Photosensitive resin composition, dry film, cured product, and electronic component

Abstract

Provided: a photosensitive resin composition having a high dissolution rate of an exposed portion and capable of achieving excellent dissolution contrast (resolution). A photosensitive resin composition comprising: (A) a polyimide precursor which is a reaction product of a diamine compound and a dicarboxylic acid, and (B) a photosensitizer, wherein the diamine compound contains at least one selected from the diamine compounds represented by the following general formulas (1) and (2), and the dicarboxylic acid contains at least one selected from carboxylic anhydrides and dicarboxylic acid chlorides. #imgabs0#

Description

[0001] Cross-reference to related applications

[0002] This application claims priority based on Japanese Patent Application No. 2019-183178 filed on October 3, 2019, and Japanese Patent Application No. 2019-183196 filed on October 3, 2019, and the entire disclosures of these are incorporated herein by reference as part of the disclosure of this specification. Technical field

[0003] The present invention relates to: a photosensitive resin composition containing a polyimide precursor having a diamine compound with a specific structure as a polymerization component, a dry film having a resin layer formed from the photosensitive resin composition, a cured product of the photosensitive resin composition, and electronic components such as printed circuit boards and semiconductor elements using the cured product. Background art

[0004] Photosensitive resin compositions containing polyimide precursors exhibit excellent properties such as insulation, heat resistance, and mechanical strength, and are therefore widely used in various fields. For example, applications to flexible printed circuit boards, buffer coating films for semiconductor elements, and insulating films for redistribution layers in wafer-level packaging (WLP) have been advanced.

[0005] Specifically, an alkaline-developable photosensitive resin composition is coated on a substrate and dried to form a coating film. After exposure through a pattern mask, alkaline development is performed using the difference in solubility of the exposed portion and the unexposed portion in an alkaline developer, thereby forming a film with a desired pattern. The film is then heated to cause a ring-closure reaction of the polyimide precursor contained in the photosensitive resin composition, whereby a cured film can be obtained.

[0006] In recent semiconductor elements, with the requirements of high functionality and miniaturization, buffer coating films and insulating films for redistribution layers in wafer-level packaging are required to form cured films with finer patterns, and in photosensitive resin compositions, excellent resolution is also required.

[0007] In order to achieve excellent resolution, in the coating film of the photosensitive resin composition, it is important that the dissolution rate of the exposed portion in the alkaline developer (hereinafter, simply referred to as the exposed portion dissolution rate) is high and the alkali resistance of the unexposed portion in the alkaline developer is high. That is, a photosensitive resin composition with a large difference in dissolution rate between the exposed portion and the unexposed portion in the alkaline developer, so-called dissolution contrast, is sought.

[0008] In response to this requirement, Patent Document 1 discloses a photosensitive polyimide resin composition containing a polyimide precursor, and Patent Document 2 discloses a composition of a photosensitive resin using a polybenzoxazole precursor as having properties equivalent to those of a polyimide resin and having high resolution.

[0009] In addition, a cured film formed from a photosensitive resin composition containing a polyimide precursor sometimes exhibits warping accompanied by a ring-closure reaction. Therefore, in order to suppress warping, a photosensitive resin composition that can be cured even at low temperatures has been proposed (see Patent Document 3).

[0010] Prior Art Documents

[0011] Patent Documents

[0012] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2006-267800

[0013] Patent Document 2: Japanese Unexamined Patent Application Publication No. 2003-241377

[0014] Patent Document 3: Japanese Unexamined Patent Application Publication No. 2018-146964 Summary of the Invention

[0015] Problems to be Solved by the Invention

[0016] However, it cannot be said that the compositions described in Patent Documents 1 and 2 can sufficiently satisfy the dissolution contrast required for achieving the resolution required for recent semiconductor elements. In addition, the compositions described in Patent Document 3 must use high-boiling solvents such as N-methyl-2-pyrrolidone (NMP) and γ-butyrolactone (GBL). Therefore, in addition to the problem of resolution, there is also a problem that high-boiling solvents remain in the cured product.

[0017] Therefore, the main object of the present invention is to provide a photosensitive resin composition containing a polyimide precursor having excellent insulation properties, heat resistance, mechanical strength, etc., and excellent solubility in various solvents (hereinafter, simply referred to as solvent solubility), and also having excellent dissolution contrast (resolution).

[0018] Means for Solving the Problems

[0019] The present inventors focused on obtaining excellent dissolution contrast by increasing the dissolution rate of the exposed portion, and as a result, found that the resolution was significantly improved in a photosensitive resin composition containing a polyimide precursor having a specific structure. In addition, it was found that the polyimide precursor has high solubility in various solvents represented by low-boiling solvents such as 2-methoxy-1-methylethyl acetate (PGMEA) and 4-methyl-2-pentanone (MIBK). The present invention was made based on the above findings.

[0020] The gist of the present invention is as follows.

[0021] [1] A photosensitive resin composition comprising:

[0022] (A) a polyimide precursor which is a reaction product of a diamine compound and a dicarboxylic acid, and

[0023] (B) photosensitizer,

[0024] The diamine compound includes at least one selected from the group consisting of diamine compounds represented by the following general formulas (1) and (2):

[0025]

[0026] (Where,

[0027] A is selected from a single bond, O and a divalent organic group,

[0028] B is a fluoroalcohol group,

[0029] R is a substituted or unsubstituted alkyl or aryl group,

[0030] n1 and n2 are each independently an integer of 0 to 4, and n1+n2 is 1 or greater,

[0031] n3 and n4 are each independently an integer from 0 to 3,

[0032] n5 is an integer from 1 to 4,

[0033] n6 is an integer from 0 to 3.)

[0034] The dicarboxylic acid includes at least one selected from the group consisting of carboxylic anhydrides and dicarboxylic acid chlorides.

[0035] [2] The photosensitive resin composition according to [1], wherein the diamine compound further comprises at least one selected from the group consisting of diamine compounds represented by the following general formulas (3) and (4):

[0036]

[0037] (Where,

[0038] A is selected from a single bond, O and a divalent organic group,

[0039] R is a substituted or unsubstituted alkyl or aryl group,

[0040] n7 and n8 are each independently an integer of 0 to 4, and n7+n8 is 1 or greater,

[0041] n9 and n10 are each independently an integer from 0 to 3,

[0042] n11 is an integer from 1 to 4,

[0043] n12 is an integer from 0 to 3. ).

[0044] [3] The photosensitive resin composition according to [1] or [2], wherein the fluorine concentration in the polyimide precursor (A) is 20 to 200 mol / g.

[0045] [4] The photosensitive resin composition according to any one of [1] to [3], wherein the carboxyl group concentration in the aforementioned (A) polyimide precursor is 300 to 800 mol / g.

[0046] [5] The photosensitive resin composition according to any one of [1] to [4], wherein the hydroxyl group concentration in the aforementioned (A) polyimide precursor is 200 to 600 mol / g.

[0047] [6] The photosensitive resin composition according to any one of [1] to [5], wherein in the aforementioned general formulas (1) and (2), the carbon number of the fluoroalcohol group represented by B is independently 1 to 10, and the fluorine number is independently 1 to 10.

[0048] [7] The photosensitive resin composition according to any one of [1] to [6], further comprising (C) an adhesive.

[0049] [8] The photosensitive resin composition according to any one of [1] to [6], wherein the aforementioned (B) photosensitizer is a diazonaphthoquinone compound.

[0050] [9] A dry film, comprising: a thin film; and a resin layer formed on the aforementioned thin film from the photosensitive resin composition according to any one of [1] to [8].

[0051]

[10] A cured product formed from the photosensitive resin composition according to any one of [1] to [8], or formed from the resin layer of the dry film according to [9].

[0052]

[11] An electronic component, at least comprising the cured product according to

[10] .

[0053] Effects of the Invention

[0054] According to the present invention, it is possible to provide: a photosensitive resin composition having a high dissolution rate in the exposed portion and capable of achieving excellent dissolution contrast (resolution). In addition, the polyimide precursor contained in the photosensitive resin composition has excellent solubility in various solvents represented by low-boiling solvents, and thus, the problem of the above-mentioned residual solvents can be solved. Detailed Embodiments

[0055] [Photosensitive Resin Composition]

[0056] The photosensitive resin composition of the present invention contains (A) a polyimide precursor and (B) a photosensitizer as essential components, and optionally contains other optional components such as a crosslinking agent, a plasticizer, and an adhesive. Hereinafter, each component constituting the photosensitive resin composition of the present invention will be described.

