JP2015219491A - Polyimide precursor, photosensitive resin composition containing the polyimide precursor, and cured-pattern-film manufacturing method and semiconductor device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photosensitive resin composition wherein an obtained cured film exhibits low stress, and adhesion to base material at development is good as well as adhesion after curing in a developed film is good.SOLUTION: A photosensitive resin composition comprises (a) a polyimide precursor including a structural unit represented by the following formula (1), (b) a compound that generates radicals when irradiated with active rays, (c) a compound represented by the following formula (c-1), and (d) a solvent.

Description

  The present invention relates to a polyimide precursor, a photosensitive resin composition containing the polyimide precursor, a method for producing a patterned cured film using the same, and a semiconductor device.

As a protective film material for a semiconductor integrated circuit (LSI), an organic material having high heat resistance such as polyimide resin is widely applied.
A protective film (cured film) using such a polyimide resin is obtained by heating and curing a resin film formed by applying and drying a polyimide precursor or a resin composition containing a polyimide precursor on a substrate. can get.

In recent years, with the miniaturization of semiconductor integrated circuits, it is necessary to reduce the dielectric constant of an interlayer insulating film called a low-k layer. In order to reduce the dielectric constant, for example, there is a method of applying an interlayer insulating film having a hole structure. However, this method has a problem that the mechanical strength is lowered. In order to protect such an interlayer insulating film having low mechanical strength, there is a method of providing a protective film on the interlayer insulating film.
In addition, in the region where the protruding external electrodes called bumps are formed, the stress acting on the interlayer insulating film is concentrated and the interlayer insulating film is not destroyed. 5 μm or more) and higher elastic modulus (for example, 4 GPa or more) are increasing. However, by increasing the thickness of the protective film and increasing the elastic modulus, the stress of the protective film increases and the warp of the semiconductor wafer increases, which may cause problems during transportation and wafer fixing. Therefore, there is a demand for development of low stress polyimide resin.

  As a method for reducing the stress of the polyimide resin, a method in which the molecular chain of the polyimide is made to have a rigid skeleton in order to make the thermal expansion coefficient of the polyimide close to the thermal expansion coefficient of the silicon wafer (for example, Patent Document 1). A method for reducing the elastic modulus of polyimide by introducing a flexible structure is proposed (for example, Patent Document 2).

  By the way, when the polyimide resin used for forming the protective film is photosensitive, it is possible to easily form a pattern resin film (patterned resin film). By heating and curing such a patterned resin film, a pattern cured film (patterned cured film) can be easily formed.

  As a method for making polyimide resin photosensitive, a method of introducing a (meth) acryloyl group into a polyimide precursor via an ester bond or an ionic bond, a method of using a soluble polyimide having a photopolymerizable olefin, and a benzophenone skeleton In addition, a method using a self-sensitized polyimide having an alkyl group at the ortho position of an aromatic ring to which a nitrogen atom is bonded is known (for example, Patent Document 3). Among these methods, the method of introducing a (meth) acryloyl group via an ester bond into a polyimide precursor can freely select a monomer to be used when synthesizing the polyimide precursor. ) Since the acryloyl group is introduced through a chemical bond, it is characterized by excellent stability over time.

However, in order to obtain the low-stress polyimide resin, when a large amount of aromatic ring units are introduced into the molecular chain of the polyimide resin and the molecular chain is made into a rigid skeleton, there are many conjugated aromatic ring units in the molecular chain. Even if it is a polyamic acid (polyimide precursor) which is a precursor of a polyimide resin, it will have absorption in an ultraviolet region. Therefore, the transmittance of i-line (wavelength 365 nm) widely used in the exposure process for forming the patterned resin film tends to decrease, and the sensitivity and resolution tend to decrease. In addition, when a flexible structure such as a siloxane structure is introduced, the heat resistance may decrease.
Furthermore, when the protective film is made thicker, the i-line transmittance tends to further decrease, and the pattern resin film cannot be formed.

To solve these problems, there is a method of using a polyimide precursor containing fluorine in order to increase the i-line transmittance of the coating film.
However, the cured film obtained after heat curing the fluorine-containing polyimide precursor has a drawback that the adhesion of the substrate to the silicon wafer is low (for example, Patent Document 4 or 5).

  Moreover, in order to give the outstanding adhesiveness with a silicon wafer, what used 3-isocyanatopropyl triethoxysilane for the resin composition is reported (for example, patent document 6). However, since it has a highly reactive isocyanate group, there is a problem that the storage stability of the resin composition is deteriorated. In addition, the rigid polyimide precursor, which has a low CTE after curing, generates a stress with the silicon wafer when it is applied to the silicon wafer and heated before exposure (when it is made into a resin film). There is a problem that the film is easily peeled off from the silicon wafer.

JP-A-5-295115 JP 7-304950 A JP-A-7-242744 Japanese Patent No. 2826940 Japanese Patent No. 4144110 JP 11-338157 A

  In order to solve the above problems, the present invention provides a photosensitive resin composition in which a cured film obtained has low stress and excellent adhesion during development with a substrate, and a pattern using the photosensitive resin composition It aims at providing the manufacturing method of a cured film.

（式（１）中、Ａは、下記式（２）で表される４価の有機基のいずれかである。
Ｂは、下記式（３）で表される２価の有機基である。
Ｒ^１及びＲ^２は、各々独立に水素原子又は１価の有機基である。）

（式（２）中、Ｘ及びＹは、各々独立に各々が結合するベンゼン環と共役しない２価の基又は単結合を示す。）

（式（３）中、Ｒ^３〜Ｒ^１０の少なくとも１つは、フッ素原子、トリフルオロメチル基、又はメチル基であり、他は水素原子である。）

（式（ｃ−１）中、
Ｒ^１１は、各々独立に、炭素数１〜４のアルキル基である。
Ｒ^１２は、各々独立に、水酸基又は炭素数１〜４のアルキル基である。
ａは、１〜３の整数である。
ｎは、１〜６の整数である。
Ｒ^１３は、エポキシ基を有する有機基、又はジヒドロキシエチルアミノ基を有する有機基である。）
＜２＞前記（ａ）成分が下記式（４）で表される構造単位を有するポリイミド前駆体である＜１＞に記載の感光性樹脂組成物。

（式（４）中、Ｄは下記一般式（５）で表される４価の有機基である。
Ｂ、Ｒ^１及びＲ^２は、それぞれ前記式（１）と同じである。）

（式（５）中、Ｚは酸素原子又は硫黄原子である。）
＜３＞前記式（１）と前記式（４）のモル比が５／５〜９／１である＜１＞又は＜２＞に記載の感光性樹脂組成物。
＜４＞前記式（１）のＲ^１又はＲ^２が炭素炭素不飽和二重結合を有する１価の有機基である＜１＞〜＜３＞のいずれかに記載の感光性樹脂組成物。
＜５＞テトラゾール、テトラゾール誘導体、ベンゾトリアゾール又はベンゾトリアゾール誘導体を含有する＜１＞〜＜４＞のいずれかに記載の感光性樹脂組成物。
＜６＞前記（ｂ）成分がオキシムエステル化合物である＜１＞〜＜５＞のいずれかに記載の感光性樹脂組成物。
＜７＞前記オキシムエステル化合物が、下記式（２２）で表される化合物、下記式（２３）で表される化合物、又は下記一般式（２４）で表される化合物である＜６＞に記載の感光性樹脂組成物。

