] A 0.1 mol / L thermal radical generator solution is prepared using benzene and sealed in a nitrogen-purged glass ampoule. This solution is immersed in an oil bath set to a predetermined temperature (measured at three points around the 10-hour half-life temperature), and the thermal radical generator in the solution is thermally decomposed. Generally, the decomposition of a thermal radical generator in a diluted solution can be treated approximately as a first-order reaction, so the following equations (1) and (2) hold when the amount of thermal radical generator decomposed (x), the decomposition rate constant (k), the time (t), and the initial concentration of the thermal radical generator (a) are used. dx / dt=k(ax) (1) ln a / (ax)=kt (2) Furthermore, the half-life is the time it takes for the concentration of the thermal radical generator to decrease to half of its initial value due to decomposition, so the half-life can be expressed as (t １／２ ) and by substituting (a / 2) for (x) in equation (2), it can be expressed as the following equation (3). １／２ = ln(2)...(3) Therefore, if a thermal radical generator is thermally decomposed at a certain temperature, and the relationship between time (t) and ln[(a) / (ax)] is plotted, and the decomposition rate constant (k) is calculated from the slope of the obtained line, the half-life (t) at that temperature can be calculated from equation (3). １／２ Then, the thermal decomposition is carried out at several temperatures, and the half-life (t １／２ ) and measure ln(t １／２The relationship between (1 / T) and (1 / T) is plotted, and the temperature at which the one-minute half-life occurs can be determined from the resulting straight line. When the thermal radical generator is a commercially available product, the one-minute half-life temperature listed in the product catalog can be used as the one-minute half-life temperature in the present invention.

[0073] The thermal radical generator is not particularly limited, but is preferably an organic peroxide. The organic peroxide is not particularly limited as long as it has an —O—O— bond, but from the viewpoint of suitably obtaining the effects of the present invention, a compound represented by the following formula (H1) is preferred. (In formula (H1), R １ represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and when the alkyl group has 3 or more carbon atoms, it is a branched alkyl group; A ３ represents a single bond, a divalent aromatic group or a divalent alicyclic hydrocarbon group, X represents a single bond or a divalent linking group having 1 to 3 carbon atoms, and Z represents a hydrogen atom or a group represented by the following formula (H1-1): ３ and when X is a single bond, R １ represents an alkyl group having 1 to 10 carbon atoms. (In formula (H1-1), R １ , A ３ and X are each defined as in formula (H1), and * represents a bond.

[0074] R １ The alkyl group having 1 to 10 carbon atoms in the formula (I) is a branched alkyl group when the alkyl group has 3 or more carbon atoms. The alkyl group having 1 to 10 carbon atoms may be, for example, a branched alkyl group having 4 to 10 carbon atoms, or an alkyl group having 1 to 4 carbon atoms.

[0075] A ３ The divalent aromatic group in may be a divalent aromatic hydrocarbon group or a divalent aromatic heterocyclic group, but from the viewpoint of suitably achieving the effects of the present invention, a divalent aromatic hydrocarbon group is preferred, and a phenylene group is more preferred. ３The divalent alicyclic hydrocarbon group in may be a divalent saturated alicyclic hydrocarbon group or a divalent unsaturated alicyclic hydrocarbon group, but from the viewpoint of suitably obtaining the effects of the present invention, a divalent saturated alicyclic hydrocarbon group is preferred, a monocyclic divalent hydrocarbon group having 5 to 7 carbon atoms is more preferred, and a cyclohexylene group is particularly preferred.

[0076] X is, for example, a divalent alkylene group having 1 to 3 carbon atoms, and is preferably an isopropylidene group from the viewpoint of suitably achieving the effects of the present invention.

[0077] R in formula (H1) １ and R in formula (H1-1) １ and may be the same or different, but are preferably the same. ３ and A in formula (H1-1) ３ and may be the same or different, but are preferably the same. X in formula (H1) and X in formula (H1-1) may be the same or different, but are preferably the same.

[0078] A in formula (H1) ３ As a combination of A and X, from the viewpoint of suitably obtaining the effects of the present invention, ３ Preferably, represents a phenylene group or a cyclohexylene group, and X represents an isopropylidene group.

[0079] R in formula (H1) １ and A ３ As a combination of X and Z, R is excellent in terms of ease of handling. １ represents an alkyl group having 1 to 4 carbon atoms; A ３ It is preferred that X represents a divalent aromatic group or a divalent alicyclic hydrocarbon group, X represents a divalent linking group having 1 to 3 carbon atoms, and Z represents a hydrogen atom.

[0080] A ３ is a divalent aromatic group or a divalent alicyclic hydrocarbon group, X is preferably a divalent linking group having 1 to 3 carbon atoms, and more preferably a divalent alkylene group having 1 to 3 carbon atoms.

[0081] A ３When A is a single bond, X is preferably a single bond. ３ and when X is a single bond, R １ is an alkyl group having 1 to 10 carbon atoms, and is preferably a branched alkyl group having 4 to 10 carbon atoms.

[0082] As the organic peroxide, a compound represented by the following formula (H2) having two —O—O— bonds in one molecule is also preferred. (In formula (H2), R ２ each independently represents an alkyl group having 1 to 10 carbon atoms, and when the alkyl group has 3 or more carbon atoms, it is a branched alkyl group; A ４ represents a divalent organic group having 2 to 10 carbon atoms, and each X independently represents a single bond or a divalent linking group having 1 to 3 carbon atoms.

[0083] R ２ The alkyl group having 1 to 10 carbon atoms in the formula (I) is a branched alkyl group when the alkyl group has 3 or more carbon atoms. The alkyl group having 1 to 10 carbon atoms may be, for example, a branched alkyl group having 4 to 10 carbon atoms, or an alkyl group having 1 to 4 carbon atoms.

[0084] A ４ The divalent organic group having 2 to 10 carbon atoms in may be a divalent aromatic hydrocarbon group, a divalent saturated alicyclic hydrocarbon group, a divalent unsaturated alicyclic hydrocarbon group, or a divalent aliphatic group which may have an ester bond or an ether bond. From the viewpoint of suitably achieving the effects of the present invention, a divalent aromatic hydrocarbon group is preferred, and a phenylene group is more preferred.

[0085] X is, for example, a divalent alkylene group having 1 to 3 carbon atoms, and is preferably an isopropylidene group from the viewpoint of suitably achieving the effects of the present invention.

[0086] A in formula (H2) ４ As a combination of A and X, from the viewpoint of suitably obtaining the effects of the present invention, ４ Preferably, represents a phenylene group and X represents an isopropylidene group.

[0087] As the thermal radical generator, a thermal radical generator classified as a Class 4 hazardous material under the Fire Service Act is preferred because of its ease of handling, but a thermal radical generator classified as a Class 5 hazardous material under the Fire Service Act can also be used if handled with sufficient care.

[0088] Commercially available products can be used as the thermal radical generator. Examples of commercially available products include the following. Among these commercially available products, Percumyl (registered trademark) P and Permenta (registered trademark) H are classified as Class 4 hazardous materials under the Fire Service Act. Percumyl (registered trademark) D: dicumyl peroxide, manufactured by NOF Corporation, 1-minute half-life temperature: 175.2°C Percumyl (registered trademark) P: diisopropylbenzene hydroperoxide, manufactured by NOF Corporation, 1-minute half-life temperature: 232.5°C Percumyl (registered trademark) H: cumene hydroperoxide, manufactured by NOF Corporation, 1-minute half-life temperature: 254.0°C Permenta (registered trademark) H: p-menthane hydroperoxide, manufactured by NOF Corporation, 1-minute half-life temperature: 199.5°C Perocta (registered trademark) H: 1,1,3,3-tetramethylbutyl hydroperoxide, manufactured by NOF Corporation, 1-minute half-life temperature: 246.6°C Perbutyl (registered trademark) C: tert-butylcumyl peroxide, manufactured by NOF Corporation, 1-minute half-life temperature: 173.3°C Perbutyl (registered trademark) D: di-tert-butyl peroxide, manufactured by NOF Corporation, 1-minute half-life temperature: 185.9°C Perbutyl (registered trademark) H: tert-butyl hydroperoxide, manufactured by NOF Corporation, 1-minute half-life temperature: 260.7°C Perhexyl (registered trademark) D: di-tert-hexyl peroxide, manufactured by NOF Corporation, 1-minute half-life temperature: 176.7°C Perbutyl (registered trademark) P: α,α-di(tert-butylperoxy)diisopropylbenzene, manufactured by NOF Corporation, 1-minute half-life temperature: 175.4°C Perhexa (registered trademark) 25B: 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane, manufactured by NOF Corporation, 1-minute half-life temperature: 179.8°C Perhexa (registered trademark) V: n-butyl-4,4-di(tert-butylperoxy)valerate, manufactured by NOF Corporation, 1-minute half-life temperature: 172.5°C Perhexa (registered trademark) HC: 1,1-di(tert-hexylperoxy)cyclohexane, manufactured by NOF Corporation, 1-minute half-life temperature: 149.2°C

[0089] Examples of the structure of the thermal radical generator are as follows:

[0090] The content of the thermal radical generator is not particularly limited, but from the viewpoint of suppressing deterioration of thermal properties due to a decrease in the cure temperature, it is preferably 0.1 parts by mass to 20 parts by mass, and more preferably 0.5 parts by mass to 15 parts by mass, per 100 parts by mass of the specific polyimide.