[0057] <(A) Polyimide Precursor>

[0058] Regarding the polyimide precursor, which is a reaction product of a diamine compound and a dicarboxylic acid contained in the photosensitive resin composition, at least one diamine compound selected from the diamine compounds represented by the following general formulas (1) and (2) is included as the diamine compound:

[0059]

[0060] In addition, in an embodiment of the present invention, it is preferable to use in combination at least one selected from the diamine compounds represented by the above general formulas (1) and (2) and at least one diamine selected from the diamine compounds represented by the following general formulas (3) and (4) as the aforementioned diamine compound.

[0061]

[0062] In the above general formulas (1) and (3), A is selected from a single bond, O, and a divalent organic group.

[0063] The carbon number of the divalent organic group is preferably 1 to 10, more preferably 1 to 6, and still more preferably 1 to 3.

[0064] Examples of the divalent organic group include an alkylene group, a cycloalkylene group, an arylene group, an alkyl ether group, a keto group, an ester group, etc.

[0065] More specifically, examples of the divalent organic group include the following, but are not limited thereto. It should be noted that a in the structure is each independently an integer of 0 to 2, and from the viewpoint of solvent solubility, 0 to 1 is preferred, and 0 is particularly preferred. In addition, b in the structure is an integer of 1 to 3, and from the viewpoints of solvent solubility and transparency of the cured product, 2 to 3 is preferred, and 3 is particularly preferred. It should be noted that * represents an atomic bond.

[0066]

[0067] In the above general formulas (1) and (2), B is a fluoroalcohol group.

[0068] The carbon number of the fluoroalcohol group is each independently preferably 1 to 10, more preferably 3 to 6.

[0069] The fluorine number of the fluoroalcohol group is each independently preferably 1 to 10, more preferably 4 to 8. Thereby, the solvent solubility and the transparency of the cured product can be improved.

[0070] Specific examples of the fluoroalcohol group include groups having the following structures, but are not limited thereto. It should be noted that * represents an atomic bond.

[0071]

[0072] In the above general formulas (1) to (4), R is a substituted or unsubstituted alkyl or aryl group.

[0073] The number of carbon atoms of the alkyl group is preferably 1 to 10, more preferably 1 to 6.

[0074] Examples of the alkyl group include methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, n-pentyl, sec-pentyl, n-hexyl, cyclohexyl, fluoromethyl, difluoromethyl, trifluoromethyl, chloromethyl, dichloromethyl, trichloromethyl, bromomethyl, dibromomethyl, tribromomethyl, fluoroethyl, difluoroethyl, trifluoroethyl, chloroethyl, dichloroethyl, trichloroethyl, bromoethyl, dibromoethyl, tribromoethyl, hydroxymethyl, hydroxyethyl, hydroxypropyl, methoxy, ethoxy, n-propoxy, n-butoxy, n-pentyloxy, sec-pentyloxy, n-hexyloxy, cyclohexyloxy, n-heptyloxy, n-octyloxy, n-nonyloxy, n-decyloxy, trifluoromethoxy, methylamino, dimethylamino, trimethylamino, ethylamino, propylamino, etc.

[0075] Examples of the aryl group include phenyl, naphthyl, anthryl, pyrenyl, phenanthryl, biphenyl, etc.

[0076] Examples of the substituent include an alkyl group, an alkyl group having a halogen such as a fluoro group or a chloro group, a halogen group, an amino group, a nitro group, a hydroxy group, a cyano group, a carboxyl group, a sulfonic acid group, etc.

[0077] In the above general formula (1), n1 and n2 are each independently an integer of 0 to 4, preferably an integer of 1 to 2. It should be noted that n1 + n2 is 1 or more.

[0078] In the above general formula (1), n3 and n4 are each independently an integer of 0 to 3, preferably an integer of 0 to 1.

[0079] In the above general formula (2), n5 is an integer of 1 to 4, preferably an integer of 1 to 2.

[0080] In the above general formula (2), n6 is an integer of 0 to 3, preferably an integer of 0 to 1.

[0081] In the above general formula (3), n7 and n8 are each independently an integer of 0 to 4, preferably an integer of 1 to 2. It should be noted that n7 + n8 is 1 or more.

[0082] In the above general formula (3), n9 and n10 are each independently an integer of 0 to 3, preferably an integer of 0 to 1.

[0083] In the above general formula (4), n11 is an integer of 1 to 4, preferably an integer of 1 to 2.

[0084] In the above general formula (4), n12 is an integer of 0 to 3, preferably an integer of 0 to 1.

[0085] Examples of the diamine compound satisfying the above general formula (1) include, but are not limited to, the following.

[0086]

[0087] Examples of the diamine compound satisfying the above general formula (2) include, but are not limited to, the following.

[0088]

[0089] Examples of the diamine compound satisfying the above general formula (3) include, but are not limited to, the following.

[0090]

[0091] Examples of the diamine compound satisfying the above general formula (4) include, but are not limited to, the following.

[0092]

[0093] From the viewpoints of adjusting the dissolution rate during development and improving the ring closure rate during low-temperature curing, the composition ratio of the diamine compounds represented by the general formulas (1) and (2) in the polyimide precursor is preferably 5 to 40 mol%, more preferably 15 to 35 mol%. Thereby, the effects of the present invention can be expected.

[0094] From the viewpoints of adjusting the dissolution rate during development and improving the ring closure rate during low-temperature curing, the composition ratio of the diamine compounds represented by the general formulas (3) and (4) in the polyimide precursor is preferably 10 to 45 mol%, more preferably 15 to 35 mol%.

[0095] The carboxylic anhydride constituting the polyimide precursor is preferably as shown in the following general formula (5).

[0096] The dicarboxylic acid component constituting the (A) polyimide precursor contains at least one selected from carboxylic anhydrides and dicarboxylic acid chlorides.

[0097] As the carboxylic anhydride, the compound represented by the following general formula (5) can be preferably used.

[0098]

[0099] In the above general formula (5), X is a tetravalent organic group.

[0100] Examples of the tetravalent organic group include, but are not limited to, groups having the following structures.

[0101] It should be noted that in the following structures, a is an integer independently selected from 0 to 2, and from the viewpoint of solvent solubility, 0 to 1 is preferred, and 0 is particularly preferred. In addition, b is an integer from 1 to 3, and from the viewpoints of solvent solubility and transparency of the cured product, 2 to 3 is preferred, and 3 is particularly preferred. It should be noted that * represents an atomic bond.

[0102]

[0103] Specific examples of the tetravalent organic group having the above preferred structure include, but are not limited to, groups having the following structures.

[0104]

[0105] Specific examples of the tetravalent organic group having the above preferred structure include, but are not limited to, groups having the following structures.

[0106]

[0107] Among the above tetravalent organic groups, groups having the following structures are particularly preferred from the viewpoints of dissolution rate and dissolution contrast in the exposed part.

[0108]

[0109] The composition ratio of the carboxylic anhydride in the polyimide precursor is preferably 0 to 40 mol%, more preferably 0 to 35 mol%. Thereby, the dissolution rate in the exposed part can be promoted and the resolution can be improved.

[0110] The dicarboxylic acid chloride is preferably a compound represented by the following general formula (6).

[0111]

[0112] In the above general formula (6), Y is selected from a single bond, O, and a divalent organic group. As the divalent organic group, those described above can be used.

[0113] In the above general formula (6), Z is a halogen element, preferably Cl.

[0114] From the viewpoint of suppressing the dissolution rate in the unexposed part, the composition ratio of the carboxylic acid chloride in the polyimide precursor is preferably 10 to 50 mol%, more preferably 15 to 50 mol%.

[0115] Within the range not detrimental to the characteristics of the present invention, the photosensitive resin composition may contain other reactive components.

[0116] For one embodiment of the polyimide precursor which is a reaction product of a diamine compound and a dicarboxylic acid, those represented by the following general formulas (7) and (8) can be exemplified. Note that in the formulas, A, B, R, X, and n1 to n6 are the same as defined above.

[0117]

[0118] As structures satisfying the above general formulas (7) and (8), the following structures can be cited, but are not limited thereto.