（式（２２）中、Ｒ_１１及びＲ_１２は、それぞれ炭素数１〜１２のアルキル基、炭素数４〜１０のシクロアルキル基、フェニル基又はトリル基である。
Ｒ_１３は、−Ｈ、−ＯＨ、−ＣＯＯＨ、−Ｏ（ＣＨ_２）ＯＨ、−Ｏ（ＣＨ_２）_２ＯＨ、−ＣＯＯ（ＣＨ_２）ＯＨ、又は−ＣＯＯ（ＣＨ_２）_２ＯＨである。）

（式（２３）中、Ｒ_１４は、それぞれ炭素数１〜６のアルキル基である。
Ｒ_１５は、ＮＯ_２又はＡｒＣＯ（Ａｒはアリール基である。）である。
Ｒ_１６及びＲ_１７は、それぞれ炭素数１〜１２のアルキル基、フェニル基、又はトリル基である。）

（式（２４）中、Ｒ_１８は、炭素数１〜６のアルキル基である。
Ｒ_１９はアセタール結合を有する有機基である。
Ｒ_２０及びＲ_２１は、それぞれ炭素数１〜１２のアルキル基、フェニル基、又はトリル基である。）
＜８＞３−ウレイドプロピルトリエトキシシラン、３−メタクリロキシプロピルトリメトキシシラン、３−メルカプトプロピルトリメトキシシラン、トリエトキシシリルプロピルエチルカルバメート、又は３−[２−（３−トリエトキシシリルプロポキシ）エトキシ]スルホランを含有する＜１＞〜＜７＞のいずれかに記載の感光性樹脂組成物。
＜９＞前記＜１＞〜＜８＞のいずれかに記載の感光性樹脂組成物を加熱して得られるパターン硬化膜。
＜１０＞前記＜１＞〜＜８＞のいずれかに記載の感光性樹脂組成物を基板上に塗布し乾燥して塗膜を形成する工程、
前記形成した塗膜に活性光線を照射してパターン状に露光する工程、
前記露光部以外の未露光部を現像によって除去してパターン樹脂膜を得る工程、及び
パターン樹脂膜を加熱処理する工程を含むパターン硬化膜の製造方法。
＜１１＞前記＜１０＞に記載のパターン硬化膜の製造方法で得られるパターン硬化膜を有する半導体装置。 Specific embodiments of the present invention are shown below.
<1> A photosensitive resin composition containing the following components (a) to (d).
(A) Polyimide precursor having a structural unit represented by the following formula (1) (b) Compound that generates radicals upon irradiation with actinic rays (c) Compound represented by the following formula (c-1) (d) Solvent

(In Formula (1), A is either the tetravalent organic group represented by following formula (2).
B is a divalent organic group represented by the following formula (3).
R ¹ and R ² are each independently a hydrogen atom or a monovalent organic group. )

(In Formula (2), X and Y each independently represent a divalent group or a single bond that is not conjugated to the benzene ring to which each is bonded.)

(In Formula (3), at least one of R ^{3 to} R ¹⁰ is a fluorine atom, a trifluoromethyl group, or a methyl group, and the other is a hydrogen atom.)

(In the formula (c-1),
R ¹¹ is each independently an alkyl group having 1 to 4 carbon atoms.
R < ¹² > is respectively independently a hydroxyl group or a C1-C4 alkyl group.
a is an integer of 1 to 3.
n is an integer of 1-6.
R ¹³ is an organic group having an epoxy group or an organic group having a dihydroxyethylamino group. )
<2> The photosensitive resin composition according to <1>, wherein the component (a) is a polyimide precursor having a structural unit represented by the following formula (4).

(In formula (4), D is a tetravalent organic group represented by the following general formula (5).
B, R ¹ and R ² are the same as those in the formula (1), respectively. )

(In Formula (5), Z is an oxygen atom or a sulfur atom.)
<3> The photosensitive resin composition according to <1> or <2>, wherein the molar ratio of the formula (1) to the formula (4) is 5/5 to 9/1.
<4> The photosensitive resin composition according to any one of <1> to <3>, wherein R ¹ or R ^{2 in} the formula (1) is a monovalent organic group having a carbon-carbon unsaturated double bond.
The photosensitive resin composition in any one of <1>-<4> containing <5> tetrazole, a tetrazole derivative, a benzotriazole, or a benzotriazole derivative.
<6> The photosensitive resin composition according to any one of <1> to <5>, wherein the component (b) is an oxime ester compound.
<7> The above oxime ester compound is a compound represented by the following formula (22), a compound represented by the following formula (23), or a compound represented by the following general formula (24). Photosensitive resin composition.

(In the formula _{(22), R 11} and _{R 12} are each an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 4 to 10 carbon atoms, a phenyl group or a tolyl group.
R ₁₃ is —H, —OH, —COOH, —O (CH ₂ ) OH, —O (CH ₂ ) ₂ OH, —COO (CH ₂ ) OH, or —COO (CH ₂ ) ₂ OH. )

(In Formula (23), R < ₁₄ > is a C1-C6 alkyl group, respectively.
R ₁₅ is NO ₂ or ArCO (Ar is an aryl group).
R ₁₆ and R ₁₇ are each an alkyl group having 1 to 12 carbon atoms, a phenyl group, or a tolyl group. )

(In the formula _{(24), R 18} is an alkyl group having 1 to 6 carbon atoms.
R ₁₉ is an organic group having an acetal bond.
R ₂₀ and R ₂₁ are each an alkyl group having 1 to 12 carbon atoms, a phenyl group, or a tolyl group. )
<8> 3-Ureidopropyltriethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, triethoxysilylpropylethylcarbamate, or 3- [2- (3-triethoxysilylpropoxy) ethoxy ] The photosensitive resin composition in any one of <1>-<7> containing a sulfolane.
<9> A patterned cured film obtained by heating the photosensitive resin composition according to any one of <1> to <8>.
<10> A step of applying the photosensitive resin composition according to any one of <1> to <8> onto a substrate and drying to form a coating film,
Irradiating an actinic ray to the formed coating film and exposing it in a pattern,
A method for producing a patterned cured film, comprising: removing a non-exposed portion other than the exposed portion by development to obtain a patterned resin film; and heating the pattern resin film.
<11> A semiconductor device having a patterned cured film obtained by the method for producing a patterned cured film according to <10>.

  ADVANTAGE OF THE INVENTION According to this invention, the cured film obtained can provide the photosensitive resin composition which is excellent in the adhesiveness at the time of image development with a low stress.

It is a schematic sectional drawing of the semiconductor device which has the rewiring structure which is one Embodiment of this invention.