[0091] <Photoradical Polymerization Initiator> The photoradical polymerization initiator (also referred to as "photoradical initiator") is not particularly limited as long as it is a compound that absorbs light from a light source used for photocuring. Examples thereof include tert-butylperoxy-iso-butylate, 2,5-dimethyl-2,5-bis(benzoyldioxy)hexane, 1,4-bis[α-(tert-butyldioxy)-iso-propoxy]benzene, di-tert-butylperoxide, 2,5-dimethyl-2,5-bis(tert-butyldioxy)hexene hydroperoxide, α-(iso-propylphenyl)-iso-propyl hydroperoxide, tert-butyl hydroperoxide, 1,1-bis(tert-butyldioxy)-3,3,5-trimethylcyclohexane, butyl-4,4-bis(tert-butyldioxy)valerate, cyclohexanone peroxide, 2,2',5,5'-tetra(tert organic peroxides such as 3,3'-bis(tert-butylperoxycarbonyl)benzophenone, 3,3',4,4'-tetra(tert-butylperoxycarbonyl)benzophenone, 3,3',4,4'-tetra(tert-amylperoxycarbonyl)benzophenone, 3,3',4,4'-tetra(tert-hexylperoxycarbonyl)benzophenone, 3,3'-bis(tert-butylperoxycarbonyl)-4,4'-dicarboxybenzophenone, tert-butylperoxybenzoate, di-tert-butyldiperoxyisophthalate; quinones such as 9,10-anthraquinone, 1-chloroanthraquinone, 2-chloroanthraquinone, octamethylanthraquinone, 1,2-benzanthraquinone; benzoin derivatives such as benzoin methyl ether, benzoin ethyl ether, α-methylbenzoin, and α-phenylbenzoin;2,2-Dimethoxy-1,2-diphenylethan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propan-1-one, 2-hydroxy-1-[4-{4-(2-hydroxy-2-methyl-propionyl)benzyl}-phenyl]-2-methyl-propan-1-one, phenylglyoxylic acid methyl ester, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)phenyl alkylphenone compounds such as bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide and 2,4,6-trimethylbenzoyldiphenylphosphine oxide; and oxime ester compounds such as 2-(O-benzoyloxime)-1-[4-(phenylthio)phenyl]-1,2-octanedione and 1-(O-acetyloxime)-1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]ethanone. From the viewpoint of i-ray curability, oxime ester compounds are particularly preferred.

[0092] The photoradical polymerization initiator is commercially available, for example, IRGACURE (registered trademark) 651, 184, 2959, 127, 907, 369, 379EG, 819, 819DW, 1800, 1870, 784, OXE01, OXE02, OXE03, OXE04, 250, 1173, MBF, TPO, 4265, TPO (all manufactured by BASF), KAYACURE (registered trademark) DETX-S, MBP, DMBI, EPA, OA (all manufactured by Nippon Kayaku Co., Ltd.), VICURE-10, VICURE-55 (all manufactured by Stauffer Co., Ltd.), ESACURE Examples of such photo-radical polymerization initiators include KIP150, TZT, 1001, KTO46, KB1, KL200, KS300, EB3, Triazine-PMS, Triazine A, and Triazine B (all manufactured by Nippon SiberHegner Co., Ltd.), ADEKA OPTOMER N-1717, N-1414, and N-1606, ADEKA ARCLES (registered trademark) N-1919T, NCI-831E, NCI-930, and NCI-730 (all manufactured by ADEKA Corporation). These photo-radical polymerization initiators may be used alone or in combination of two or more.

[0093] The content of the photoradical polymerization initiator is not particularly limited, but is preferably 0.1 to 20 parts by mass relative to 100 parts by mass of the specific polyimide, and more preferably 0.5 to 15 parts by mass from the viewpoint of photosensitivity characteristics. When the photoradical polymerization initiator is contained in an amount of 0.1 part by mass or more relative to 100 parts by mass of the specific polyimide, the photosensitivity of the insulating film-forming photosensitive resin composition is likely to be improved, while when the photoradical polymerization initiator is contained in an amount of 20 parts by mass or less, the thick-film curability of the insulating film-forming photosensitive resin composition is likely to be improved.

[0094] <Crosslinkable Compound> In order to improve the resolution of the relief pattern, a monomer having a photoradical polymerizable unsaturated bond (crosslinkable compound (also referred to as a "crosslinking agent")) is contained in the photosensitive resin composition for forming an insulating film. Such a crosslinkable compound is preferably a compound containing a polymerizable group that undergoes a radical polymerization reaction in the presence of a photoradical polymerization initiator, and examples of such a crosslinkable compound include (meth)acrylic compounds and maleimide compounds, but are not particularly limited to the following.Examples of the (meth)acrylic compound include diethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, ethylene glycol or polyethylene glycol mono- or di(meth)acrylate, propylene glycol or polypropylene glycol mono- or di(meth)acrylate, glycerol mono-, di-, or tri(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, cyclohexane di(meth)acrylate, cyclohexanedimethanol di(meth)acrylate, tricyclodecane dimethanol di(meth)acrylate, dioxane glycol di(meth)acrylate, bisphenol A mono- or di(meth)acrylate, bisphenol F di(meth)acrylate, hydrogenated bisphenol A di(meth)acrylate, (meth)acrylate, benzene trimethacrylate, di(meth)acrylate of 9,9-bis[4-(2-hydroxyethoxy)phenyl]fluorene, di(meth)acrylate of tris(2-hydroxyethyl)isocyanurate, isobornyl (meth)acrylate, acrylamide and its derivatives, methacrylamide and its derivatives, trimethylolpropane tri(meth)acrylate, di- or tri(meth)acrylate of glycerol, di-, tri-, or tetra(meth)acrylate of pentaerythritol Examples of such compounds include (meth)acrylates, and ethylene oxide or propylene oxide adducts of these compounds, 2-isocyanate ethyl (meth)acrylate or isocyanate-containing (meth)acrylates, and compounds obtained by adding a blocking agent such as methyl ethyl ketone oxime, ε-caprolactam, γ-caprolactam, 3,5-dimethylpyrazole, diethyl malonate, ethanol, isopropanol, n-butanol, or 1-methoxy-2-propanol to these compounds.Examples of maleimide compounds include 1,2-bis(maleimido)ethane, 1,4-bis(maleimido)butane, 1,6-bis(maleimido)hexane, N,N'-1,4-phenylenebismaleimide, N,N'-1,3-phenylenedimaleimide, 4,4'-bismaleimidodiphenylmethane, bis(3-ethyl-5-methyl-4-maleimidophenyl)methane, bis(2-maleimidoethyl)disulfide, 2,2-bis[4-(4-maleimidophenoxy)phenyl]propane, and 1,6'-bismaleimido-(2,2,4-trimethyl)hexane. Examples of commercially available maleimide compounds include BMI-689, BMI-1500, BMI-1700, and BMI-3000 (all manufactured by Designer Molecules Inc.). These compounds may be used alone or in combination of two or more. In this specification, (meth)acrylate means acrylate and methacrylate.

[0095] The content of the crosslinkable compound is not particularly limited, but is preferably 1 to 100 parts by mass, and more preferably 1 to 50 parts by mass, per 100 parts by mass of the specific polyimide.

[0096] <Solvent> As the solvent contained in the photosensitive resin composition for forming an insulating film, it is preferable to use an organic solvent from the viewpoint of the solubility of a specific polyimide. Specific examples of the solvent include N,N-dimethylformamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-dimethylpropionamide, N,N-dimethylisobutyric acid amide, dimethyl sulfoxide, diethylene glycol dimethyl ether, cyclopentanone, cyclohexanone, γ-butyrolactone, α-acetyl-γ-butyrolactone, tetramethylurea, 1,3-dimethyl-2-imidazolinone, N-cyclohexyl-2-pyrrolidone, propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, methyl 2-hydroxyisobutyrate, ethyl lactate, and solvents represented by the following formulas [D-1] to [D-3]. These may be used alone or in combination of two or more. (In formula [D-1], D １ represents an alkyl group having 1 to 3 carbon atoms, and in formula [D-2], D ２ represents an alkyl group having 1 to 3 carbon atoms, and in formula [D-3], D ３ represents an alkyl group having 1 to 4 carbon atoms.

[0097] The solvent can be used in an amount ranging from 30 parts by mass to 1,500 parts by mass, preferably from 100 parts by mass to 1,000 parts by mass, relative to 100 parts by mass of the specific polyimide, depending on the desired coating film thickness and viscosity of the photosensitive resin composition for forming an insulating film.

[0098] <Other Components> In an embodiment, the photosensitive resin composition for forming an insulating film may further contain other components in addition to the specific polyimide, photoradical initiator, crosslinkable compound, thermal radical generator, and solvent. Examples of other components include a heat curing agent, other resin components, fillers, sensitizers, adhesion aids, thermal polymerization inhibitors, azole compounds, and hindered phenol compounds.

