JP7230383B2 - Photosensitive resin composition, photosensitive film, device, and method for forming resist pattern - Google Patents

Description

The present invention relates to a photosensitive resin composition, a photosensitive film, a device, and a method for forming a resist pattern.

In the manufacture of semiconductor devices or printed wiring boards, for example, negative photosensitive resin compositions are used to form fine patterns. In this method, a photosensitive layer is formed on a base material (a chip in the case of a semiconductor element, a substrate in the case of a printed wiring board) by coating a photosensitive resin composition or the like, and actinic rays are irradiated through a predetermined pattern. to cure the exposed areas. Furthermore, a resist pattern, which is a cured film of the photosensitive resin composition, is formed on the substrate by selectively removing the unexposed portions using a developer. Therefore, the photosensitive resin composition is required to have high sensitivity to actinic rays, to be able to form a fine pattern (resolution), and the like. Therefore, a photosensitive resin composition containing a novolak resin soluble in an alkaline aqueous solution, an epoxy resin and a photoacid generator, a photosensitive resin composition containing an alkali-soluble epoxy compound having a carboxyl group and a photocationic polymerization initiator, etc. has been proposed (see Patent Documents 1 and 2, for example).

Insulation reliability such as heat resistance, electrical properties, and mechanical properties is required for surface protective films and interlayer insulating films used in semiconductor devices. Accordingly, a photosensitive resin composition has been proposed that further contains a crosslinkable monomer in addition to the above photosensitive resin composition (see, for example, Patent Document 3).

On the other hand, in recent years, as the performance of electronic devices has improved, the degree of integration and reliability of semiconductor devices has been increasing year by year. 2. Description of the Related Art As semiconductor devices become highly integrated, formation of finer patterns and thinning of entire semiconductor devices are required. However, when the overall thickness of the semiconductor element is reduced, warping due to the difference in thermal expansion coefficient between the chip and the surface protective film or interlayer insulating film becomes a serious problem. It is strongly required to have a coefficient of thermal expansion close to the coefficient of thermal expansion (3×10 ⁻⁶ /° C.), that is, to lower the coefficient of thermal expansion. Therefore, in order to achieve low thermal expansion of the photosensitive resin composition, for example, a photosensitive resin composition containing an inorganic filler has been proposed (see, for example, Patent Document 4).

JP-A-09-087366 WO2008/010521 JP-A-2003-215802 JP 2011-13622 A

By forming a thick interlayer insulating film, the insulation between wirings in the thickness direction of the layer is improved, and short-circuiting of the wirings can be prevented, so that the reliability of the insulation between wirings is improved. Moreover, when a chip is mounted, since the semiconductor element has a thick interlayer insulating film, the stress applied to the pads of the solder bumps can be alleviated, so connection failures are less likely to occur during mounting. Therefore, from the viewpoint of insulation reliability and productivity when mounting a chip, it is also required to form a cured film of a photosensitive resin composition exceeding 20 μm. However, in conventional photosensitive resin compositions, when the thickness of the photosensitive layer is increased, good resolution may not be obtained or sufficient adhesion may not be obtained.

In addition, as the wiring pitch becomes narrower, the photosensitive resin composition is strongly required to improve the HAST (Highly Accelerated Temperature and Humidity Stress Test) resistance of the cured product. However, conventional photosensitive resin compositions have room for improvement in HAST resistance. In particular, the importance of insulation reliability between fine wirings is increasing, and compared to conventional tests in which a voltage is applied at 85 ° C. and 60% RH, or at 85 ° C. and 85% RH, 130 ° C. , and 85% RH, the test temperature is high, and resistance in the HAST test, which is a severe condition, is required.

The present invention solves the problems associated with the conventional techniques as described above, and provides a photosensitive resin composition capable of forming a resist pattern having excellent resolution and HAST resistance even with a photosensitive layer having a thickness exceeding 20 μm. intended to provide

The photosensitive resin composition of the present invention comprises (A) a polyfunctional phenolic novolak type epoxy resin and (B) at least one onium salt selected from the group consisting of onium borate salts and onium gallate salts. Contains an acid generator.

The onium salt may contain at least one cation selected from the group consisting of iodonium and sulfonium. The onium borate salt may also contain an anion consisting of tetrakis(pentafluorophenyl)borate.

The photosensitive resin composition of the present invention contains (C) a compound having a methylol group or an alkoxyalkyl group, (D) a sensitizer, or (E) an aliphatic or alicyclic epoxy compound having two or more oxirane rings. It may be contained further.

The photosensitive film of the present invention comprises a support and a photosensitive layer formed from the above photosensitive resin composition provided on the support.

A device according to the present invention comprises a cured product of the photosensitive resin composition.

A first embodiment of the method for forming a resist pattern of the present invention comprises a step of applying the photosensitive resin composition onto a substrate and drying the applied photosensitive resin composition to form a photosensitive layer; After exposing the layer in a predetermined pattern, the method includes a step of heat-treating, a step of developing the heat-treated photosensitive layer to obtain a resin pattern, and a step of heat-treating the resin pattern.

A second embodiment of the method for forming a resist pattern of the present invention comprises the steps of disposing the photosensitive layer of the photosensitive film on a substrate, exposing the photosensitive layer to a predetermined pattern and then heat-treating the photosensitive layer, and heat-treating the photosensitive layer. It comprises a step of developing the photosensitive layer to obtain a resin pattern, and a step of heat-treating the resin pattern.

According to the photosensitive resin composition of the present invention, it is possible to form a resist pattern excellent in resolution and HAST resistance even with a photosensitive layer having a thickness exceeding 20 μm.

An embodiment of the present invention will be specifically described below, but the present invention is not limited to this.

In this specification, the terms "layer" and "film" refer to a structure having a shape formed over the entire surface and a structure having a shape formed partially when observed as a plan view. subsumed. The term "process" is included in the term not only as an independent process, but also as long as the intended purpose of the process is achieved, even if the process cannot be clearly distinguished from other processes. A numerical range indicated using "-" indicates a range including the numerical values before and after "-" as the minimum and maximum values, respectively.

[Photosensitive resin composition]
The photosensitive resin composition of the present embodiment comprises (A) a polyfunctional bisphenol novolac type epoxy resin and (B) a photosensitive resin composition containing at least one onium salt selected from the group consisting of onium borate salts and onium gallate salts. and a volatile acid generator.

((A) polyfunctional phenolic novolac type epoxy resin)
The polyfunctional phenolic novolac type epoxy resin that is the component (A) is not particularly limited as long as it is a phenolic novolac type epoxy resin having two or more epoxy groups. From the viewpoint of increasing the thickness of the photosensitive layer, the component (A) is preferably an epoxy resin having four or more epoxy groups, and more preferably an epoxy resin having five or more epoxy groups.

Component (A) includes, for example, polyfunctional ortho-cresol novolac type epoxy resins, polyfunctional triphenyl novolac type epoxy resins, polyfunctional bisphenol A novolak type epoxy resins, and bisphenol F novolac type epoxy resins. Among them, a polyfunctional bisphenol A novolak type epoxy resin or a bisphenol F novolak type epoxy resin is preferably used. Component (A) is commercially available, for example, under the trade name of "Epicort 157S70" from Mitsubishi Chemical Corporation and under the trade name of "Epiclon N-865" from DIC Corporation.

As the polyfunctional bisphenol novolak type epoxy resin, an epoxy resin represented by the following formula (a1) may be used.

In formula (a1), R ¹¹ to R ¹⁶ each represent a hydrogen atom or a methyl group, and m is an integer of 0-5.

The epoxy resin represented by formula (a1) may be a polymer of a bisphenol A/F type epoxy resin or a bisphenol A/F novolac type epoxy resin and an epoxy group-containing component.

The softening point of component (A) is not particularly limited as long as it is solid at room temperature, but it is usually preferably about 50°C to about 100°C, more preferably about 60°C to about 80°C.

The content of component (A) is preferably 40 to 99.9% by mass, based on the total amount of all solids contained in the photosensitive resin composition, and is 45 to 99.9% by mass. is more preferable, and 50 to 99.4% by mass is even more preferable. As a result, when a photosensitive layer is formed using the photosensitive resin composition, a thick resist layer having high sensitivity and suitable hardness can be easily obtained.

((B) Photosensitive acid generator)
The photosensitive acid generator as component (B) is a compound that generates an acid upon exposure to actinic rays or the like. Due to the catalytic effect of the acid generated from the photosensitive acid generator, cationic polymerization proceeds between epoxy groups in component (A). Patterns can be formed.