（式（１）中、Ａは、下記式（２）で表される４価の有機基のいずれかである。
Ｂは、下記式（３）で表される２価の有機基である。
Ｒ^１及びＲ^２は、各々独立に水素原子又は１価の有機基である。）

（式（２）中、Ｘ及びＹは、各々独立に各々が結合するベンゼン環と共役しない２価の基又は単結合を示す。）

（式（３）中、Ｒ^３〜Ｒ^１０の少なくとも１つは、フッ素原子、トリフルオロメチル基、又はメチル基であり、他は水素原子である。）

（式（ｃ−１）中、
Ｒ^１１は、各々独立に、炭素数１〜４のアルキル基である。
Ｒ^１２は、各々独立に、水酸基又は炭素数１〜４のアルキル基である。
ａは、１〜３の整数である。
ｎは、１〜６の整数である。
Ｒ^１３は、エポキシ基を有する有機基、又はジヒドロキシエチルアミノ基を有する有機基である。） [Photosensitive resin composition]
The photosensitive resin composition of the present invention contains the following components (a) to (d).
(A) Polyimide precursor having a structural unit represented by the following formula (1) (b) Compound that generates radicals upon irradiation with actinic rays (c) Compound represented by the following formula (c-1) (d) Solvent

(In Formula (1), A is either the tetravalent organic group represented by following formula (2).
B is a divalent organic group represented by the following formula (3).
R ¹ and R ² are each independently a hydrogen atom or a monovalent organic group. )

(In Formula (2), X and Y each independently represent a divalent group or a single bond that is not conjugated to the benzene ring to which each is bonded.)

(In Formula (3), at least one of R ^{3 to} R ¹⁰ is a fluorine atom, a trifluoromethyl group, or a methyl group, and the other is a hydrogen atom.)

(In the formula (c-1),
R ¹¹ is each independently an alkyl group having 1 to 4 carbon atoms.
R < ¹² > is respectively independently a hydroxyl group or a C1-C4 alkyl group.
a is an integer of 1 to 3.
n is an integer of 1-6.
R ¹³ is an organic group having an epoxy group or an organic group having a dihydroxyethylamino group. )

The photosensitive resin composition of this invention contains the compound represented by Formula (c-1) from a viewpoint of improving the adhesiveness of the film | membrane and silicon wafer at the time of image development. By containing the component (c), the epoxy group or dihydroxyethylamino group reacts with and binds to the carboxyl group or amino group present at the terminal in the component (a) at the stage of heating before exposure. This is considered to improve the adhesion during development.
Hereinafter, each component of the photosensitive resin composition of this invention is demonstrated. “(Meth) acrylate” represents “acrylate” or “methacrylate”, and “(meth) acryloyl group” represents “acryloyl group” or “methacryloyl group”. “A or B” may include not only A and B but also A + B.

（式（１）中、Ａは、下記式（２）で表される４価の有機基のいずれかである。
Ｂは、下記式（３）で表される２価の有機基である。
Ｒ^１及びＲ^２は、各々独立に水素原子又は１価の有機基である。） [Polyimide precursor]
The polyimide precursor as component (a) has a structural unit represented by the following formula (1).

(In Formula (1), A is either the tetravalent organic group represented by following formula (2).
B is a divalent organic group represented by the following formula (3).
R ¹ and R ² are each independently a hydrogen atom or a monovalent organic group. )

（式（２）中、Ｘ及びＹは、各々独立に各々が結合するベンゼン環と共役しない２価の基又は単結合を示す。）

(In Formula (2), X and Y each independently represent a divalent group or a single bond that is not conjugated to the benzene ring to which each is bonded.)

（式（３）中、Ｒ^３〜Ｒ^１０の少なくとも１つは、フッ素原子、トリフルオロメチル基、又はメチル基であり、他は水素原子である。）

(In Formula (3), at least one of R ^{3 to} R ¹⁰ is a fluorine atom, a trifluoromethyl group, or a methyl group, and the other is a hydrogen atom.)

A in Formula (1) is a structure derived from tetracarboxylic dianhydride used as a raw material, and is any of the tetravalent organic groups represented by Formula (2). Regarding X and Y in formula (2), “a divalent group that is not conjugated to the benzene ring to which each is bonded” includes —O—, —C (CH ₃ ) ₂ —, —C (CH ₃ ) (CF _{3 ) -, - C (CF 3} ) 2 -, - Si (CH 3) 2 - and the like.

  Examples of tetracarboxylic dianhydrides that give the structure of A include pyromellitic dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 3,3 ′, 4,4′-biphenyltetracarboxylic Examples thereof include acid dianhydrides and tetracarboxylic dianhydrides represented by formulas (7) to (13). These may be used alone or in combination of two or more.

B in Formula (1) is a structure derived from diamine used as a raw material, and is a divalent organic group represented by Formula (3).
In the formula (3), at least one of R ^{3 to} R ¹⁰ is preferably a fluorine atom or a trifluoromethyl group from the viewpoint of good i-line transmittance and low stress. It is more preferably a fluoromethyl group, and more preferably two or more are trifluoromethyl groups. In formula (3), other R ^{3 to} R ^{10 that} are not a fluorine atom or a trifluoromethyl group are hydrogen atoms.

Examples of the diamine that gives the structure of B include diamines represented by the following formulas (14) to (20). These may be used alone or in combination of two or more.

R ¹ and R ² in the formula (1) are each independently a hydrogen atom or a monovalent organic group. Examples of the monovalent organic group include an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 1 to 20 carbon atoms, and a (meth) acryloxyalkyl group having 1 to 10 carbon atoms in the alkyl moiety.
The photosensitive resin composition of the present invention is a compound in which R ¹ or R ² is a monovalent organic group having a carbon-carbon unsaturated double bond, and generates radicals by actinic ray irradiation of the component (b) described later. In combination, it is preferable to enable cross-linking between molecular chains by radical polymerization. Examples of the monovalent organic group having a carbon-carbon unsaturated double bond include (meth) acryloxyalkyl groups having 1 to 10 carbon atoms in the alkyl moiety.

  Furthermore, the polyimide precursor of component (a) may have a structural unit represented by formula (4) for the purpose of improving i-line transmittance, adhesion after curing, and mechanical properties.

（式（４）中、Ｄは、下記式（５）で表される４価の有機基である。
Ｂは、式（３）で表される２価の有機基である。
Ｒ^１及びＲ^２は、各々独立に水素原子又は１価の有機基である。）

(In Formula (4), D is a tetravalent organic group represented by following formula (5).
B is a divalent organic group represented by the formula (3).
R ¹ and R ² are each independently a hydrogen atom or a monovalent organic group. )

（式（５）中、Ｚは、酸素原子又は硫黄原子である。）

(In Formula (5), Z is an oxygen atom or a sulfur atom.)

B in the formula (4) is the same as B in formula (1), ^{R 1} and ^{R 2} in the formula (4) is the same as ^{R 1} and ^{R 2} in the formula (1).
D in Formula (4) is a structure derived from tetracarboxylic dianhydride used as a raw material, and is a tetravalent organic group represented by Formula (5).
Examples of tetracarboxylic dianhydrides that give the structure of D include 4,4′-oxydiphthalic dianhydride, 4,4′-thiodiphthalic dianhydride, and the like. These may be used alone or in combination of two kinds.

  In the polyimide precursor having the structural unit represented by the formula (1) and the structural unit represented by the formula (5), from the viewpoint of achieving both low stress and good i-line transmittance, the formula (1) And the molar ratio of formula (5) (formula (1) / formula (5)) is preferably 5/5 to 9/1, more preferably 6/4 to 9/1, and 7/3 More preferably, it is ˜9 / 1.

  There is no restriction | limiting in particular in the synthesis | combining method of the polyimide precursor of a component (a), It can synthesize | combine by a conventionally well-known method.

  It is preferable to contain 20-60 mass% of polyimide precursors in the photosensitive resin composition, It is more preferable to contain 25-55 mass%, It is more preferable to contain 30-55 mass%.

[Compounds that generate radicals upon irradiation with actinic rays]
As the compound that generates radicals upon irradiation with actinic rays as the component (b), N, N ′ such as an oxime ester compound, benzophenone, N, N′-tetramethyl-4,4′-diaminobenzophenone (Michler ketone), which will be described later. -Tetraalkyl-4,4'-diaminobenzophenone, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1,2-methyl-1- [4- (methylthio) phenyl] -2 Aromatic ketones such as morpholino-propanone-1; quinones fused with an aromatic ring such as alkylanthraquinone; benzoin ether compounds such as benzoin alkyl ether; benzoin compounds such as benzoin and alkylbenzoin; benzyl derivatives such as benzyldimethyl ketal Etc.
Among these, an oxime ester compound is preferable because it is excellent in sensitivity and gives a good pattern.

  From the viewpoint of obtaining good sensitivity and a remaining film ratio, the oxime ester compound is a compound represented by the following formula (b-1), a compound represented by the following formula (b-2), or the following formula (b It is preferable that it is a compound represented by -3).

In formula (22), R ₁₁ and R ₁₂ each represent an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 4 to 10 carbon atoms, a phenyl group, or a tolyl group, and an alkyl group having 1 to 8 carbon atoms, It is preferably a cycloalkyl group having 4 to 6 carbon atoms, a phenyl group or a tolyl group, more preferably an alkyl group having 1 to 4 carbon atoms, a cycloalkyl group having 4 to 6 carbon atoms, a phenyl group or a tolyl group. A methyl group, a cyclopentyl group, a phenyl group, or a tolyl group is more preferable.
R ₁₃ represents —H, —OH, —COOH, —O (CH ₂ ) OH, —O (CH ₂ ) ₂ OH, —COO (CH ₂ ) OH, or —COO (CH ₂ ) ₂ OH, _{-H, -O (CH 2) OH} , -O (CH 2) 2 OH, -COO (CH 2) OH, or -COO _{(CH 2)} is preferably from 2 OH, -H, -O (CH ₂ ) ₂ OH or —COO (CH ₂ ) ₂ OH is more preferable.

In formula (23), R < ₁₄ > shows a C1-C6 alkyl group, respectively, and it is preferable that it is a propyl group.
R ₁₅ represents NO ₂ or ArCO (wherein Ar represents an aryl group), and Ar is preferably a tolyl group.
R ₁₆ and R ₁₇ each represents an alkyl group having 1 to 12 carbon atoms, a phenyl group, or a tolyl group, and is preferably a methyl group, a phenyl group, or a tolyl group.

（式（２４）中、Ｒ_１８は、炭素数１〜６のアルキル基を示し、エチル基であることが好ましい。
Ｒ_１９はアセタール結合を有する有機基であり、後述する式（２４−１）に示す化合物が有するＲ_１９に対応する置換基であることが好ましい。
Ｒ_２０及びＲ_２１は、それぞれ炭素数１〜１２のアルキル基、フェニル基又はトリル基を示し、メチル基、フェニル基又はトリル基であることが好ましく、メチル基であることがより好ましい。

(In formula (24), R ₁₈ represents an alkyl group having 1 to 6 carbon atoms, and is preferably an ethyl group.
R ₁₉ is an organic group having an acetal bond, and is preferably a substituent corresponding to R ₁₉ included in the compound represented by formula (24-1) described later.
R ₂₀ and R ₂₁ each represent an alkyl group having 1 to 12 carbon atoms, a phenyl group, or a tolyl group, preferably a methyl group, a phenyl group, or a tolyl group, and more preferably a methyl group.

Examples of the compound represented by the formula (22) include a compound represented by the following formula (22-1) and a compound represented by the following formula (22-2). The compound represented by the following formula (22-1) is available as IRGACURE OXE-01 (trade name, manufactured by BASF Corporation).

Examples of the compound represented by the formula (23) include a compound represented by the following formula (23-1). This compound is available as DFI-091 (trade name, manufactured by Daito Chemix Co., Ltd.).

Examples of the compound represented by the formula (24) include a compound represented by the following formula (24-1). It is available as Adekaoptomer N-1919 (manufactured by ADEKA, trade name).

これら活性光線の照射によってラジカルを発生する化合物は、単独で用いてもよいし、２種以上を組み合わせて用いてもよい。 As other oxime ester compounds, the following compounds are preferably used.

These compounds that generate radicals upon irradiation with actinic rays may be used alone or in combination of two or more.

  As content of the compound which generate | occur | produces a radical by irradiation of actinic light, it is preferable that it is 0.01-10 weight part with respect to 100 weight part of (a) polyimide precursor, 0.01-5 weight part is preferable. More preferably, it is more preferably 0.05 to 3 parts by weight. When the blending amount is 0.01 parts by weight or more, crosslinking of the exposed part proceeds more sufficiently, and the photosensitive properties (sensitivity, resolution) of the composition tend to be better, and when it is 10 parts by weight or less. The heat resistance of the cured film obtained can be made better.

[Compound represented by Formula (c-1)]
The compound represented by the formula (c-1) as the component (c) can be used without particular limitation as long as it is an organic silane compound containing an organic group having an epoxy group or an organic group having a dihydroxyethylamino group. Specifically, γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, bis (2-hydroxyethyl) -3- Aminopropyl-triethoxysilane is mentioned. Among these, bis (2-hydroxyethyl) -3-aminopropyl-triethoxysilane is preferable.

  As content of the said compound, 0.1-20 mass parts is preferable with respect to 100 mass parts of (a) component, 1-10 mass parts is more preferable, and 1-3 are more preferable. When it is 0.1 part by mass or more, sufficient adhesion to the substrate can be imparted, and when it is 20 parts by mass or less, problems such as an increase in viscosity during storage at room temperature can be further suppressed.

[solvent]
The solvent that is component (d) is preferably a polar solvent that completely dissolves the polyimide precursor that is component (a). Examples of the polar solvent include N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, dimethyl sulfoxide, tetramethylurea, hexamethylphosphoric triamide, γ-butyrolactone, δ-valerolactone, γ-valerolactone, cyclohexanone, cyclopentanone, propylene glycol monomethyl ether acetate, propylene carbonate, ethyl lactate, 1,3-dimethyl-2-imidazolidinone and the like. These may be used alone or in combination of two or more.

