WO2018207294A1 - Positive-type photosensitive resin composition, thermal crosslinking agent for positive-type photosensitive resins, patterned cured film and method for producing same, semiconductor element, and electronic device - Google Patents

Abstract

Disclosed is a positive-type photosensitive resin composition containing (A) an alkali-soluble resin, (B) a compound represented by general formula (1) or a compound represented by general formula (2), and (C) a compound having at least two epoxy groups. [In general formula (1), R¹ to R⁶ independently represent an alkyl group having 1 to 10 carbon atoms.] [In general formula (2), R⁷ to R¹² independently represent an alkyl group having 1 to 10 carbon atoms.]

Description

Positive photosensitive resin composition, thermal crosslinking agent for positive photosensitive resin, patterned cured film and method for producing the same, semiconductor element, and electronic device

The present invention relates to a positive photosensitive resin composition, a thermal crosslinking agent for positive photosensitive resin, a pattern cured film and a method for producing the same, a semiconductor element, and an electronic device.

In recent years, as semiconductor elements have been highly integrated and miniaturized, insulating layers such as interlayer insulating layers and surface protective layers of semiconductor elements have better heat resistance (thermal expansion coefficient, etc.) and mechanical properties (breaking strength, breaking elongation). Etc.). A positive photosensitive resin composition containing an alkali-soluble resin has been developed as a material for forming an insulating layer having such characteristics (see, for example, Patent Documents 1, 2, and 3). These positive photosensitive resin compositions are applied onto a substrate and dried to form a resin film, and the resin film is exposed and developed to obtain a patterned resin film (patterned resin film). A patterned cured film (patterned cured film) can be formed by heat curing the patterned resin film, and the patterned cured film can be used as an insulating layer. In addition, these photosensitive resin compositions have an advantage that they can be cured by heating at a low temperature in the step of forming the pattern cured film.

JP 2008-309885 A JP 2007-057595 A International Publication No. 2010/073948

By the way, in the semiconductor element, as the wafer is downsized and the insulating layer is multilayered, the warpage of the package due to the residual stress of the pattern cured film used for the insulating layer becomes a problem. Therefore, the material used is required to reduce the residual stress of the formed pattern cured film.

Generally, in order to reduce the residual stress of a cured film, it is considered effective to reduce the crosslinking density of the cured film. However, when the crosslinking density is lowered, the film strength tends to decrease at the same time, and the chemical resistance of the pattern cured film tends to decrease.

The present invention has been made in view of such circumstances, and is a positive photosensitive resin composition capable of forming a cured film having low residual stress, excellent chemical resistance, and excellent adhesion to a substrate. The main purpose is to provide goods.

As a result of diligent studies to achieve the above object, the present inventors have found that, in combination with a specific compound in the positive photosensitive resin composition, a cured film having low residual stress and excellent chemical resistance can be formed. I found it. Furthermore, the obtained cured film was found to have excellent adhesion to the substrate, and the present invention was completed.

One aspect of the present invention includes (A) an alkali-soluble resin, (B) a compound represented by the following general formula (1) or a compound represented by the following general formula (2), and (C) two or more Provided is a positive photosensitive resin composition containing an epoxy group-containing compound. According to such a positive photosensitive resin composition, it is possible to form a patterned cured film having low residual stress, excellent chemical resistance, and excellent adhesion to the substrate.

[In the general formula (1), R ¹ to R ⁶ each independently represents an alkyl group having 1 to 10 carbon atoms. ]

[In the general formula (2), R ⁷ to R ¹² each independently represents an alkyl group having 1 to 10 carbon atoms. ]

The molar ratio of the component (C) to the component (B) may be 1.0 or less. When the molar ratio is in such a range, chemical resistance and breaking strength tend to be more excellent.

The component (C) may be a compound having an aromatic ring or a heterocyclic ring. Further, the component (C) may be a compound represented by the following general formula (3). When the component (C) is such a compound, the chemical resistance of the formed pattern cured film tends to be more excellent.

[In the general formula (3), R ¹³ to R ¹⁵ each independently represents an alkylene group having 1 to 10 carbon atoms. ]

The positive photosensitive resin composition may further contain (D) an elastomer. The positive photosensitive resin composition may further contain (E) a compound that generates an acid by light. By using these components, the heat resistance (coefficient of thermal expansion) and mechanical properties (breaking strength and breaking elongation) of the formed pattern cured film tend to be excellent.

In another aspect, a thermal crosslinking agent for a positive photosensitive resin comprising a compound represented by the following general formula (1) or a compound represented by the following general formula (2), and a compound having two or more epoxy groups I will provide a. Using such a thermal crosslinking agent for a positive photosensitive resin, a positive photosensitive resin composition capable of forming a cured pattern film having low residual stress, excellent chemical resistance, and excellent adhesion to a substrate Can be easily prepared.

[In the general formula (1), R ¹ to R ⁶ each independently represents an alkyl group having 1 to 10 carbon atoms. ]

[In the general formula (2), R ⁷ to R ¹² each independently represents an alkyl group having 1 to 10 carbon atoms. ]

In another aspect, there is provided a pattern cured film having a pattern, wherein the pattern includes a cured product of a resin film made of the positive photosensitive resin composition described above.

In another aspect, a step of applying and drying the positive photosensitive resin composition to a part or the whole of the substrate to form a resin film, a step of exposing a part or the whole of the resin film, and a step after the exposure A method for producing a cured pattern film comprising: a step of developing the resin film with an alkaline aqueous solution to form a pattern resin film; and a step of heating the pattern resin film.

In another aspect, there is provided a semiconductor device comprising the above-described pattern cured film as an interlayer insulating layer or a surface protective layer.

In another aspect, an electronic device comprising the above semiconductor element is provided.

According to the present invention, it is possible to provide a positive photosensitive resin composition capable of forming a cured film having low residual stress, excellent chemical resistance, and excellent adhesion to a substrate. Moreover, the thermal crosslinking agent for positive photosensitive resins which can prepare such a positive photosensitive resin composition easily can be provided. Furthermore, the pattern cured film using such a positive photosensitive resin composition, its manufacturing method, a semiconductor element, and an electronic device can be provided.

It is the schematic perspective view and schematic end view explaining one Embodiment of the manufacturing process of a semiconductor element. It is the schematic perspective view and schematic end view explaining one Embodiment of the manufacturing process of a semiconductor element. It is the schematic perspective view and schematic end view explaining one Embodiment of the manufacturing process of a semiconductor element. It is the schematic perspective view and schematic end view explaining one Embodiment of the manufacturing process of a semiconductor element. It is the schematic perspective view and schematic end view explaining one Embodiment of the manufacturing process of a semiconductor element. It is a schematic sectional drawing which shows one Embodiment of a semiconductor element. It is a schematic sectional drawing which shows one Embodiment of a semiconductor element.

Hereinafter, embodiments of the present invention will be described in detail. However, the present invention is not limited to the following embodiments.

In the present specification, “(meth) acrylic acid” means “acrylic acid” or “methacrylic acid”, and the same applies to other similar expressions such as (meth) acrylate.

[Positive photosensitive resin composition]
The positive photosensitive resin composition of one embodiment includes (A) an alkali-soluble resin, (B) a compound represented by the general formula (1) or a compound represented by the general formula (2), and (C) And a compound having two or more epoxy groups.

<(A) component>
The component (A) is a resin that is soluble in an alkaline aqueous solution (developer). The alkaline aqueous solution is an alkaline solution such as a tetramethylammonium hydroxide (TMAH) aqueous solution, a metal hydroxide aqueous solution, or an organic amine aqueous solution. In general, an aqueous tetramethylammonium hydroxide solution having a concentration of 2.38% by mass is used for development.