The component (B) contains at least one onium salt selected from the group consisting of onium borate salts and onium gallate salts. The onium salt preferably contains at least one cation selected from the group consisting of iodonium and sulfonium. (B) component can be used individually by 1 type or in mixture of 2 or more types.

The onium borate salt may contain an anion having a tetraphenylborate skeleton. The hydrogen atom of the phenyl group in the tetraphenylborate skeleton is a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, a nitro group, a hydroxy group, an alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms. , an alkylcarbonyl group having 2 to 12 carbon atoms, and an alkoxycarbonyl group having 2 to 12 carbon atoms. There may be or may be different.

The anion having a tetraphenylborate skeleton may be tetrakis(pentafluorophenyl)borate, which is more excellent in HAST resistance and sensitivity.

The onium borate salt may contain a cation having an alkylsulfonate skeleton. The hydrogen atom of the alkylsulfonate skeleton is at least one selected from the group consisting of a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, a nitro group, a hydroxy group, an alkoxy group, an alkylcarbonyl group, and an alkoxycarbonyl group. may be substituted with, and when there are a plurality of substituents, they may be the same or different. The hydrogen atom of the phenyl group of the phenylsulfonate skeleton is a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, a nitro group, a hydroxy group, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, may be substituted with at least one selected from the group consisting of an alkylcarbonyl group having 2 to 12 carbon atoms and an alkoxycarbonyl group having 2 to 12 carbon atoms; may be different.

Cations having an alkylsulfonate skeleton include, for example, triphenylsulfonium, 4-t-butylphenyl-diphenylsulfonium, diphenyl[4-(phenylthio)phenyl]sulfonium, [4-(4-biphenylylthio)phenyl]-4 -biphenylylphenylsulfonium, (2-methyl)phenyl[4-(4-biphenylylthio)phenyl]4-biphenylylsulfonium, [4-(4-biphenylylthio)-3-methylphenyl]4-biphenylyl Phenylsulfonium, (2-methyl)phenyl[4-(4-biphenylylthio)-3-methylphenyl]4-biphenylylsulfonium, (2-methoxy)phenyl[4-(4-biphenylylthio)-3- methoxyphenyl]4-biphenylylsulfonium, (2-ethoxy)phenyl[4-(4-biphenylylthio)-3-ethoxyphenyl]4-biphenylylsulfonium, (2-butoxy)phenyl[4-(4-biphenyl lylthio)-3-butoxyphenyl]4-biphenylylsulfonium, tris[4-(4-acetylphenylsulfanyl)phenyl]sulfonium, tris[4-(4-acetyl-3-methylphenylthio)phenyl]sulfonium, tris and triarylsulfonium such as [4-(4-acetyl-3-ethylphenylthio)phenyl]sulfonium and tris[4-(4-acetyl-3-butylphenylthio)phenyl]sulfonium.

Specific examples of onium borate salts containing an anion having a tetraphenylborate skeleton and a cation having an alkylsulfonate skeleton include triphenylsulfonium tetrakis(pentafluorophenyl)borate, triphenylsulfonium tetraphenylborate, and 4-t-butyl. phenyl-diphenylsulfonium tetrakis(pentafluorophenyl)borate, 4-t-butylphenyl-diphenylsulfonium tetraphenylborate, diphenyl[4-(phenylthio)phenyl]sulfoniumtetrakis(pentafluorophenyl)borate, diphenyl[4-(phenylthio) Phenyl]sulfonium tetraphenylborate, [4-(4-biphenylylthio)phenyl]-4-biphenylylphenylsulfonium tetrakis(pentafluorophenyl)borate, [4-(4-biphenylylthio)phenyl]-4-biphenyl Lylphenylsulfonium tetraphenylborate, (2-methyl)phenyl[4-(4-biphenylylthio)phenyl]4-biphenylylsulfonium tetrakis(pentafluorophenyl)borate, (2-methyl)phenyl[4-(4- biphenylylthio)phenyl]4-biphenylylsulfonium tetraphenylborate, [4-(4-biphenylylthio)-3-methylphenyl]4-biphenylylphenylsulfonium tetrakis(pentafluorophenyl)borate, [4-(4 -biphenylylthio)-3-methylphenyl]4-biphenylylphenylsulfonium tetraphenylborate, (2-methyl)phenyl [4-(4-biphenylylthio)-3-methylphenyl]4-biphenylylsulfonium tetrakis ( pentafluorophenyl)borate, (2-methyl)phenyl[4-(4-biphenylylthio)-3-methylphenyl]4-biphenylylsulfonium tetraphenylborate, (2-methoxy)phenyl[4-(4-biphenyl lylthio)-3-methoxyphenyl]4-biphenylylsulfonium tetrakis(pentafluorophenyl)borate, (2-methoxy)phenyl[4-(4-biphenylylthio)-3-methoxyphenyl]4-biphenylylsulfonium tetra Phenylborate, (2-ethoxy)phenyl[4-(4-biphenylylthio)-3-ethoxyphenyl]4-biphenylylsulfonium tetrakis(pentafluorophenyl) phenyl)borate, (2-ethoxy)phenyl[4-(4-biphenylylthio)-3-ethoxyphenyl]4-biphenylylsulfonium tetraphenylborate, (2-butoxy)phenyl[4-(4-biphenylylthio )-3-butoxyphenyl]4-biphenylylsulfonium tetrakis(pentafluorophenyl)borate, (2-butoxy)phenyl[4-(4-biphenylylthio)-3-butoxyphenyl]4-biphenylylsulfonium tetraphenylborate , tris[4-(4-acetylphenylsulfanyl)phenyl]sulfonium tetrakis(pentafluorophenyl)borate, tris[4-(4-acetylphenylsulfanyl)phenyl]sulfonium methanesulfonate, tris[4-(4-acetylphenylsulfanyl) ) phenyl]sulfonium butanesulfonate, tris[4-(4-acetylphenylsulfanyl)phenyl]sulfonium octanesulfonate, tris[4-(4-acetylphenylsulfanyl)phenyl]sulfonium tetraphenylborate, tris[4-(4-acetyl phenylsulfanyl)phenyl]sulfonium p-toluenesulfonate, tris[4-(4-acetylphenylsulfanyl)phenyl]sulfonium 10-camphorsulfonate, tris[4-(4-acetyl-3-methylphenylthio)phenyl]sulfonium trifluoromethane Sulfonate, Tris[4-(4-acetyl-3-methylphenylthio)phenyl]sulfonium nonafluorobutanesulfonate, Tris[4-(4-acetyl-3-methylphenylthio)phenyl]sulfonium heptadecafluorooctane sulfonate, Tris [4-(4-acetyl-3-methylphenylthio)phenyl]sulfonium tetrakis(pentafluorophenyl)borate, tris[4-(4-acetyl-3-methylphenylthio)phenyl]sulfonium methanesulfonate, tris[4- (4-acetyl-3-methylphenylthio)phenyl]sulfonium butanesulfonate, tris[4-(4-acetyl-3-methylphenylthio)phenyl]sulfonium octanesulfonate, tris[4-(4-acetyl-3-methyl) phenylthio)phenyl]sulfonium tetraphenylborate, tris[4-(4-acetyl-3-methylphenylthio)phenyl]sulfonium Sulfonium p-toluenesulfonate, tris[4-(4-acetyl-3-methylphenylthio)phenyl]sulfonium 10-camphorsulfonate, tris[4-(4-acetyl-3-ethylphenylthio)phenyl]sulfonium trifluoromethanesulfonate , tris[4-(4-acetyl-3-ethylphenylthio)phenyl]sulfonium nonafluorobutanesulfonate, tris[4-(4-acetyl-3-ethylphenylthio)phenyl]sulfonium heptadecafluorooctane sulfonate, tris[ 4-(4-acetyl-3-ethylphenylthio)phenyl]sulfonium tetrakis(pentafluorophenyl)borate, tris[4-(4-acetyl-3-ethylphenylthio)phenyl]sulfonium methanesulfonate, tris[4-( 4-acetyl-3-ethylphenylthio)phenyl]sulfonium butanesulfonate, tris[4-(4-acetyl-3-ethylphenylthio)phenyl]sulfonium octanesulfonate, tris[4-(4-acetyl-3-ethylphenyl thio)phenyl]sulfonium tetraphenylborate, tris[4-(4-acetyl-3-ethylphenylthio)phenyl]sulfonium p-toluenesulfonate, tris[4-(4-acetyl-3-ethylphenylthio)phenyl]sulfonium 10-camphorsulfonate, tris[4-(4-acetyl-3-butylphenylthio)phenyl]sulfonium trifluoromethanesulfonate, tris[4-(4-acetyl-3-butylphenylthio)phenyl]sulfonium nonafluorobutanesulfonate, tris[4-(4-acetyl-3-butylphenylthio)phenyl]sulfonium heptadecafluorooctane sulfonate and tris[4-(4-acetyl-3-butylphenylthio)phenyl]sulfonium tetrakis(pentafluorophenyl)borate mentioned.