  The content of the solvent is preferably 40 to 80% by mass, more preferably 45 to 75% by mass, and still more preferably 45 to 70% by mass in the photosensitive resin composition.

  The photosensitive resin composition of the present invention comprises (a) a polyimide precursor, (b) a compound that generates radicals upon irradiation with actinic rays, (c) a compound represented by formula (c-1), and (d) A solvent may be included, and the following other components may be further included.

The photosensitive resin composition of the present invention may contain (e) an organosilane compound other than the compound represented by (c-1) in order to improve adhesion to a cured silicon substrate or the like.
Organic silane compounds include γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, vinyltriethoxysilane, vinyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, and γ-glycidoxypropyltrimethoxy. Silane, γ-methacryloxypropyltrimethoxysilane, γ-acryloxypropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, bis (2-hydroxyethyl) ) -3-Aminopropyltriethoxysilane, triethoxysilylpropylethylcarbamate, 3- (triethoxysilyl) propyl succinic anhydride, phenyltriethoxysilane, phenyltrimethoxy Silane, N-phenyl-3-aminopropyltrimethoxysilane, 3-triethoxysilyl-N- (1,3-dimethylbutylidene) propylamine, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, tri And ethoxysilylpropylethyl carbamate, 3- [2- (3-triethoxysilylpropoxy) ethoxy] sulfolane, and the like. These may be used singly or in combination of two or more.
Among these, from the viewpoint of using together with the compound represented by the above (c-1) when adhesion after curing is required in addition to adhesion at the time of development, 3-ureidopropyltriethoxysilane, 3- Methacryloxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, triethoxysilylpropylethylcarbamate, or 3- [2- (3-triethoxysilylpropoxy) ethoxy] sulfolane is preferred.

  In the case where the photosensitive resin composition contains (e) an organosilane compound, the content of the organosilane compound is 0.1 to 20 with respect to 100 parts by weight of the polyimide precursor from the viewpoint of adhesion after curing. It is preferable to set it as a weight part, It is more preferable to set it as 0.5-15 weight part, It is further more preferable to set it as 0.5-10 weight part.

The photosensitive resin composition of the present invention may contain an (f) addition polymerizable compound as required.
Examples of the addition polymerizable compound include diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, trimethylolpropane di (meth) acrylate, trimethylolpropane tri (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, styrene, divinylbenzene, 4-vinyltoluene, 4-vinylpyridine, N-vinylpyrrolidone, 2-hydroxyethyl (meth) acrylate, 1,3- (meth) acryloyloxy-2-hydroxypropane, methylenebisacrylamide, , N- dimethyl acrylamide, N- methylol acrylamide.
These addition polymerizable compounds may be used alone or in combination of two or more.

  When the photosensitive resin composition contains an addition polymerizable compound, the content of the addition polymerizable compound is 100 parts by weight of the polyimide precursor from the viewpoint of solubility in a developer and heat resistance of the resulting cured film. On the other hand, it is preferably 1 to 100 parts by weight, more preferably 1 to 75 parts by weight, and still more preferably 1 to 50 parts by weight.

In order to ensure good storage stability, the photosensitive resin composition of the present invention may contain (g) a radical polymerization inhibitor or a radical polymerization inhibitor.
As radical polymerization inhibitors or radical polymerization inhibitors, p-methoxyphenol, diphenyl-p-benzoquinone, benzoquinone, hydroquinone, pyrogallol, phenothiazine, resorcinol, orthodinitrobenzene, paradinitrobenzene, metadinitrobenzene, phenanthraquinone, N- Examples include phenyl-2-naphthylamine, cuperone, 2,5-toluquinone, tannic acid, parabenzylaminophenol, nitrosamines and the like. These may be used alone or in combination of two or more.

  In the case where the photosensitive resin composition contains a radical polymerization inhibitor or a radical polymerization inhibitor, the content of the radical polymerization inhibitor or the radical polymerization inhibitor depends on the storage stability of the photosensitive resin composition and the cured film obtained. From the viewpoint of heat resistance, it is preferably 0.01 to 30 parts by weight, more preferably 0.01 to 10 parts by weight, and 0.05 to 5 parts by weight with respect to 100 parts by weight of the polyimide precursor. More preferably.

  When the photosensitive resin composition of the present invention is used on a copper substrate, the photosensitive resin composition preferably contains (h) tetrazole or a tetrazole derivative, or benzotriazole or a benzotriazole derivative.

When the photosensitive resin composition of the present invention is used on a copper substrate (for example, the rewiring layer 6 in FIG. 1 described later), the composition is an oxime ester compound (for example, IRGACURE OXE-) represented by the formula (22). 01 (made by BASF Corporation, trade name)), a polyimide residue may be formed in the opening when the pattern cured film is formed. About this cause, the present inventors presume that on a copper substrate, a specific oxime ester compound produces a radical at the time of pre-baking, and also hardens an unexposed part. In order to solve this problem, it is preferable to include the component (h) in the photosensitive resin composition. When (h) component is contained, it can suppress that a polyimide residue arises in an opening part.
Although the detailed mechanism for achieving the effect is not clear, the (h) component forms a thin film on the copper substrate and prevents the active metal surface and the resin composition from coming into direct contact with each other. It is presumed that the necessary photoinitiator decomposition and radical polymerization reaction were suppressed, and it was possible to ensure the photosensitive properties on the copper substrate.

As tetrazole and tetrazole derivatives, 1H-tetrazole, 5-methyl-1H-tetrazole, 5-phenyl-1H-tetrazole, 5-amino-1H-tetrazole, 1-methyl-1H-tetrazole, 5,5′-bis- 1H-tetrazole, 1-methyl-5-ethyl-tetrazole, 1-methyl-5-mercapto-tetrazole, 1-carboxymethyl-5-mercapto-tetrazole and the like can be mentioned.
Among these, 1H-tetrazole or 5-amino-1H-tetrazole is preferable.

Examples of benzotriazole and benzotriazole derivatives include benzotriazole, 1H-benzotriazole-1-acetonitrile, benzotriazole-5-carboxylic acid, 1H-benzotriazole-1-methanol, carboxybenzotriazole, mercaptobenzoxazole, and the like.
Among these, benzotriazole is preferable.

(H) A component may be used independently and may be used in combination of 2 or more types.
These are usually 0.1 to 10 parts by weight per one type with respect to 100 parts by weight of component (a), and in a combination of two or more types, the total amount is 0.1 to 10 parts by weight. More preferably, it is 0.2-5 weight part. If the amount is less than 0.1 part by weight, the effect of improving the adhesion to the metal layer tends to decrease.

The photosensitive resin composition of the present invention may contain at least one selected from components (a) to (d) and optionally components (e) to (h), and may be substantially composed of these components. Well, it may consist only of these components.
The term “substantially” means, for example, that the total amount of components (a) to (d) and components (e) to (h) in the photosensitive resin composition is 95% by weight or more, 97 It means that it is more than wt%, more than 98 wt%, or more than 99 wt%.