It can be confirmed, for example, as follows that the component (A) is soluble in an alkali developer.

A varnish obtained by dissolving the component (A) in an arbitrary solvent is spin-coated on a substrate such as a silicon wafer to form a coating film having a thickness of about 5 μm. This is immersed in either a TMAH aqueous solution, a metal hydroxide aqueous solution or an organic amine aqueous solution at 20 to 25 ° C. As a result, when the coating film can be dissolved uniformly, the component (A) can be regarded as soluble in an alkaline developer.

Examples of the component (A) include polyester resins, polyether resins, polyimide resins, polyamide resins, polyamideimide resins, polyetherimide resins, polyurethane resins, polyurethaneimide resins, polyurethaneamideimide resins, siloxane polyimide resins, and polyesterimide resins. , Polybenzoxazole resin, phenoxy resin, polysulfone resin, polyethersulfone resin, polyphenylene sulfide resin, polycarbonate resin, polyether ketone resin, (meth) acrylic copolymer, resin having a phenolic hydroxyl group, and the like. These can be used alone or in combination of two or more. In addition, the main chain or side chain of these resins may be provided with a glycol group such as ethylene glycol or propylene glycol, a carboxyl group, or a hydroxyl group.

Among these, the component (A) is preferably a resin having a phenolic hydroxyl group from the viewpoint of high-temperature adhesiveness, heat resistance, and film formability.

As the resin having a phenolic hydroxyl group, for example, polyhydroxystyrene or a hydroxystyrene-based resin such as a copolymer containing hydroxystyrene as a monomer unit, a phenol resin, a polybenzoxazole precursor such as poly (hydroxyamide), Examples include poly (hydroxyphenylene) ether and polynaphthol. The component (A) may be composed of only one of these resins, or may be composed of two or more.

Among these, (A1) hydroxystyrene-based resin is preferable because of its excellent electrical properties (insulating properties) and small volume shrinkage during curing. In addition, (A2) a phenol resin is preferable, and a novolac type phenol resin is more preferable because it is inexpensive, has high contrast, and has a small volume shrinkage at the time of curing.

(A1) The hydroxystyrene-based resin has a structural unit represented by the following general formula (21).

In the general formula (21), R ²¹ represents a hydrogen atom or a methyl group, R ²² represents an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms, a represents an integer of 0 to 3, and b represents an integer of 1 to 3. The sum of a and b is 5 or less.

(A1) The hydroxystyrene-based resin can be obtained by polymerizing a monomer or the like that gives the structural unit represented by the general formula (21).

In the general formula (21), examples of the alkyl group having 1 to 10 carbon atoms represented by R ²¹ include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, and a nonyl group. Group, decyl group and the like. These groups may be linear or branched. Examples of the aryl group having 6 to 10 carbon atoms represented by R ²² include a phenyl group and a naphthyl group. Examples of the alkoxy group having 1 to 10 carbon atoms represented by R ²¹ include methoxy group, ethoxy group, propoxy group, butoxy group, pentoxy group, hexoxy group, heptoxy group, octoxy group, nonoxy group, and decoxy group. It is done. These groups may be linear or branched.

Monomers that give the structural unit represented by the general formula (21) include, for example, p-hydroxystyrene, m-hydroxystyrene, o-hydroxystyrene, p-isopropenylphenol, m-isopropenylphenol, o-isopropenyl. Phenol etc. are mentioned. These monomers can be used singly or in combination of two or more.

(A1) Hydroxystyrene resin is not limited by its production method. For example, the hydroxyl group of the monomer that gives the structural unit represented by the general formula (21) is protected by a t-butyl group, an acetyl group, etc. The resulting monomer is polymerized with a hydroxyl group-protected monomer to obtain a polymer, and the resulting polymer is converted to a hydroxystyrene structural unit by deprotection under an acid catalyst. Etc.) can be obtained by deprotection.

(A1) The hydroxystyrene-based resin may be a polymer or copolymer consisting only of a monomer that gives the structural unit represented by the general formula (21), and the structural unit represented by the general formula (21) It may be a copolymer of the monomer to be given and other monomers. (A1) When the hydroxystyrene-based resin is a copolymer, the proportion of the structural unit represented by the general formula (21) in the copolymer is (A) from the viewpoint of solubility in an alkaline developer in the exposed area. 10 to 100 mol% is preferable, 20 to 97 mol% is more preferable, 30 to 95 mol% is further preferable, and 50 to 95 mol% is particularly preferable with respect to 100 mol% of the component.

(A1) The hydroxystyrene-based resin is preferably an alkali-soluble resin further having a structural unit represented by the following general formula (22) from the viewpoint of further improving the dissolution inhibition of the unexposed portion with respect to the alkaline developer. .

In the general formula (22), R ²³ represents a hydrogen atom or a methyl group, R ²⁴ represents an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms, c represents an integer of 0 to 3.

Examples of the alkyl group having 1 to 10 carbon atoms, the aryl group having 6 to 10 carbon atoms or the alkoxy group having 1 to 10 carbon atoms represented by R ²⁴ are the same as those for R ²² .

The alkali-soluble resin having the structural unit represented by the general formula (22) can be obtained by using a monomer that gives the structural unit represented by the general formula (22). Monomers that give the structural unit represented by the general formula (22) include, for example, styrene, α-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, o-methoxystyrene, and m-methoxystyrene. And aromatic vinyl compounds such as p-methoxystyrene. These monomers can be used singly or in combination of two or more.

(A1) When the hydroxystyrene-based resin is an alkali-soluble resin having a structural unit represented by the general formula (22), from the viewpoint of dissolution inhibition with respect to an alkaline developer in an unexposed area and mechanical properties of a pattern cured film, The proportion of the structural unit represented by the formula (22) is preferably 1 to 90 mol%, more preferably 3 to 80 mol%, still more preferably 5 to 70 mol%, relative to 100 mol% of the component (A). ˜50 mol% is particularly preferred.

Further, the (A1) hydroxystyrene-based resin is preferably an alkali-soluble resin having a structural unit represented by the following general formula (23) from the viewpoint of lowering the elastic modulus.

In general formula (23), R ²⁵ represents a hydrogen atom or a methyl group, and R ²⁶ represents an alkyl group having 1 to 10 carbon atoms or a hydroxyalkyl group having 1 to 10 carbon atoms.

The alkali-soluble resin having the structural unit represented by the general formula (23) can be obtained by using a monomer that gives the structural unit represented by the general formula (23). Monomers that give the structural unit represented by the general formula (23) include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, (meth) Pentyl acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate, hydroxymethyl (meth) acrylate, (meth) Hydroxyethyl acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, hydroxypentyl (meth) acrylate, hydroxyhexyl (meth) acrylate, hydroxyheptyl (meth) acrylate, (meth) acrylic acid Hydroxyoctyl, hydroxynonyl (meth) acrylate (Meth) hydroxy decyl acrylate and the like. These monomers can be used singly or in combination of two or more.

(A1) When the hydroxystyrene-based resin is an alkali-soluble resin having a structural unit represented by the general formula (23), from the viewpoints of dissolution inhibition with respect to an alkali developer in an unexposed area and mechanical properties of the pattern cured film, The proportion of the structural unit represented by the formula (23) is preferably 1 to 90 mol%, more preferably 3 to 80 mol%, still more preferably 5 to 70 mol%, relative to 100 mol% of the component (A). ˜50 mol% is particularly preferred.