The onium gallate salt is not particularly limited as long as it has a cation containing a gallium atom. As the onium gallate salt, for example, the onium gallate salt described in JP-A-2017-48325 may be used.

The onium gallate salt may be an onium salt represented by the following general formula (11).

R ¹ to R ⁴ in formula (11) each independently represent an alkyl group having 1 to 18 carbon atoms, an aryl group, or a group having a heterocyclic ring, and at least one of R ¹ to R ⁴ is an aryl group is. The aryl group may have a substituent. The number of carbon atoms in the aryl group (excluding the number of carbon atoms in the substituent) is 6-14.

The alkyl group having 1 to 18 carbon atoms for R ¹ to R ⁴ includes methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-octyl, n-decyl, n-dodecyl, n-tetradecyl, Linear alkyl groups such as n-hexadecyl and n-octadecyl; isopropyl, isobutyl, sec-butyl, tert-butyl, isopentyl, neopentyl, tert-pentyl, isohexyl, 2-ethylhexyl, 1,1,3,3-tetramethyl branched alkyl groups such as butyl; cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl and cyclohexyl; and bridged cyclic alkyl groups such as norbornyl, adamantyl and pinanyl. From the viewpoint of catalytic activity in a cationic polymerization reaction, an alkyl group substituted with a halogen atom, a nitro group or a cyano group is preferred, and an alkyl group substituted with a fluorine atom is more preferred.

The aryl group having 6 to 14 carbon atoms includes, for example, monocyclic aryl groups such as phenyl; and condensed polycyclic aryl groups such as naphthyl, anthracenyl, phenanthrenyl, anthraquinolyl, fluorenyl and naphthoquinolyl. Heterocyclic groups include monocyclic heterocyclic groups such as thienyl, furanyl, pyranyl, pyrrolyl, oxazolyl, thiazolyl, pyridyl, pyrimidyl and pyrazinyl; and indolyl, benzofuranyl, isobenzofuranyl, benzothienyl and isobenzothienyl. , quinolyl, isoquinolyl, quinoxalinyl, quinazolinyl, carbazolyl, acridinyl, phenothiazinyl, phenazinyl, xanthenyl, thianthrenyl, phenoxazinyl, phenoxathiinyl, chromanyl, isochromanyl, coumarinyl, dibenzothienyl, xanthonyl, thioxanthonyl, dibenzofuranyl, and other condensed polycyclic rings heterocyclic groups. Some or all of the hydrogen atoms in the above groups are alkyl groups having 1 to 18 carbon atoms, alkyl groups having 1 to 8 carbon atoms and halogen atoms, alkenyl groups having 2 to 18 carbon atoms, and alkynyl group, aryl group having 6 to 14 carbon atoms, nitro group, hydroxyl group, cyano group, alkoxy group having 1 to 8 carbon atoms, aryloxy group having 6 to 14 carbon atoms, acyl group having 1 to 8 carbon atoms, carbon number It may be substituted with a group such as an acyloxy group having 1 to 8 carbon atoms, an alkylthio group having 1 to 8 carbon atoms, an arylthio group having 6 to 14 carbon atoms, an amino group, or the like.

Examples of alkenyl groups having 2 to 18 carbon atoms include vinyl, allyl, 1-propenyl, 2-propenyl, 1-butenyl, 2-butenyl, 3-butenyl, 1-methyl-1-propenyl, 1-methyl-2 -propenyl, 2-methyl-1-propenyl, 2-methyl-2-propenyl, 2-cyclohexenyl, 3-cyclohexenyl, styryl and cinnamyl.

Examples of alkynyl groups having 2 to 18 carbon atoms include ethynyl, 1-propynyl, 2-propynyl, 1-butynyl, 2-butynyl, 3-butynyl, 1-methyl-2-propynyl, 1,1-dimethyl-2 -propynyl, 1-pentynyl, 2-pentynyl, 3-pentynyl, 4-pentynyl, 1-methyl-2-butynyl, 3-methyl-1-butynyl, 1-decynyl, 2-decynyl, 8-decynyl, 1- Dodecynyl, 2-dodecynyl, 10-dodecynyl and phenylethynyl.

Examples of alkyl groups having 1 to 8 carbon atoms and having a halogen atom include trifluoromethyl, trichloromethyl, pentafluoroethyl, 2,2,2-trichloroethyl, 2,2,2-trifluoroethyl, 1,1 -difluoroethyl, heptafluoro-n-propyl, 1,1-difluoro-n-propyl, 3,3,3-trifluoro-n-propyl, nonafluoro-n-butyl, 3,3,4,4,4- Pentafluoro-n-butyl, perfluoro-n-pentyl, perfluoro-n-octyl, hexafluoroisopropyl, hexachloroisopropyl, hexafluoroisobutyl, nonafluoro-tert-butyl, pentafluorocyclopropyl, nonafluorocyclobutyl, perfluoro Cyclopentyl and perfluorocyclohexyl and perfluoroadamantyl are included.

Alkoxy groups include, for example, methoxy, ethoxy, n-propoxy, iso-propoxy, n-butoxy, sec-butoxy, tert-butoxy, n-pentoxy, iso-pentoxy, neo-pentoxy and 2-methylbutoxy. . Aryloxy groups include, for example, phenoxy and naphthoxy. Acyl groups include, for example, acetyl, propanoyl, butanoyl, pivaloyl and benzoyl. Acyloxy groups include, for example, acetoxy, butanoyloxy and benzoyloxy. Alkylthio groups include, for example, methylthio, ethylthio, butylthio, hexylthio and cyclohexylthio. Arylthio groups include, for example, phenylthio and naphthylthio. Amino groups include methylamino, ethylamino, propylamino, dimethylamino, diethylamino, methylethylamino, dipropylamino, dipropylamino and piperidino. Halogen atoms include fluorine, chlorine, bromine and iodine atoms.

Among these substituents, from the viewpoint of catalytic activity in a cationic polymerization reaction, an alkyl group having 1 to 8 carbon atoms having a halogen atom, a halogen atom, a nitro group and a cyano group are preferable, and an alkyl having 1 to 8 carbon atoms having a fluorine atom. Groups and fluorine atoms are more preferred.

The onium gallate salt may contain any one of gallate anions represented by formulas (A-1) to (A-5) below.

A gallate anion can be synthesized by a known method, and can be obtained, for example, by reacting gallium (III) chloride with an organometallic compound such as an organolithium compound or an organomagnesium compound (Tetrahedron 58 (2002) 5267- 5273).

E in formula (11) is group 15 elements in IUPAC notation (nitrogen, phosphorus, arsenic, antimony, bismuth), group 16 elements (oxygen, sulfur, selenium, tellurium, polonium) and group 17 elements (fluorine , chlorine, bromine, iodine, astatine), and n is an integer of 1-3. ^R5 represents an organic group, and the number of ^R5 is n+1. (n+1) R ⁵ may be the same or different, two or more R ⁵ may be directly bonded, -O-, -S-, -SO-, -SO ₂ A ring structure containing E may be formed via -, -NH-, -CO-, -COO-, -CONH-, an alkylene group or a phenylene group.

Examples of R ⁵ include an aryl group having 6 to 14 carbon atoms, an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms and an alkynyl group having 2 to 18 carbon atoms. The aryl group is an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, an alkynyl group having 2 to 18 carbon atoms, an aryl group having 6 to 14 carbon atoms, a nitro group, a hydroxyl group, a cyano group, an alkoxy group. , an aryloxy group, an acyl group, an acyloxy group, an alkylthio group, an arylthio group, an amino group or a halogen atom.

E combines with ^R5 to form an onium ion (E ⁺ ). E is preferably oxygen (O), nitrogen (N), phosphorus (P), sulfur (S) or iodine (I). Corresponding cations include, for example, oxonium, ammonium, phosphonium, sulfonium and iodonium. Preferred cations are ammonium, phosphonium, sulfonium and iodonium from the viewpoint of stability and ease of handling, and more preferred are sulfonium and iodonium from the viewpoint of excellent cationic polymerizability and cross-linking reactivity.