[0099] <<Thermal Curing Agent>> Examples of the thermal curing agent include hexamethoxymethylmelamine, tetramethoxymethylglycoluril, tetramethoxymethylbenzoguanamine, 1,3,4,6-tetrakis(methoxymethyl)glycoluril, 1,3,4,6-tetrakis(butoxymethyl)glycoluril, 1,3,4,6-tetrakis(hydroxymethyl)glycoluril, 1,3-bis(hydroxymethyl)urea, 1,1,3,3-tetrakis(butoxymethyl)urea, and 1,1,3,3-tetrakis(methoxymethyl)urea. The content of the thermal curing agent in the photosensitive resin composition for forming an insulating film is not particularly limited.

[0100] <<Filler>> Examples of the filler include inorganic fillers, and specific examples include sols of silica, aluminum nitride, boron nitride, zirconia, alumina, etc. The content of the filler in the photosensitive resin composition for forming an insulating film is not particularly limited.

[0101] <<Other Resin Components>> In an embodiment, the photosensitive resin composition for forming an insulating film may further contain a resin component other than the specific polyimide. Examples of resin components that can be contained in the photosensitive resin composition for forming an insulating film include polyimides other than the specific polyimide, polyoxazoles, polyoxazole precursors, phenolic resins, polyamides, epoxy resins, siloxane resins, and acrylic resins. The content of these resin components is not particularly limited, but is preferably in the range of 0.01 parts by mass to 20 parts by mass per 100 parts by mass of the specific polyimide.

[0102] <<Sensitizer>> In the embodiment, a sensitizer can be optionally blended into the photosensitive resin composition for forming an insulating film to improve photosensitivity. Examples of the sensitizer include Michler's ketone, 4,4'-bis(diethylamino)benzophenone, 2,5-bis(4'-diethylaminobenzal)cyclopentane, 2,6-bis(4'-diethylaminobenzal)cyclohexanone, 2,6-bis(4'-diethylaminobenzal)-4-methylcyclohexanone, 4,4'-bis(dimethylamino)chalcone, 4,4'-bis(diethylamino)chalcone, and p-dimethylaminocinnamylideneindano. p-dimethylaminobenzylidene indanone, 2-(p-dimethylaminophenylbiphenylene)benzothiazole, 2-(p-dimethylaminophenylvinylene)benzothiazole, 2-(p-dimethylaminophenylvinylene)isonaphthothiazole, 1,3-bis(4'-dimethylaminobenzal)acetone, 1,3-bis(4'-diethylaminobenzal)acetone, 3,3'-carbonyl-bis(7-diethylaminocoumarin), 3-acetyl

[0039] Examples of the methylaminobenzoate include methylaminobenzoate, ... These may be used alone or in combination.

[0103] The content of the sensitizer is not particularly limited, but is preferably 0.1 to 25 parts by mass relative to 100 parts by mass of the specific polyimide.

[0104] <<Adhesion Aid>> In an embodiment, in order to improve the adhesion between a film formed using the insulating film-forming photosensitive resin composition and a substrate, an adhesion aid can be optionally blended into the insulating film-forming photosensitive resin composition. Examples of the adhesion aid include γ-aminopropyldimethoxysilane, N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-mercaptopropylmethyldimethoxysilane, 3-(meth)acryloxypropyldimethoxymethylsilane, 3-(meth)acryloxypropyltrimethoxysilane, dimethoxymethyl-3-piperidinopropylsilane, diethoxy-3-glycidoxypropylmethylsilane, N-(3-diethoxymethylsilylpropyl)succinimide, N-[3-(triethoxysilyl)propyl]furan, and the like. Examples of the adhesive agent include silane coupling agents such as thalamic acid, benzophenone-3,3'-bis(N-[3-triethoxysilyl]propylamido)-4,4'-dicarboxylic acid, benzene-1,4-bis(N-[3-triethoxysilyl]propylamido)-2,5-dicarboxylic acid, 3-(triethoxysilyl)propyl succinic anhydride and N-phenylaminopropyltrimethoxysilane, and aluminum-based adhesion promoters such as aluminum tris(ethylacetoacetate), aluminum tris(acetylacetonate) and ethylacetoacetate aluminum diisopropylate.

[0105] Among these adhesion aids, it is more preferable to use a silane coupling agent in terms of adhesive strength.

[0106] The content of the adhesion promoter is not particularly limited, but is preferably in the range of 0.5 to 25 parts by mass per 100 parts by mass of the specific polyimide.

[0107] <<Thermal Polymerization Inhibitor>> In an embodiment, a thermal polymerization inhibitor can be optionally blended to improve the stability of the viscosity and photosensitivity of the photosensitive resin composition for forming an insulating film, particularly during storage in the form of a solution containing a solvent. Examples of the thermal polymerization inhibitor include hydroquinone, 4-methoxyphenol, N-nitrosodiphenylamine, p-tert-butylcatechol, phenothiazine, N-phenylnaphthylamine, ethylenediaminetetraacetic acid, 1,2-cyclohexanediaminetetraacetic acid, glycol ether diaminetetraacetic acid, 2,6-di-tert-butyl-p-cresol, 5-nitroso-8-hydroxyquinoline, 1-nitroso-2-naphthol, 2-nitroso-1-naphthol, 2-nitroso-5-(N-ethyl-N-sulfopropylamino)phenol, N-nitroso-N-phenylhydroxylamine ammonium salt, and N-nitroso-N(1-naphthyl)hydroxylamine ammonium salt.

[0108] The content of the thermal polymerization inhibitor is not particularly limited, but is preferably in the range of 0.005 to 12 parts by mass per 100 parts by mass of the specific polyimide.

[0109] <<Azole Compounds>> For example, when a substrate made of copper or a copper alloy is used, an azole compound can be optionally blended into the photosensitive resin composition for forming an insulating film to suppress discoloration of the substrate. Examples of the azole compound include 1H-triazole, 5-methyl-1H-triazole, 5-ethyl-1H-triazole, 4,5-dimethyl-1H-triazole, 5-phenyl-1H-triazole, 4-t-butyl-5-phenyl-1H-triazole, 5-hydroxyphenyl-1H-triazole, phenyltriazole, p-ethoxyphenyltriazole, 5-phenyl-1-(2-dimethylaminoethyl)triazole, 5-benzyl-1H-triazole, hydroxyphenyltriazole, 1,5-dimethyltriazole, 4,5-diethyl-1H-triazole, 1H-benzotriazole, 2-(5-methyl-2-hydroxyphenyl)benzotriazole, 2-[2-hydroxy-3,5-bis(α,α-dimethylbenzyl)phenyl]-benzotriazole, and the like. benzotriazole, 2-(3,5-di-t-butyl-2-hydroxyphenyl)benzotriazole, 2-(3-t-butyl-5-methyl-2-hydroxyphenyl)benzotriazole, 2-(3,5-di-t-amyl-2-hydroxyphenyl)benzotriazole, 2-(2'-hydroxy-5'-t-octylphenyl)benzotriazole, hydroxyphenylbenzotriazole, tolyltriazole, 5-methyl-1H-benzotriazole, 4-methyl-1H-benzotriazole, 4-carboxy-1H-benzotriazole, 5-carboxy-1H-benzotriazole, 1H-tetrazole, 5-methyl-1H-tetrazole, 5-phenyl-1H-tetrazole, 5-amino-1H-tetrazole, 1-methyl-1H-tetrazole, and the like. Particularly preferred are 4-carboxy-1H-benzotriazole and 5-carboxy-1H-benzotriazole. These azole compounds may be used alone or in a mixture of two or more.

[0110] The content of the azole compound is not particularly limited, but is preferably 0.1 to 20 parts by mass relative to 100 parts by mass of the specific polyimide, and more preferably 0.5 to 5 parts by mass from the viewpoint of photosensitivity characteristics. When the content of the azole compound relative to 100 parts by mass of the specific polyimide is 0.1 part by mass or more, discoloration of the copper or copper alloy surface is suppressed when the insulating film-forming photosensitive resin composition is formed on copper or a copper alloy, while when the content is 20 parts by mass or less, excellent photosensitivity is achieved, which is preferable.