[Curing film]
A cured film is obtained by heat-treating the photosensitive resin composition of the present invention to advance the polyimide precursor into a polyimide.
As heating temperature which converts a polyimide precursor into a polyimide, 80-450 degreeC is preferable, 100-450 degreeC is more preferable, and it is more preferable that it is 200-400 degreeC. If it is less than 80 ° C., imidization does not proceed sufficiently and heat resistance may be lowered, and if heat treatment is performed at a temperature higher than 450 ° C., there is a possibility that a polyimide obtained by curing is deteriorated.

  The residual stress of the cured film obtained by curing the photosensitive resin composition of the present invention is preferably 30 MPa or less, more preferably 27 MPa or less, and further preferably 25 MPa or less. When the resulting cured film has a residual stress of more than 30 MPa, when the cured film is formed thick so that the film thickness after curing is 10 μm, the warpage of the wafer becomes large, and there is a problem in transporting and fixing the wafer. May occur.

σ：残留応力（Ｐａ）
Ｅ／（１−ν）：シリコンウェハーの二軸弾性係数（Ｐａ）
ｈ：シリコンウェハーの厚さ（ｍ）
ｔ：ポリイミド膜厚（ｍ）
Ｒ：シリコンウェハーの曲率半径の変化量（ｍ） The residual stress of the cured film can be calculated from the following formula (I) using the amount of change in the radius of curvature of the silicon wafer before and after the polyimide film is formed.
The radius of curvature of the silicon wafer is calculated from the reflection angle of the laser that scans the silicon wafer, and can be measured using a thin film stress measuring device (for example, FLX-2320 manufactured by KLA Tencor).

σ: Residual stress (Pa)
E / (1-ν): Biaxial elastic modulus of silicon wafer (Pa)
h: Silicon wafer thickness (m)
t: Polyimide film thickness (m)
R: Change amount of curvature radius of silicon wafer (m)

In order to form a cured film obtained by curing the photosensitive resin composition of the present invention so as to have a film thickness of 10 μm after curing, for example, the photosensitive resin composition film may be formed with a thickness of about 20 μm. .
When the film thickness of the polyimide precursor resin film obtained by applying and drying the photosensitive resin composition on the substrate is 20 μm, the i-line transmittance of the resin film is preferably 5% or more, and 8% or more. More preferably, it is more preferably 15% or more, and particularly preferably 30% or more. If the i-line transmittance is less than 5%, the i-line does not reach the deep part, and radicals are not sufficiently generated, so that the photosensitive characteristics may be deteriorated.
The i-ray transmittance can be measured by, for example, forming a resin film by applying and drying a polyimide precursor on a glass plate, and then measuring with an ultraviolet-visible spectrophotometer.

[Pattern cured film]
The cured pattern film of the present invention can be obtained by exposing and heating the photosensitive resin composition of the present invention. The patterned cured film of the present invention is preferably used as a protective layer of a Low-K material that is an interlayer insulating film. Examples of the Low-K material include porous silica, benzocyclobutene, hydrogen silsesquioxane, polyallyl ether, and the like.

  The method for producing a cured pattern film of the present invention includes a step of applying the photosensitive resin composition of the present invention on a substrate and drying to form a coating film, and irradiating the formed coating film with an actinic ray to expose the pattern. A step of removing an unexposed portion other than the exposed portion by development to obtain a pattern resin film, and a step of heat-treating the pattern resin film.

In the step of applying a photosensitive resin composition containing a polyimide precursor onto a substrate and drying to form a coating film, the method of applying the photosensitive resin composition onto the substrate includes dipping, spraying, and screening. Examples thereof include a printing method and a spin coating method.
Examples of the substrate include a silicon wafer, a metal substrate, and a ceramic substrate. Since the photosensitive resin composition containing the polyimide precursor of the present invention can form a low stress cured film, it is particularly suitable for application to a silicon wafer having a large diameter of 12 inches or more.

After the photosensitive resin composition is applied on the substrate, the solvent is removed (dried) by heating to form a coating film (resin film) with less adhesiveness.
In addition, it is preferable that the heating temperature at the time of drying is 80-130 degreeC, and it is preferable that drying time is 30-300 second. Drying is preferably performed using an apparatus such as a hot plate.

In the step of irradiating the coating film with an actinic ray to expose it in a pattern, and the step of removing the unexposed portion other than the exposed portion by development to obtain a patterned resin film, the pattern exposure is performed on the obtained coating film. Then, actinic rays are irradiated through a mask on which a desired pattern is drawn.
Although the photosensitive resin composition of the present invention is suitable for i-line exposure, ultraviolet rays, far ultraviolet rays, visible rays, electron beams, X-rays and the like can be used as the active rays to be irradiated.

A desired pattern can be obtained by dissolving and removing the unexposed portion with an appropriate developer after exposure.
Although there is no restriction | limiting in particular as a developing solution, Flame retardant solvent, such as 1,1,1-trichloroethane; Alkaline aqueous solution, such as sodium carbonate aqueous solution and tetramethylammonium hydroxide aqueous solution; N, N- dimethylformamide, dimethylsulfoxide, Good solvents such as N, N-dimethylacetamide, N-methyl-2-pyrrolidone, cyclopentanone, γ-butyrolactone, and acetates; and these good solvents and poor solvents such as lower alcohols, water, and aromatic hydrocarbons A mixed solvent or the like is used. After development, rinsing with a poor solvent (for example, water, ethanol, 2-propanol) or the like is performed as necessary.

In the step of heat-treating the pattern resin film, the resulting pattern resin film is heated, for example, at 80 to 400 ° C. for 5 to 300 minutes to advance imidization of the polyimide precursor contained in the photosensitive resin composition. A cured pattern film can be obtained.
In order to suppress the oxidative deterioration of the polyimide during heating, it is preferable to use a curing furnace that can be cured at a low oxygen concentration of 100 ppm or less, for example, an inert gas oven or a vertical diffusion furnace. Can do.

[Usage example of cured film or patterned cured film]
The cured film or pattern cured film of the present invention can be used as a surface protective layer, an interlayer insulating layer, a rewiring layer, or the like of a semiconductor device. Examples of the semiconductor device include logic semiconductors such as MPU and memory semiconductors such as DRAM and NAND flash.

  FIG. 1 is a schematic cross-sectional view of a semiconductor device having a rewiring structure according to an embodiment of the present invention. The semiconductor device of this embodiment has a multilayer wiring structure. An Al wiring layer 2 is formed on the interlayer insulating layer (interlayer insulating film) 1, and an insulating layer (insulating film) 3 (for example, a P-SiN layer) is further formed on the Al wiring layer 2. A (surface protective film) 4 is formed. A rewiring layer 6 is formed from the pad portion 5 of the wiring layer 2 and extends to an upper portion of the core 8 which is a connection portion with the conductive ball 7 formed of solder, gold or the like as an external connection terminal. Further, a cover coat layer 9 is formed on the surface protective layer 4. The rewiring layer 6 is connected to the conductive ball 7 through the barrier metal 10, and a collar 11 is provided to hold the conductive ball 7. When a package having such a structure is mounted, an underfill 12 may be interposed in order to further relieve stress.