[0119]

[0120]

[0121]

[0122]

[0123]

[0124]

[0125]

[0126]

[0127]

[0128]

[0129]

[0130]

[0131]

[0132]

[0133]

[0134]

[0135] From the viewpoint of balancing the solubility of the exposed portion in the alkali developer and the alkali resistance of the unexposed portion, the number average molecular weight (Mn) of the polyimide precursor, which is a reaction product (copolymer) of a diamine compound and a dicarboxylic acid, is preferably 2,000 to 30,000, more preferably 5,000 to 10,000. Further, from the viewpoint of suppressing the generation of cracks in the cured product, the weight average molecular weight (Mw) of the polyimide precursor is preferably 4,000 to 80,000, more preferably 10,000 to 30,000. Furthermore, from the viewpoint of reducing residues and swelling during development, Mw / Mn is preferably 2.0 to 4.0, more preferably 2.3 to 3.0. It should be noted that in this specification, the number average molecular weight and the weight average molecular weight are values obtained by measurement using gel permeation chromatography (GPC) and conversion with standard polystyrene.

[0136] From the viewpoint of heat resistance when forming the cured product, the glass transition temperature (Tg) of the polyimide obtained by subjecting the polyimide precursor to a ring-closure reaction is preferably 180 °C or higher, more preferably 200 °C or higher. It should be noted that in this specification, Tg is a value obtained by differential scanning calorimetry (DSC) in accordance with JIS K 7121.

[0137] From the viewpoints of the dissolution rate and dissolution contrast of the exposed portion, the carboxyl group concentration in the polyimide precursor is preferably 300 to 800 mol / g, more preferably 300 to 600 mol / g.

[0138] From the viewpoints of the dissolution rate and dissolution contrast of the exposed portion, the hydroxyl group concentration in the polyimide precursor is preferably 200 to 600 mol / g, more preferably 300 to 500 mol / g.

[0139] From the viewpoints of solvent solubility and transparency of the cured product, the fluorine concentration in the polyimide precursor is preferably 20 to 200 mol / g, more preferably 50 to 100 mol / g.

[0140] Within the range that does not impair the characteristics of the present invention, the photosensitive resin composition of the present invention optionally contains a structure obtained by ring-closing the above polyimide precursor. However, from the viewpoint of the alkali resistance of the unexposed portion to the alkali developer, the content of the ring-closed structure, that is, the imidization rate, is preferably 50% or less, more preferably 40% or less, and further preferably 20% or less.

[0141] In addition, it optionally contains polymerizable components other than the above diamine compounds and dicarboxylic acids.

[0142] (A) The polyimide precursor can be obtained by a conventionally known method using the above diamine compound and dicarboxylic acid.

[0143] <(B) Photosensitizer>

[0144] The photosensitive resin composition of the present invention contains a photosensitizer. By containing the photosensitizer, the solubility of the photosensitive resin composition in an alkali developer can be adjusted. As the photosensitizer, for example, photoacid generators and photobase generators can be cited. Among these, from the viewpoint of dissolution contrast, photoacid generators are preferred.

[0145] The content of the photosensitizer can be appropriately adjusted. For example, for photoacid generators, it is preferably compounded at a ratio of 0.1 to 30 parts by mass, more preferably 1 to 20 parts by mass, relative to 100 parts by mass of the polyimide precursor. It should be noted that the photosensitive resin composition may contain two or more kinds of photosensitizers.

[0146] A photoacid generator is a compound that generates an acid upon irradiation with light such as ultraviolet light or visible light. For example, diazonaphthoquinone compounds, diarylsulfonium salts, triarylsulfonium salts, dialkylbenzoylmethylsulfonium salts, diaryliodonium salts, aryl diazonium salts, aromatic tetracarboxylic acid esters, aromatic sulfonic acid esters, nitrobenzyl esters, aromatic N-oxyimide methanesulfonates, aromatic sulfonamides, and benzoquinone diazosulfonic acid esters can be cited. One kind can be used alone, or two or more kinds can be used in combination. Among these, from the viewpoint of dissolution contrast, diazonaphthoquinone compounds are preferred.

[0147] Specific examples of the diazonaphthoquinone compound include diazonaphthoquinone adducts of tris(4-hydroxyphenyl)-1-ethyl-4-isopropylbenzene (such as TS533, TS567, TS583, TS593 manufactured by Mitsuhisa Chemical Research Institute Co., Ltd.), diazonaphthoquinone adducts of tetrahydroxybenzophenone (such as BS550, BS570, BS599 manufactured by Mitsuhisa Chemical Research Institute Co., Ltd.), and diazonaphthoquinone adducts of 4-{4-[1,1-bis(4-hydroxyphenyl)ethyl]-α,α-dimethylbenzyl}phenol (such as TKF-428, TKF-528 manufactured by Mitsuhisa Chemical Research Institute Co., Ltd.).

[0148] A photobase generator is a compound whose molecular structure changes or whose molecules are cleaved upon irradiation with light such as ultraviolet light or visible light to generate one or more basic substances (such as secondary amines and tertiary amines).

[0149] As the photobase generator, it can be an ionic photobase generator or a non-ionic photobase generator. However, from the viewpoint of the sensitivity of the photosensitive resin composition, an ionic photobase generator is preferred.

[0150] Examples of the ionic photobase generator include salts of carboxylic acids containing aromatic components and tertiary amines. Commercially available products thereof include WPBG-082, WPBG-167, WPBG-168, WPBG-266, and WPBG-300 of ionic PBG manufactured by Wako Pure Chemical Industries, Ltd.

[0151] Examples of the nonionic photo-base generator include α-aminopropiophenone compounds, oxime ester compounds, and compounds having substituents such as N-formyl aromatic amino groups, N-acyl aromatic amino groups, nitrobenzyl carbamate groups, and alkoxybenzyl carbamate groups.

[0152] Examples of other photo-base generators include WPBG-018 (trade name: 9-anthrylmethyl N,N'-diethylcarbamate), WPBG-027 (trade name: (E)-1-[3-(2-hydroxyphenyl)-2-propenoyl]piperidine), WPBG-140 (trade name: 1-(anthraquinon-2-yl)ethyl imidazolecarboxylate), and WPBG-165, etc., manufactured by Wako Pure Chemical Industries, Ltd.

[0153] [Crosslinking agent]

[0154] The photosensitive resin composition of the present invention optionally contains a crosslinking agent. By adding a crosslinking agent, the curing temperature of the photosensitive resin composition can be reduced. The crosslinking agent is not particularly limited, and known and commonly used crosslinking agents can be cited, but compounds capable of reacting with carboxyl groups in the polyimide precursor to form a crosslinked structure are preferred.

[0155] Examples of the compound that reacts with the hydroxyl group in the polyimide precursor or polyimide include crosslinking agents having a cyclic ether group such as an epoxy group, a cyclic thioether group such as a thiirane group, crosslinking agents having an alcoholic hydroxyl group in which a hydroxyl group is bonded to an alkylene group having 1 to 12 carbon atoms such as a hydroxymethyl group, compounds having an ether bond such as an alkoxymethyl group, crosslinking agents having a triazine ring structure, and urea-based crosslinking agents. One kind can be used alone, or two or more kinds can be used in combination. Among these, crosslinking agents having a cyclic ether group, particularly those having an epoxy group, and crosslinking agents having an alcoholic hydroxyl group, particularly those having a hydroxymethyl group to which a hydroxyl group is bonded, are preferred.

[0156] Among the above crosslinking agents, the crosslinking agent having an epoxy group undergoes a thermal reaction with the hydroxyl group of the polyimide precursor or polyimide to form a crosslinked structure. The number of functional groups of the crosslinking agent having an epoxy group is preferably 2 to 4. By including the crosslinking agent having an epoxy group in the photosensitive resin composition, low-temperature curability can be obtained, and the dissolution contrast of the formed dry film can be further improved.

[0157] Among the crosslinking agents having an epoxy group, an epoxy compound having a naphthalene skeleton and having two or more functional groups is preferred. Not only can an insulating film having more excellent flexibility and chemical resistance be obtained, but also a reduction in CTE, which is in a contradictory relationship with flexibility, can be achieved, and warping and cracking of the insulating film can be suppressed. In addition, from the viewpoint of flexibility, a bisphenol A type epoxy compound can also be suitably used.

[0158] In addition, as the crosslinking agent having a hydroxymethyl group, those having two or more hydroxymethyl groups are preferred, and compounds represented by the following general formula (9) are more preferred.

[0159]

[0160] In the above formula, R A1 represents an organic group having a valence of 2 to 10, preferably an alkylene group having 1 to 3 carbon atoms which may optionally have a substituent. In addition, R A2 each independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, preferably a hydrogen atom. In addition, r represents an integer of 2 to 10, preferably an integer of 2 to 4, more preferably 2.