Specific examples of oxonium include oxonium such as trimethyloxonium, diethylmethyloxonium, triethyloxonium, tetramethylenemethyloxonium; pyririnium such as -tert-butylpyrilinium and 2,6-diphenylpyrilinium; chromenium and isochromenium such as 2,4-dimethylchromenium and 1,3-dimethylisochromenium;

Specific examples of ammonium include tetraalkylammonium such as tetramethylammonium, ethyltrimethylammonium, diethyldimethylammonium, triethylmethylammonium and tetraethylammonium; N,N-dimethylpyrrolidinium and N-ethyl-N-methylpyrrolidinium , N,N-diethylpyrrolidinium; N,N'-dimethylimidazolinium, N,N'-diethylimidazolinium, N-ethyl-N'-methylimidazolinium, 1,3,4 - imidazolinium such as trimethylimidazolinium, 1,2,3,4-tetramethylimidazolinium; tetrahydropyrimidinium such as N,N'-dimethyltetrahydropyrimidinium; N,N'-dimethylmorphol morpholinium such as N,N'-diethylpiperidinium; piperidinium such as N,N'-diethylpiperidinium; pyridinium such as N-methylpyridinium, N-benzylpyridinium, N-phenacylpyridinium; imidazolium such as N,N'-dimethylimidazolium quinolium such as N-methylquinolium, N-benzylquinolium and N-phenacylquinolium; isoquinolium such as N-methylisoquinolium; thiazonium such as benzylbenzothiazonium and phenacylbenzothiazonium; benzyl Acridium such as acridium and phenacylacridium.

Specific examples of phosphonium include tetraphenylphosphonium, tetra-p-tolylphosphonium, tetrakis(2-methoxyphenyl)phosphonium, tetrakis(3-methoxyphenyl)phosphonium, tetraarylphosphonium such as tetrakis(4-methoxyphenyl)phosphonium; triarylphosphoniums such as triphenylbenzylphosphonium, triphenylphenacylphosphonium, triphenylmethylphosphonium, triphenylbutylphosphonium; Examples include tetraalkylphosphoniums such as tributylphenacylphosphonium.

Specific examples of sulfonium include triphenylsulfonium, tri-p-tolylsulfonium, tri-o-tolylsulfonium, tris(4-methoxyphenyl)sulfonium, 1-naphthyldiphenylsulfonium, 2-naphthyldiphenylsulfonium, tris(4- fluorophenyl)sulfonium, tri-1-naphthylsulfonium, tri-2-naphthylsulfonium, tris(4-hydroxyphenyl)sulfonium, 4-(phenylthio)phenyldiphenylsulfonium, 4-(p-tolylthio)phenyldi-p-tolylsulfonium , 4-(4-methoxyphenylthio)phenylbis(4-methoxyphenyl)sulfonium, 4-(phenylthio)phenylbis(4-fluorophenyl)sulfonium, 4-(phenylthio)phenylbis(4-methoxyphenyl)sulfonium, 4-(phenylthio)phenyldi-p-tolylsulfonium, [4-(4-biphenylylthio)phenyl]-4-biphenylylphenylsulfonium, [4-(2-thioxanthonylthio)phenyl]diphenylsulfonium, bis[ 4-(diphenylsulfonio)phenyl]sulfide, bis[4-{bis[4-(2-hydroxyethoxy)phenyl]sulfonio}phenyl]sulfide, bis{4-[bis(4-fluorophenyl)sulfonio]phenyl} sulfide, bis{4-[bis(4-methylphenyl)sulfonio]phenyl}sulfide, bis{4-[bis(4-methoxyphenyl)sulfonio]phenyl}sulfide, 4-(4-benzoyl-2-chlorophenylthio) Phenylbis(4-fluorophenyl)sulfonium, 4-(4-benzoyl-2-chlorophenylthio)phenyldiphenylsulfonium, 4-(4-benzoylphenylthio)phenylbis(4-fluorophenyl)sulfonium, 4-(4- benzoylphenylthio)phenyldiphenylsulfonium, 7-isopropyl-9-oxo-10-thia-9,10-dihydroanthracen-2-yldi-p-tolylsulfonium, 7-isopropyl-9-oxo-10-thia-9, 10-dihydroanthracen-2-yldiphenylsulfonium, 2-[(di-p-tolyl)sulfonio]thioxanthone, 2-[(diphenyl)sulfonio]thioxanthone, 4-(9-oxo-9H-thioxanthen-2-yl ) thiophenyl-9-o xo-9H-thioxanthen-2-yl phenylsulfonium, 4-[4-(4-tert-butylbenzoyl)phenylthio]phenyldi-p-tolylsulfonium, 4-[4-(4-tert-butylbenzoyl)phenylthio] phenyldiphenylsulfonium, 4-[4-(benzoylphenylthio)]phenyldi-p-tolylsulfonium, 4-[4-(benzoylphenylthio)]phenyldiphenylsulfonium, 5-(4-methoxyphenyl)thianthrenium, 5 - triarylsulfoniums such as phenylthianthrenium, 5-tolylthianthrenium, 5-(4-ethoxyphenyl)thiaanthrenium, 5-(2,4,6-trimethylphenyl)thiaanthrenium; diphenylphenacylsulfonium; , diphenyl 4-nitrophenacylsulfonium, diphenylbenzylsulfonium, diphenylmethylsulfonium, etc.; phenylmethylbenzylsulfonium, 4-hydroxyphenylmethylbenzylsulfonium, 4-methoxyphenylmethylbenzylsulfonium, 4-acetocarbonyloxyphenylmethylbenzyl sulfonium, 4-hydroxyphenyl(2-naphthylmethyl)methylsulfonium, 2-naphthylmethylbenzylsulfonium, 2-naphthylmethyl(1-ethoxycarbonyl)ethylsulfonium, phenylmethylphenacylsulfonium, 4-hydroxyphenylmethylphenacylsulfonium, Monoarylsulfonium such as 4-methoxyphenylmethylphenacylsulfonium, 4-acetocarbonyloxyphenylmethylphenacylsulfonium, 2-naphthylmethylphenacylsulfonium, 2-naphthyloctadecylphenacylsulfonium, 9-anthracenylmethylphenacylsulfonium trialkylsulfonium such as dimethylphenacylsulfonium, phenacyltetrahydrothiophenium, dimethylbenzylsulfonium, benzyltetrahydrothiophenium, octadecylmethylphenacylsulfonium;

Specific examples of iodonium include diphenyliodonium, di-p-tolyliodonium, bis(4-dodecylphenyl)iodonium, bis(4-methoxyphenyl)iodonium, (4-octyloxyphenyl)phenyliodonium, bis(4-decyloxy ) phenyliodonium, 4-(2-hydroxytetradecyloxy)phenylphenyliodonium, 4-isopropylphenyl(p-tolyl)iodonium and 4-isobutylphenyl(p-tolyl)iodonium.

The content of component (B) is from 0.1 to 0.1 per 100 parts by mass of component (A), from the viewpoint of further improving the sensitivity, resolution, pattern shape, etc. of the photosensitive resin composition of the present embodiment. 15 parts by mass is preferable, 0.3 to 10 parts by mass is more preferable, and 1 to 10 parts by mass is even more preferable. In this specification, 100 parts by mass of component (A) means that the solid content of component (A) is 100 parts by mass.

The component (B) may be dissolved in a solvent before use when preparing the photosensitive resin composition. As the solvent, a solvent exemplified as component (F) described below may be used.

((C) a compound having a methylol group or an alkoxyalkyl group)
The photosensitive resin composition of this embodiment may further contain a compound having a methylol group or an alkoxyalkyl group as the component (C). Component (C) is preferably a compound further having at least one selected from the group consisting of aromatic rings, heterocyclic rings and alicyclic rings. Here, the aromatic ring means an aromatic hydrocarbon group (eg, a hydrocarbon group having 6 to 10 carbon atoms), such as a benzene ring and a naphthalene ring. A heterocyclic ring means a cyclic group having at least one heteroatom such as a nitrogen atom, an oxygen atom, a sulfur atom (eg, a cyclic group having 3 to 10 carbon atoms), and examples thereof include a pyridine ring, an imidazole ring, A pyrrolidinone ring, an oxazolidinone ring, an imidazolidinone ring and a pyrimidinone ring are included. In addition, the alicyclic means a cyclic hydrocarbon group having no aromaticity (eg, a cyclic hydrocarbon group having 3 to 10 carbon atoms), such as a cyclopropane ring, a cyclobutane ring, a cyclopentane ring and A cyclohexane ring is mentioned. An alkoxyalkyl group means a group in which an alkyl group is bonded to an alkyl group through an oxygen atom. Also, the two alkyl groups may be different from each other, for example, alkyl groups having 1 to 10 carbon atoms.