  The cured film or pattern cured film of the present invention can be used for so-called packaging applications such as the cover coating material, the core material for rewiring, the color material for balls such as solder, the underfill material, and the like.

  EXAMPLES Hereinafter, although this invention is demonstrated in detail using an Example and a comparative example, this invention is not limited to these Examples.

[Synthesis of polyamic acid ester]
Pyromellitic dianhydride (PMDA) 17.45 g (80 mmol), 2-hydroxyethyl methacrylate (HEMA) 20.82 g (160 mmol), and catalytic amount of DBU (1,8-diazabicyclo [5.4.0]) Undeca-7-ene) was dissolved in 4 times the amount of pyromellitic dianhydride in N-methyl-2-pyrrolidone and stirred at room temperature for 48 hours to obtain an ester solution 1.
Further, 6.20 g (20 mmol) of 4,4′-oxydiphthalic anhydride (ODPA), 5.21 g (40 mmol) of 2-hydroxyethyl methacrylate (HEMA), and a catalytic amount of DBU were converted into 4,4′-oxydiphthalate. It melt | dissolved in 4 times amount N-methyl-2-pyrrolidone of an acid anhydride (ODPA), and it stirred at room temperature for 48 hours, and obtained the ester solution 2.

After mixing the ester solution 1 and the ester solution 2, while cooling in an ice bath, 2. with respect to the total amount of pyromellitic dianhydride (PMDA) and 4,4′-oxydiphthalic anhydride (ODPA). After 2 equivalents of thionyl chloride was added dropwise, the mixture was stirred for 1 hour to prepare an acid chloride solution.
Separately, 32.02 g (100 mmol) of 2,2′-bis (trifluoromethyl) benzidine (TFDB) and pyridine equivalent to twice the amount of thionyl chloride were added four times as much as 2,2′-bis (trifluoromethyl) benzidine. A solution dissolved in N-methyl-2-pyrrolidone was prepared and added dropwise to the previously prepared acid chloride solution while cooling in an ice bath.

  After completion of dropping, the reaction solution was dropped into distilled water, and the resulting precipitate was collected by filtration, washed twice with distilled water, and then vacuum dried to obtain a polyamic acid ester. The weight average molecular weight of the obtained polymer (polyamic acid ester) was 36000.

The weight average molecular weight of the obtained polyamic acid was calculated | required by standard polystyrene conversion by the gel permeation chromatography (GPC) method. Specifically, it measured by GPC method on the following measuring conditions using the solution [THF / DMF = 1/1 (volume ratio)] 1ml with respect to 0.5 mg of polyamic acids.
Measuring device: Detector L4000 UV manufactured by Hitachi, Ltd.
Pump: Hitachi Ltd. L6000
C-R4A Chromatopac manufactured by Shimadzu Corporation
Measurement conditions: Column Gelpack GL-S300MDT-5 × 2 eluent: THF / DMF = 1/1 (volume ratio)
LiBr (0.03 mol / l), H ₃ PO ₄ (0.06 mol / l)
Flow rate: 1.0 ml / min
Detector: UV270nm

Example 1-13 and Comparative Example 1-6
As shown below, a photosensitive resin composition was prepared using the materials shown in Table 1, a pattern cured film was produced using the obtained photosensitive resin composition, and the residual stress was evaluated. Moreover, the adhesiveness after the development after pattern opening, the resolution, the adhesiveness after curing, and the room temperature storage stability were evaluated.

[Preparation of resin composition]
(A) Component, (b) Component, (c) Component, (e) Component, and (h) Component in parts by mass shown in Table 1 and tetraethylene glycol dimethacrylate (addition polymerizable compound, TEGDMA) 20 After stirring a mass part until it melt | dissolved uniformly in 138 g of N-methyl-2-pyrrolidone, the photosensitive resin composition was obtained by carrying out pressure filtration using the filter with a hole diameter of 3 micrometers.

Each component in Table 1 is shown below.
[Component (b)]
b1: 1,2-octanedione, 1- [4- (phenylthio) phenyl-, 2- (O-benzoyloxime)] (IRGACURE OXE-01 manufactured by BASF)
b2: Compound represented by the formula (22-2) described above

[Component (c)]
KBM403: 3-glycidyloxypropyltrimethoxysilane (manufactured by Shin-Etsu Silicone)

KBM303: 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane (manufactured by Shin-Etsu Silicone)

SIB-1140.0: Bis (2-hydroxyethyl) -3-aminopropyltriethoxysilane (manufactured by Gelest)

ＳＩＴ８１８６．０：３−[２−（３−トリエトキシシリルプロポキシ）エトキシ]スルホラン（Ｇｅｌｅｓｔ社製）

[(E) component]
UTC801: 3-Ureidopropyltriethoxysilane KBM1003: Vinyltrimethoxysilane (manufactured by Shin-Etsu Silicone)
KBM503: 3-methacryloxypropyltrimethoxysilane (manufactured by Shin-Etsu Silicone)
KBM803: 3-mercaptopropyltrimethoxysilane (manufactured by Shin-Etsu Silicone)
SIT8188.0: Triethoxysilylpropyl ethyl carbamate (manufactured by Gelest)

SIT8186.0: 3- [2- (3-Triethoxysilylpropoxy) ethoxy] sulfolane (manufactured by Gelest)

[(H) component]
BT: Benzotriazole

  Table 1 shows the results of evaluating the residual stress, resolution, room temperature storage stability, and adhesion of the cured film for the resin compositions prepared in Examples and Comparative Examples. The evaluation method is as follows.

(1) Evaluation of photosensitive property (resolution) The obtained resin composition was applied on a 6-inch silicon wafer by a spin coating method and dried on a hot plate at 100 ° C. for 3 minutes to form a coating film having a thickness of 10 μm. Formed. This coating film was exposed to light by irradiating a predetermined pattern with an exposure amount of 300 mJ / cm ² in terms of i-line using an i-line stepper FPA-3000iW (manufactured by Canon Inc.) through a photomask. Also, the development time is set to twice the time until an unexposed coating film of the same thickness is immersed in cyclopentanone and completely dissolved, and the wafer after exposure is immersed in cyclopentanone and paddle developed. Thereafter, rinsing with propylene glycol monomethyl ether acetate was performed. At this time, the minimum value of the mask dimension of the square hole-shaped opening was evaluated as the resolution. A sample having a resolution of 10 μm or less was designated A, a sample having a resolution greater than 10 μm and 15 μm or less was designated B, and a sample having a resolution greater than 15 μm was designated C.

(2) Evaluation of residual stress The resin composition was applied to a 6-inch silicon wafer having a thickness of 625 μm and spin-coated so that the film thickness after curing was 10 μm. This was heat-cured at 270 ° C. for 4 hours in a nitrogen atmosphere using a vertical diffusion furnace (manufactured by Koyo Lindberg) to obtain a polyimide film. The residual stress of the cured polyimide film was measured at room temperature using a thin film stress measuring apparatus FLX-2320 (manufactured by KLA Tencor). A stress was 30 MPa or less as A, 30 MPa and 35 MPa or less as B, and 35 MPa or more as C.

(3) Evaluation of room temperature storage stability The obtained resin composition was applied onto a 6-inch silicon wafer by spin coating, and heated on a hot plate at 100 ° C. for 3 minutes to form a 15 μm coating film. The film thickness was measured. The film thickness at this time was defined as the initial film thickness. In order to evaluate the room temperature storage stability of the resin composition, the film thickness was measured in the same manner using the resin composition stored at room temperature (25 ° C.) for 1 week. This film thickness was defined as the film thickness after storage for 1 week.
The case where the rate of change of the film thickness was 0.5% or less of the initial film thickness was A, the case where it was 0.5% or more and 2% or less was B, and the case where the film thickness changed 2% or more was C.

(4) Evaluation of adhesion after development The obtained resin composition was applied on a 6-inch silicon wafer by a spin coating method, and heated on a hot plate at 100 ° C. for 3 minutes to form a 15 μm coating film. In order to confirm the adhesion after development between the polyimide film and the silicon wafer used as the substrate, the adhesion was examined by a cross-cut test method (JIS K5400-8.5 (JIS D0202)).
The case where 50 squares or more of the polyimide film remained on the substrate was A, the case where only 50 squares or less remained was B, and the case where the film did not remain on the substrate was designated C.

(5) Evaluation of adhesion after curing The obtained resin composition was applied on a 6-inch silicon wafer by spin coating so that the film thickness after curing was 10 μm, and heated on a hot plate at 100 ° C. for 3 minutes. A coating film was formed. This was heated and cured at 270 ° C. for 4 hours in a nitrogen atmosphere using a vertical diffusion furnace (manufactured by Koyo Lindberg) to obtain a polyimide film (cured film). In order to confirm the adhesion between the polyimide film and the silicon wafer used as the substrate, the adhesion was examined by a cross-cut test method (JIS K5400-8.5 (JIS D0202)). The case where there was no peeling was set to 100, and the case where all peeled was set to 0.
In addition, after the polyimide film is exposed to conditions of 121 ° C., 2 atm, and 100% RH for a predetermined time (100 hours and 200 hours), the polyimide film is adhered again by a cross-cut test method (JIS K5400-8.5 (JIS D0202)). I examined the sex.

  By using the component (c) for the photosensitive resin composition showing a low stress value, the developed film has excellent adhesion to the substrate, and the cured film is obtained by using the component (e). The adhesiveness of is improved. Furthermore, it was found that by using the component (c) and the component (e) in combination, excellent adhesion was obtained after development and after curing.

  The resin composition of the present invention can be used as a protective film material or a pattern film forming material for electronic parts such as semiconductor devices.

DESCRIPTION OF SYMBOLS 1 Interlayer insulating layer 2 Al wiring layer 3 Insulating layer 4 Surface protection layer 5 Pad part of wiring layer 6 Rewiring layer 7 Conductive ball 8 Core 9 Cover coat layer 10 Barrier metal 11 Color 12 Underfill

Claims (11)

A photosensitive resin composition containing the following components (a) to (d).
(A) Polyimide precursor having a structural unit represented by the following formula (1) (b) Compound that generates radicals upon irradiation with actinic rays (c) Compound represented by the following formula (c-1) (d) Solvent

(In Formula (1), A is either the tetravalent organic group represented by following formula (2).
B is a divalent organic group represented by the following formula (3).
R ¹ and R ² are each independently a hydrogen atom or a monovalent organic group. )

(In Formula (2), X and Y each independently represent a divalent group or a single bond that is not conjugated to the benzene ring to which each is bonded.)

(In Formula (3), at least one of R ^{3 to} R ¹⁰ is a fluorine atom, a trifluoromethyl group, or a methyl group, and the other is a hydrogen atom.)

(In the formula (c-1),
R ¹¹ is each independently an alkyl group having 1 to 4 carbon atoms.
R < ¹² > is respectively independently a hydroxyl group or a C1-C4 alkyl group.
a is an integer of 1 to 3.
n is an integer of 1-6.
R ¹³ is an organic group having an epoxy group or an organic group having a dihydroxyethylamino group. ) The photosensitive resin composition according to claim 1, wherein the component (a) is a polyimide precursor having a structural unit represented by the following formula (4).

(In formula (4), D is a tetravalent organic group represented by the following general formula (5).
B, R ¹ and R ² are the same as those in the formula (1), respectively. )

(In Formula (5), Z is an oxygen atom or a sulfur atom.)   The photosensitive resin composition according to claim 2, wherein the molar ratio of the formula (1) to the formula (4) is 5/5 to 9/1. The photosensitive resin composition according to claim 1, wherein R ¹ or R ^{2 in} the formula (1) is a monovalent organic group having a carbon-carbon unsaturated double bond.   The photosensitive resin composition in any one of Claims 1-4 containing a tetrazole, a tetrazole derivative, a benzotriazole, or a benzotriazole derivative.   The photosensitive resin composition according to claim 1, wherein the component (b) is an oxime ester compound. The photosensitivity according to claim 6, wherein the oxime ester compound is a compound represented by the following formula (22), a compound represented by the following formula (23), or a compound represented by the following general formula (24). Resin composition.

(In the formula _{(22), R 11} and _{R 12} are each an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 4 to 10 carbon atoms, a phenyl group or a tolyl group.
R ₁₃ is —H, —OH, —COOH, —O (CH ₂ ) OH, —O (CH ₂ ) ₂ OH, —COO (CH ₂ ) OH, or —COO (CH ₂ ) ₂ OH. )

(In Formula (23), R < ₁₄ > is a C1-C6 alkyl group, respectively.
R ₁₅ is NO ₂ or ArCO (Ar is an aryl group).
R ₁₆ and R ₁₇ are each an alkyl group having 1 to 12 carbon atoms, a phenyl group, or a tolyl group. )

(In the formula _{(24), R 18} is an alkyl group having 1 to 6 carbon atoms.
R ₁₉ is an organic group having an acetal bond.
R ₂₀ and R ₂₁ are each an alkyl group having 1 to 12 carbon atoms, a phenyl group, or a tolyl group. )   3-ureidopropyltriethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, triethoxysilylpropylethylcarbamate, or 3- [2- (3-triethoxysilylpropoxy) ethoxy] sulfolane The photosensitive resin composition in any one of Claims 1-7 to contain.   The pattern cured film obtained by heating the photosensitive resin composition in any one of Claims 1-8. Applying the photosensitive resin composition according to claim 1 on a substrate and drying to form a coating film;
Irradiating an actinic ray to the formed coating film and exposing it in a pattern,
A method for producing a patterned cured film, comprising: removing a non-exposed portion other than the exposed portion by development to obtain a patterned resin film; and heating the pattern resin film.   The semiconductor device which has a pattern cured film obtained with the manufacturing method of the pattern cured film of Claim 10.

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