[0161] In addition, the crosslinking agent having a hydroxymethyl group preferably has a fluorine atom, and more preferably has a trifluoromethyl group. It is preferred that the organic group having a valence of 2 to 10 represented by R A1 in the above general formula (9) has the above fluorine atom or the above trifluoromethyl group, and R A1 is preferably bis(trifluoromethyl)methylene. In addition, the crosslinking agent having a hydroxymethyl group preferably has a bisphenol structure, and more preferably has a bisphenol AF structure.

[0162] The compounding amount of the crosslinking agent is preferably 0.1 to 30 parts by mass, more preferably 0.1 to 20 parts by mass, based on 100 parts by mass of the non-volatile component of the polyimide precursor.

[0163] [Plasticizer]

[0164] The photosensitive resin composition of the present invention optionally contains a plasticizer. By including a plasticizer, the plasticizing effect, i.e., the aggregation effect between polymer molecular chains, is reduced, and the mobility and flexibility between molecular chains are improved. As a result, it is considered that the thermal molecular motion of the polyimide precursor is improved, the cyclization reaction is promoted, and low-temperature curability is imparted. As the plasticizer, there is no particular limitation as long as it is a compound that improves plasticization, and examples thereof include bifunctional (meth)acrylic acid compounds, sulfonamide compounds, phthalate compounds, maleate compounds, aliphatic dicarboxylic acid esters, phosphate esters, and ether compounds such as crown ethers. One kind can be used alone, or two or more kinds can be used in combination. Among these, bifunctional (meth)acrylic acid compounds are preferred. The bifunctional (meth)acrylic acid compound is preferably a compound that does not form a crosslinked structure with other components in the composition. In addition, from the viewpoint of further alleviating the internal stress of the cured product, the bifunctional (meth)acrylic acid compound is preferably a compound that forms a linear structure by self-polymerization.

[0165] Among the bifunctional (meth)acrylic acid compounds, the bis(meth)acrylate of an alkylene oxide adduct of a diol (such as ethylene oxide and propylene oxide) and a bifunctional polyester (meth)acrylate are preferred, and the bifunctional polyester (meth)acrylate is more preferred.

[0166] As the bis(meth)acrylate of an alkylene oxide adduct of a diol, specifically, those obtained by adding (meth)acrylate to the terminal after modifying the diol with an alkylene oxide are preferred, and those having an aromatic ring in the diol are more preferred. For example, bisphenol A EO (ethylene oxide) adduct diacrylate, bisphenol A PO (propylene oxide) adduct diacrylate, etc. can be cited. The specific structure of the bis(meth)acrylate of an alkylene oxide adduct of a diol is shown in the following general formula (10), but is not limited thereto.

[0167]

[0168] In the above formula, p + q is 2 or more, preferably 2 to 40, more preferably 3.5 to 25.

[0169] The blending amount of the plasticizer is not particularly limited, and is preferably 3 to 40 parts by mass relative to 100 parts by mass of the non-volatile components of the polyimide precursor.

[0170] <(C) Adhesive>

[0171] The photosensitive resin composition of the present invention preferably contains an adhesive. By including an adhesive, the adhesiveness to a substrate or the like can be improved. As the adhesive, a silane coupling agent, a titanate coupling agent, and an aluminum coupling agent can be used.

[0172] As silane coupling agents, examples include N-phenyl-3-aminopropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltriethoxysilane, γ-acryloxypropyltrimethoxysilane, γ-acryloxypropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, 3-ureidopropyltrialkoxysilane, phenyltrimethoxysilane, and the like.

[0173] As titanate coupling agents, examples include triisooctanoyl titanate isopropyl ester, isopropyl tridecylbenzenesulfonyl titanate, isopropyl tris(dioctylpyrophosphate acyloxy)titanate, tetraisopropyl bis(dioctylphosphite acyloxy)titanate, tetraoctyl bis(di(tridecyl)phosphite acyloxy)titanate, tetra(2,2-diallyloxymethyl) bis(di-tridecyl)phosphite acyloxy titanate, bis(dioctylpyrophosphate acyloxy)oxyacetate titanate, bis(dioctylpyrophosphate acyloxy)ethylene titanate, and the like.

[0174] As aluminum coupling agents, examples include diisopropyl acetylalkoxyaluminum, and the like.

[0175] The above-mentioned adhesives can be used alone or in combination of two or more. Among the above-mentioned adhesives, from the viewpoint of improving the adhesion to the substrate without adversely affecting the development speed, N-phenyl-3-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, and 3-ureidopropyltriethoxysilane are preferred.

[0176] The compounding amount of the adhesive is not particularly limited, and is preferably 0.1 to 10 parts by mass relative to 100 parts by mass of the non-volatile component of the polyimide precursor.

[0177] [Thermal acid generator, sensitizer, other components]

[0178] In the photosensitive resin composition of the present invention, within the range not impairing the effects of the present invention, in order to promote the cyclization reaction of the polyimide precursor, a known thermal acid generator is optionally further included, and in order to improve the photosensitivity, a known sensitizer and the like are optionally further included. In addition, in order to impart processing characteristics and various functions to the photosensitive resin composition of the present invention, various organic or inorganic low-molecular or high-molecular compounds can be further compounded. For example, commonly used known surfactants, leveling agents, fine particles, and the like can be used. As the fine particles, organic fine particles such as polystyrene and polytetrafluoroethylene, and inorganic fine particles such as silica, carbon, and layered silicate can be cited. In addition, the photosensitive resin composition of the present invention can contain various colorants and fibers, and the like.

[0179] [Solvent]

[0180] The photosensitive resin composition of the present invention optionally contains a solvent. There is no particular limitation on the solvent, and it can be used without particular limitation as long as it can dissolve the above polyimide precursor. If the residual property when the temperature for heating and curing the coating film of the photosensitive resin composition after exposure / development is considered to be reduced, a solvent having a boiling point of 200 °C or lower is preferred.

[0181] Examples of the solvent having a boiling point of 200 °C or lower include 2-methoxy-ethyl acetate (PGMEA), 4-methyl-2-pentanone (MIBK), N-methylcaprolactam, dimethyl sulfoxide, tetramethylurea, pyridine, dimethyl sulfone, hexamethyl sulfoxide, ethyl acetate, butyl acetate, ethyl lactate, methyl 3-methoxypropionate, methyl 2-methoxypropionate, ethyl 3-methoxypropionate, ethyl 2-methoxypropionate, ethyl 3-ethoxypropionate, ethyl 2-ethoxypropionate, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol methyl ether, propylene glycol dimethyl ether, dipropylene glycol dimethyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, propylene glycol monomethyl ether acetate, carbitol acetate, ethyl cellosolve acetate, cyclohexanone, methyl ethyl ketone, methyl isobutyl ketone, and 2-heptanone. One kind can be used alone, or two or more kinds can be used in combination.

[0182] There is no particular limitation on the content of the solvent in the photosensitive resin composition, and it can be appropriately changed according to its use. For example, relative to 100 parts by mass of the polyimide precursor contained in the photosensitive resin composition, it can be set to 200 to 2000 parts by mass or less.

[0183] [Dry film]

[0184] The dry film of the present invention includes: a support; and a resin layer formed of the photosensitive resin composition provided on the support. As an embodiment of the present invention, for the dry film, for the purpose of preventing dust from adhering to the surface of the resin layer, etc., a protective layer that can be detachably provided can be provided on the surface of the resin layer.

[0185] There is no particular limitation on the support, and for example, a film formed of a thermoplastic resin such as polyethylene terephthalate and polyethylene naphthalate, a polyimide film, a polyamideimide film, a polypropylene film, and a polystyrene film can be used. Among these, polyethylene terephthalate is preferred from the viewpoints of heat resistance, mechanical strength, and workability. In addition, a laminate of these films can also be used as the support.

[0186] From the viewpoint of improving mechanical strength, the above thermoplastic resin film is preferably a film stretched in a uniaxial direction or a biaxial direction.

[0187] The thickness of the support is not particularly limited and can be set, for example, to 10 to 150 μm.

[0188] The resin layer provided on the support can be formed as follows: by using a known coating means, the above-mentioned photosensitive resin composition is coated on the support to form a uniform thickness, a coating film is formed, and the coating film is dried, thereby forming the resin layer. As the coating means, there is no particular limitation, and examples thereof include comma coater, knife coater, lip coater, bar coater, roll coater, reverse coater, transfer roll coater, gravure coater, and spray coater.

[0189] In addition, in other embodiments, the resin layer can be formed by coating the photosensitive resin composition on the protective layer in the same manner as above and drying.

[0190] The thickness of the resin layer is not particularly limited and can be appropriately changed according to the use. For example, it can be set to 1 to 150 μm.

[0191] As the protective layer that can be provided so as to be peelable from the resin layer, as long as the adhesive force between the resin layer and the protective layer is less than the adhesive force between the support and the resin layer when the protective layer is peeled off, there is no particular limitation. For example, polyethylene film, polytetrafluoroethylene film, polypropylene film, and surface-treated paper can be used.

[0192] The thickness of the protective layer is not particularly limited and can be set, for example, to 10 to 150 μm.

[0193] [Cured product]

[0194] By curing the above-mentioned photosensitive resin composition or the resin layer of the dry film, a cured product can be obtained. The cured product can form a desired patterned shape. Hereinafter, a method for obtaining the cured product of the present invention is exemplified, but it is not limited thereto.

[0195] [First step]

[0196] The method for manufacturing the cured product of the present invention includes the following steps: coating the photosensitive resin composition on a substrate to form a coating film, drying the coating film, or transferring the resin layer from the above dry film to the substrate to form a dried coating film.

[0197] As the base material, in addition to printed circuit boards and flexible printed circuit boards that have circuits formed in advance from copper or the like, the following can be cited: copper-clad laminates of all grades (such as FR-4), metal substrates, polyimide films, polyethylene terephthalate films, polyethylene naphthalate (PEN) films, glass substrates, ceramic substrates, wafer boards, etc. The copper-clad laminates use materials such as paper phenol resin, paper epoxy resin, glass cloth epoxy resin, glass polyimide resin, glass cloth / non-woven fabric epoxy resin, glass cloth / paper epoxy resin, synthetic fiber epoxy resin, and copper-clad laminates for high-frequency circuits using fluororesin / polyethylene / polyphenylene oxide / cyanate ester, etc.

[0198] As a method for coating the photosensitive resin composition on the base material, the above methods can be cited.

[0199] As a drying method, methods such as air drying, heat drying using an oven or hot plate, and vacuum drying can be cited.

[0200] The drying of the coating film is desirably carried out under conditions that do not cause the ring closure of the polyimide precursor in the photosensitive resin composition. Specifically, it is preferably carried out by natural drying, air blowing drying, or heat drying at 70 to 140 °C for 1 to 30 minutes. In addition, since the operation method is simple, it is preferably dried using a hot plate for 1 to 20 minutes. In addition, vacuum drying can also be carried out. In this case, it can be carried out at room temperature for 20 minutes to 1 hour.

[0201] The transfer of the dry film onto the base material is preferably carried out under pressure and heating using a vacuum laminator or the like. By using such a vacuum laminator, when using a substrate with a formed circuit, even if there are irregularities on the surface of the circuit board, the resin layer of the dry film fills the irregularities of the circuit board under vacuum conditions, so there is no mixing of air bubbles, and in addition, the hole filling property of the concave portions on the substrate surface is also improved.

[0202] [Second process]

[0203] Next, the above coating film is selectively irradiated with active energy rays through a patterned photomask, or non-selectively irradiated without a photomask.

[0204] As the active energy rays, for example, wavelength active energy rays that can activate the photoacid generator as the (B) photosensitizer are used. Specifically, the active energy rays preferably have a maximum wavelength in the range of 350 to 410 nm.

[0205] The exposure amount varies depending on the film thickness, etc., and can generally be set to 10 to 1000 mJ / cm 2 and preferably can be set to 20 to 800 mJ / cm 2 within the range.

[0206] As the exposure apparatus used in the above-mentioned actinic ray irradiation, any apparatus that irradiates ultraviolet rays in the range of 350 to 450 nm by mounting a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a metal halide lamp, a mercury short-arc lamp, etc. can be used. Furthermore, a direct drawing apparatus (for example, a laser direct imaging apparatus that directly draws an image with a laser using CAD data from a computer) can also be used.

[0207] [Step 3]

[0208] If necessary, by heating the coating film for a short time, a part of the polyimide precursor in the unexposed portion can be cyclized. Here, the cyclization rate is about 30%. The heating time and heating temperature are appropriately changed according to the type of polyimide precursor, the coating film thickness, and the type of (B) photosensitizer.

[0209] [Step 4]

[0210] Next, the above-mentioned exposed coating film is treated with a developer to remove the exposed portion in the coating film, thereby obtaining a pattern film.

[0211] In this step, any method can be selected from conventionally known photoresist development methods, such as spin coating method, paddle method, dipping method with ultrasonic treatment, etc.

[0212] As the developer, aqueous solutions of inorganic bases such as sodium hydroxide, sodium carbonate, sodium silicate, ammonia water, etc., organic amines such as ethylamine, diethylamine, triethylamine, triethanolamine, etc., quaternary ammonium salts such as tetramethylammonium hydroxide, tetrabutylammonium hydroxide, etc. can be cited. In addition, if necessary, an appropriate amount of water-soluble organic solvents such as methanol, ethanol, isopropanol, etc. and surfactants can be added to them.

[0213] After development, if necessary, the coating film is washed with a rinsing solution to obtain a pattern film. As the rinsing solution, distilled water, methanol, ethanol, isopropanol, etc. can be used alone or in combination. In addition, the above solvents can be used as the developer.

[0214] [Step 5]

[0215] Next, by heating the pattern film, a cured coating film (cured product) can be obtained. Through the heating step, the polyimide precursor contained in the photosensitive resin composition undergoes a cyclization reaction to become polyimide.

[0216] From the viewpoint of preventing warping of the cured product, the heating temperature is preferably 120 to 250 °C, more preferably 150 to 200 °C. During heating, for example, a hot plate, an oven, and a temperature-programmable heating oven can be used. In addition, the heating atmosphere (gas) can be under air or under an inert gas such as nitrogen or argon.

[0217] [Use]

[0218] The use of the photosensitive resin composition of the present invention is not particularly limited. For example, it can be suitably used as a forming material for coatings, printing inks, adhesives, display devices, semiconductor elements, electronic components, optical components, building materials, etc.

[0219] Specifically, as a forming material for display devices, layer forming materials and image forming materials in color filters, films for flexible displays, resist materials, alignment films, etc. can be cited.

[0220] As a forming material for semiconductor elements, layer forming materials in resist materials, buffer coating films, insulating films for redistribution layers of wafer-level packaging (WLP), etc. can be cited.

[0221] As a forming material for electronic components, sealing materials and layer forming materials in printed circuit boards, interlayer insulating films, and wiring coating films, etc. can be cited.

[0222] In addition, as a forming material for optical components, optical materials and layer forming materials in holograms, optical waveguides, optical circuits, optical circuit components, antireflection films, etc. can be cited.

[0223] Furthermore, as a building material, it can be used for coatings, coating agents, etc.

[0224] The photosensitive resin composition of the present invention is mainly used as a pattern forming material, and particularly can be suitably used as a surface protective film, buffer coating film, interlayer insulating film, insulating film for rewiring, protective film for flip chip devices, protective film for devices with a bump structure, interlayer insulating film for multilayer circuits, insulating material for passive components, solder resist, protective film for printed circuit boards such as cover films, and liquid crystal alignment films, etc.

[0225] Examples

[0226] Hereinafter, the present invention will be described in more detail using examples, but the present invention is not limited to the examples. It should be noted that in the following, "parts" and "%" are all based on mass unless otherwise specified.

[0227] (Reference Example 1: Synthesis of Copolymer A-1)

[0228] Into a 0.5-liter flask equipped with a stirrer and a thermometer, 64 g of N-methylpyrrolidone was charged, and 4.23 g (7.98 mmol) of 3,3'-bis(1-hydroxy-1-trifluoromethyl-2,2,2-trifluoroethyl)-4,4'-methylenedianiline (HFA-MDA) and 2.92 g (7.98 mmol) of bis(3-amino-4-hydroxyphenyl)hexafluoropropane (6FAP) were stirred and dissolved.

[0229]

[0230] After confirming that the monomer was completely dissolved, 3.12 g (7.02 mmol) of 4,4'-(hexafluoroisopropylidene)diphthalic anhydride (6FDA) was added over 5 minutes while keeping the solid unchanged, and stirring was continued at room temperature for 1 hour.