By containing the component (C), when the photosensitive layer after the formation of the resin pattern is heated and cured, the component (C) reacts with the component (A) to form a bridge structure, and the resin pattern becomes fragile. It is possible to prevent quenching and deformation of the resin pattern, and improve heat resistance. Moreover, specifically, a compound further having a phenolic hydroxyl group or a compound further having a hydroxymethylamino group can be preferably used, and components (A) and (C) are not included.

By including the component (B) in the photosensitive resin composition, an acid is generated upon exposure to actinic rays or the like. The alkoxyalkyl groups in the component (C) or the alkoxyalkyl groups in the component (C) and the component (A) can be reacted with dealcoholization by the catalytic action of the generated acid. Moreover, the methylol groups in the component (C) or the methylol groups in the component (C) and the component (A) can be reacted with dealcoholization by the catalytic action of the generated acid.

The "compound further having a phenolic hydroxyl group" used as the component (C) has a methylol group or an alkoxyalkyl group, so that it reacts not only with the component (C) or the component (A), but also during development with an alkaline aqueous solution. It is possible to increase the dissolution rate of the unexposed portion of the , and improve the sensitivity. The molecular weight of the compound having a phenolic hydroxyl group is preferably 94 to 2000 in terms of weight average molecular weight (Mw) in consideration of improving the solubility in alkaline aqueous solution, photosensitivity, mechanical properties, etc. in a well-balanced manner. It is more preferably 108-2000, even more preferably 108-1500.

As the compound having a phenolic hydroxyl group, conventionally known compounds can be used. It is preferable because it is excellent in the balance of the effect of preventing melting.

In formula (1), Z represents a single bond or a divalent organic group, R ₂₄ and R ₂₅ each independently represent a hydrogen atom or a monovalent organic group, R ₂₆ and R ₂₇ each independently represent a monovalent wherein a and b each independently represent an integer of 1 to 3, and c and d each independently represent an integer of 0 to 3. Here, the monovalent organic group includes, for example, an alkyl group having 1 to 10 carbon atoms such as a methyl group, an ethyl group, and a propyl group; an alkenyl group having 2 to 10 carbon atoms such as a vinyl group. an aryl group having 6 to 30 carbon atoms such as a phenyl group; and a group in which some or all of the hydrogen atoms of these hydrocarbon groups are substituted with halogen atoms such as fluorine atoms.

The compound represented by general formula (1) is preferably a compound represented by general formula (2) below.

In formula (2), X ₁ represents a single bond or a divalent organic group, and R represents an alkyl group (eg, an alkyl group having 1 to 10 carbon atoms).

A compound represented by the following general formula (3) may be used as the compound having a phenolic hydroxyl group.

In formula (3), R represents an alkyl group (eg, an alkyl group having 1 to 10 carbon atoms).

Moreover, in the general formula (1), compounds in which Z is a single bond are biphenol (dihydroxybiphenyl) derivatives. In addition, the divalent organic group represented by Z includes an alkylene group having 1 to 10 carbon atoms such as a methylene group, an ethylene group and a propylene group; an alkylidene group having 2 to 10 carbon atoms such as an ethylidene group. A group; an arylene group having 6 to 30 carbon atoms such as a phenylene group; a group in which some or all of the hydrogen atoms of these hydrocarbon groups are substituted with a halogen atom such as a fluorine atom; a sulfonyl group; a carbonyl group; an ether bond ; sulfide bond; amide bond, and the like. Among these, Z is preferably a divalent organic group represented by the following general formula (4).

In formula (4), X ₂ is a single bond, an alkylene group (eg, an alkylene group having 1 to 10 carbon atoms), an alkylidene group (eg, an alkylidene group having 2 to 10 carbon atoms), hydrogen thereof It represents a group in which some or all of the atoms are substituted with halogen atoms, a sulfonyl group, a carbonyl group, an ether bond, a sulfide bond or an amide bond. R ₂₈ represents a hydrogen atom, a hydroxyl group, an alkyl group (eg, an alkyl group having 1-10 carbon atoms) or a haloalkyl group, and e represents an integer of 1-10. A plurality of R ₂₈ may be the same or different. Here, a haloalkyl group means an alkyl group substituted with a halogen atom.

Compounds having a hydroxymethylamino group include (poly)(N-hydroxymethyl)melamine, (poly)(N-hydroxymethyl)glycoluril, (poly)(N-hydroxymethyl)benzoguanamine, (poly)(N- hydroxymethyl)urea and the like. Nitrogen-containing compounds obtained by alkyl-etherifying all or part of the hydroxymethylamino groups of these compounds may also be used. Here, the alkyl group of the alkyl ether includes a methyl group, an ethyl group, a butyl group, or a mixture thereof, and may contain an oligomer component formed by partial self-condensation. Specific examples include hexakis(methoxymethyl)melamine, hexakis(butoxymethyl)melamine, tetrakis(methoxymethyl)glycoluril, tetrakis(butoxymethyl)glycoluril, and tetrakis(methoxymethyl)urea.

Specifically, the compound having a hydroxymethylamino group is preferably a compound represented by the following general formula (5) or a compound represented by the following general formula (6).

In formulas (5) and (6), each R independently represents an alkyl group (eg, an alkyl group having 1 to 10 carbon atoms).

The content of component (C) is preferably 5 to 60 parts by mass, more preferably 6 to 45 parts by mass, and 8 to 35 parts by mass with respect to 100 parts by mass of component (A). is more preferred. When the content of component (C) is 5 parts by mass or more, the chemical resistance and heat resistance tend to be improved. It tends to be easy to form a film.

((D) sensitizer)
The photosensitive resin composition of the present embodiment may further contain a sensitizer as component (D). By containing the component (D), the photosensitivity of the photosensitive resin composition can be improved. A naphthalene-based sensitizer or an anthracene-based sensitizer may be used as the component (D). Examples of anthracene-based sensitizers include 9,10-dibutoxyanthracene. Component (D) may be used singly or in combination of two or more.

The content of component (D) is preferably 0.01 to 1.5 parts by mass, more preferably 0.05 to 0.5 parts by mass, per 100 parts by mass of component (A). .

((E) Aliphatic or Alicyclic Epoxy Compound)
The photosensitive resin composition of the present embodiment may further contain an aliphatic or alicyclic epoxy compound having two or more oxirane rings as component (E). Component (E) is preferably a compound having two or more glycidyl ether groups, more preferably a compound having three or more glycidyl ether groups. Component (E) is preferably an epoxy compound having a weight average molecular weight of 1,000 or less. As used herein, the term "aliphatic or alicyclic epoxy compound" refers to a compound whose main skeleton is an aliphatic skeleton and/or an alicyclic skeleton and does not contain an aromatic ring or heterocyclic ring.

Examples of component (E) include ethylene glycol diglycidyl ether, diethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, Glycerin diglycidyl ether, pentaerythritol tetraglycidyl ether, trimethylolethane triglycidyl ether, trimethylolpropane triglycidyl ether, glycerol propoxylate triglycidyl ether, dicyclopentadiene dioxide, 1,2,5,6-diepoxycyclooctane , 1,4-cyclohexanedimethanol diglycidyl ether, diglycidyl 1,2-cyclohexanedicarboxylate, 3,4-epoxycyclohexylmethyl 3′,4′-epoxycyclohexanecarboxylate, bis(3,4-epoxycyclohexylmethyl) Adipate and cyclohexene oxide type epoxy resins are included.

Among the components (E), trimethylolethane triglycidyl ether or trimethylolpropane triglycidyl ether is preferable from the viewpoint of excellent resolution and film properties.

Component (E) includes, for example, Epolite 40E, Epolite 100E, Epolite 70P, Epolite 200P, Epolite 1500NP, Epolite 1600, Epolite 80MF, Epolite 100MF (these are trade names of Kyoeisha Chemical Co., Ltd.), and alkyl-type epoxy resin ZX-1542. (trade name of Nippon Steel & Sumikin Chemical Co., Ltd.), Denacol EX-212L, Denacol EX-214L, Denacol EX-216L, Denacol EX-321L and Denacol EX-850L (these are trade names of Nagase Chemtech Co., Ltd.). available at (E) component can be used individually by 1 type or in mixture of 2 or more types.

In the photosensitive resin composition of the present embodiment, the content of component (E) is 5 to 70 parts by mass, preferably 7 to 60 parts by mass, per 100 parts by mass of component (A). It is more preferably 10 to 50 parts by mass. When the amount is 10 parts by mass or more, the photosensitive resin composition tends to be easily formed into a film on a desired support.