[0111] <<Hindered Phenol Compound>> In the embodiment, a hindered phenol compound can be optionally blended into the photosensitive resin composition for forming an insulating film in order to suppress discoloration on copper. Examples of the hindered phenol compound include 2,6-di-t-butyl-4-methylphenol, 2,5-di-t-butyl-hydroquinone, octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, isooctyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, 4,4'-methylenebis(2,6-di-t-butylphenol), 4,4'-thio-bis(3-methyl-6-t-butylphenol), 4,4'-butylidene-bis(3-methyl-6-t-butylphenol), and 4,4'-butylidene-bis(3-methyl-6-t-butylphenol). N,N'-hexamethylenebis(3,5-di-t-butyl-4-hydroxy-hydrocinnamamide), triethylene glycol-bis[3-(3-t-butyl-5-methyl-4-hydroxyphenyl)propionate], 1,6-hexanediol-bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], 2,2-thio-diethylenebis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], N,N'-hexamethylenebis(3,5-di-t-butyl-4-hydroxy-hydrocinnamamide), 2,2'-methylene -bis(4-methyl-6-t-butylphenol), 2,2'-methylene-bis(4-ethyl-6-t-butylphenol), pentaerythrityl-tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], tris-(3,5-di-t-butyl-4-hydroxybenzyl)-isocyanurate, 1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene, 1,3,5-tris(3-hydroxy-2,6-dimethyl-4- isopropylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-t-butyl-3-hydroxy-2,6-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-s-butyl-3-hydroxy-2,6-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris[4-(1-ethylpropyl)-3-hydroxy-2,1,3,5-tris[4-triethylmethyl-3-hydroxy-2,6-dimethylbenzyl]-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(3-hydroxy-2,6-dimethyl-4-phenylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4- t-butyl-3-hydroxy-2,5,6-trimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-t-butyl-5-ethyl-3-hydroxy-2,6-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-t-butyl-6-ethyl-3-hydroxy-2-methylbenzyl)-1,3,5-triazine-2,4,6-(1H ,3H,5H)-trione, 1,3,5-tris(4-t-butyl-6-ethyl-3-hydroxy-2,5-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-t-butyl-5,6-diethyl-3-hydroxy-2-methylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-t-butyl-3-hydroxy-2-methylbenzyl) Examples of the hydroxybenzoates include, but are not limited to, 1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-t-butyl-3-hydroxy-2,5-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, and 1,3,5-tris(4-t-butyl-5-ethyl-3-hydroxy-2-methylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione. Among these, 1,3,5-tris(4-t-butyl-3-hydroxy-2,6-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione is particularly preferred.

[0112] The content of the hindered phenol compound is not particularly limited, but is preferably 0.1 to 20 parts by mass relative to 100 parts by mass of the specific polyimide, and more preferably 0.5 to 10 parts by mass from the viewpoint of photosensitivity characteristics. When the content of the hindered phenol compound relative to 100 parts by mass of the specific polyimide is 0.1 part by mass or more, for example, when the insulating film-forming photosensitive resin composition is formed on copper or a copper alloy, discoloration and corrosion of the copper or copper alloy are prevented, while when the content is 20 parts by mass or less, excellent photosensitivity is achieved, which is preferable.

[0113] The photosensitive resin composition for forming an insulating film can be suitably used as a negative photosensitive resin composition for forming an insulating film for producing a cured relief pattern as described below.

[0114] (Insulating Film) The insulating film of the present invention is a baked product of a coating film of the insulating film-forming photosensitive resin composition of the present invention. Examples of the coating method include methods conventionally used for coating insulating film-forming photosensitive resin compositions, such as coating with a spin coater, bar coater, blade coater, curtain coater, or screen printer, and spray coating with a spray coater. If necessary, prebaking can be performed to dry the coating film of the insulating film-forming photosensitive resin composition. Examples of prebaking methods include air drying, heat drying using an oven or hot plate, and vacuum drying. Specifically, when air drying or heat drying is performed, drying can be performed at 20°C to 140°C (preferably 20°C to 130°C) for 1 minute to 1 hour. This allows a photosensitive resin layer to be formed on the substrate. Various methods can be selected for curing to obtain the baked product, such as using a hot plate, an oven, or a temperature-programmable heating oven. Curing can be carried out, for example, at 130°C to 300°C, preferably 140°C to 250°C, and more preferably 180°C to 200°C for 30 minutes to 5 hours. Air may be used as the atmospheric gas during heat curing, or an inert gas such as nitrogen or argon may also be used. The thickness of the insulating film is not particularly limited, but is preferably 1 μm to 100 μm, and more preferably 2 μm to 50 μm.

[0115] (Photosensitive Resist Film) The photosensitive resin composition for forming an insulating film of the present invention can be used for a photosensitive resist film (so-called dry film resist). The photosensitive resist film has a base film, a photosensitive resin layer (photosensitive resin film) formed from the photosensitive resin composition for forming an insulating film of the present invention, and a cover film. Usually, the photosensitive resin layer and the cover film are laminated in this order on the base film.

[0116] The photosensitive resist film can be produced, for example, by applying a photosensitive resin composition for forming an insulating film to a substrate film, drying the composition to form a photosensitive resin layer, and then laminating a cover film on the photosensitive resin layer. The application method can be a conventional method used to apply a photosensitive resin composition for forming an insulating film, such as using a spin coater, bar coater, blade coater, curtain coater, or screen printer, or spray coating using a spray coater. Drying can be performed, for example, at 20°C to 140°C (preferably 20°C to 130°C) for 1 minute to 1 hour. The thickness of the resulting photosensitive resin layer is not particularly limited, but is preferably 1 μm to 100 μm, and more preferably 2 μm to 50 μm.

[0117] Known materials can be used for the base film, such as a thermoplastic resin film. Examples of such thermoplastic resins include polyesters such as polyethylene terephthalate. The thickness of the base film is preferably 2 μm to 150 μm. Known materials can be used for the cover film, such as a polyethylene film or a polypropylene film. The cover film is preferably a film that has a lower adhesive strength with the photosensitive resin layer than the base film. The thickness of the cover film is preferably 2 μm to 150 μm, more preferably 2 μm to 100 μm, and particularly preferably 5 μm to 50 μm. The base film and the cover film may be made of the same film material, or different films may be used.

[0118] (Method for manufacturing a substrate having a cured relief pattern) The method for manufacturing a substrate having a cured relief pattern of the present invention includes the steps of: (1) applying the photosensitive resin composition for forming an insulating film of the present invention onto a substrate to form a photosensitive resin layer (photosensitive resin film) on the substrate; (2) exposing the photosensitive resin layer to light; (3) developing the exposed photosensitive resin layer to form a relief pattern; and (4) heat-treating the relief pattern to form a cured relief pattern.

[0119] Each step will be described below. (1) Step of applying the insulating film-forming photosensitive resin composition of the present invention onto a substrate to form a photosensitive resin layer on the substrate In this step, the insulating film-forming photosensitive resin composition of the present invention is applied onto a substrate, and then dried, if necessary, to form a photosensitive resin layer. As the application method, any method conventionally used for applying insulating film-forming photosensitive resin compositions can be used, such as application using a spin coater, bar coater, blade coater, curtain coater, screen printing machine, or the like, or spray application using a spray coater.

[0120] If necessary, pre-baking can be performed to dry the coating film made of the photosensitive resin composition for forming an insulating film. Examples of pre-baking methods include air drying, heat drying using an oven or a hot plate, and vacuum drying. Specifically, when air drying or heat drying is performed, drying can be performed at 20°C to 140°C (preferably 20°C to 130°C) for 1 minute to 1 hour. In this manner, a photosensitive resin layer can be formed on the substrate.

[0121] (2) Step of Exposing Photosensitive Resin Layer In this step, the photosensitive resin layer formed in step (1) above is exposed to an ultraviolet light source or the like using an exposure device such as a contact aligner, mirror projection, or stepper, either directly or through a patterned photomask or reticle. Examples of light sources used for exposure include g-line, h-line, i-line, ghi-line broadband, and KrF excimer laser. The exposure dose is 25 mJ / cm. ２ ~2000mJ / cm ２ is desirable.

[0122] Thereafter, for the purpose of improving photosensitivity, etc., post-exposure baking (PEB) and / or pre-development baking may be performed at any combination of temperature and time, as necessary. The baking conditions range for the temperature is preferably 50°C to 140°C, more preferably 50°C to 130°C, and the time is preferably 10 seconds to 600 seconds, but are not limited to these ranges as long as the various properties of the photosensitive resin composition for forming an insulating film are not impaired.

[0123] (3) Step of Developing the Exposed Photosensitive Resin Layer to Form a Relief Pattern In this step, the unexposed portions of the exposed photosensitive resin layer are developed and removed. The development method for developing the exposed (irradiated) photosensitive resin layer can be any of the conventional photoresist development methods, such as the rotary spray method, the paddle method, and the immersion method accompanied by ultrasonic treatment. After development, rinsing may be performed to remove the developer. Furthermore, post-development baking may be performed at any temperature and time combination, as needed, for purposes such as adjusting the shape of the relief pattern. The developer used for development is preferably an organic solvent. Examples of preferred organic solvents include N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N-cyclohexyl-2-pyrrolidone, N,N-dimethylacetamide, cyclopentanone, cyclohexanone, γ-butyrolactone, and α-acetyl-γ-butyrolactone. Two or more of each solvent, for example, a combination of several solvents, may also be used. The rinse solution used for rinsing is preferably an organic solvent that is miscible with the developer and has low solubility in the photosensitive resin composition for forming an insulating film. Examples of preferred rinse solutions include methanol, ethanol, isopropyl alcohol, ethyl lactate, propylene glycol methyl ether acetate, toluene, and xylene. Two or more types of each solvent, for example, a combination of several types, can also be used.