(A2) The phenol resin is a polycondensation product of phenol or a derivative thereof and aldehydes. The polycondensation is usually performed in the presence of a catalyst such as an acid or a base. The phenol resin obtained when an acid catalyst is used is particularly called a novolak type phenol resin. Examples of the novolak type phenol resin include phenol / formaldehyde novolak resin, cresol / formaldehyde novolak resin, xylenol / formaldehyde novolak resin, resorcinol / formaldehyde novolak resin, phenol-naphthol / formaldehyde novolak resin, and the like.

(A2) Examples of the phenol derivative constituting the phenol resin include o-cresol, m-cresol, p-cresol, o-ethylphenol, m-ethylphenol, p-ethylphenol, o-butylphenol, m-butylphenol, p-butylphenol, 2,3-xylenol, 2,4-xylenol, 2,5-xylenol, 2,6-xylenol, 3,4-xylenol, 3,5-xylenol, 2,3,5-trimethylphenol, 3 , 4,5-trimethylphenol and other alkylphenols, methoxyphenol and 2-methoxy-4-methylphenol and other alkoxyphenols, vinylphenol and allylphenol and other alkenylphenols, benzylphenol and other aralkylphenols and methoxycal Alkylcarbonylphenol such as nylphenol, arylcarbonylphenol such as benzoyloxyphenol, halogenated phenol such as chlorophenol, polyhydroxybenzene such as catechol, resorcinol, pyrogallol, bisphenol such as bisphenol A and bisphenol F, α- or β- Naphthol derivatives such as naphthol, hydroxyalkylphenols such as p-hydroxyphenyl-2-ethanol, p-hydroxyphenyl-3-propanol, p-hydroxyphenyl-4-butanol, hydroxyalkylcresols such as hydroxyethylcresol, monoethylene of bisphenol Alcoholic hydroxyl group-containing phenol derivatives such as oxide adducts and monopropylene oxide adducts of bisphenol Carboxyl group-containing phenol derivatives such as p-hydroxyphenylacetic acid, p-hydroxyphenylpropionic acid, p-hydroxyphenylbutanoic acid, p-hydroxycinnamic acid, hydroxybenzoic acid, hydroxyphenylbenzoic acid, hydroxyphenoxybenzoic acid and diphenolic acid Etc. These can be used individually by 1 type or in combination of 2 or more types.

(A2) Examples of aldehydes constituting the phenol resin include formaldehyde, acetaldehyde, furfural, benzaldehyde, hydroxybenzaldehyde, methoxybenzaldehyde, hydroxyphenylacetaldehyde, methoxyphenylacetaldehyde, crotonaldehyde, chloroacetaldehyde, chlorophenylacetaldehyde, glyceraldehyde, Examples include glyoxylic acid, methyl glyoxylate, phenyl glyoxylate, hydroxyphenyl glyoxylate, formyl acetic acid, methyl formyl acetate, 2-formylpropionic acid, methyl 2-formylpropionate, and the like. These can be used individually by 1 type or in combination of 2 or more types. In addition, formaldehyde precursors such as paraformaldehyde and trioxane, and ketones such as acetone, pyruvic acid, levulinic acid, 4-acetylbutyric acid, acetonedicarboxylic acid, and 3,3′-4,4′-benzophenonetetracarboxylic acid You may use for reaction.

When the component (A) contains (A1) hydroxystyrene-based resin or (A2) phenol resin, the weight average molecular weight of each of the component (A1) and the component (A2) is solubility in an aqueous alkali solution, photosensitive characteristics, and pattern. Considering the balance of mechanical properties of the cured film, the weight average molecular weight is preferably from 1,000 to 500,000, more preferably from 2,000 to 200,000, and further preferably from 2,000 to 100,000. Here, the weight average molecular weight is a value obtained by measuring by a gel permeation chromatography (GPC) method and converting from a standard polystyrene calibration curve.

<(B) component>
The compound as the component (B) is a compound having a structure that can react with the component (A) to form a bridge structure when the photosensitive resin film after pattern formation is cured by heating. The component (B) is a compound represented by the following general formula (1) or a compound represented by the following general formula (2).

In general formula (1), R ¹ to R ⁶ each independently represents an alkyl group having 1 to 10 carbon atoms.

Examples of the alkyl group having 1 to 10 carbon atoms represented by R ¹ to R ⁶ are the same as those for R ²² . The alkyl group preferably has 1 to 5 carbon atoms, more preferably 1 to 3, more preferably 1 or 2, and particularly preferably 1.

In the general formula (2), R ⁷ to R ¹² each independently represents an alkyl group having 1 to 10 carbon atoms.

Examples of the alkyl group having 1 to 10 carbon atoms represented by R ⁷ to R ¹² are the same as those for R ²² . The alkyl group preferably has 1 to 5 carbon atoms, more preferably 1 to 3, more preferably 1 or 2, and particularly preferably 1.

<(C) component>
When the compound as the component (C) has two or more epoxy groups and is cured by heating the photosensitive resin film after pattern formation together with the compound as the component (B) described above, the component (A) It is a compound having a structure capable of reacting with and forming a bridge structure.

The component (C) can be used without particular limitation as long as it has two or more epoxy groups. Examples of the component (C) include aliphatic epoxy compounds, aromatic epoxy compounds, alicyclic epoxy compounds, heterocyclic epoxy compounds, bisphenol type epoxy compounds, novolac type epoxy compounds, glycidylamine type epoxy compounds, and halogenated epoxies. Compounds and the like. These can be used individually by 1 type or in combination of 2 or more types.

Among these, the component (C) is preferably an epoxy compound having an aromatic ring or a heterocyclic ring, more preferably an epoxy compound having a heterocyclic ring, from the viewpoint of superior chemical resistance, and a nitrogen-containing heterocyclic ring. More preferably, it is an epoxy compound.

The component (C) is preferably a compound represented by the following general formula (3) from the viewpoint of superior chemical resistance.

In the general formula (3), R ¹³ to R ¹⁵ each independently represents an alkylene group having 1 to 10 carbon atoms.

In the general formula (3), examples of the alkylene group having 1 to 10 carbon atoms represented by R ¹³ to R ¹⁵ include a methylene group, an ethylene group, a propylene group, a butylene group, a pentylene group, a hexylene group, a heptylene group, and an octylene group. Group, nonylene group, decylene group and the like. These groups may be linear or branched. The alkylene group preferably has 1 to 8 carbon atoms, and more preferably 1 to 6 carbon atoms.

The molar ratio of the component (C) to the component (B) (number of moles of the component (C) / number of moles of the component (B)) is 1.0 or less from the viewpoint of better resistance to chemicals and breaking strength. It is preferably 9 or less, and more preferably 0.8 or less. Although the minimum of the molar ratio of (C) component with respect to (B) component is not restrict | limited, 0.1 or more, 0.2 or more, or 0.3 or more may be sufficient.

The total amount of the component (B) and the component (C) is preferably 2 to 35 parts by mass with respect to 100 parts by mass of the component (A) from the viewpoint of being excellent in residual stress and chemical resistance. More preferably, it is 5 to 25 parts by mass.

In addition to the components (A) to (C), the positive photosensitive resin composition of the present embodiment may further contain (D) an elastomer or (E) a compound that generates an acid by light. By using these components, a positive photosensitive resin composition excellent in breaking strength and thermal expansibility can be obtained.

<(D) component>
Examples of the elastomer include styrene-based elastomer, olefin-based elastomer, urethane-based elastomer, polyester-based elastomer, polyamide-based elastomer, acrylic-based elastomer, and silicone-based elastomer. These can be used individually by 1 type or in combination of 2 or more types. Among these, the component (D) may be an acrylic elastomer because it is excellent in breaking strength, breaking elongation, and thermal expansibility of the obtained pattern cured film.

The acrylic elastomer preferably has a structural unit represented by the following general formula (31).

In the general formula (31), R ³¹ represents a hydrogen atom or a methyl group, and R ³² represents a hydroxyalkyl group having 2 to 20 carbon atoms.

Examples of the hydroxyalkyl group having 2 to 20 carbon atoms represented by R ³² include a hydroxyethyl group, a hydroxypropyl group, a hydroxybutyl group, a hydroxypentyl group, a hydroxyhexyl group, a hydroxyheptyl group, a hydroxyoctyl group, and a hydroxynonyl group. , Hydroxydecyl group, hydroxyundecyl group, hydroxydodecyl group (sometimes referred to as hydroxylauryl group), hydroxytridecyl group, hydroxytetradecyl group, hydroxypentadecyl group, hydroxyhexadecyl group, hydroxyheptadecyl group, hydroxy An octadecyl group, a hydroxy nonadecyl group, a hydroxyeicosyl group, etc. are mentioned.

The acrylic elastomer further has a structural unit represented by the following general formula (32), a structural unit represented by the following general formula (33), or a structural unit represented by the following general formula (34). Also good.

In General Formula (32), R ³³ represents a hydrogen atom or a methyl group, and R ³⁴ represents a monovalent organic group having a primary, secondary, or tertiary amino group.

Examples of the primary, secondary or tertiary amino group represented by R ³⁴ include an aminoethyl group, an N-methylaminoethyl group, an N, N-dimethylaminoethyl group, an N-ethylaminoethyl group, an N, N -Diethylaminoethyl group, aminopropyl group, N-methylaminopropyl group, N, N-dimethylaminopropyl group, N-ethylaminopropyl group, N, N-diethylaminopropyl group, piperidin-4-yl group, 1-methyl Piperidin-4-yl group, 2,2,6,6-tetramethylpiperidin-4-yl group, 1,2,2,6,6-pentamethylpiperidin-4-yl group, (piperidin-4-yl) Examples thereof include a methyl group and 2- (piperidin-4-yl) ethyl group.

In general formula (33), R ³⁵ represents a hydrogen atom or a methyl group, and R ³⁶ represents an alkyl group having 4 to 20 carbon atoms.

Examples of the alkyl group having 4 to 20 carbon atoms represented by R ³⁶ include a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, an undecyl group, and a dodecyl group (also referred to as a lauryl group). And tridecyl group, tetradecyl group, pentadecyl group, hexadecyl group, heptadecyl group, octadecyl group, nonadecyl group, eicosyl group and the like. These groups may be linear or branched.

In the general formula (34), R ³⁷ represents a hydrogen atom or a methyl group.

The acrylic elastomer includes, for example, a monomer that gives the structural unit represented by the general formula (31), and a structural unit represented by the general formula (32), (33), or (34) that is added as necessary. Can be obtained by blending a monomer that gives water, stirring in a solvent such as ethyl lactate, toluene, isopropanol, and heating as necessary.

The weight average molecular weight of the acrylic elastomer is preferably from 2,000 to 100,000, more preferably from 3,000 to 60,000, still more preferably from 5,000 to 50,000, and particularly preferably from 10,000 to 40,000. Here, the weight average molecular weight is a value obtained by measuring by a gel permeation chromatography (GPC) method and converting from a standard polystyrene calibration curve.

The content of the component (D) is preferably 1 to 35 parts by mass, preferably 3 to 30 parts by mass with respect to 100 parts by mass of the component (A), from the viewpoint of being superior in breaking strength and elongation at break. More preferred is 5 to 25 parts by mass.

<(E) component>
The compound which produces | generates an acid by the light which is (E) component (by receiving light) functions as a photosensitive agent in the photosensitive resin composition. The component (E) has a function of generating acid upon irradiation with light and further increasing the solubility of the irradiated portion in an alkaline aqueous solution. As the component (E), a compound generally called a photoacid generator can be used. Specific examples of the component (E) include o-quinonediazide compounds, aryldiazonium salts, diaryliodonium salts, triarylsulfonium salts, and the like. (E) A component may consist only of 1 type in these compounds, and may be comprised including 2 or more types. Of these, o-quinonediazide compounds are preferred because of their high sensitivity.

As the o-quinonediazide compound, for example, a compound obtained by subjecting o-quinonediazidesulfonyl chloride and a hydroxy compound or an amino compound to a condensation reaction in the presence of a dehydrochlorinating agent can be used.

The o-quinonediazide compound includes 1,1-bis (4-hydroxyphenyl) -1- [4- {1- (4-hydroxyphenyl) -1-methylethyl} phenyl] ethane and 1-naphthoquinone-2-diazide- It is preferable to use a condensate with 5-sulfonyl chloride, a condensate of tris (4-hydroxyphenyl) methane or tris (4-hydroxyphenyl) ethane with 1-naphthoquinone-2-diazide-5-sulfonyl chloride.

The content of the component (E) is 5 to 25 parts by mass with respect to 100 parts by mass of the component (A) from the viewpoint that the difference in dissolution rate between the exposed part and the unexposed part becomes larger and the sensitivity becomes better. It is preferably 6 to 20 parts by mass, more preferably 7 to 18 parts by mass.

<Other ingredients>
In addition to the components (A) to (E), the positive photosensitive resin composition of the present embodiment includes a solvent, a compound that generates an acid upon heating, a dissolution accelerator, a dissolution inhibitor, a coupling agent, and a surfactant. And may contain components such as a leveling agent.

(solvent)
By using a solvent, coating on a substrate can be facilitated and a coating film having a uniform thickness can be formed. Examples of the solvent include γ-butyrolactone, ethyl lactate, propylene glycol monomethyl ether acetate, benzyl acetate, n-butyl acetate, ethoxyethyl propionate, 3-methylmethoxypropionate, N-methyl-2-pyrrolidone, N , N-dimethylformamide, N, N-dimethylacetamide, dimethyl sulfoxide, hexamethylphosphorylamide, tetramethylene sulfone, diethyl ketone, diisobutyl ketone, methyl amyl ketone, cyclohexanone, propylene glycol monomethyl ether, propylene glycol monopropyl ether, propylene glycol Examples thereof include monobutyl ether and dipropylene glycol monomethyl ether. These solvents can be used alone or in combination of two or more. Among these, ethyl lactate or propylene glycol monomethyl ether acetate is preferable from the viewpoints of solubility and coating film uniformity.

(Compound that generates acid by heating)
By using a compound that generates an acid by heating, it becomes possible to generate an acid when the pattern resin film is heated. Therefore, a reaction between the component (A), the component (B), and the component (C), that is, The thermal crosslinking reaction is promoted, and the heat resistance of the pattern cured film is improved. Moreover, since the compound which produces | generates an acid by heating generate | occur | produces an acid also by light irradiation, the solubility to the alkaline aqueous solution of an exposure part increases. Therefore, the difference in solubility in the alkaline aqueous solution between the unexposed area and the exposed area is further increased and the resolution is further improved.

Examples of the compound that generates an acid by such heating include those that generate an acid by heating to 50 to 250 ° C., for example. Specific examples of the compound that generates an acid by heating include a salt formed from a strong acid such as an onium salt and a base, imide sulfonate, and the like.

(Dissolution promoter)
By using a dissolution accelerator, it is possible to increase the dissolution rate of the exposed area when developing with an alkaline aqueous solution, and to improve sensitivity and resolution. A conventionally well-known thing can be used as a dissolution promoter. Specific examples thereof include compounds having a carboxyl group, a sulfonic acid, and a sulfonamide group.

Further, the dissolution accelerator may be a phenolic low molecular compound represented by any one of the following general formulas (41) to (43).

In the general formula (41), R ⁴¹ represents a hydrogen atom or a methyl group. a1 to f1 represent integers of 0 to 3, the sum of d1 to f1 is 1 or more, the sum of a1 and d1 is 5 or less, the sum of b1 and e1 is 5 or less, and the sum of c1 and f1 Is 5 or less.

In general formula (42), ^R42 represents a hydrogen atom or a methyl group. a2 to c2 represent integers of 0 to 3, d2 to f2 represent integers of 1 to 3, the sum of a2 and d2 is 5 or less, the sum of b2 and e2 is 5 or less, and c2 and f2 The total is 5 or less.

In general formula (43), a3, c3, h and i represent integers of 0 to 3, d3 and f3 represent integers of 1 to 3, and the sum of a3 and d3 is 5 or less. The sum is 5 or less, and the sum of h and i is 4 or less.

(Dissolution inhibitor)
The dissolution inhibitor is a compound that inhibits the dissolution of the component (A) in an alkaline aqueous solution, and is used to control the remaining film thickness, development time, and contrast. Examples of the dissolution inhibitor include diphenyliodonium nitrate, bis (p-tert-butylphenyl) iodonium nitrate, diphenyliodonium bromide, diphenyliodonium chloride, diphenyliodonium iodide, and the like.

(Coupling agent)
By using a coupling agent, the adhesiveness between the pattern cured film to be formed and the substrate can be further enhanced. Examples of the coupling agent include organic silane compounds and aluminum chelate compounds.

(Surfactant, leveling agent)
By using a surfactant or a leveling agent, applicability can be further improved. Specifically, for example, by containing a surfactant or a leveling agent, striation (film thickness unevenness) can be further prevented, and developability can be further improved. Examples of the surfactant or leveling agent include polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, polyoxyethylene octylphenol ether, and the like.

The content when other components are used may be 0.01 to 20 parts by mass with respect to 100 parts by mass of component (A).

According to the positive photosensitive resin composition of the present embodiment, it is possible to form a cured pattern film having low residual stress, excellent chemical resistance, and excellent adhesion to the substrate.

[Thermal crosslinking agent for positive photosensitive resin]
The thermal crosslinking agent for positive photosensitive resin of one embodiment includes the above-described component (B) (the compound represented by the general formula (1) or the compound represented by the general formula (2)) and the component (C) ( A compound having two or more epoxy groups). According to such a thermal crosslinking agent for a positive photosensitive resin, a positive photosensitive resin composition capable of forming a pattern cured film having low residual stress, excellent chemical resistance, and excellent adhesion to a substrate. Can be easily prepared.

[Pattern cured film and manufacturing method thereof]
The pattern cured film of one embodiment has a pattern, and the pattern includes a cured product of a resin film made of the above-described positive photosensitive resin composition. The pattern cured film can be obtained by heating the positive photosensitive resin composition described above. Hereinafter, the manufacturing method of a pattern cured film is demonstrated.

The pattern cured film manufacturing method of the present embodiment includes a step of applying and drying the positive photosensitive resin composition described above on a part or all of a substrate to form a resin film (application / drying (film formation) step); , A step of exposing part or all of the resin film (exposure step), a step of developing the exposed resin film with an alkaline aqueous solution to form a pattern resin film (development step), and a step of heating the pattern resin film (Heat treatment process). Hereinafter, each step will be described.

<Application / drying (film formation) process>
First, the positive photosensitive resin composition of this embodiment is applied onto a substrate and dried to form a resin film. In this step, the positive photosensitive resin composition of the present embodiment is used on a glass substrate, a semiconductor, a metal oxide insulator (for example, TiO ₂ , SiO _2, etc.), silicon nitride, or the like using a spinner or the like. And spin coat to form a coating film. The thickness of the coating film is not particularly limited, but is preferably 0.1 to 40 μm. The substrate on which this coating film has been formed is dried using a hot plate, oven, or the like. There is no particular limitation on the drying temperature and drying time, but it is preferably performed at 80 to 140 ° C. for 1 to 7 minutes. Thereby, a resin film is formed on the support substrate. The thickness of the resin film is not particularly limited, but is preferably 0.1 to 40 μm.

<Exposure process>
Next, in the exposure step, the resin film formed on the substrate is irradiated with actinic rays such as ultraviolet rays, visible rays, and radiations through a mask. In the positive photosensitive resin composition of the present embodiment, since the component (A) has high transparency to i-line, i-line irradiation can be suitably used. In addition, post-exposure heating (PEB) can also be performed after exposure from a viewpoint of improving a dissolution rate as needed. In the case of performing post-exposure heating, the temperature is preferably 70 to 140 ° C., and the post-exposure heating time is preferably 1 to 5 minutes.

<Development process>
In the development step, the exposed portion of the resin film after the exposure step is removed with a developer, whereby the resin film is patterned and a patterned resin film is obtained. As the developer, for example, an alkaline aqueous solution such as sodium carbonate, sodium hydroxide, potassium hydroxide, sodium silicate, ammonia, ethylamine, diethylamine, triethylamine, triethanolamine, tetramethylammonium hydroxide (TMAH) is preferably used. It is done. The base concentration of these aqueous solutions is preferably 0.1 to 10% by mass. Furthermore, an alcohol or a surfactant can be added to the developer. Each of these can be blended in an amount of preferably 0.01 to 10 parts by mass, more preferably 0.1 to 5 parts by mass with respect to 100 parts by mass of the developer. When development is performed using a developer, the developer is placed on the resin film by a method such as shower development, spray development, immersion development, paddle development, and the like, and the conditions are 18 to 40 ° C., and 30 to 360. Leave for seconds. After leaving, the pattern resin film is washed by washing with water and spin drying.

<Heat treatment process>
Next, in the heat treatment step, the pattern cured film can be formed by heat treating the pattern resin film. The heating temperature in the heat treatment step is preferably 250 ° C. or less and more preferably 230 ° C. or less from the viewpoint of sufficiently preventing damage to the semiconductor device due to heat.

The heat treatment can be performed, for example, using an oven such as a quartz tube furnace, a hot plate, rapid thermal annealing, a vertical diffusion furnace, an infrared curing furnace, an electron beam curing furnace, a microwave curing furnace. In addition, either air or an inert atmosphere such as nitrogen can be selected. However, it is preferable to perform the process under nitrogen because the oxidation of the pattern can be prevented. Since the above-mentioned preferable heating temperature range is lower than the conventional heating temperature, damage to the support substrate and the semiconductor device can be reduced. Therefore, electronic devices can be manufactured with a high yield by using the resist pattern manufacturing method of the present embodiment. It also leads to energy savings in the process. Furthermore, according to the positive photosensitive resin composition of the present embodiment, the volumetric shrinkage (curing shrinkage) in the heat treatment step found in photosensitive polyimide or the like is small, so that a reduction in dimensional accuracy can be prevented.

The heat treatment time in the heat treatment step may be a time sufficient for the positive photosensitive resin composition to cure, but is preferably 5 hours or less in view of work efficiency.

The heat treatment can also be performed using a microwave curing device or a variable frequency microwave curing device in addition to the above-described oven. By using these devices, it is possible to effectively heat only the photosensitive resin film while keeping the temperature of the substrate and the semiconductor device at, for example, 200 ° C. or less (J. Photopolym. Sci. Technol., 18, 327-332 (2005)).

According to the method for producing a cured pattern film of the present embodiment described above, a cured pattern film having sufficiently high sensitivity and resolution, and excellent adhesion and thermal shock properties can be obtained.

[Interlayer insulation layer, surface protective layer]
The pattern cured film of this embodiment can be used as an interlayer insulating layer or a surface protective layer of a semiconductor element.

[Semiconductor element]
The semiconductor element of one embodiment includes the interlayer insulating layer or the surface protective layer of this embodiment. The semiconductor element of the present embodiment is not particularly limited, but means a memory, a package, or the like having a multilayer wiring structure, a rewiring structure, or the like.

Here, an example of the manufacturing process of the semiconductor element will be described with reference to the drawings. 1 to 5 are a schematic perspective view and a schematic end view showing an embodiment of a manufacturing process of a semiconductor device having a multilayer wiring structure. 1 to 5, (a) is a schematic perspective view, and (b) is a schematic end view showing Ib-Ib to Vb-Vb end surfaces in (a), respectively.

First, the structure 100 shown in FIG. 1 is prepared. The structure 100 includes a semiconductor substrate 1 such as a Si substrate having circuit elements, a protective film 2 such as a silicon oxide film covering the semiconductor substrate 1 and having a predetermined pattern from which the circuit elements are exposed, and exposed circuit elements. A first conductor layer 3 formed thereon, and an interlayer insulating layer 4 made of polyimide resin or the like formed on the protective film 2 and the first conductor layer 3 by a spin coat method or the like are provided.

Next, by forming the photosensitive resin layer 5 having the window 6A on the interlayer insulating layer 4, the structure 200 shown in FIG. 2 is obtained. The photosensitive resin layer 5 is formed, for example, by applying a photosensitive resin such as chlorinated rubber, phenol novolac, polyhydroxystyrene, or polyacrylate ester by a spin coating method. The window 6A is formed so that a predetermined portion of the interlayer insulating layer 4 is exposed by a known photolithography technique.

After the interlayer insulating layer 4 is etched to form the window 6B, the photosensitive resin layer 5 is removed to obtain the structure 300 shown in FIG. For etching the interlayer insulating layer 4, dry etching means using a gas such as oxygen or carbon tetrafluoride can be used. By this etching, the portion of the interlayer insulating layer 4 corresponding to the window portion 6A is selectively removed, and the interlayer insulating layer 4 provided with the window portion 6B so that the first conductor layer 3 is exposed is obtained. Next, the photosensitive resin layer 5 is removed using an etching solution that corrodes only the photosensitive resin layer 5 without corroding the first conductor layer 3 exposed from the window 6B.

Further, the second conductor layer 7 is formed in a portion corresponding to the window portion 6B, and the structure 400 shown in FIG. 4 is obtained. A known photolithography technique can be used to form the second conductor layer 7. As a result, the second conductor layer 7 and the first conductor layer 3 are electrically connected.

Finally, the surface protective layer 8 is formed on the interlayer insulating layer 4 and the second conductor layer 7 to obtain the semiconductor element 500 shown in FIG. In the present embodiment, the surface protective layer 8 is formed as follows. First, the photosensitive resin composition described above is applied onto the interlayer insulating layer 4 and the second conductor layer 7 by spin coating, and dried to form a photosensitive resin film. Next, after irradiating light through a mask on which a pattern corresponding to the window portion 6C is drawn at a predetermined portion, the exposed resin film is developed with an alkaline aqueous solution to form a patterned resin film. Thereafter, the pattern resin film used as the surface protective layer 8 is formed by curing the pattern resin film by heating. The surface protective layer 8 protects the first conductor layer 3 and the second conductor layer 7 from external stress, α rays, and the like, and the semiconductor element 500 using the surface protective layer 8 of the present embodiment is reliable. Excellent in properties.

In the above-described embodiment, a method for manufacturing a semiconductor device having a two-layer wiring structure has been described. However, when a multilayer wiring structure having three or more layers is formed, the above steps are repeated to form each layer. Can do. That is, it is possible to form a multilayer pattern by repeating each step of forming the interlayer insulating layer 4 and each step of forming the surface protective layer 8. In the above example, not only the surface protective layer 8 but also the interlayer insulating layer 4 can be formed using the photosensitive resin composition of the present embodiment.
The electronic device of the present embodiment is not limited to one having a surface protective layer, a cover coat layer, or an interlayer insulating layer formed using the positive photosensitive resin composition described above, and can have various structures.

6 and 7 are schematic cross-sectional views showing an embodiment of a semiconductor device having a rewiring structure. Since the photosensitive resin composition of this embodiment is excellent in stress relaxation property, adhesiveness, and the like, it can be used in a semiconductor element having a rewiring structure as shown in FIGS.

FIG. 6 is a schematic cross-sectional view showing a wiring structure as one embodiment of a semiconductor element. A semiconductor element 600 shown in FIG. 6 includes a silicon substrate 23, an interlayer insulating layer 11 provided on one side of the silicon substrate 23, and an Al having a pattern including a pad portion 15 formed on the interlayer insulating layer 11. A wiring layer 12, an insulating layer 13 (for example, a P-SiN layer) and a surface protective layer 14, which are sequentially stacked on the interlayer insulating layer 11 and the Al wiring layer 12 while forming an opening on the pad portion 15, and a surface; The island-shaped core 18 disposed in the vicinity of the opening on the protective layer 14 and the pad portion 15 in the opening of the insulating layer 13 and the surface protective layer 14, and on the surface opposite to the surface protective layer 14 of the core 18. And a rewiring layer 16 extending on the surface protective layer 14 so as to be in contact therewith. Furthermore, the semiconductor element 600 is formed so as to cover the surface protective layer 14, the core 18, and the rewiring layer 16, and a cover coat layer 19 in which an opening is formed in a portion of the rewiring layer 16 on the core 18. The conductive ball 17 connected to the rewiring layer 16 with the barrier metal 20 interposed therebetween in the opening of the layer 19, the collar 21 that holds the conductive ball, and the cover coat layer 19 around the conductive ball 17 are provided. The underfill 22 is provided. The conductive ball 17 is used as an external connection terminal and is formed of solder, gold or the like. The underfill 22 is provided to relieve stress when the semiconductor element 600 is mounted.

In the semiconductor element 700 of FIG. 7, an Al wiring layer (not shown) and an Al wiring layer pad portion 15 are formed on a silicon substrate 23, and an insulating layer 13 is formed on the Al wiring layer. A surface protective layer 14 is formed. A rewiring layer 16 is formed on the pad portion 15, and the rewiring layer 16 extends to an upper portion of the connection portion 24 with the conductive ball 17. Further, a cover coat layer 19 is formed on the surface protective layer 14. The rewiring layer 16 is connected to the conductive ball 17 through the barrier metal 20.

6 and 7, the photosensitive resin composition is a material for forming not only the interlayer insulating layer 11 and the surface protective layer 14, but also the cover coat layer 19, the core 18, the collar 21, the underfill 22, and the like. Can be used as Since the pattern cured film using the photosensitive resin composition of the present embodiment is excellent in adhesion with a metal layer such as the Al wiring layer 12 or the rewiring layer 16 or a sealing agent, and has a high stress relaxation effect, A semiconductor element in which a pattern cured film is used for an interlayer insulating layer 11, a surface protective layer 14, a cover coat layer 19, a core 18, a collar 21 such as solder, an underfill 22 used in a flip chip or the like is extremely excellent in reliability. It will be a thing.

The photosensitive resin composition of the present embodiment is preferably used for the interlayer insulating layer 11, the surface protective layer 14 or the cover coat layer 19 of the semiconductor element having the rewiring layer 16 in FIGS.

The film thickness of the interlayer insulating layer 11, the surface protective layer 14 and the cover coat layer 19 is preferably 3 to 20 μm, and more preferably 5 to 15 μm.

[Electronic device]
The electronic device of one embodiment has the semiconductor element of this embodiment. The electronic device includes the above-described semiconductor element, and examples thereof include a mobile phone, a smartphone, a tablet terminal, a personal computer, and a hard disk suspension.

Hereinafter, the present invention will be specifically described based on examples, but the present invention is not limited thereto.

The materials used in the examples are shown below.

[(A) component]
A1: Polymer of 4-hydroxystyrene (weight average molecular weight = 10000, manufactured by Maruzen Petrochemical Co., Ltd., trade name “Marcalinker M”)
A2: 4-hydroxystyrene / styrene = 85/15 (molar ratio) copolymer (weight average molecular weight = 10000, manufactured by Maruzen Petrochemical Co., Ltd., trade name “Marcalinker CST”)
A3: Copolymer of 4-hydroxystyrene / methyl methacrylate = 70/30 (molar ratio) (weight average molecular weight = 12000, manufactured by Maruzen Petrochemical Co., Ltd., trade name “Marcalinker CMM”)
A4: Cresol novolak resin (cresol / formaldehyde novolak resin, m-cresol / p-cresol (molar ratio) = 60/40, weight average molecular weight = 12000, manufactured by Asahi Organic Materials Co., Ltd., trade name “EP4020G”)

In addition, the weight average molecular weight was calculated | required by standard polystyrene conversion, respectively using the gel permeation chromatography (GPC) method.

Specifically, the weight average molecular weight was measured with the following apparatus and conditions.
measuring device:
Detector: L4000UV manufactured by Hitachi, Ltd.
Pump: Hitachi Ltd. L6000
Column: Gelpack GL-S300MDT-5 × 2 Measurement conditions:
Eluent: THF
LiBr (0.03 mol / l), H ₃ PO ₄ (0.06 mol / l)
Flow rate: 1.0 ml / min, detector: UV 270 nm
The measurement was performed using a solution of 1 ml of a solvent [THF / DMF = 1/1 (volume ratio)] with respect to 0.5 mg of the sample.

[Component (B)]
B1: Compound in which R ¹ to R ^{6 in} the general formula (1) are all methyl groups (hexakis (methoxymethyl) melamine, manufactured by Sanwa Chemical Co., Ltd., trade name “Nicalak MW-30HM”, molecular weight: 390.4)
B2: a compound in which R ⁷ to R ^{12 in} the general formula (2) are all methyl groups (manufactured by Honshu Chemical Industry Co., Ltd., trade name “HMOM-TPPA”, molecular weight 688.9)

[Component (C)]
C1: Trifunctional epoxy compound (a compound in which R ¹³ to R ^{15 in} the general formula (3) are all methylene groups, manufactured by Nissan Chemical Industries, Ltd., trade name “TEPIC-L”, molecular weight: 297.3)
C2: Trifunctional epoxy compound (a compound in which R ¹³ to R ^{15 in} the general formula (3) are all n-propylene groups, manufactured by Nissan Chemical Industries, Ltd., trade name “TEPIC-VL”, molecular weight: 381.4)
C3: Trifunctional epoxy compound (a compound in which R ¹³ to R ^{15 in} the general formula (3) are all n-hexylene groups, manufactured by Nissan Chemical Industries, Ltd., trade name “TEPIC-FL”, molecular weight: 507.7)
C4: Trifunctional epoxy compound (compound represented by the following formula (X), manufactured by Printec Co., Ltd., trade name “TECHMORE VG3101L”, molecular weight: 592.7)

C5: Bifunctional epoxy compound (polyethylene glycol # 400 diglycidyl ether, manufactured by Kyoeisha Chemical Co., Ltd., trade name “Epolite 400E”, molecular weight: 526.6)

[(D) component]
D1: 55 g of ethyl lactate was weighed into a 100 ml three-necked flask equipped with a stirrer, a nitrogen introducing tube and a thermometer, and separately weighed polymerizable monomer (n-butyl acrylate (BA) 34.7 g) Lauryl acrylate (LA) 2.2 g, acrylic acid (AA) 3.9 g, hydroxybutyl acrylate (HBA) 2.6 g, and 1,2,2,6,6-pentamethylpiperidin-4-yl methacrylate ( Product name: FA-711MM (manufactured by Hitachi Chemical Co., Ltd.) (1.7 g) and azobisisobutyronitrile (AIBN) (0.29 g) were added, and nitrogen gas was stirred while stirring at room temperature with a stirring speed of about 160 rpm. Was dissolved at a flow rate of 400 ml / min for 30 minutes to remove dissolved oxygen, and then the inflow of nitrogen gas was stopped, the flask was sealed, and the temperature was raised to 65 ° C. in a constant temperature water bath in about 25 minutes. The polymerization reaction was carried out while maintaining the same temperature for 10 hours to obtain an elastomer D1, in which the polymerization rate was 99%, and the weight average molecular weight of D1 was about 22000. The molar ratio of the polymerizable monomer in the elastomer D1 is as follows.
BA / LA / AA / HBA / FA-711MM = 70.5 / 2.5 / 20/5/2 (mol%)

In addition, the weight average molecular weight of (D) component was calculated | required by the method similar to the measurement of the weight average molecular weight of (A) component.

[(E) component]
E1: Compound represented by the following formula (Y) (manufactured by Daitokemix Co., Ltd., trade name “PA-28”)

(Examples 1 to 9 and Comparative Examples 1 to 3)
Ingredients (A) to (C) of the blending amounts (parts by mass) shown in Table 1 and 120 parts by mass of ethyl lactate as a solvent were blended, and this was subjected to pressure filtration using a Teflon (registered trademark) filter having 3 μm pores. The positive photosensitive resin compositions of Examples 1 to 9 and Comparative Examples 1 to 3 were prepared.

<Evaluation of positive photosensitive resin composition>
(Production of cured film)
The positive photosensitive resin compositions of Examples 1 to 9 and Comparative Examples 1 to 3 are spin-coated on a 6-inch silicon substrate and heated at 120 ° C. for 3 minutes to form a resin film having a thickness of about 12 to 14 μm. did. Thereafter, the resin film was heat-treated (cured) by the following method (i) to obtain a cured film having a thickness of about 10 μm.
(I) Using a vertical diffusion furnace (trade name “μ-TF” manufactured by Koyo Thermo Systems Co., Ltd.), the resin film was heat-treated in nitrogen at a temperature of 230 ° C. (temperature increase time: 1.5 hours) for 2 hours. .

(Chemical solution swelling rate)
On the cured film obtained in the above (preparation of cured film), flux (Senju Metal Industry Co., Ltd., trade name “WF-6300LF”) was applied as a chemical solution, and heat treatment was performed at 260 ° C. for 3 minutes. Later, the chemical solution was removed by washing with water. The thickness of the cured film was measured before and after the chemical treatment, and the chemical swelling rate was calculated from the following formula. A chemical | medical solution swelling rate means that it is so favorable that a numerical value is small (25% or less). The results are shown in Table 1.
Chemical solution swelling rate (%) = [(film thickness of cured film after chemical solution treatment) / (film thickness of cured film before chemical solution treatment) −1] × 100

(Residual stress)
The residual stress of the cured film obtained in the above (Preparation of cured film) was measured using a stress measuring device (FLX-2320, manufactured by KLA Tencor). The smaller the numerical value (20 MPa or less), the better the residual stress. The results are shown in Table 1.

(Al adhesion strength)
Spin the positive photosensitive resin compositions of Examples 1 to 9 and Comparative Examples 1 to 3 on a 6-inch aluminum substrate (a substrate on which Ti is sputter-formed on a silicon substrate and then aluminum is sputter-formed on the Ti substrate). The coated film was heated at 120 ° C. for 3 minutes to form a resin film having a film thickness of 11 to 13 μm. Thereafter, heat treatment (curing) was performed by the above method (i) to obtain a cured film having a thickness of about 10 μm. The cured film was cut into small pieces (1 cm × 1 cm) together with the substrate, and the aluminum stud and the cured film were bonded via an epoxy resin layer. Next, the stud was pulled and the load at the time of peeling was measured. The adhesion strength means that the larger the value (39.2 MPa (400 kgf / cm ² ) or more)), the better. The results are shown in Table 1.

As shown in Table 1, the positive photosensitive resin composition containing the component (B) and the component (C) is compared with the positive photosensitive resin composition not containing the component (B) and the component (C), In the obtained cured film, the residual stress was reduced, and the chemical solution resistance and the adhesion to the substrate were also excellent.

(Examples 10 and 11 and Comparative Examples 4 to 6)
Ingredients (A) to (E) in the blending amounts (parts by mass) shown in Table 2 and 120 parts by mass of ethyl lactate as a solvent were blended, and this was pressure filtered using a 3 μm pore Teflon (registered trademark) filter. The positive photosensitive resin compositions of Examples 10 and 11 and Comparative Examples 4 to 6 were prepared.

<Evaluation of positive photosensitive resin composition>
(Chemical swelling rate, residual stress, adhesion strength)
Evaluation was performed using the same method as described above. The results are shown in Table 2.

(Preparation of pattern cured film)
The positive photosensitive resin compositions of Examples 10 and 11 and Comparative Examples 4 to 6 were spin-coated on a 6 inch silicon substrate and heated at 120 ° C. for 3 minutes to form a resin film having a thickness of about 12 to 14 μm. did. Thereafter, this resin film was exposed using a proximity exposure machine (trade name “PLA-600FA”, manufactured by Canon Inc.) at an exposure amount twice the minimum exposure amount at all wavelengths through a mask. After the exposure, development was performed using a 2.38 mass% aqueous solution of TMAH (tetramethylammonium hydroxide) to obtain a 10 mm wide pattern resin film. Thereafter, the pattern resin film was heat-treated (cured) by the following method (i) to obtain a pattern cured film having a thickness of about 10 μm.
(I) Using a vertical diffusion furnace (trade name “μ-TF” manufactured by Koyo Thermo Systems Co., Ltd.), heat treatment is performed on the patterned resin film in nitrogen at a temperature of 230 ° C. (temperature increase time: 1.5 hours) for 2 hours. did.

(Breaking strength after hardening, elongation after hardening)
The breaking strength and breaking elongation of the obtained pattern cured film were measured using an autograph AGS-H100N (manufactured by Shimadzu Corporation). The sample width was 10 mm, the film thickness was 9 to 11 μm, and the gap between chucks was 20 mm. The pulling speed was 5 mm / min, and the measurement temperature was 20 ° C. to 25 ° C. The average of the measured values of five or more test pieces obtained from the cured pattern film obtained under the same conditions was defined as “breaking strength” and “breaking elongation”. A breaking strength means that it is so favorable that a numerical value is large (100 Mpa or more). Breaking elongation means that it is so favorable that a numerical value is large (30% or more). The results are shown in Table 2.

(CTE)
The average thermal expansion coefficient (CTE) at 50 to 150 ° C. of the cured film obtained by the same method as the above (preparation of patterned cured film) was measured using TMA / SS600 (manufactured by Seiko Instruments Inc.). The sample used for measurement was adjusted to have a width of 2 mm, a film thickness of about 10 μm, and a gap between chucks of 10 mm. The measurement conditions were a load of 10 g and a temperature increase rate of 5 ° C./min. CTE means that it is so favorable that a numerical value is low (70 ppm / K or less). The results are shown in Table 2.

As shown in Table 2, the positive photosensitive resin composition containing the component (B) and the component (C) and further containing the component (D) and the component (E) is composed of the component (B) and the component (C). Compared with a positive photosensitive resin composition containing no curable resin, residual stress was reduced in the resulting cured film, and the chemical resistance and adhesion to the substrate were excellent. Moreover, it turned out that the pattern cured film obtained is excellent also in breaking strength, breaking elongation, and a thermal expansion coefficient.

From the above, it was confirmed that the positive photosensitive resin composition of the present invention can form a cured film having low residual stress, excellent chemical resistance, and excellent adhesion to the substrate.

DESCRIPTION OF SYMBOLS 1 ... Semiconductor substrate, 2 ... Protective film, 3 ... 1st conductor layer, 4 ... Interlayer insulation layer, 5 ... Photosensitive resin layer, 6A, 6B, 6C ... Window part, 7 ... 2nd conductor layer, 8 ... Surface protection 11 ... Interlayer insulating layer, 12 ... Al wiring layer, 13 ... Insulating layer, 14 ... Surface protective layer, 15 ... Pad part, 16 ... Re-wiring layer, 17 ... Conductive ball, 18 ... Core, 19 ... Cover coat Layer, 20 ... barrier metal, 21 ... color, 22 ... underfill, 23 ... silicon substrate, 24 ... connecting portion, 100, 200, 300,400 ... structure, 500,600,700 ... semiconductor element.

Claims (11)

1. (A) an alkali-soluble resin;
   (B) a compound represented by the following general formula (1) or a compound represented by the following general formula (2);
   (C) a compound having two or more epoxy groups;
   A positive photosensitive resin composition comprising:
   

   

   [In the general formula (1), R ¹ to R ⁶ each independently represents an alkyl group having 1 to 10 carbon atoms. ]
   

   

   [In the general formula (2), R ⁷ to R ¹² each independently represents an alkyl group having 1 to 10 carbon atoms. ]
2. The positive photosensitive resin composition according to claim 1, wherein a molar ratio of the component (C) to the component (B) is 1.0 or less.
3. The positive photosensitive resin composition according to claim 1 or 2, wherein the component (C) is a compound having an aromatic ring or a heterocyclic ring.
4. The positive photosensitive resin composition according to any one of claims 1 to 3, wherein the component (C) is a compound represented by the following general formula (3).
   

   

   [In the general formula (3), R ¹³ to R ¹⁵ each independently represents an alkylene group having 1 to 10 carbon atoms. ]
5. The positive photosensitive resin composition according to any one of claims 1 to 4, further comprising (D) an elastomer.
6. (E) The positive photosensitive resin composition according to any one of claims 1 to 5, further comprising a compound that generates an acid by light.
7. A thermal crosslinking agent for a positive photosensitive resin comprising a compound represented by the following general formula (1) or a compound represented by the following general formula (2) and a compound having two or more epoxy groups.
   

   

   [In the general formula (1), R ¹ to R ⁶ each independently represents an alkyl group having 1 to 10 carbon atoms. ]
   

   

   [In the general formula (2), R ⁷ to R ¹² each independently represents an alkyl group having 1 to 10 carbon atoms. ]
8. A cured pattern film comprising a cured product of a resin film comprising the positive photosensitive resin composition according to any one of claims 1 to 5, wherein the pattern has a pattern.
9. Applying the positive photosensitive resin composition according to any one of claims 1 to 6 to a part or all of a substrate and drying to form a resin film;
   Exposing part or all of the resin film;
   Developing the resin film after exposure with an aqueous alkaline solution to form a patterned resin film;
   Heating the pattern resin film;
   A method for producing a patterned cured film.
10. A semiconductor element comprising the patterned cured film according to claim 8 as an interlayer insulating layer or a surface protective layer.
11. An electronic device comprising the semiconductor element according to claim 10.

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