((F) solvent)
The photosensitive resin composition of the present embodiment may further contain a solvent as the component (F) in order to improve the handleability of the photosensitive resin composition and to adjust the viscosity and storage stability. . Component (F) is preferably an organic solvent. The type of organic solvent is not particularly limited as long as it can exhibit the above performance.

Component (F) includes, for example, ethylene glycol monoalkyl ether acetate such as ethylene glycol monomethyl ether acetate and ethylene glycol monoethyl ether acetate; propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether; propylene glycol monoalkyl ether such as propylene glycol dimethyl ether, propylene glycol diethyl ether, propylene glycol dipropyl ether, propylene glycol dibutyl ether; propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol mono Propylene glycol monoalkyl ether acetate such as propyl ether acetate and propylene glycol monobutyl ether acetate Cellosolve such as ethyl cellosolve and butyl cellosolve Carbitol such as butyl carbitol Lactic acid such as methyl lactate, ethyl lactate, n-propyl lactate and isopropyl lactate Esters; aliphatic carboxylic acid esters such as ethyl acetate, n-propyl acetate, isopropyl acetate, n-butyl acetate, isobutyl acetate, n-amyl acetate, isoamyl acetate, isopropyl propionate, n-butyl propionate, and isobutyl propionate; esters such as methyl 3-methoxypropionate, ethyl 3-methoxypropionate, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, methyl pyruvate, and ethyl pyruvate; aromatic hydrocarbons such as toluene and xylene; methyl ethyl ketone ketones such as , 2-butanone, 2-heptanone, 3-heptanone, 4-heptanone and cyclohexanone; amides such as N,N-dimethylformamide, N-methylacetamide, N,N-dimethylacetamide and N-methylpyrrolidone; γ - Lactones such as butyrolactone. (F) component can be used individually by 1 type or in mixture of 2 or more types.

The content of component (F) is preferably 30 to 200 parts by mass, more preferably 40 to 120 parts by mass, per 100 parts by mass of the total amount of the photosensitive resin composition excluding component (F).

((G) a compound having a Si—O bond)
The photosensitive resin composition of the present embodiment may further contain a compound having a Si—O bond as component (G). Component (G) is not particularly limited as long as it has a Si—O bond. is mentioned. (G) component can be used individually by 1 type or in mixture of 2 or more types.

When an inorganic filler is used as component (G), the inorganic filler is preferably silica such as fused spherical silica, fused and pulverized silica, fumed silica, and sol-gel silica. Further, the inorganic filler may have Si—O bonds by treating the inorganic filler with a silane compound. Among inorganic fillers treated with a silane compound, inorganic fillers other than silica include aluminum oxide, aluminum hydroxide, calcium carbonate, calcium hydroxide, barium sulfate, barium carbonate, magnesium oxide, magnesium hydroxide, or talc, Inorganic fillers derived from minerals such as mica can be mentioned.

When a silane compound is used as component (G), the silane compound is not particularly limited as long as it has a Si—O bond. Silane compounds include, for example, alkylsilanes, alkoxysilanes, vinylsilanes, epoxysilanes, aminosilanes, acrylsilanes, methacrylsilanes, mercaptosilanes, sulfidesilanes, isocyanatesilanes, sulfursilanes, styrylsilanes, and alkylchlorosilanes.

As the silane compound (G), a compound represented by the following general formula (14) is preferable.
(R ¹⁰¹ O) _4-f -Si-(R ¹⁰² ) _f (14)

In formula (14), R ¹⁰¹ represents an alkyl group having 1 to 10 carbon atoms such as a methyl group, an ethyl group, a propyl group, R ¹⁰² represents a monovalent organic group, f is 0 to Indicates an integer of 3. When f is 0, 1 or 2, multiple R ¹⁰¹ may be the same or different. When f is 2 or 3, multiple R ¹⁰² may be the same or different. R ¹⁰¹ is preferably an alkyl group having 1 to 5 carbon atoms, more preferably an alkyl group having 1 to 2 carbon atoms, from the viewpoint of further improving resolution. In order to improve the dispersibility of the inorganic filler, when treated with the compound represented by the general formula (14), from the viewpoint of further improving the dispersibility of the inorganic filler, f is preferably 0 to 2, and 0 to 1. is more preferred.

Examples of silane compounds include methyltrimethoxysilane, dimethyldimethoxysilane, trimethylmethoxysilane, methyltriethoxysilane, methyltriphenoxysilane, ethyltrimethoxysilane, n-propyltrimethoxysilane, diisopropyldimethoxysilane, and isobutyltrimethoxysilane. , diisobutyldimethoxysilane, isobutyltriethoxysilane, n-hexyltrimethoxysilane, n-hexyltriethoxysilane, cyclohexylmethyldimethoxysilane, n-octyltriethoxysilane, n-dodecyltrimethoxysilane, phenyltrimethoxysilane, diphenyldimethoxysilane silane, tetraethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-(2-aminoethyl)aminopropyltrimethoxysilane, 3-(2-aminoethyl)aminopropylmethyldimethoxysilane, 3-phenylaminopropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, Bis(3-(triethoxysilyl)propyl)disulfide, bis(3-(triethoxysilyl)propyl)tetrasulfide, vinyltriacetoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltriisopropoxysilane, allyltri Methoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyl Triethoxysilane and N-(1,3-dimethylbutylidene)-3-aminopropyltriethoxysilane are included.

The content of component (G) is preferably 0.5 to 10 parts by mass, more preferably 1 to 8 parts by mass, per 100 parts by mass of component (A).

The photosensitive resin composition of the present embodiment optionally contains miscible additives such as additional resins for improving resist pattern performance, plasticizers, stabilizers, colorants, coupling agents, A conventionally known agent such as a leveling agent can be appropriately contained.

[Photosensitive film]
The photosensitive film of this embodiment comprises a support and a photosensitive layer formed from the above-described photosensitive resin composition provided on the support. A protective layer covering the photosensitive layer may be further provided on the photosensitive layer.

As the support, a polymer film having heat resistance and solvent resistance can be used. Polymer films include, for example, polyester films including polyethylene terephthalate and the like, and polyolefin films including polypropylene, polyethylene and the like. The thickness of the support is preferably 5 to 25 μm. The polymer films may be used by laminating one of them as a support and the other as a protective film on both sides of the photosensitive layer so as to sandwich the photosensitive layer.

A polymer film having heat resistance and solvent resistance can be used as the protective layer. Polymer films include, for example, polyester films including polyethylene terephthalate and the like, and polyolefin films including polypropylene, polyethylene and the like.

The photosensitive layer can be formed by applying the photosensitive resin composition of the present embodiment onto a support or protective layer. Examples of coating methods include dipping, spraying, bar coating, roll coating and spin coating. Although the thickness of the photosensitive layer varies depending on the application, it is preferably 10 to 100 μm, more preferably 15 to 60 μm, particularly preferably 20 to 50 μm after drying the photosensitive layer.

[Method of forming a resist pattern]
A method for forming a resist pattern according to an embodiment includes steps of applying the above-described photosensitive resin composition onto a substrate and drying the applied photosensitive resin composition to form a photosensitive layer; After pattern exposure, the method can include a step of heat-treating, a step of developing the heat-treated photosensitive layer to obtain a resin pattern, and a step of heat-treating the resin pattern. Further, the method for forming a resist pattern of the embodiment includes the steps of disposing the photosensitive layer of the above-described photosensitive film on a substrate, exposing the photosensitive layer to a predetermined pattern and then heat-treating it, and A step of developing the photosensitive layer to obtain a resin pattern and a step of heat-treating the resin pattern may be provided.

In the resist pattern forming method of the present embodiment, for example, first, a photosensitive layer containing the above-described photosensitive resin composition is formed on a substrate on which a resist pattern is to be formed. Examples of the method for forming the photosensitive layer include a method of applying (for example, coating) a photosensitive resin composition to a substrate and drying to volatilize a solvent or the like to form a photosensitive layer (coating film); A method of transferring (laminating) a photosensitive layer in an element onto a base material can be used.

A substrate etc. are mentioned as a base material. As the substrate, for example, a copper foil coated with a resin, a copper clad laminate, a silicon wafer with a sputtered metal film, a silicon wafer with a copper plating film, an alumina substrate, or the like can be used. The surface of the substrate on which the photosensitive layer is formed may be a cured resin layer formed using a photosensitive resin composition. In that case, there is a tendency for the adhesion to the substrate to improve.