[0231]

[0232] After that, the flask was immersed in an ice bath, and while maintaining the temperature inside the flask at 0 to 5 °C, 2.07 g (7.02 mmol) of 4,4'-oxydiphthaloyl dichloride (DEDC) was added while keeping the solid unchanged, and stirring was carried out in the ice bath for 30 minutes. After that, stirring was continued at room temperature for 4 hours.

[0233]

[0234] 0.63 g (3.83 mmol) of 5-norbornene-2,3-dicarboxylic anhydride was added while keeping the solid unchanged to the stirred solution, and stirring was carried out at room temperature for 16 hours. The stirred solution was poured into 400 mL of ion-exchanged water (resistivity value 18.2 MΩ·cm), and the precipitated product was recovered.

[0235] After recovering the precipitated product, drying was carried out under reduced pressure to obtain copolymer A-1 having a carboxyl terminal and having the following repeating structure. The number-average molecular weight (Mn) of copolymer A-1 was 6070, the weight-average molecular weight (Mw) was 15780, and Mw / Mn was 2.60. In addition, the carboxyl concentration of the obtained copolymer A-1 was 586 g / mol, the hydroxyl concentration was 391 g / mol, and the fluorine concentration was 81 g / mol.

[0236]

[0237] (Reference Example 2: Synthesis of Copolymer A-2)

[0238] In a 0.5 L flask equipped with a stirrer and a thermometer, 69 g of N-methylpyrrolidone was charged, and 2.59 g (4.88 mmol) of HFA-MDA and 4.17 g (11.38 mmol) of 6FAP were dissolved by stirring.

[0239] After confirming that the monomers were completely dissolved, 5.10 g (9.62 mmol) of 5,5'-[1-methyl-1,1-ethanediylbis(1,4-phenylene)dioxy]bis(isobenzofuran-1,3-dione) (BPADA) was added over 5 minutes while keeping the solid unchanged, and stirring was continued at room temperature for 1 hour.

[0240]

[0241] After that, the flask was immersed in an ice bath. While maintaining the temperature inside the flask at 0 to 5 °C, 1.22 g (4.12 mmol) of DEDC was added while keeping the solid unchanged, and the mixture was stirred in the ice bath for 30 minutes. After that, stirring was continued at room temperature for 4 hours. While keeping the solid unchanged, 0.82 g (5.01 mmol) of 5-norbornene-2,3-dicarboxylic anhydride was added to the stirred solution, and the mixture was stirred at room temperature for 16 hours. The stirred solution was poured into 400 mL of ion-exchanged water (resistivity value 18.2 MΩ·cm), and the precipitated product was recovered.

[0242] After recovering the precipitated product, drying under reduced pressure was carried out to obtain copolymer A-2 having a carboxyl terminal and having the following repeating structure. The number-average molecular weight (Mn) of copolymer A-2 was 5000, the weight-average molecular weight (Mw) was 13150, and Mw / Mn was 2.63. In addition, the carboxyl concentration of the obtained copolymer A-2 was 550 g / mol, the hydroxyl concentration was 423 g / mol, and the fluorine concentration was 54 g / mol.

[0243]

[0244] (Reference Example 3: Synthesis of Copolymer A-3)

[0245] In a 0.5 L flask equipped with a stirrer and a thermometer, 62 g of N-methylpyrrolidone was charged, and 5.85 g (11.04 mmol) of HFA-MDA and 1.73 g (4.73 mmol) of 6FAP were stirred and dissolved.

[0246] After confirming that the monomers were completely dissolved, 1.32 g (4.27 mmol) of hydroxyphthalic anhydride (ODPA) was added in 5 minutes while keeping the solid unchanged, and stirring was continued at room temperature for 1 hour. After that, the flask was immersed in an ice bath. While maintaining the temperature inside the flask at 0 to 5 °C, 2.94 g (9.96 mmol) of DEDC was added while keeping the solid unchanged, and the mixture was stirred in the ice bath for 30 minutes. After that, stirring was continued at room temperature for 4 hours. While keeping the solid unchanged, 0.51 g (3.09 mmol) of 5-norbornene-2,3-dicarboxylic anhydride was added to the stirred solution, and the mixture was stirred at room temperature for 16 hours. The stirred solution was poured into 400 mL of ion-exchanged water (resistivity value 18.2 MΩ·cm), and the precipitated product was recovered.

[0247]

[0248] After recovering the precipitate, drying under reduced pressure was performed to obtain copolymer A-3 having a carboxyl terminal and the following repeating structure. The number average molecular weight (Mn) of copolymer A-3 was 7,080, the weight average molecular weight (Mw) was 18,120, and Mw / Mn was 2.56. In addition, the carboxyl concentration of the obtained copolymer A-3 was 621 g / mol, the hydroxyl concentration was 365 g / mol, and the fluorine concentration was 74 g / mol.

[0249]

[0250] (Reference Example 4: Synthesis of Copolymer A-4)

[0251] In a 0.5 L flask equipped with a stirrer and a thermometer, 60 g of N-methylpyrrolidone was charged, and 4.26 g (8.04 mmol) of HFA-MDA and 2.94 g (8.04 mmol) of 6FAP were stirred and dissolved.

[0252] After confirming that the monomers were completely dissolved, the flask was immersed in an ice bath, and while maintaining the inside of the flask at 0 to 5 °C, 4.11 g (13.92 mmol) of DEDC was added while keeping it solid, and it was stirred in the ice bath for 30 minutes. Thereafter, stirring was continued at room temperature for 4 hours. 0.71 g (4.31 mmol) of 5-norbornene-2,3-dicarboxylic anhydride was added while keeping it solid in the stirred solution, and it was stirred at room temperature for 16 hours. The stirred solution was poured into 400 mL of ion-exchanged water (resistivity value 18.2 MΩ·cm), and the precipitate was recovered.

[0253] After recovering the precipitate, drying under reduced pressure was performed to obtain copolymer A-4 having a carboxyl terminal and the following repeating structure. The number average molecular weight (Mn) of copolymer A-4 was 3,990, the weight average molecular weight (Mw) was 10,090, and Mw / Mn was 2.53. In addition, the carboxyl concentration of the obtained copolymer A-4 was 0 g / mol, the hydroxyl concentration was 336 g / mol, and the fluorine concentration was 82 g / mol.

[0254]

[0255] (Reference Example 5: Synthesis of Copolymer A-5)

[0256] In a 0.5 L flask equipped with a stirrer and a thermometer, 53 g of N-methylpyrrolidone was charged, and 13.95 g (26.30 mmol) of HFA-MDA was stirred and dissolved.

[0257] After confirming that the monomer was completely dissolved, 13.95 g (26.30 mmol) of 5,5’-[1-methyl-1,1-ethanediylbis(1,4-phenylene)dioxy]bis(isobenzofuran-1,3-dione) (BPADA) was added while keeping the solid unchanged over 5 minutes, and the mixture was continuously stirred at room temperature for 1 hour.

[0258] After that, 0.85 g (5.19 mmol) of 5-norbornene-2,3-dicarboxylic anhydride was added while keeping the solid unchanged to the stirred solution, and the mixture was stirred at room temperature for 16 hours. The stirred solution was poured into 1 L of ion-exchanged water (resistivity value 18.2 MΩ·cm), and the precipitate was recovered.

[0259] After recovering the precipitate, drying under reduced pressure was carried out to obtain copolymer A-5 having norbornene terminals and having the following repeating structure. The number-average molecular weight (Mn) of copolymer A-5 was 6800, the weight-average molecular weight (Mw) was 16790, and Mw / Mn was 2.47. In addition, the carboxyl concentration of the obtained copolymer A-5 was 525 g / mol, and the fluorine concentration was 88 g / mol.

[0260]

[0261] (Reference Example 6: Synthesis of copolymer A-6)

[0262] Into a 0.5 L flask equipped with a stirrer and a thermometer, 53 g of N-methylpyrrolidone was charged, and 14.40 g (26.45 mmol) of HFA-MDA was stirred and dissolved.

[0263] After confirming that the monomer was completely dissolved, 10.46 g (23.55 mmol) of 6FDA was added while keeping the solid unchanged over 10 minutes, and the mixture was continuously stirred at room temperature for 1 hour.

[0264] After that, 0.96 g (5.82 mmol) of 5-norbornene-2,3-dicarboxylic anhydride was added while keeping the solid unchanged to the stirred solution, and the mixture was stirred at room temperature for 16 hours.

[0265] The stirred solution was poured into 1 L of ion-exchanged water (resistivity value 18.2 MΩ·cm), and the precipitate was recovered.

[0266] After recovering the precipitate, drying under reduced pressure was carried out to obtain copolymer A-6 having norbornene terminals and having the following repeating structure. The number-average molecular weight (Mn) of copolymer A-6 was 8700, the weight-average molecular weight (Mw) was 22100, and Mw / Mn was 2.54. In addition, the carboxyl concentration of the obtained copolymer A-6 was 494 g / mol, and the fluorine concentration was 55 g / mol.

[0267]

[0268] (Reference Example 7: Synthesis of Copolymer A-7)

[0269] In a 0.5 L flask equipped with a stirrer and a thermometer, 150 g of N-methylpyrrolidone was charged, and 8.43 g (15.91 mmol) of HFA-MDA was stirred and dissolved.

[0270] After confirming complete dissolution of the monomers, 1.88 g (4.23 mmol) of 6FDA and 5.14 g (9.87 mmol) of BPADA were added in 10 minutes while keeping the solids unchanged, and stirring was continued at room temperature for 1 hour.

[0271] After that, 0.59 g (3.62 mmol) of 5-norbornene-2,3-dicarboxylic anhydride was added to the stirred solution while keeping the solids unchanged, and stirring was carried out at room temperature for 16 hours.

[0272] The stirred solution was poured into ion-exchanged water (resistivity value 18.2 MΩ·cm) in 1 L, and the precipitate was recovered.

[0273] After recovering the precipitate, drying under reduced pressure was carried out to obtain Copolymer A-7 having a norbornenyl end and having the following repeating structure. The number-average molecular weight (Mn) of Copolymer A-7 was 9500, the weight-average molecular weight (Mw) was 24800, and Mw / Mn was 2.61. In addition, the carboxyl concentration of the obtained Copolymer A-7 was 514 g / mol, and the fluorine concentration was 73 g / mol.

[0274]

[0275] (Reference Example 8: Synthesis of Copolymer A-8)

[0276] In a 0.5 L flask equipped with a stirrer and a thermometer, 150 g of N-methylpyrrolidone was charged, and 8.33 g (15.71 mmol) of HFA-MDA was stirred and dissolved.

[0277] After confirming complete dissolution of the monomers, 1.33 g (4.29 mmol) of ODPA and 5.21 g (10.01 mmol) of BPADA were added in 10 minutes while keeping the solids unchanged, and stirring was continued at room temperature for 1 hour.

[0278] After that, 0.46 g (2.82 mmol) of 5-norbornene-2,3-dicarboxylic anhydride was added to the stirred solution while keeping the solids unchanged, and stirring was carried out at room temperature for 16 hours. The stirred solution was poured into ion-exchanged water (resistivity value 18.2 MΩ·cm) in 1 L, and the precipitate was recovered.

[0279] After recovering the precipitate, drying under reduced pressure was carried out to obtain copolymer A-8 having a norbornene end and having the following repeating structure. The number-average molecular weight (Mn) of copolymer A-8 was 10,200, the weight-average molecular weight (Mw) was 24,680, and Mw / Mn was 2.42. In addition, the carboxyl concentration of the obtained copolymer A-8 was 494 g / mol and the fluorine concentration was 82 g / mol.

[0280] (Reference Example 9: Synthesis of Copolymer A-9)

[0281] In a 0.5 L flask equipped with a stirrer and a thermometer, 100 g of N-methylpyrrolidone was charged, and 5.16 g (25.75 mmol) of diaminodiphenyl ether was stirred and dissolved.

[0282] After confirming that the monomers were completely dissolved, 5.29 g (24.25 mmol) of pyromellitic dianhydride (PMDA) was added over 5 minutes while maintaining the solid state, and stirring was continued at room temperature for 1 hour. Thereafter, 0.49 g (2.98 mmol) of 5-norbornene-2,3-dicarboxylic anhydride was added to the stirred solution while maintaining the solid state, and stirring was carried out at room temperature for 16 hours. The stirred solution was poured into 600 mL of ion-exchanged water (resistivity value 18.2 MΩ·cm), and the precipitate was recovered.

[0283]

[0284] After recovering the precipitate, drying under reduced pressure was carried out to obtain copolymer A-9 having a carboxyl end and having the following repeating structure. The number-average molecular weight (Mn) of copolymer A-9 was 6,800, the weight-average molecular weight (Mw) was 17,000, and Mw / Mn was 2.51. In addition, the carboxyl concentration of the obtained copolymer A-9 was 210 g / mol, the hydroxyl concentration was 0 g / mol, and the fluorine concentration was 0 g / mol.

[0285]

[0286] (Reference Example 10: Synthesis of Polybenzoxazole Precursor)

[0287] In a 0.5 L flask equipped with a stirrer and a thermometer, 10.0 g (27.3 mmol) of bis(3-amino-4-hydroxyphenyl)hexafluoropropane was stirred and dissolved in 1500 g of N-methylpyrrolidone.

[0288] Thereafter, the flask was immersed in an ice bath, and while maintaining the inside of the flask at 0 to 5°C and while maintaining the solid state, 8.78 g (29.8 mmol) of 4,4'-diphenylether dichloride was added over 10 minutes, and stirring was carried out in the ice bath for 30 minutes.

[0289] Thereafter, stirring was continued for 18 hours at room temperature. The stirred solution was put into 700 mL of ion-exchanged water (resistivity value: 18.2 MΩ·cm), and the precipitate was recovered.

[0290] Thereafter, the obtained solid was dissolved in 420 mL of acetone and put into 1 L of ion-exchanged water. After the precipitated solid was recovered, it was dried under reduced pressure to obtain a carboxyl-terminated polybenzoxazole precursor. Mw was 29,500, Mn was 11,600, and Mw / Mn was 2.54. In addition, the carboxyl concentration of the obtained polybenzoxazole precursor was 0 g / mol, the hydroxyl concentration was 295 g / mol, and the fluorine concentration was 98 g / mol.

[0291] For each of the copolymers A-1 to A-10 obtained as described above, the ratios of the constituent components (diamine component, dicarboxylic acid component) are summarized in Table 1.

[0292] [Table 1]

[0293]

[0294] <Example 1>

[0295] The copolymer A-1 obtained in Reference Example 1 above was made to be 100 parts by mass, the diazonaphthoquinone compound (manufactured by Sambo Chemical Laboratories Co., Ltd., TKF-528) was made to be 20 parts by mass, the adhesion promoter (manufactured by Shin-Etsu Chemical Co., Ltd., KBM-573) was made to be 5 parts by mass, and PGMEA was made to be 400 parts by mass. They were put into a light-shielded container and stirred to obtain a varnish containing a photosensitive resin composition.

[0296] <Examples 2 to 4 and Comparative Examples 1 to 2>

[0297] The copolymer A-1 was changed to copolymers A-2 to A-4, A-9, and A-10 as shown in Table 2, respectively. Except for this, a varnish was obtained in the same manner as in Example 1.

[0298] <Solubility Evaluation>

[0299] The varnishes obtained in the above Examples and Comparative Examples were visually observed, and the solubility was evaluated based on the following evaluation criteria. The evaluation results are shown in Table 2.

[0300] In addition, the solvent was changed to 4-methyl-2-pentanone (MIBK), and the same solubility evaluation was performed. The results are shown in Table 2.

[0301] (Evaluation Criteria)

[0302] 〇: There is no dissolution residue (precipitate), and the turbidity of the varnish is not seen.

[0303] △: There is no dissolution residue, but the turbidity of the varnish is visible.

[0304] ×: There is dissolution residue.

[0305] <Dissolution rate evaluation>

[0306] Prepare the varnishes obtained in the above examples and the varnishes obtained in Comparative Examples 1-2 in which PGMEA is changed to γ-butyrolactone.

[0307] Coat the varnish on a silicon substrate with a film thickness of about 2 μm using a spin coater.

[0308] Next, dry at 110 °C for 3 minutes using a hot plate to obtain a dry coating film. For the coating film, use a high-pressure mercury lamp to irradiate half of the dry coating film with 200 mJ / cm 2 of i-rays. After exposure, immerse it in a 2.38% aqueous solution of tetramethylammonium hydroxide (TMAH), measure the dissolution time, calculate the dissolution rate using the following formula, and evaluate the dissolution rates of the exposed part and the unexposed part based on the following evaluation criteria. The evaluation results are shown in Table 2.

[0309] In addition, calculate the dissolution contrast (dissolution rate of the exposed part / dissolution rate of the unexposed part) from the obtained dissolution rates of the exposed part and the unexposed part, and evaluate it based on the following evaluation criteria. The evaluation results are shown in Table 2.

[0310] Dissolution rate = Initial film thickness (nm) / Dissolution time (seconds)

[0311] (Evaluation criteria for dissolution rate of exposed part)

[0312] ◎: The dissolution rate is 500 nm / s or more and 1000 nm / s or less

[0313] ○: The dissolution rate is 200 nm / s or more and less than 500 nm / s

[0314] ×: The dissolution rate is less than 200 nm / s or exceeds 1000 nm / s

[0315] (Evaluation criteria for dissolution rate of unexposed part)

[0316] ◎: The dissolution rate is less than 5 nm / s

[0317] ○: The dissolution rate is 5 nm / s or more and less than 20 nm / s

[0318] ×: The dissolution rate is 20 nm / s or more

[0319] (Evaluation criteria for dissolution contrast)

[0320] ◎: The dissolution contrast is 200 or more

[0321] ○: The dissolution contrast ratio is 100 or more and less than 200

[0322] ×: The dissolution contrast ratio is less than 100

[0323] <Resolution evaluation>

[0324] Similar to the above dissolution rate evaluation, prepare the varnish obtained in the above examples and the varnishes obtained in Comparative Examples 1 to 2 in which PGMEA is changed to γ-butyrolactone.

[0325] Coat this varnish on a silicon substrate with a spin coater to a film thickness of about 2 μm.

[0326] Next, dry it on a hot plate at 110 °C for 3 minutes to obtain a dried coating film. For the coating film, irradiate it with diffused light of 200 mJ / cm 2 through a mask engraved with a pattern using a high-pressure mercury lamp. After exposure, develop it in a 2.38% aqueous solution of tetramethylammonium hydroxide (TMAH) for 60 seconds, and rinse with water to obtain a positive pattern film.

[0327] Change the L / S (line / space) of the pattern engraved on the mask from 1 μm / 1 μm to 30 μm / 30 μm in sequence (where L = S, and L and S are integers), and find the minimum L / S of the positive pattern film that can be formed and can pattern the exposed part without scum (development residue) observed by an electron microscope (SEM "JSM-6010"), and evaluate it based on the following evaluation criteria. The evaluation results are shown in Table 2.

[0328] (Evaluation criteria)

[0329] ◎: When the L / S of the pattern is 2 μm / 2 μm, a positive pattern film that can pattern the exposed part without scum (development residue) can also be formed.

[0330] ○: When the L / S of the pattern is 2 μm / 2 μm, a positive pattern film that can pattern the exposed part without scum (development residue) cannot be formed, but when the L / S of the pattern is 3 μm / 3 μm, it can.

[0331] △: When the L / S of the pattern is 3 μm / 3 μm, a positive pattern film that can pattern the exposed part without scum (development residue) cannot be formed, but when the L / S of the pattern is 5 μm / 5 μm, it can.

[0332] ×: When the L / S of the pattern is 5 μm / 5 μm, a positive pattern film that can pattern the exposed part without scum (development residue) cannot be formed.

[0333] <Storage stability evaluation>

[0334] Prepare the varnishes obtained in the above examples and the varnishes obtained in Comparative Examples 1-2 in which PGMEA is changed to γ-butyrolactone.

[0335] Measure the viscosities of these varnishes using a cone-plate viscometer (manufactured by Toki Sangyo Co., Ltd., TPE-100, rotation speed 50 rpm, 25 °C).

[0336] Next, keep the varnish in a constant temperature room at 4 °C for 7 days. Similarly, measure the viscosity after 7 days, calculate the viscosity change rate, and evaluate based on the following evaluation criteria. The evaluation results are shown in Table 2.

[0337] ◎: Viscosity change rate is less than 5%

[0338] ○: Viscosity change rate is 5% or more and less than 10%

[0339] ×: Viscosity change rate is 10% or more and less than 15%

[0340] [Table 2]

[0341]

[0342] <Examples 5-8>

[0343] Change copolymer A-1 to copolymers A-5 - A-8 as shown in Table 3. Otherwise, obtain the varnishes in the same manner as in Example 1.

[0344] In Examples A-5 - A-8, perform solubility evaluation, dissolution rate evaluation, and resolution evaluation in the same manner as above. In addition, measure the glass transition temperature (Tg) as follows. The evaluation results are shown in Table 3.

[0345] <Measurement of glass transition temperature (Tg)>

[0346] Similar to the above dissolution rate evaluation, prepare the varnishes obtained in the above examples and the varnishes obtained in Comparative Examples 1-2 in which PGMEA is changed to γ-butyrolactone.

[0347] Coat the varnish on a silicon substrate using a spin coater. Then, dry it on a hot plate at 110 °C for 3 minutes. After that, in an inert oven (CLH-21CD-S manufactured by Koyo Thermo System Co., Ltd.), heat it at 110 °C for 10 minutes in a nitrogen atmosphere, then hold it at 150 °C for 30 minutes, and heat it at 320 °C for 60 minutes to obtain a cured film with a film thickness of about 10 μm. Peel the obtained cured film from the substrate and measure Tg using a DSC from TA Instruments.

[0348] [Table 3]

[0349]

[0350] It is clearly understood from the evaluation results shown in Tables 1 to 3 that the photosensitive resin composition of the present invention has excellent dissolution rate and dissolution contrast in the exposed part and has high resolution. In addition, it is understood that the photosensitive resin composition of the present invention has high storage stability.

[0351] In addition, it is understood that the polyimide precursor used in the photosensitive resin composition of the present invention has high solubility in low-boiling solvents such as PGMEA and 4-methyl-2-pentanone.

[0352] Furthermore, it is understood that the cured product formed from the photosensitive resin composition has a high Tg and excellent heat resistance.

Claims

1. A photosensitive resin composition, comprising: (A) a polyimide precursor which is a reaction product of a diamine compound and a dicarboxylic acid, and (B) a photosensitizer, The diamine compound includes: At least one diamine compound selected from the following general formula (1) and (2): In the formula, A is selected from a single bond, O and a divalent organic group, B is a fluoroalcohol group, R is a substituted or unsubstituted alkyl or aryl group, n1 and n2 are each independently an integer from 0 to 4, and n1 + n2 is 1 or more, n3 and n4 are each independently an integer from 0 to 3, n5 is an integer from 1 to 4, n6 is an integer from 0 to 3; and At least one diamine compound selected from the following general formula (3) and (4): In the formula, A is selected from a single bond, O and a divalent organic group, R is a substituted or unsubstituted alkyl or aryl group, n7 and n8 are each independently an integer from 0 to 4, and n7 + n8 is 1 or more, n9 and n10 are each independently an integer from 0 to 3, n11 is an integer from 1 to 4, n12 is an integer from 0 to 3; The dicarboxylic acid includes at least one selected from carboxylic anhydrides and dicarboxylic acid chlorides, The composition ratio of the diamine compound in the polyimide precursor is as follows: the diamine compounds represented by the general formula (1) and (2) are 5 to 40 mol%, the diamine compounds represented by the general formula (3) and (4) are 15 to 35 mol%, and the composition ratio of the dicarboxylic acid is as follows: the dicarboxylic acid chloride is 10 to 50 mol%, and the carboxylic anhydride is 0 to 40 mol%.

2. The photosensitive resin composition according to claim 1, wherein, The fluorine concentration in the (A) polyimide precursor is 20 to 200 g / mol.

3. The photosensitive resin composition according to claim 1, wherein, The carboxyl concentration in the (A) polyimide precursor is 300 to 800 g / mol.

4. The photosensitive resin composition according to claim 1, wherein, The hydroxyl concentration in the (A) polyimide precursor is 200 to 600 g / mol.

5. The photosensitive resin composition according to any one of claims 1 to 4, wherein, In the general formula (1) and (2), the carbon number of the fluoroalcohol group represented by B is each independently 1 to 10, and the fluorine number is each independently 1 to 10.

6. The photosensitive resin composition according to any one of claims 1 to 4, further comprising (C) an adhesive.

7. The photosensitive resin composition according to any one of claims 1 to 4, wherein The (B) photosensitizer is a diazonaphthoquinone compound.

8. A dry film, comprising: a film; and a resin layer provided on the film and formed from the photosensitive resin composition according to any one of claims 1 to 7.

9. A cured product, which is formed from the photosensitive resin composition according to any one of claims 1 to 7, or is formed from the resin layer of a dry film having a resin layer formed from the photosensitive resin composition.

10. An electronic component, at least comprising the cured product according to claim 9.

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