[0124] (4) Step of Heating the Relief Pattern to Form a Hardened Relief Pattern In this step, the relief pattern obtained by the development described above is heated to convert it into a hardened relief pattern. Various methods can be selected for heat curing, such as using a hot plate, an oven, or a temperature-programmable heating oven. Heating can be carried out, for example, at 130°C to 300°C, preferably 140°C to 250°C, and more preferably 180°C to 200°C, for 30 minutes to 5 hours. The atmospheric gas used during heat curing may be air, or an inert gas such as nitrogen or argon.

[0125] The thickness of the cured relief pattern is not particularly limited, but is preferably 1 μm to 100 μm, and more preferably 2 μm to 50 μm.

[0126] (Semiconductor Device) In an embodiment, a semiconductor device is also provided, comprising a semiconductor element and a cured film disposed above or below the semiconductor element. The cured film is a cured relief pattern formed from the photosensitive resin composition for forming an insulating film of the present invention. The cured relief pattern can be obtained, for example, by steps (1) to (4) in the method for manufacturing a substrate having a cured relief pattern described above. The present invention is also applicable to a method for manufacturing a semiconductor device that uses a semiconductor element as a substrate and includes the method for manufacturing a substrate having a cured relief pattern described above as part of its processes. The semiconductor device of the present invention can be manufactured by forming the cured relief pattern as a surface protective film, an interlayer insulating film, an insulating film for rewiring, a protective film for a flip-chip device, or a protective film for a semiconductor device having a bump structure, and combining this with a known method for manufacturing a semiconductor device.

[0127] (Display Device) In an embodiment, a display device is provided that includes a display element and a cured film provided on the display element, the cured film having the above-described cured relief pattern. Here, the cured relief pattern may be laminated in direct contact with the display element, or may be laminated with another layer sandwiched therebetween. Examples of the cured film include surface protection films, insulating films, and planarizing films for TFT (Thin Film Transistor) liquid crystal display elements and color filter elements, protrusions for MVA (Multi-Domain Vertical Alignment) liquid crystal display devices, and partition walls for cathodes of organic EL (Electro-Luminescence) elements.

[0128] The photosensitive resin composition for forming an insulating film of the present invention is useful not only for application to the semiconductor device described above, but also for applications such as an interlayer insulating film in a multilayer circuit, a cover coat for a flexible copper-clad board, a solder resist film, and a liquid crystal alignment film.

[0129] The present invention will now be described in detail with reference to examples, but the present invention is not limited to these examples.

[0130] The compounds shown in the following synthesis examples are as follows: 6FDA: 4,4'-[perfluoro(propane-2,2-diyl)]diphthalic anhydride (manufactured by Daikin Industries, Ltd.)

[0131] TMPBP-TME: 2,2',3,3',5,5'-hexamethyl-[1,1'-biphenyl]-4,4'-diylbis(1,3-dioxo-1,3-dihydroisobenzofuran-5-carboxylate) (manufactured by Honshu Chemical Industry Co., Ltd.)

[0132] H-BPDA: 1,1'-bicyclohexane-3,3',4,4'-tetracarboxylic acid-3,3',4,4'-dianhydride

[0133] SD1100P: 4,4'-(4,4'-isopropylidenediphenoxy)diphthalic anhydride (SHPP Japan LLC)

[0134] BEM-S: 2-(methacryloyloxy)ethyl 3,5-diaminobenzoate

[0135] DAB-C18: 4-octadecyloxy-1,3-phenylenediamine

[0136] BAPP: 2,2-bis[4-(4-aminophenoxy)phenyl]propane (manufactured by Wakayama Seika Kogyo Co., Ltd.)

[0137] The weight-average molecular weights (Mw) shown in the synthesis examples below in this specification are the results of measurements by gel permeation chromatography (hereinafter abbreviated as GPC in this specification). For the measurements, a GPC device (HLC-8320GPC (manufactured by Tosoh Corporation)) was used, and the measurement conditions were as follows:

[0138] Column: Shodex (registered trademark) KD-805 / Shodex (registered trademark) KD-803 (Resonac Corporation) Column temperature: 50°C Flow rate: 1 mL / min Eluent: N,N-dimethylformamide (DMF), lithium bromide monohydrate (30 mM) / phosphoric acid (30 mM) / tetrahydrofuran (1%) Standard sample: polyethylene oxide

[0139] The chemical imidization ratio shown in the synthesis examples below in this specification was calculated by the following method. 100 mg of polyimide powder was placed in an NMR sample tube (NMR Sampling Tube Standard, φ5 (Kusano Scientific Co., Ltd.)), and deuterated tetrahydrofuran (THF-d8, 0.05% TMS (tetramethylsilane) mixture) (0.53 ml) was added and completely dissolved using ultrasound. This solution was subjected to 500 MHz proton NMR measurement using an NMR measurement device (JNM-ECA500) (JEOL Datum Co., Ltd.). The chemical imidization ratio was calculated by the following formula, using a proton derived from a structure that remains unchanged before and after imidization as the reference proton, and the integrated value of the peak of this proton and the integrated value of the proton peak derived from the NH group of the amic acid that appears around 9.5 ppm to 11.0 ppm. Chemical imidization rate (%)=(1−α×x / y)×100 In the above formula, x is the integrated value of the proton peak derived from the NH group of the amic acid, y is the integrated value of the peak of the reference proton, and α is the ratio of the number of reference protons to one NH group proton of the amic acid in the case of polyamic acid (imidization rate 0%).

[0140] Synthesis Example 1 Synthesis of Polyamic Acid (P-1) 15.99 g (60.50 mmol) of BEM-S, 9.93 g (24.20 mmol) of BAPP, 13.67 g (36.30 mmol) of DAB-C18, 0.15 g of 4-methoxyphenol, and 228.48 g of N-ethyl-2-pyrrolidone were placed in a four-neck flask and stirred at room temperature under air to dissolve the mixture. Then, 43.79 g (70.79 mmol) of TMPBP-TME, 11.12 g (36.30 mmol) of H-BPDA, 6.30 g (12.10 mmol) of SD1100P, and 342.72 g of N-ethyl-2-pyrrolidone were added to the system, and the mixture was stirred at room temperature for 1 hour and then at 50° C. for 22 hours. The resulting polyamic acid solution (P-1) had a weight average molecular weight (Mw) of 24,855 as determined by GPC.

[0141] Synthesis Example 2: Synthesis of Alkali-Insoluble Polyimide (P-2) 355.50 g of N-ethyl-2-pyrrolidone, 37.01 g of acetic anhydride, and 6.11 g of triethylamine were added to 671.0 g of the polyamic acid solution (P-1) obtained in Synthesis Example 1. The mixture was stirred in air at room temperature for 30 minutes, followed by stirring at 60°C for 3 hours. 111.83 g of N-ethyl-2-pyrrolidone was added to this solution. The resulting solution was slowly added to 2,624.03 g of stirring methanol, followed by stirring for 60 minutes, and the resulting precipitate was filtered off. The precipitate was washed with 1,050.61 g of methanol and then filtered off. The precipitate was washed again with 1,050.61 g of methanol and then filtered off. The mixture was dried under reduced pressure at 50°C to obtain a powder of alkali-insoluble polyimide (P-2). The chemical imidization rate was 98.3%.

[0142] Synthesis Example 3 Synthesis of Polyamic Acid (P-3) 30.39 g (115.00 mmol) of BEM-S, 18.88 g (46.00 mmol) of BAPP, 25.99 g (69.00 mmol) of DAB-C18, and 456.15 g of N-ethyl-2-pyrrolidone were dissolved in a four-neck flask by stirring at room temperature under air, and then 95.32 g (154.10 mmol) of TMPBP-TME, 30.65 g (69.00 mmol) of 6FDA, and 684.41 g of N-ethyl-2-pyrrolidone were added to the system, followed by stirring at room temperature for 1 hour and then at 50° C. for 22 hours. The resulting polyamic acid solution (P-3) had a weight average molecular weight (Mw) of 36,624 as determined by GPC.

[0143] Synthesis Example 4: Synthesis of Alkali-Insoluble Polyimide (P-4) 670.00 g of N-ethyl-2-pyrrolidone, 70.37 g of acetic anhydride, and 11.62 g of triethylamine were added to 1,340.00 g of the polyamic acid solution (P-3) obtained in Synthesis Example 3. The mixture was stirred in air at room temperature for 30 minutes, followed by stirring at 60°C for 3 hours. 861.43 g of N-ethyl-2-pyrrolidone was added to this solution. The resulting solution was slowly added to 7,383.54 g of stirring methanol, followed by stirring for 60 minutes, and the resulting precipitate was filtered off. The precipitate was washed with 2,953.42 g of methanol and then filtered off. The precipitate was washed again with 2,953.42 g of methanol and then filtered off. The mixture was dried under reduced pressure at 50°C to obtain a powder of alkali-insoluble polyimide (P-4). The chemical imidization rate was 96.9%.

[0144] The compounds shown in the examples and comparative examples are as follows: NK ester A-DOD-N: 1,10-decanediol diacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd.) BMI-689: maleimide compound represented by the following formula (manufactured by Designer Molecules Inc.)

[0145] NCI-930 (O-acyloxime compound, manufactured by ADEKA Corporation) Omnirad (registered trademark) 819: bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide (manufactured by IGM Resins Co., Ltd.) KBM-5103: 3-acryloxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.) IRGACURE (registered trademark) OXE01: 1,2-octanedione, 1-[4-(phenylthio)phenyl]-, 2-(O-benzoyloxime) (manufactured by BASF Japan Ltd.) CBT-SG: mixture of 4-carboxybenzotriazole and 5-carboxybenzotriazole (manufactured by Johoku Chemical Industry Co., Ltd.) Percumyl (registered trademark) P: diisopropylbenzene hydroperoxide (manufactured by NOF Corporation) Percumyl (registered trademark) D: dicumyl peroxide (manufactured by NOF Corporation) Perbutyl (registered trademark) P: α,α-di(tert-butylperoxy)diisopropylbenzene (manufactured by NOF Corporation) Perbutyl (registered trademark) P 20% by mass diluted product: 20% by mass solution of Perbutyl (registered trademark) P in cyclopentanone Perbutyl (registered trademark) P 15% by mass diluted product: 15% by mass solution of Perbutyl (registered trademark) P in cyclopentanone Perbutyl (registered trademark) O: tert-butylperoxy-2-ethylhexanoate (manufactured by NOF Corporation), 1-minute half-life temperature: 134.0°C

[0146] Example 1 21.20 g of the alkali-insoluble polyimide (P-2) powder obtained in Synthesis Example 2, 23.69 g of N-ethyl-2-pyrrolidone, 31.59 g of γ-butyrolactone, 23.69 g of cyclohexanone, 3.18 g of NK-ester A-DOD-N, 3.18 g of BMI-689, 0.21 g of NCI-930, 1.27 g of Omnirad (registered trademark) 819, 0.43 g of KBM-5103, 0.32 g of CBT-SG, and 1.70 g of Percumyl (registered trademark) P were mixed and dissolved, and then filtered using a polypropylene filter having a pore size of 5 μm, to prepare a negative photosensitive resin composition (solution).

[0147] Example 2 4.19 g of the alkali-insoluble polyimide (P-4) powder obtained in Synthesis Example 4, 5.86 g of N-ethyl-2-pyrrolidone, 7.81 g of γ-butyrolactone, 5.86 g of cyclohexanone, 0.63 g of NK ester A-DOD-N, 0.63 g of BMI-689, 0.042 g of NCI-930, 0.25 g of Omnirad (registered trademark) 819, 0.083 g of KBM-5103, 0.063 g of CBT-SG, and 0.34 g of Percumyl (registered trademark) P were mixed and dissolved, and the mixture was filtered using a polypropylene filter having a pore size of 5 μm, to prepare a negative photosensitive resin composition (solution).

[0148] Example 3 7.00 g of the alkali-insoluble polyimide (P-4) powder obtained in Synthesis Example 4, 10.76 g of N-ethyl-2-pyrrolidone, 14.34 g of γ-butyrolactone, 10.75 g of cyclohexanone, 1.05 g of NK ester A-DOD-N, 1.05 g of BMI-689, 0.070 g of NCI-930, 0.42 g of Omnirad (registered trademark) 819, 0.14 g of KBM-5103, 0.11 g of CBT-SG, and 0.28 g of Percumyl (registered trademark) D were mixed and dissolved, and the mixture was filtered using a polypropylene filter having a pore size of 5 μm, to prepare a negative photosensitive resin composition (solution).

[0149] Example 4 7.40 g of the alkali-insoluble polyimide (P-2) powder obtained in Synthesis Example 2, 7.35 g of N-ethyl-2-pyrrolidone, 9.80 g of γ-butyrolactone, 7.35 g of cyclohexanone, 1.11 g of NK ester A-DOD-N, 1.11 g of BMI-689, 0.074 g of NCI-930, 0.44 g of Omnirad (registered trademark) 819, 0.15 g of KBM-5103, 0.11 g of CBT-SG, and 0.30 g of Percumyl (registered trademark) P were mixed and dissolved, and then filtered using a polypropylene filter having a pore size of 5 μm, to prepare a negative photosensitive resin composition (solution).

[0150] Example 5 7.40 g of the alkali-insoluble polyimide (P-2) powder obtained in Synthesis Example 2, 7.37 g of N-ethyl-2-pyrrolidone, 9.81 g of γ-butyrolactone, 7.35 g of cyclohexanone, 1.11 g of NK ester A-DOD-N, 1.11 g of BMI-689, 0.074 g of NCI-930, 0.44 g of Omnirad (registered trademark) 819, 0.15 g of KBM-5103, 0.11 g of CBT-SG, and 0.74 g of Percumyl (registered trademark) P were mixed and dissolved, and then filtered using a polypropylene filter having a pore size of 5 μm, to prepare a negative photosensitive resin composition (solution).

[0151] Example 6 9.30 g of the alkali-insoluble polyimide (P-2) powder obtained in Synthesis Example 2, 12.48 g of N,N-dimethylpropionamide, 12.48 g of cyclopentanone, 1.40 g of NK ester A-DOD-N, 1.40 g of BMI-689, 0.093 g of NCI-930, 0.56 g of Omnirad (registered trademark) 819, 0.19 g of KBM-5103, 0.14 g of CBT-SG, and 0.37 g of Perbutyl (registered trademark) P were mixed and dissolved, and then filtered using a polypropylene filter having a pore size of 5 μm, to prepare a negative photosensitive resin composition (solution).

[0152] Example 7 9.30 g of the alkali-insoluble polyimide (P-2) powder obtained in Synthesis Example 2, 15.79 g of N,N-dimethylpropionamide, 15.79 g of cyclopentanone, 1.40 g of NK ester A-DOD-N, 1.40 g of BMI-689, 0.19 g of IRGACURE (registered trademark) OXE01, 0.56 g of Omnirad (registered trademark) 819, 0.19 g of KBM-5103, 0.14 g of CBT-SG, and 0.37 g of Perbutyl (registered trademark) P were mixed and dissolved, and then filtered using a polypropylene filter having a pore size of 5 μm, to prepare a negative photosensitive resin composition (solution).

[0153] Example 8 9.30 g of the alkali-insoluble polyimide (P-2) powder obtained in Synthesis Example 2, 15.89 g of N,N-dimethylpropionamide, 15.89 g of cyclopentanone, 1.40 g of NK ester A-DOD-N, 1.40 g of BMI-689, 0.28 g of IRGACURE (registered trademark) OXE01, 0.56 g of Omnirad (registered trademark) 819, 0.19 g of KBM-5103, 0.14 g of CBT-SG, and 0.37 g of Perbutyl (registered trademark) P were mixed and dissolved, and then filtered using a polypropylene filter having a pore size of 5 μm, to prepare a negative photosensitive resin composition (solution).

[0154] Example 9 9.30 g of the alkali-insoluble polyimide (P-2) powder obtained in Synthesis Example 2, 16.00 g of N,N-dimethylpropionamide, 16.00 g of cyclopentanone, 1.40 g of NK ester A-DOD-N, 1.40 g of BMI-689, 0.37 g of IRGACURE (registered trademark) OXE01, 0.56 g of Omnirad (registered trademark) 819, 0.19 g of KBM-5103, 0.14 g of CBT-SG, and 0.37 g of Perbutyl (registered trademark) P were mixed and dissolved, and then filtered using a polypropylene filter having a pore size of 5 μm, to prepare a negative photosensitive resin composition (solution).

[0155] Example 10 9.30 g of the alkali-insoluble polyimide (P-2) powder obtained in Synthesis Example 2, 15.15 g of N,N-dimethylpropionamide, 15.15 g of cyclopentanone, 1.40 g of NK ester A-DOD-N, 1.40 g of BMI-689, 0.19 g of IRGACURE (registered trademark) OXE01, 0.19 g of KBM-5103, 0.14 g of CBT-SG, and 0.37 g of Perbutyl (registered trademark) P were mixed and dissolved, and then filtered using a polypropylene filter having a pore size of 5 μm, to prepare a negative photosensitive resin composition (solution).

[0156] Example 11 9.30 g of the alkali-insoluble polyimide (P-2) powder obtained in Synthesis Example 2, 15.24 g of N,N-dimethylpropionamide, 15.24 g of cyclopentanone, 1.40 g of NK ester A-DOD-N, 1.40 g of BMI-689, 0.28 g of IRGACURE (registered trademark) OXE01, 0.19 g of KBM-5103, 0.14 g of CBT-SG, and 0.37 g of Perbutyl (registered trademark) P were mixed and dissolved, and then filtered using a polypropylene filter having a pore size of 5 μm, to prepare a negative photosensitive resin composition (solution).

[0157] Example 12 9.30 g of the alkali-insoluble polyimide (P-2) powder obtained in Synthesis Example 2, 15.35 g of N,N-dimethylpropionamide, 15.35 g of cyclopentanone, 1.40 g of NK ester A-DOD-N, 1.40 g of BMI-689, 0.37 g of IRGACURE (registered trademark) OXE01, 0.19 g of KBM-5103, 0.14 g of CBT-SG, and 0.37 g of Perbutyl (registered trademark) P were mixed and dissolved, and then filtered using a polypropylene filter having a pore size of 5 μm, to prepare a negative photosensitive resin composition (solution).

[0158] Example 13 9.30 g of the alkali-insoluble polyimide (P-2) powder obtained in Synthesis Example 2, 15.35 g of N,N-dimethylpropionamide, 15.35 g of cyclopentanone, 1.40 g of NK ester A-DOD-N, 1.40 g of BMI-689, 0.37 g of IRGACURE (registered trademark) OXE01, 0.19 g of KBM-5103, 0.14 g of CBT-SG, and 0.74 g of Perbutyl (registered trademark) P were mixed and dissolved, and then filtered using a polypropylene filter having a pore size of 5 μm, to prepare a negative photosensitive resin composition (solution).

[0159] Example 14 9.30 g of the alkali-insoluble polyimide (P-2) powder obtained in Synthesis Example 2, 15.35 g of N,N-dimethylpropionamide, 12.37 g of cyclopentanone, 1.40 g of NK ester A-DOD-N, 1.40 g of BMI-689, 0.37 g of IRGACURE (registered trademark) OXE01, 0.19 g of KBM-5103, 0.14 g of CBT-SG, and 3.72 g of a 20% by mass diluted Perbutyl (registered trademark) P were mixed and dissolved, and then filtered using a polypropylene filter having a pore size of 5 μm, to prepare a negative photosensitive resin composition (solution).

[0160] Example 15 9.30 g of the alkali-insoluble polyimide (P-2) powder obtained in Synthesis Example 2, 15.35 g of N,N-dimethylpropionamide, 11.14 g of cyclopentanone, 1.40 g of NK ester A-DOD-N, 1.40 g of BMI-689, 0.37 g of IRGACURE (registered trademark) OXE01, 0.19 g of KBM-5103, 0.14 g of CBT-SG, and 4.96 g of a 15% by mass diluted Perbutyl (registered trademark) P were mixed and dissolved, and the mixture was filtered using a polypropylene filter having a pore size of 5 μm, to prepare a negative photosensitive resin composition (solution).

[0161] Comparative Example 1 21.70 g of the alkali-insoluble polyimide (P-2) powder obtained in Synthesis Example 2, 23.70 g of N-ethyl-2-pyrrolidone, 31.59 g of γ-butyrolactone, 23.70 g of cyclohexanone, 3.19 g of NK ester A-DOD-N, 3.18 g of BMI-689, 0.21 g of NCI-930, 1.27 g of Omnirad (registered trademark) 819, 0.43 g of KBM-5103, and 0.32 g of CBT-SG were mixed and dissolved, and the mixture was filtered using a polypropylene filter having a pore size of 5 μm to prepare a solution of a negative photosensitive resin composition.

[0162] Comparative Example 2 282.66 g of the alkali-insoluble polyimide (P-4) powder obtained in Synthesis Example 4, 422.32 g of N-ethyl-2-pyrrolidone, 563.09 g of γ-butyrolactone, 422.32 g of cyclohexanone, 42.39 g of NK ester A-DOD-N, 42.41 g of BMI-689, 2.83 g of NCI-930, 16.96 g of Omnirad (registered trademark) 819, 5.65 g of KBM-5103, and 4.24 g of CBT-SG were mixed and dissolved, and the mixture was filtered using a polypropylene filter having a pore size of 5 μm, to prepare a negative photosensitive resin composition (solution).

[0163] Comparative Example 3 9.00 g of the alkali-insoluble polyimide (P-2) powder obtained in Synthesis Example 2, 9.33 g of N-ethyl-2-pyrrolidone, 12.43 g of γ-butyrolactone, 9.32 g of cyclohexanone, 1.35 g of NK ester A-DOD-N, 1.35 g of BMI-689, 0.090 g of NCI-930, 0.54 g of Omnirad (registered trademark) 819, 0.18 g of KBM-5103, 0.14 g of CBT-SG, and 0.36 g of Perbutyl (registered trademark) O were mixed and dissolved, and the mixture was filtered using a polypropylene filter having a pore size of 5 μm, to prepare a negative photosensitive resin composition (solution).

[0164] [Preparation of Film for Property Evaluation] The negative photosensitive resin compositions prepared in Examples 1 to 15 and Comparative Examples 1 and 2 were spin-coated onto a 4-inch silicon wafer (hereinafter referred to as "aluminum wafer") on which a 100 nm thick aluminum film had been sputtered, and the wafer was pre-baked on a hot plate at 115°C for 270 seconds to form a photosensitive resin film of approximately 25 µm on the aluminum wafer. Using an i-line aligner (PLA-501, manufactured by Canon Inc.), 500 mJ / cm was applied to the obtained photosensitive resin film on the aluminum wafer. ２After the entire surface was exposed to light with a UV ray, the film was cured in a nitrogen atmosphere at 230°C or 200°C for 2 hours using a high-temperature clean oven (CLH-21CD(V)-S, Koyo Thermo Systems Co., Ltd.). Furthermore, the photosensitive resin film was cut at 5 mm intervals using a dicing saw (DAD323, Disco Corporation), and the aluminum wafer was then immersed in 6N hydrochloric acid to dissolve the aluminum, thereby obtaining a 5 mm wide film for characteristic evaluation.

[0165] [Evaluation of Thermomechanical Properties] Using a thermomechanical analyzer (TMA), the coefficient of linear thermal expansion (hereinafter abbreviated as CTE in this specification) of the obtained film for property evaluation was measured in the range of 50°C to 100°C. The CTE measurement conditions were as follows: Thermomechanical analyzer (TMA): TMA4000SA (manufactured by Netsch Japan Co., Ltd.) Sample size: 20 mm x 5 mm Measurement temperature range: room temperature to 300°C Heating rate: 5°C / min Measurement atmosphere: nitrogen

[0166] [Evaluation of Dynamic Viscoelastic Properties] The glass transition temperature (hereinafter abbreviated as Tg in this specification) was determined from the peak temperature of the loss modulus curve at a frequency of 10 Hz and a heating rate of 10°C / min using the obtained film for property evaluation with a dynamic viscoelasticity measuring device (DMA). Dynamic viscoelasticity measuring device (DMA): Q800 (manufactured by TA Instruments Co., Ltd.) Sample size: 20 mm x 5 mm Measurement temperature range: room temperature to 300°C Heating rate: 10°C / min Measurement frequency: 10 Hz Measurement atmosphere: nitrogen

[0167] The CTE of the film measured by TMA and the Tg of the film determined by DMA are shown in Tables 1-1 and 1-2. Furthermore, the Tg decrease rate and the CTE increase rate were calculated using the following formula and are shown in Tables 1-1 and 1-2. Tg decrease rate (%) = [(Tg ２３０ -Tg ２００ ) / Tg ２３０ ]×100 ・Tg ２３０ : Tg when cured at 230°C for 2 hours Tg ２００ : Tg CTE increase rate (%) when cured at 200 ° C for 2 hours = [(CTE ２００ -CTE ２３０ ) / CTE２３０ ]×100 ・CTE ２３０ : CTE when cured at 230 ° C for 2 hours CTE ２００ : CTE when cured at 200°C for 2 hours. As a criterion for judging the deterioration of thermal properties due to a decrease in the curing temperature, a film obtained from a negative-type photosensitive resin composition of the same composition was rated as "good" if the decrease in Tg was ≦5% and the increase in CTE was ≦40%, and otherwise was rated as "poor."

[0168]

[0169]

[0170] The parts by mass of the thermal radical generator in Tables 1-1 to 4 represent parts by mass relative to 100 parts by mass of the alkali-insoluble polyimide.

[0171] From the results of Tables 1-1 and 1-2, it can be said that the films obtained from the resin compositions of Examples 1 to 15 are better able to suppress the deterioration of thermal properties associated with a decrease in cure temperature than the films obtained from the resin compositions of Comparative Examples 1 and 2.

[0172] [Evaluation of i-Line Transmittance] The negative photosensitive resin compositions prepared in Examples 1 to 3, 5, and 6 and Comparative Examples 1 and 2 were spin-coated onto a quartz substrate and pre-baked on a hot plate at 115°C for 270 seconds to form a photosensitive resin film having a thickness of 18 μm on the quartz substrate. The i-line transmittance of these photosensitive resin films at a wavelength of 365 nm was measured using a UV-2600 ultraviolet-visible spectrophotometer (manufactured by Shimadzu Corporation), and the results are shown in Tables 2-1 and 2-2. - UV-visible spectrophotometer: UV-2600 (manufactured by Shimadzu Corporation) - Measurement wavelength range: 200 nm to 800 nm

[0173]

[0174]

[0175] From the results in Table 2-1, it can be said that the photosensitive resin films obtained from the negative photosensitive resin compositions of Examples 1, 5, and 6 have higher i-line transmittance at a wavelength of 365 nm than the photosensitive resin film obtained from the negative photosensitive resin composition of Comparative Example 1. Similarly, from the results in Table 2-2, it can be said that the photosensitive resin films obtained from the negative photosensitive resin compositions of Examples 2 and 3 have higher i-line transmittance at a wavelength of 365 nm than the photosensitive resin film obtained from the negative photosensitive resin composition of Comparative Example 2.

[0176] [Evaluation of Electrical Properties] The negative photosensitive resin compositions prepared in Examples 1 to 15 and Comparative Examples 1 and 2 were spin-coated onto a 4-inch silicon wafer covered with 20 μm-thick aluminum foil, and pre-baked on a hot plate at 115° C. for 270 seconds to form a photosensitive resin film of approximately 22 μm on the aluminum foil. An i-line aligner (PLA-501, manufactured by Canon Inc.) was used to apply 500 mJ / cm to the obtained photosensitive resin film on the wafer. ２ After the entire surface was exposed to light with a UV ray, the foil was cured in a nitrogen atmosphere at 230°C for 2 hours using a high-temperature clean oven (CLH-21CD(V)-S, Koyo Thermo Systems Co., Ltd.). The cured aluminum foil was then immersed in 6N hydrochloric acid to dissolve the aluminum foil, thereby obtaining a photosensitive resin film. The obtained photosensitive resin film was dried, and the relative dielectric constant at 60 GHz was measured using a split cylinder resonator, and the results are shown in Tables 3-1 to 3-3. The relative dielectric constant was measured under the following conditions: Measurement method: Split cylinder resonance method Vector network analyzer: FieldFox N9926A (manufactured by Keysight Technologies, Inc.) Resonator: CR-760 (manufactured by EM Lab Co., Ltd.) Measurement frequency: Approximately 60 GHz

[0177]

[0178]

[0179]

[0180] From the results in Table 3-1, it can be said that the films obtained from the negative photosensitive resin compositions of Examples 1, 4, and 5 have a lower dielectric constant than the film obtained from the negative photosensitive resin composition of Comparative Example 1. From the results in Table 3-2, it can be said that the films obtained from the negative photosensitive resin compositions of Examples 2 and 3 have a lower dielectric constant than the film obtained from the negative photosensitive resin composition of Comparative Example 2. Furthermore, from the results in Table 3-3, it can be said that the films obtained from the negative photosensitive resin compositions of Examples 6 to 15 have a lower dielectric constant than the film obtained from the negative photosensitive resin composition of Comparative Example 1.

[0181] [Evaluation of Developability] The negative photosensitive resin compositions prepared in Examples 1, 4 to 6, 14, 15, and Comparative Example 3 were applied to an 8-inch silicon wafer using a spin coater (CLEAN TRACK ACT-8, manufactured by Tokyo Electron Ltd.), and then prebaked at 115°C for 270 seconds to form a photosensitive resin film with a film thickness of approximately 6.5 µm on the silicon wafer. An exposure pattern of 7 x 7 mm square (exposure dose: 20 to 720 mJ / cm) was formed on the obtained photosensitive resin film using an i-line stepper (NSR-2205i12D, manufactured by Nikon Corporation). ２ After exposure, an automatic developing apparatus (AD-1200, manufactured by Mikasa Co., Ltd.) was used to perform spray development using cyclopentanone as the developer, and spray rinsing using propylene glycol monomethyl ether acetate (PGMEA) as the rinse solution. The development time with cyclopentanone was 100 times that of the unexposed area of ​​Example 1 (0 mJ / cm ２ The time required for the development of the photosensitive resin film was 30 seconds, which is the time required for complete development, and the rinsing time with PGMEA was 10 seconds. The appearance immediately after development was visually inspected to determine whether or not any unexposed film remained around the exposed pattern. In other words, if no unexposed film remained around the exposed pattern, it means that no radicals were generated at the pre-bake temperature. Conversely, if the unexposed film remained, it means that radicals were generated at the pre-bake temperature and curing was progressing. The results of visually inspecting the photosensitive resin film after development are shown in Table 4. The case where no unexposed film remained was rated as "good," and the case where the unexposed film remained was rated as "poor."

[0182]

[0183] From the results in Table 4, it can be said that the photosensitive resin films obtained from the negative photosensitive resin compositions of Example 1, Example 4 to Example 6, Example 14, and Example 15 have better developability than the photosensitive resin film obtained from the negative photosensitive resin composition of Comparative Example 3.

Claims

1. A photosensitive resin composition for forming an insulating film, comprising: an alkali-insoluble polyimide having a structural unit represented by the following formula (1) and a structural unit represented by the following formula (2); a photoradical polymerization initiator; a crosslinkable compound; a thermal radical generator having a one-minute half-life temperature of 140°C or higher; and a solvent. (In formula (1), A １ represents a tetravalent organic group. ２ represents a divalent aromatic group having a photopolymerizable group.

2. The photosensitive resin composition for forming an insulating film according to claim 1, wherein the thermal radical generator is a compound represented by the following formula (H1): (In formula (H1), R １ represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and when the alkyl group has 3 or more carbon atoms, it is a branched alkyl group; A ３ represents a single bond, a divalent aromatic group or a divalent alicyclic hydrocarbon group, X represents a single bond or a divalent linking group having 1 to 3 carbon atoms, and Z represents a hydrogen atom or a group represented by the following formula (H1-1): ３ and when X is a single bond, R １ represents an alkyl group having 1 to 10 carbon atoms. (In formula (H1-1), R １ , A ３ and X are each defined as in formula (H1), and * represents a bond.

3. In the formula (H1), R １ represents an alkyl group having 1 to 4 carbon atoms; A ３ represents a divalent aromatic group or a divalent alicyclic hydrocarbon group, X represents a divalent linking group having 1 to 3 carbon atoms, and Z represents a hydrogen atom.

4. In the formula (H1), A ３ 4. The photosensitive resin composition for forming an insulating film according to claim 2, wherein represents a phenylene group or a cyclohexylene group, and X represents an isopropylidene group.

5. The photosensitive resin composition for forming an insulating film according to claim 1, wherein the thermal radical generator is a compound represented by the following formula (H2): (In formula (H2), R ２ each independently represents an alkyl group having 1 to 10 carbon atoms, and when the alkyl group has 3 or more carbon atoms, it is a branched alkyl group; A ４ represents a divalent organic group having 2 to 10 carbon atoms, and each X independently represents a single bond or a divalent linking group having 1 to 3 carbon atoms.

6. In the formula (H2), R ２ represents an alkyl group having 1 to 4 carbon atoms; A ４ 6. The photosensitive resin composition for forming an insulating film according to claim 5, wherein represents a phenylene group or a cyclohexylene group, and X represents an isopropylidene group.

7. A photosensitive resin composition for forming an insulating film according to claim 1, 2 or 5, wherein the structural unit represented by formula (2) is a structural unit represented by the following formula (2a): (In formula (2a), V １ represents a direct bond, an ether bond, an ester bond, an amide bond, a urethane bond, or a urea bond; W １ represents an oxygen atom or an NH group, R ２ represents a direct bond or an alkylene group having 2 to 6 carbon atoms which may be substituted with a hydroxy group, R ３ represents a hydrogen atom or a methyl group.

8. In the above formula (2a), V １ represents an ester bond, W １ The photosensitive resin composition for forming an insulating film according to claim 7 , wherein represents an oxygen atom.

9. In the above formula (2a), R ２ 8. The photosensitive resin composition for forming an insulating film according to claim 7, wherein represents a 1,2-ethylene group.

10. A photosensitive resin composition for forming an insulating film according to claim 1, claim 2 or claim 5, wherein the structural unit represented by formula (1) is at least one structural unit selected from the group consisting of the following formulas (1a), (1b) and (1c): (In formula (1c), A ４ represents a divalent organic group having at least two benzene rings.

11. The photosensitive resin composition for forming an insulating film according to claim 1, claim 2 or claim 5, further comprising an adhesion promoter.

12. The photosensitive resin composition for forming an insulating film according to claim 1, claim 2 or claim 5, further comprising an azole compound.

13. An insulating film which is a fired product of a coating film of the photosensitive resin composition for forming an insulating film according to claim 1, 2 or 5.

14. A photosensitive resist film comprising a substrate film, a photosensitive resin layer formed from the photosensitive resin composition for forming an insulating film according to claim 1, claim 2 or claim 5, and a cover film.

15. A method for producing a substrate with a cured relief pattern, comprising: (1) applying a photosensitive resin composition for forming an insulating film according to claim 1, 2 or 5 onto a substrate to form a photosensitive resin layer on the substrate; (2) exposing the photosensitive resin layer to light; (3) developing the exposed photosensitive resin layer to form a relief pattern; and (4) heat-treating the relief pattern to form a cured relief pattern.

16. The method for producing a substrate having a cured relief pattern according to claim 15, wherein the developer used for the development is an organic solvent.

17. A substrate having a cured relief pattern produced by the method of claim 15.

18. A semiconductor device comprising a semiconductor element and a cured film provided on the upper or lower part of the semiconductor element, wherein the cured film is a cured relief pattern formed from the photosensitive resin composition for forming an insulating film according to claim 1, claim 2 or claim 5.

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