As a method for applying the photosensitive resin composition to the substrate, for example, a dipping method, a spray method, a bar coating method, a roll coating method, a spin coating method, or the like can be used. The thickness of the photosensitive layer can be appropriately controlled by adjusting the coating means, solid content concentration and viscosity of the photosensitive resin composition.

Next, the photosensitive layer is exposed to a predetermined pattern through a predetermined mask pattern. Actinic rays used for exposure include, for example, g-line stepper light rays; low-pressure mercury lamps, high-pressure mercury lamps, metal halide lamps, i-line stepper ultraviolet rays; electron beams; Although it is appropriately selected depending on the thickness of the photosensitive layer, for example, in the case of ultraviolet irradiation from a high-pressure mercury lamp, it is about 100 to 5000 mJ/cm ² when the thickness of the photosensitive layer is 10 to 50 μm.

Further, heat treatment (post-exposure bake) is performed after exposure. By performing post-exposure baking, the curing reaction of component (A) by the acid generated from component (B) can be accelerated. The post-exposure baking conditions vary depending on the composition of the photosensitive resin composition, the content of each component, the thickness of the photosensitive layer, etc., but usually it is preferable to heat at 70 to 150° C. for 1 to 60 minutes, and 80 to 120° C. C. for 1 to 60 minutes is more preferred.

Then, the exposed and/or post-exposure baked photosensitive layer is developed with a developer to dissolve and remove the unexposed areas (areas other than the cured areas) to obtain a desired resin pattern. Examples of the developing method in this case include a shower developing method, a spray developing method, an immersion developing method, a puddle developing method, and the like. The development conditions are usually 20 to 40° C. for 1 to 10 minutes.

Examples of the developer include organic solvents and alkaline aqueous solutions. Organic solvents include, for example, N-methylpyrrolidone, ethanol, cyclohexanone, cyclopentanone and propylene glycol methyl ether acetate. Examples of alkaline aqueous solutions include aqueous solutions containing sodium hydroxide, potassium hydroxide, sodium silicate, ammonia, ethylamine, diethylamine, triethylamine, triethanolamine, tetramethylammonium hydroxide, and the like. Among these, propylene glycol methyl ether acetate is preferable from the viewpoint of development speed.

After development, it is preferable to rinse with water, methanol, ethanol, isopropyl alcohol, n-butyl acetate, propylene glycol monomethyl ether acetate, diethylene glycol dimethyl ether acetate or the like, if necessary.

Furthermore, a cured film (resist pattern) of the photosensitive resin composition is obtained by performing a heat treatment to develop insulating film properties. The conditions for the heat treatment are not particularly limited, but the photosensitive resin composition can be cured by heating at 50 to 250° C. for 30 minutes to 10 hours depending on the intended use of the cured product.

Also, the heating can be carried out in two stages in order to sufficiently progress the curing and to prevent deformation of the obtained resin pattern shape. For example, the first stage may be heated at 50 to 120° C. for 5 minutes to 2 hours, and the second stage may be cured by heating at 80 to 200° C. for 10 minutes to 10 hours. The heating equipment is not particularly limited, and a general oven, infrared furnace, etc. can be used.

[Method for Forming Hollow Structure]
The resist pattern forming method of this embodiment is suitable as a method of forming a rib pattern for forming a hollow structure.

The method for forming a hollow structure according to the present embodiment comprises providing a rib pattern for forming a hollow structure, and laminating the above-described photosensitive film on the rib pattern so as to form a lid of the hollow structure. an exposure step of irradiating a predetermined portion of the photosensitive layer with actinic rays to photo-cure the exposed portion; and a thermosetting step of thermally curing the exposed portion of the photosensitive layer to form a cured product.

The photosensitive film can be used not only as a material for forming the rib portion of the hollow structure, but also as a material for forming the lid portion. When a photosensitive film is applied as a lid, it is not necessary to pass through a development step between the exposure step and the thermal curing step.

However, when it is desired to control the shape of the lid, when it is desired to manufacture a plurality of hollow structure devices at once, and after exposing only the size corresponding to the lid of the individual hollow device through the mask, the surrounding unexposed portion is exposed. In the case of dividing into individual pieces by developing, etc., in the exposure process, after passing through the exposure process of irradiating actinic rays through a mask to photo-harden the exposed part, the part other than the exposed part of the photosensitive layer is removed. It is preferable to pass through the development process which removes using the above-mentioned developer.

The thickness of the photosensitive layer used to form the lid is preferably 5-500 μm, more preferably 10-400 μm. The final thickness of the lid formed through the curing step (total thickness of the photosensitive layer, substrate film or thin plate) is preferably 10 μm to 3 mm, more preferably 20 μm to 2 mm. By using the photosensitive resin composition of the present embodiment, the shape can be maintained even if the thickness of the cover is 10 μm, and deformation under high temperature and high pressure conditions during molding can be suppressed. On the other hand, if the thickness of the lid portion is 3 mm or less, it is possible to avoid problems that may arise in manufacturing due to the hollow structure device being too thick and the light transmittance at the time of exposure being reduced.

The thickness of the lid can be adjusted to a desired thickness not only by the thickness of the photosensitive layer but also by leaving the support as it is as the lid.

The lid portion and the rib pattern can be bonded by, for example, thermocompression bonding using a press, a roll laminator, or a vacuum laminator. The rib pattern may be produced without using the photosensitive resin composition of the present embodiment, and only the lid portion may be formed using the photosensitive resin composition of the present embodiment. It is preferable to use the photosensitive resin composition of the present embodiment for both because the adhesion therebetween is excellent. If the provided rib pattern has a sufficient film thickness, a hollow structure can be formed by laminating a ceramic substrate, a Si substrate, a glass substrate, a metal substrate, or the like as a lid.

According to the method for forming a hollow structure according to the present embodiment, a thick-film rib pattern can be collectively formed by photolithography. A hollow structure can be formed by sealing with the sealing substrate) as a lid.

In addition, since the space of this hollow structure is moisture-proofed by the surrounding photosensitive resin composition and the hollow space is maintained even at high temperatures, a hollow structure such as a SAW filter, CMOS/CCD sensor, or MEMS is required. It can be applied to electronic parts, and is useful for making electronic parts smaller, thinner, and more functional. The photosensitive resin composition of the present embodiment is particularly suitable as a material for forming the ribs and lid of the hollow structure of the SAW filter, and is particularly suitable as a material for forming the lid in that high reliability can be achieved. there is

As described above, the photosensitive resin composition of the present embodiment is suitable as a material for forming ribs and/or lids for hollow structure devices. In addition, by applying the photosensitive film of the present embodiment to the method of forming a rib pattern and the method of forming a hollow structure, a low-cost and highly reliable hollow structure electronic component, specifically a SAW filter, can be manufactured. can do. The photosensitive resin composition of this embodiment can be applied as a material used for a surface protective film or an interlayer insulating film of a semiconductor device. Moreover, it can be applied as a material used for a solder resist or an interlayer insulating film of a wiring board material. In particular, the photosensitive resin composition of the present embodiment has good resolution and insulation reliability between fine wirings after curing. It is preferably used for

Examples of the present invention will be described below, but the present invention is not limited to these examples.

(Synthesis example 1)
After adding 500 mL of superdehydrated diethyl ether and 30 g (121.46 mmol) of pentafluorobromobenzene to a 125 mL four-necked flask sufficiently dried under a nitrogen atmosphere, cool to −78° C. using a dry ice/acetone bath. bottom. Next, 47.4 mL of a 2.5 mol/L n-butyllithium hexane solution was added dropwise to the flask over 10 minutes, and the mixture was stirred at -78°C for 30 minutes. To this, 49.3 mL of a 0.6 mol/L gallium (III) chloride diethyl ether solution was added dropwise over 10 minutes, and the reaction was carried out with stirring at -78°C for 3 hours. The reaction solution was stirred while gradually returning to room temperature, and stirred at room temperature for 5 hours. After the reaction solution was filtered to remove the precipitate, it was concentrated under reduced pressure to obtain an off-white product. After washing the product four times with 30 mL of ultra-dehydrated hexane, it was vacuum-dried overnight to obtain lithium tetrakis(pentafluorophenyl)gallate.

(Synthesis example 2)
25 mL of dichloromethane, 1.69 g (5 mmol) of 4-isopropylphenyl(p-tolyl)iodonium chloride, and 4.4 g (6 mmol) of lithium tetrakis(pentafluorophenyl)gallate were added to a 50 mL round-bottomed flask and stirred at room temperature for 2 hours. reacted while The reaction mixture was filtered to remove precipitates, and concentrated under reduced pressure to obtain 4-isopropylphenyl(p-tolyl)iodonium tetrakis(pentafluorophenyl)gallate (B-3).

(Synthesis Example 3)
1.6 g (8 mmol) of diphenyl sulfoxide, 1.5 g (8 mmol) of diphenyl sulfide, 2.5 g (24 mmol) of acetic anhydride, 1.5 g (10 mmol) of trifluoromethanesulfonic acid and 13 g of acetonitrile were uniformly mixed and heated at 40° C. for 6 hours. reacted. The reaction solution was cooled to room temperature, poured into 60 g of distilled water, extracted with 60 g of dichloromethane, and washed with water until the pH of the aqueous layer became neutral. The dichloromethane layer was concentrated under reduced pressure to obtain a brown liquid product. Add 20 g of ethyl acetate to the product and dissolve in a water bath at 60°C, add 60 g of hexane and stir, cool to 5°C, allow to stand for 30 minutes, remove the supernatant, and remove the supernatant twice. washed. The solution containing the washed product was concentrated under reduced pressure to give diphenyl[4-(phenylthio)phenyl]sulfonium triflate. This triflate was dissolved in 50 g of dichloromethane, mixed with 66 g of an aqueous solution containing equimolar lithium tetrakis(pentafluorophenyl)gallate, and reacted at room temperature for 3 hours. The dichloromethane layer of the reaction solution was washed twice with water and then concentrated under reduced pressure to obtain diphenyl[4-(phenylthio)phenyl]sulfonium tetrakis(pentafluorophenyl)gallate (B-4).

[Photosensitive resin composition]
Each component shown in Tables 1 and 2 was blended (unit: parts by mass) to prepare photosensitive resin compositions of Examples and Comparative Examples.

The abbreviations of the components in Tables 1 and 2 are as follows.
(A-1): Polyfunctional bisphenol novolac type epoxy resin (trade name of Mitsubishi Chemical Corporation: jER157S70)
(A-2): p-hydroxystyrene-styrene copolymer (trade name of Maruzen Petrochemical Co., Ltd.: Marukalinker CST-70, Mw: 10000)
(B-1): Triarylsulfonium tetrakis(pentafluorophenyl)borate (product name of San-Apro Co., Ltd.: CPI-110B)
(B-2): Triarylsulfonium tetrakis(pentafluorophenyl)borate (product name of San-Apro Co., Ltd.: CPI-310B)
(B-3): Onium gallate salt of Synthesis Example 2 (B-4): Onium gallate salt of Synthesis Example 3 (B-5): Triarylsulfonium hexafluoroantimonate (San-Apro Co., Ltd. trade name: CPI-310A )
(B-6): triarylsulfonium hexafluoroantimonate (product name of San-Apro Co., Ltd.: CPI-101A)
(B-7): Triarylsulfonium hexafluorophosphate (product name of San-Apro Co., Ltd.: CPI-310P)
(C-1): Polyfunctional methylol compound (trade name of Honshu Chemical Industry Co., Ltd.: HMOM-TPPA)
(D-1): 9,10-dibutoxyanthracene (trade name of Kawasaki Chemical Industries, Ltd.: DBA)
(E-1): Trimethylolpropane triglycidyl ether (product name of Nagase ChemteX Corporation: EX-321L)
(F-1): Propylene glycol methyl ether acetate (trade name of Fujifilm Wako Pure Chemical Industries, Ltd.: 2-methoxy-1-methylethyl acetate)
(F-2): Methyl ethyl ketone (trade name of Fujifilm Wako Pure Chemical Industries, Ltd.: 2-butanone)
(G-1): 3-glycidoxypropyltrimethoxysilane (trade name of Shin-Etsu Chemical Co., Ltd.: KBM-403)

[Preparation of photosensitive film]
A polyethylene terephthalate film (trade name: A-4100 available from Teijin Limited) having a thickness of 50 μm was prepared as a support. The photosensitive resin composition of Examples or Comparative Examples was uniformly coated on the support so that the thickness after drying was 30 μm. Next, a photosensitive layer was formed by heating and drying at 100° C. for 15 minutes using a hot air convection dryer to produce a photosensitive film having a support and a photosensitive layer.

[evaluation]
(pattern formability)
The photosensitive film was laminated on a 6-inch silicon wafer with the photosensitive layer facing the silicon wafer to obtain a laminate comprising a 30 μm photosensitive layer and a support. Lamination was performed at 60° C. using a laminator. A resolution evaluation mask (having a pattern in which the width of the exposed area and the unexposed area is 1:1 from 10 μm: 10 μm to 100 μm: 100 μm in increments of 10 μm was used) on the support of the laminate. , and an i-line filter (trade name: HB-0365 available from Asahi Spectrosco Co., Ltd.) was placed thereon, and exposed at 250 mJ/cm ² using a high-precision parallel exposure machine (manufactured by Mikasa Co., Ltd.). The exposed samples were post-exposure baked on a hot plate at 85° C. for 4 minutes.

After removing the support, the photosensitive layer was subjected to paddle development for development times of 60 seconds and 30 seconds using a developer (propylene glycol methyl ether acetate) and a developing machine (trade name: AD-1200 manufactured by Takizawa Sangyo Co., Ltd.). and removed the unexposed portion to obtain a resin pattern. The developed resin pattern was dried at room temperature for 30 minutes to obtain a sample for evaluation. The pattern formability (resolution) was evaluated by observing the sample using a metallurgical microscope. Evaluation was performed according to the following criteria. Here, "formable" means that the unexposed portion is cleanly removed and the line portion (exposed portion) is free from defects such as collapse. Table 3 shows the evaluation results.
A: A pattern with a line width of 40 μm or less could be formed.
B: A pattern with a line width of 80 μm or less could be formed.
C: The photosensitive layer was peeled off after development.

(HAST resistance)
Etching the copper surface of a printed wiring board substrate (trade name: MCL E-679 from Hitachi Chemical Co., Ltd.) having a structure in which a 12 μm thick copper foil is laminated on a glass epoxy base material, the line / space is 50 μm / 50 μm. A comb-shaped electrode was formed. Using this substrate as an evaluation substrate, a photosensitive film was used to form a cured product of the photosensitive layer on the substrate in the same manner as in the above (Evaluation of pattern formability). After that, it was tested for 100 hours under conditions of 130° C., 85% RH, and 3.3 V. The copper wiring after the test was observed to evaluate HAST resistance. A case where corrosion of the copper wiring was not observed before and after the test was judged as "A", and a case where corrosion of the copper wiring was observed was judged as "B". Table 3 shows the evaluation results.

From Table 3, it was confirmed that Examples 1 to 7 were superior to Comparative Examples 1 to 5 in both pattern formability and HAST resistance, and were excellent in insulation reliability between fine wirings.

Claims (8)

(A) a polyfunctional phenolic novolac epoxy resin;
(B) a photosensitive acid generator containing at least one onium salt selected from the group consisting of onium borate salts and onium gallate salts;
(C) a compound having a methylol group or an alkoxyalkyl group,
The onium borate salt contains an anion consisting of tetrakis(pentafluorophenyl)borate,
The photosensitive resin composition, wherein the (C) compound having a methylol group or an alkoxyalkyl group is a compound further having a phenolic hydroxyl group. 2. The photosensitive resin composition according to claim 1, wherein said onium salt contains at least one cation selected from the group consisting of iodonium and sulfonium. 3. The photosensitive resin composition according to claim 1 , further comprising (D) a sensitizer. 4. The photosensitive resin composition according to any one of claims 1 to 3 , further comprising (E) an aliphatic or alicyclic epoxy compound having two or more oxirane rings. A photosensitive film comprising a support and a photosensitive layer formed from the photosensitive resin composition according to any one of claims 1 to 4 provided on the support. A device comprising a cured product of the photosensitive resin composition according to any one of claims 1 to 4 . A step of applying the photosensitive resin composition according to any one of claims 1 to 4 onto a substrate and drying the applied photosensitive resin composition to form a photosensitive layer;
a step of heat-treating after exposing the photosensitive layer to a predetermined pattern;
a step of developing the photosensitive layer after the heat treatment to obtain a resin pattern;
a step of heat-treating the resin pattern;
A method of forming a resist pattern, comprising: disposing the photosensitive layer of the photosensitive film according to claim 5 on a substrate;
a step of heat-treating after exposing the photosensitive layer to a predetermined pattern;
a step of developing the photosensitive layer after the heat treatment to obtain a resin pattern;
a step of heat-treating the resin pattern;
A method of forming a resist pattern, comprising: