Negative photosensitive polymer

Abstract

To provide a negative photosensitive polymer that has excellent solubility in an organic solvent and is less prone to hydrolysis and can give a cured product, such as a film, having high mechanical strength.SOLUTION: A negative photosensitive polymer has an imide constitutional unit, an aromatic condensed constitutional unit and a biphenyl constitutional unit having a methacryloyl group.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a negative photosensitive polymer.

Background Art

[0002] Polyimide resins have high mechanical strength, heat resistance, insulation properties, and solvent resistance, and are therefore widely used as thin films for electronic materials such as protective materials, insulating materials, and color filters in liquid crystal display elements and semiconductors.

[0003] Patent Document 1 discloses a liquid crystal aligning agent containing at least one polymer selected from the group consisting of a polyamic acid obtained by reacting a tetracarboxylic dianhydride with a diamine and a polyimide obtained by dehydrating and ring-closing the polyamic acid. In this document, 1-(4-aminophenyl)-2,3-dihydro-1,3,3-trimethyl-1H-inden-5-amine (hereinafter also referred to as TMDA) is mentioned as the diamine.

[0004] Patent Document 2 discloses a polyimide polymer containing a reaction product of a diamine, a tetracarboxylic dianhydride, and a compound having a predetermined functional group. In this document, TMDA is mentioned as the diamine.

[0005] Patent Document 3 discloses a dry film structure including a carrier substrate and a photosensitive polymer layer containing a fully imidized polyimide polymer. In this document, TMDA is mentioned as the diamine constituting the fully imidized polyimide polymer.

[0006] Patent Document 4 discloses a photosensitive composition containing a fully imidized polyimide polymer, a solubility switching compound, a photoinitiator, and a solvent, which can form a film having a predetermined dissolution rate. In this document, TMDA is mentioned as the diamine constituting the fully imidized polyimide polymer.

[0007] Patent Document 5 discloses a photosensitive resin composition containing a polyimide resin having a predetermined structure and a weight average molecular weight of 70,000 or less. It is described in the document that at least one of the ends of the polyimide resin is a group containing a (meth)acrylate group.

Prior Art Documents

Patent Documents

[0008]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Summary of the Invention

Problems to be Solved by the Invention

[0009] However, in the conventional technologies described in Patent Documents 1 to 5, there was room for improvement in the mechanical strength of the film containing polyimide obtained from the photosensitive resin composition.

[0010] Conventionally, in order to improve the solubility of polyimide in an organic solvent, a fluorine atom has been introduced into the polyimide skeleton. However, the inventors have found that when polyimide is synthesized using a diamine compound containing a fluorine atom, the strong electron-withdrawing property of the fluorine atom affects the electrons of the imide ring, making the resulting polyimide susceptible to hydrolysis, thereby reducing the mechanical strength. That is, there was room for improvement in the balance between the solubility of conventional polyimide in an organic solvent and its mechanical strength.

Means for Solving the Problems

[0011] The inventors of the present invention have found that the above problems can be solved by a polyimide having a specific structure, and have completed the present invention. That is, the present invention can be shown as follows.

[0012] According to the present invention, a structural unit (a1) represented by the following general formula (a1), a structural unit (a2) represented by the following general formula (a2), a structural unit (a3) represented by the following general formula (a3), A negative photosensitive polymer containing the same is provided. [Chemical formula] [Chemical formula] [Chemical formula] (In the general formula (a1), Y is a divalent organic group. In the general formula (a2), R 1 , R 2 each independently represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or an alkoxy group having 1 to 3 carbon atoms. A plurality of R 1 's, a plurality of R 2 's may be the same or different from each other. In the general formula (a3), Q represents a divalent to tetravalent organic group having 1 to 10 carbon atoms, and a plurality of Q's may be the same or different from each other. R 5 and R 6 each independently represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or an alkoxy group having 1 to 3 carbon atoms. m1 and m2 each independently represent an integer of 1 to 3. X represents a single bond, -SO2-, -C(=O)-, or a linear or branched alkylene having 1 to 5 carbon atoms group shown, and a plurality of X's may be the same or different from each other.) [Advantages of the Invention]

[0013] According to the present invention, it is possible to provide a negative photosensitive polymer that has excellent solubility in an organic solvent, is suppressed in hydrolysis, and can obtain a cured product such as a film having excellent mechanical strength.

Brief Description of the Drawings

[0014]

Figure 1

Modes for Carrying Out the Invention

[0015] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings, the same components are denoted by the same reference numerals, and the description will be omitted as appropriate. Further, "A to B" represents "A or more" to "B or less" unless otherwise specified.

[0016] The negative photosensitive polymer of this embodiment includes a structural unit (a1) represented by the following general formula (a1), a structural unit (a2) represented by the following general formula (a2), and a structural unit (a3) represented by the following general formula (a3).

[0017]

Chemical formula

[0018] In the general formula (a1), Y is a divalent organic group. As the divalent organic group, a known organic group can be used within the range where the effects of the present invention are exhibited. From the viewpoint of the effects of the present invention, it is preferably a divalent organic group selected from the following general formula (a1-1), the following general formula (a1-2), and the following general formula (a1-3).

[0019]

Chemical formula

[0020] In the general formula (a1-1), R 7 and R8 each independently represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or an alkoxy group having 1 to 3 carbon atoms, and a plurality of R's 7 among themselves, a plurality of R's 8 among themselves may be the same or different. R 7 and R 8 from the viewpoint of the effects of the present invention, are preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and more preferably a hydrogen atom. R 9 represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or an alkoxy group having 1 to 3 carbon atoms, and a plurality of R's 9 among themselves may be the same or different. R 9 from the viewpoint of the effects of the present invention, are preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and more preferably a hydrogen atom. * represents a bond.

[0021] In the general formula (a1-2), R 10 and R 11 each independently represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or an alkoxy group having 1 to 3 carbon atoms, and a plurality of R's 10 among themselves, a plurality of R's 11 among themselves may be the same or different.

[0022] R 10 and R 11 from the viewpoint of the effects of the present invention, are preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and more preferably at least one of R 10 and at least one of R 11 is an alkyl group having 1 to 3 carbon atoms, and more preferably three R's 10 are alkyl groups having 1 to 3 carbon atoms, one R 10 is a hydrogen atom, and three R's 11 are alkyl groups having 1 to 3 carbon atoms, one R 11 is a hydrogen atom, and particularly preferably three R's 10 are methyl groups, one R 10 is a hydrogen atom, and three R's 11is a methyl group and one R 11 is a hydrogen atom. * represents a bond.

[0023] In the general formula (a1-3), Z represents an alkylene group having 1 to 5 carbon atoms or a divalent aromatic group. * represents a bond.

[0024]

Chemical formula

[0025] In the general formula (a2), R 1 , R 2 each independently represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or an alkoxy group having 1 to 3 carbon atoms. When there are a plurality of Rs 1 among themselves, and when there are a plurality of Rs 2 among themselves, they may be the same or different. R 1 , R 2 From the viewpoint of the effects of the present invention, a hydrogen atom or an alkyl group having 1 to 3 carbon atoms is preferable, and a hydrogen atom is more preferable.

[0026] Since the polyimide (A) of the present embodiment contains a structural unit represented by the general formula (a2), the influence on the electrons of the imide ring is suppressed, the hydrolysis of the polyimide is suppressed, it has excellent mechanical strength, and it also has excellent solubility in organic solvents. In other words, the polyimide (A) of the present embodiment and the negative photosensitive resin composition containing the polyimide (A) are excellent in the balance of these properties.

[0027]

Chemical formula

[0028] In the general formula (a3), Q represents a divalent to tetravalent organic group having 1 to 10 carbon atoms, and when there are a plurality of Qs, they may be the same or different.

[0029] Examples of the divalent to tetravalent organic groups having 1 to 10 carbon atoms include ester groups, divalent to tetravalent aliphatic hydrocarbon groups having 1 to 10 carbon atoms, divalent to tetravalent alicyclic hydrocarbon groups having 3 to 10 carbon atoms, etc. These hydrocarbon groups may contain heteroatoms such as oxygen, nitrogen, and sulfur atoms, and may have ester bonds, thioester bonds, urethane bonds, thiourethane bonds, etc. in the structure. R 5 and R 6 each independently represent a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or an alkoxy group having 1 to 3 carbon atoms. m1 and m2 each independently represent an integer of 1 to 3.

[0030] X represents a single bond, -SO2-, -C(=O)-, a linear or branched alkylene group having 1 to 5 carbon atoms, or a linear or branched fluoroalkylene group having 1 to 5 carbon atoms, and a plurality of Xs may be the same or different.

[0031] From the viewpoint of the effects of the present invention, X is preferably a linear or branched alkylene group having 1 to 5 carbon atoms, or a linear or branched fluoroalkylene group having 1 to 5 carbon atoms. Specifically, the polyimide (A) of the present embodiment can contain a structural unit represented by the following general formula (1).

[0032] [Chemical formula]

[0033] In the general formula (1), R 1 , R 2 is synonymous with the general formula (a2), and Y is synonymous with the general formula (a1). Specifically, the polyimide (A) of the present embodiment can contain a structural unit represented by the following general formula (2) together with the structural unit represented by the above general formula (1).

[0034] [Chemical formula]

[0035] In general formula (2), Q, R 5 , R 6 , m1, m2, and X are synonymous with general formula (a3), and Y is synonymous with general formula (a1). Specifically, the polyimide (A) of the present embodiment can contain a structural unit represented by the above general formula (3).

[0036]

Chemical formula

[0037] In general formula (3), Q, R 5 , R 6 , m1, m2, and X are synonymous with general formula (a3), Y is synonymous with general formula (a1), and R 1 , R 2 is synonymous with general formula (a2). The polyimide (A) of the present embodiment contains the above structural unit, and may further contain the following structural unit in part.

[0038]

Chemical formula

[0039] In the present embodiment, it is preferable that at least one of both ends of the polyimide (A) is a (meth) acrylate group. By including this group, hydrolysis is suppressed and the mechanical strength is further excellent. The weight average molecular weight of the polyimide (A) of the present embodiment is 5,000 to 200,000, preferably 10,000 to 100,000.

[0040] The polyimide (A) (negative photosensitive polymer) of the present embodiment is excellent in hydrolysis resistance, and the reduction rate of the weight average molecular weight measured under the following conditions is 15% or less, preferably 12% or less, more preferably 10% or less, and particularly preferably 5% or less. (Condition) When 400 parts by mass of γ-butyrolactone, 200 parts by mass of 4-methyltetrahydropyran, and 50 parts by mass of water are added to 100 parts by mass of the negative photosensitive polymer and stirred at 100 °C for 6 hours, it is calculated by the following formula. Formula: [(weight average molecular weight before the test - weight average molecular weight after the test) / weight average molecular weight before the test] × 100

[0041] Since the negative photosensitive polymer of this embodiment has a weight average molecular weight reduction rate within the above range, a cured product such as a film excellent in mechanical strength such as elongation can be obtained.

[0042] In addition, the polyimide (A) of this embodiment is excellent in solubility in a solvent and does not need to be made into a varnish in the state of a precursor. Therefore, a varnish containing polyimide (A) can be prepared, and a cured product such as a film can be obtained from the varnish.

[0043] <Method for producing polyimide (A)> The method for producing the polyimide (A) (negative photosensitive polymer) having the structural unit represented by the general formula (1) and the structural unit represented by the general formula (2) of this embodiment, or the polyimide (A) (negative photosensitive polymer) having the structural unit represented by the general formula (3) is

[0044] Step 1 of imidizing an acid anhydride (a1') represented by the following general formula (a1'), a diamine (a2') represented by the following general formula (a2'), and a bisaminophenol (a3') represented by the following general formula (a3') at a temperature of 100 °C or higher and 250 °C or lower;

[0045] Step 2 of reacting a compound having a (meth)acrylate group with the hydroxyl group of the structural unit derived from the bisaminophenol (a3') of the general formula (a3') of the polymer obtained in Step 1 to introduce a group containing a (meth)acrylate group; and includes. According to this embodiment, polyimide (A) excellent in solubility in an organic solvent can be synthesized by a simple method.

[0046] [Chemistry]

[0047] In the general formula (a1'), Y is selected from the groups represented by the general formula (a1-1), (a1-2) or (a1-3).

[0048] [Chemistry]

[0049] In the general formula (a2'), R 1 , R 2 is synonymous with the general formula (a2).

[0050] [Chemistry]

[0051] In the general formula (a3'), X is synonymous with the general formula (a3). In order to control the molecular weight of the resulting polyhydroxyimide, it is also possible to carry out the reaction by adding a small amount of acid anhydride or aromatic amine as an end-capping agent.

[0052] Examples of the acid anhydride as the end-capping agent include phthalic anhydride, maleic anhydride, nadic anhydride, etc., and examples of the aromatic amine include p-methylaniline, p-methoxyaniline, p-phenoxyaniline, etc. The addition amount of these acid anhydrides or aromatic amines as the end-capping agent is preferably 5 mol% or less. If it exceeds 5 mol%, the molecular weight of the resulting polyhydroxyimide will decrease significantly, causing problems in heat resistance and mechanical properties.

[0053] In the imidization reaction of Project 1, the equivalent ratio of acid anhydride (a1'), diamine (a2'), and bisaminophenol (a3') is an important factor in determining the molecular weight of the resulting polymer. Generally, it is well known that there is a correlation between the molecular weight of a polymer and its mechanical properties, and the higher the molecular weight, the better the mechanical properties. Therefore, in order to obtain a polymer with practically excellent strength, it is necessary to have a certain high molecular weight. In the present invention, the equivalent ratio of acid anhydride (a1'), diamine (a2'), and bisaminophenol (a3') used is not particularly limited, but the equivalent ratio of diamine (a2') and bisaminophenol (a3') to acid anhydride (a1') is preferably in the range of 0.70 to 1.3. If the equivalent ratio is within the above range, it has excellent mechanical strength and excellent production stability.

[0054] Note that from the perspective of improving mechanical properties, even when the equivalent ratio of diamine (a2') and bisaminophenol (a3') to acid anhydride (a1') is outside the above range, the apparent molecular weight can also be increased by side-chain crosslinking the resin. Project 1 (imidization reaction step) can be carried out by a known method in an organic solvent.

[0055] Examples of the organic solvent include aprotic polar solvents such as γ-butyrolactone (GBL), N,N-dimethylformamide, N,N-dimethylacetamide, tetrahydrofuran, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, cyclohexanone, and 1,4-dioxane. One kind or a combination of two or more kinds may be used. At this time, a nonpolar solvent compatible with the above aprotic polar solvent may be mixed and used. Examples of the nonpolar solvent include aromatic hydrocarbons such as toluene, ethylbenzene, xylene, mesitylene, and solvent naphtha, and ether solvents such as cyclopentyl methyl ether. Regarding the ratio of the nonpolar solvent in the mixed solvent, it can be arbitrarily set according to the resin properties such as the stirring device capacity and solution viscosity as long as the solubility of the solvent does not decrease and the polyamic acid resin obtained by the reaction does not precipitate.

[0056] The reaction temperature is 0°C or higher and 100°C or lower, preferably 20°C or higher and 80°C or lower, and the reaction is carried out for about 30 minutes to 2 hours, and then the reaction is carried out at 100°C or higher and 250°C or lower, preferably 120°C or higher and 200°C or lower for about 1 to 5 hours.

[0057] In Step 1, a polyhydroxyimide having a structural unit represented by the following general formula (1) and a structural unit represented by the following general formula (2') or a polyhydroxyimide containing a constitutional unit having a structural unit represented by the following general formula (3') can be obtained. In Step 1, the polyhydroxyimide can be purified by a known method, but the dehydration efficiency in polymerization can be improved, and Steps 1 and 2 can be continuously carried out without purifying the obtained polyhydroxyimide.

[0058]

Chemical formula

[0059] In Step 2, a compound having a (meth)acrylate group is reacted with the hydroxyl group of the polyhydroxyimide obtained in Step 1 to introduce a crosslinking group containing a (meth)acrylate group. The crosslinking group introduced into the polyimide (A) reacts with a crosslinking agent (B) described later in the exposure step, and the exposed portion becomes insoluble in an organic solvent.

[0060] Examples of the compound having a (meth)acrylate group include 2-isocyanatoethyl (meth)acrylate, 2-(2-(meth)acryloyloxyethyloxy)ethyl isocyanate, 1,1-(bisacryloyloxymethyl)ethyl isocyanate, glycidyl methacrylate, 4-hydroxybutyl acrylate glycidyl ether, and the like.

[0061] To introduce a crosslinking group containing a (meth)acrylate group into a polyhydroxyimide, in an organic solvent, a polyhydroxyimide and a compound having a (meth)acrylate group are mixed, and the reaction is carried out at 60 °C to 150 °C for about 2 to 10 hours. The reaction is not particularly limited, but it can be carried out at normal pressure.

[0062] The compound having a (meth)acrylate group can be appropriately selected according to the amount of the crosslinking group introduced into the polyhydroxyimide. For example, it can be added so as to be 0.8 to 3.0 molar times the molar amount of the hydroxyl group of the polyhydroxyimide, and preferably 2.0 to 3.0 molar times. When the polyhydroxyimide has a group capable of introducing a crosslinking group, that group can be added to the molar amount.

[0063] Examples of the organic solvent include aprotic polar solvents such as γ-butyrolactone (GBL), N,N-dimethylformamide, N,N-dimethylacetamide, tetrahydrofuran, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, cyclohexanone, and 1,4-dioxane. One kind or a combination of two or more kinds may be used. At this time, a nonpolar solvent compatible with the aprotic polar solvent may be mixed and used. Examples of the nonpolar solvent include aromatic hydrocarbons such as toluene, ethylbenzene, xylene, mesitylene, and solvent naphtha, and ether solvents such as cyclopentyl methyl ether. In the reaction, a base such as triethylamine or 1,1,3,3-tetramethylguanidine can also be added.

[0064] By Step 2, a polyimide (A) having a structural unit represented by the general formula (1) and a structural unit represented by the general formula (2), or a polyimide (A) having a structural unit represented by the general formula (3) can be obtained.

[0065] In Step 2, the reaction solution containing the polyhydroxyimide obtained in Step 1 can be purified by reprecipitation or the like, and the obtained polyhydroxyimide can be used. However, the reaction solution of Step 1 can be directly used in Step 2.

[0066] By the production method of the present embodiment described above, a reaction solution containing the polyimide (A) (negative photosensitive polymer) of the present embodiment can be obtained. Further, if necessary, it can be diluted with an organic solvent or the like and used as a polymer solution (coating varnish). As the organic solvent, those exemplified in the reaction step can be used, and it may be the same organic solvent as in the reaction step or a different organic solvent.

[0067] Also, this reaction solution can be poured into a poor solvent to reprecipitate and precipitate the polyimide (A) resin to remove unreacted monomers, and the dried and solidified product can be dissolved in an organic solvent again and used as a purified product. Particularly in applications where impurities and foreign matters are a problem, it is preferable to dissolve it in an organic solvent again to obtain a filtered and purified varnish.

[0068] <Negative photosensitive resin composition> In the present embodiment, the negative photosensitive resin composition can contain the above-mentioned negative photosensitive polymer. The negative photosensitive resin composition of the present embodiment contains a negative photosensitive polymer and is not particularly limited as long as it is negatively photosensitive. For example, it preferably contains a negative photosensitive polymer (polyimide (A)), a crosslinking agent (B) containing a polyfunctional (meth)acrylate, and a photopolymerization initiator (C).

[0069] [Crosslinking agent (B)] The crosslinking agent (B) contains a polyfunctional (meth)acrylate. The polyfunctional (meth)acrylate is a compound having two or more (meth)acryloyl groups, and a conventionally known compound can be used as long as the effects of the present invention can be exhibited. In the present embodiment, the (meth)acrylic group refers to an acrylic group or a methacrylic group.

[0070] Specific polyfunctional (meth)acrylates include bifunctional (meth)acrylates such as diethylene glycol di(meth)acrylate, polyethylene glycol #200 di(meth)acrylate, polyethylene glycol #400 di(meth)acrylate, etc., trifunctional (meth)acrylates such as trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, ethoxylated isocyanuric acid triacrylate, etc., tetrafunctional (meth)acrylates such as pentaerythritol tetra(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, etc., hexafunctional (meth)acrylates such as dipentaerythritol hexa(meth)acrylate, etc., octafunctional (meth)acrylates such as tripentaerythritol octa(meth)acrylate, etc., and decafunctional (meth)acrylates such as tetrapentaerythritol deca(meth)acrylate. Among these, one or more of them may be used.

[0071] From the viewpoint of the effects of the present invention, the amount of the crosslinking agent (B) relative to 100 parts by mass of the polyimide (A) can be 1 part by mass or more and 30 parts by mass or less, preferably 2 parts by mass or more and 20 parts by mass or less, more preferably 3 parts by mass or more and 15 parts by mass or less. By being within this range, the elongation is further improved.

[0072] [Photopolymerization initiator (C)] As the photopolymerization initiator (C), for example, a photo radical generator can be used. The photo radical generator contains a photo radical generator that generates radicals upon irradiation with active light such as ultraviolet rays and functions as a photopolymerization initiator for the above-described polyimide (A).

[0073] Examples of the photo radical generator include alkylphenone type initiators, oxime ester type initiators, acylphosphine oxide type initiators, etc. For example, 1-hydroxycyclohexyl phenyl ketone, 2,2-dimethoxy-1,2-diphenylethane-1-one, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propan-1-one, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, 1,2-octanedione, 1-[4-(phenylthio)-, 2-(O-benzoyloxime)), ethanone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-, 1-(0-acetoxyoxime), 2-(dimethylamino)-1-(4-(4-morpholino)phenyl)-2-(phenylmethyl)-1-butanone, Irgacure Oxe01 (BASF Japan Ltd.), Irgacure Oxe02 (BASF Japan Ltd.), Irgacure Oxe03 (BASF Japan Ltd.), Irgacure Oxe04 (BASF Japan Ltd.), N-1919T (ADEKA Corporation), NCI-730 (ADEKA Corporation), NCI-831E (ADEKA Corporation), NCI-930 (ADEKA Corporation), etc. Any one or more of these can be used. Among these, from the viewpoint of the effects of the present invention and further from the viewpoint of producing a resin film composed of a photosensitive resin composition having more excellent exposure sensitivity, oxime ester type initiators are preferred.

[0074] The addition amount of the polymerization initiator (C) is not particularly limited, but is preferably about 0.3 to 20% by mass, more preferably about 0.5 to 15% by mass, and even more preferably about 1 to 10% by mass based on 100% by mass of the non-volatile components excluding the solvent of the negative photosensitive resin composition. By setting the addition amount of the polymerization initiator (C) within the above range, the patterning property of the photosensitive resin layer containing the negative photosensitive resin composition can be enhanced, and the long-term storage stability of the negative photosensitive resin composition can be improved.

[0075] (Solvent) The negative photosensitive resin composition according to the present embodiment can contain a solvent. Thereby, a uniform photosensitive resin film can be formed on the surfaces of various substrates.

[0076] An organic solvent is preferably used as the solvent. Specifically, one or more of a ketone solvent, an ester solvent, an ether solvent, an alcohol solvent, a lactone solvent, a carbonate solvent, etc. can be used.

[0077] Examples of the solvent include propylene glycol monomethyl ether (PGME), propylene glycol monomethyl ether acetate (PGMEA), ethyl lactate, methyl isobutyl carbinol (MIBC), gamma-butyrolactone (GBL), N-methylpyrrolidone (NMP), methyl-n-amyl ketone (MAK), diethylene glycol monomethyl ether, diethylene glycol dimethyl ether, diethylene glycol methyl ethyl ether, cyclohexanone, or a mixture thereof. The amount of the solvent used is not particularly limited. For example, it is used in an amount such that the concentration of the non-volatile components is, for example, 10 to 70% by mass, preferably 15 to 60% by mass.

[0078] (Surfactant) The negative photosensitive resin composition according to the present embodiment may further contain a surfactant. Examples of the surfactant include, but are not limited to, nonionic surfactants such as polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, and polyoxyethylene oleyl ether; polyoxyethylene aryl ethers such as polyoxyethylene octyl phenyl ether and polyoxyethylene nonyl phenyl ether; polyoxyethylene dialkyl esters such as polyoxyethylene dilaurate and polyoxyethylene distearate; fluorosurfactants commercially available under names such as Ftop EF301, Ftop EF303, Ftop EF352 (manufactured by Shin-Akita Kasei Co., Ltd.), Megafac F171, Megafac F172, Megafac F173, Megafac F177, Megafac F444, Megafac F470, Megafac F471, Megafac F475, Megafac F482, Megafac F477 (manufactured by DIC Corporation), Fluorad FC-430, Fluorad FC-431, Novec FC4430, Novec FC4432 (manufactured by 3M Japan Ltd.), Surflon S-381, Surflon S-382, Surflon S-383, Surflon S-393, Surflon SC-101, Surflon SC-102, Surflon SC-103, Surflon SC-104, Surflon SC-105, Surflon SC-106 (manufactured by AGC Seimi Chemical Co., Ltd.); organosiloxane copolymer KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.); (meth)acrylic acid copolymer Polyflow No. 57, 95 (manufactured by Kyoeisha Chemical Co., Ltd.).

[0079] Among these, it is preferable to use a fluorosurfactant having a perfluoroalkyl group. As the fluorosurfactant having a perfluoroalkyl group, one or more selected from Megafac F171, Megafac F173, Megafac F444, Megafac F470, Megafac F471, Megafac F475, Megafac F482, Megafac F477 (manufactured by DIC Corporation), Surflon S-381, Surflon S-383, Surflon S-393 (manufactured by AGC Seimi Chemical Co., Ltd.), Novec FC4430, and Novec FC4432 (manufactured by 3M Japan Ltd.) is preferably used.

[0080] In addition, as the surfactant, silicone surfactants (such as polyether-modified dimethylsiloxane) can also be preferably used. Specifically, as silicone surfactants, the SH series, SD series and ST series of Toray Dow Corning, the BYK series of Big Chemie Japan, the KP series of Shin-Etsu Chemical Co., Ltd., the Disform (registered trademark) series of NOF Corporation, the TSF series of Toshiba Silicone Co., Ltd., etc. can be mentioned.

[0081] The upper limit of the content of the surfactant in the negative photosensitive resin composition is preferably 1% by mass (10,000 ppm) or less, more preferably 0.5% by mass (5,000 ppm) or less, and still more preferably 0.1% by mass (1,000 ppm) or less with respect to the whole of the negative photosensitive resin composition (including the solvent).

[0082] In addition, there is no particular lower limit for the content of the surfactant in the negative photosensitive resin composition, but from the viewpoint of sufficiently obtaining the effects of the surfactant, for example, it is 0.001% by mass (10 ppm) or more with respect to the whole of the negative photosensitive resin composition (including the solvent). By appropriately adjusting the amount of the surfactant, it is possible to improve coatability, film uniformity, etc. while maintaining other performances.

[0083] (Antioxidant) The negative photosensitive resin composition according to this embodiment may further contain an antioxidant. As the antioxidant, one or more selected from phenolic antioxidants, phosphorus antioxidants and thioether antioxidants can be used. The antioxidant can suppress the oxidation of the resin film formed by the negative photosensitive resin composition.

[0084] Examples of phenolic antioxidants include pentaerythrityl - tetrakis〔3-(3,5 - di - t - butyl - 4 - hydroxyphenyl)propionate〕, 3,9 - bis{2 - 〔3-(3 - t - butyl - 4 - hydroxy - 5 - methylphenyl)propionyloxy〕 - 1,1 - dimethylethyl}2,4,8,10 - tetraoxaspiro〔5,5〕undecane, octadecyl - 3-(3,5 - di - t - butyl - 4 - hydroxyphenyl)propionate, 1,6 - hexanediol - bis〔3-(3,5 - di - t - butyl - 4 - hydroxyphenyl)propionate〕, 1,3,5 - trimethyl - 2,4,6 - tris(3,5 - di - t - butyl - 4 - hydroxybenzyl)benzene, 2,6 - di - t - butyl - 4 - methylphenol, 2,6 - di - t - butyl - 4 - ethylphenol, 2,6 - diphenyl - 4 - octadecyloxyphenol, stearyl(3,5 - di - t - butyl - 4 - hydroxyphenyl)propionate, distearyl(3,5 - di - t - butyl - 4 - hydroxybenzyl)phosphonate, thiodiethylene glycol bis〔(3,5 - di - t - butyl - 4 - hydroxyphenyl)propionate〕, 4,4' - thiobis(6 - t - butyl - m - cresol), 2 - octylthio - 4,6 - di(3,5 - di - t - butyl - 4 - hydroxyphenoxy)-s - triazine, 2,2' - methylenebis(4 - methyl - 6 - t - butylphenol), 2, - 2' - methylenebis(4 - ethyl - 6 - t - butylphenol), bis〔3,3 - bis(4 - hydroxy - 3 - t - butylphenyl)butyric acid〕glycol ester, 4,4' - butylidenebis(6 - t - butyl - m - cresol), 2,2' - ethylidenebis(4,6 - di - t - butylphenol), 2,2' - ethylidenebis(4 - s - butyl - 6 - t - butylphenol), 1,1,3 - tris(2 - methyl - 4 - hydroxy - 5 - t - butylphenyl)butane, bis〔2 - t - butyl - 4 - methyl - 6-(2 - hydroxy - 3 - t - butyl - 5 - methylbenzyl)phenyl〕terephthalate, 1,3,5 - tris(2,6 - dimethyl - 3 - hydroxy - 4 - t - butylbenzyl)isocyanurate, 1,3,5 - tris(3,5 - di - t - butyl - 4 - hydroxybenzyl)-2,4,6 - trimethylbenzene, 1,3,5-Tris[(3,5-di-t-butyl-4-hydroxyphenyl)propionyloxyethyl] isocyanurate, tetrakis[methylene-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate] methane, 2-t-butyl-4-methyl-6-(2-acryloyloxy-3-t-butyl-5-methylbenzyl)phenol, 3,9-bis(1,1-dimethyl-2-hydroxyethyl)-2,4,8,10-tetraoxaspiro[5,5]undecane-bis[β-(3-t-butyl-4-hydroxy-5-methylphenyl)propionate], triethylene glycol bis[β-(3-t-butyl-4-hydroxy-5-methylphenyl)propionate], 1,1'-bis(4-hydroxyphenyl)cyclohexane, 2,2'-methylenebis(4-methyl-6-t-butylphenol), 2,2'-methylenebis(4-ethyl-6-t-butylphenol), 2,2'-methylenebis(6-(1-methylcyclohexyl)-4-methylphenol), 4,4'-butylidenebis(3-methyl-6-t-butylphenol), 3,9-bis(2-(3-t-butyl-4-hydroxy-5-methylphenylpropionyloxy)1,1-dimethylethyl)-2,4,8,10-tetraoxaspiro(5,5)undecane, 4,4'-thiobis(3-methyl-6-t-butylphenol), 4,4'-bis(3,5-di-t-butyl-4-hydroxybenzyl) sulfide, 4,4'-thiobis(6-t-butyl-2-methylphenol), 2,5-di-t-butylhydroquinone, 2,5-di-t-amylhydroquinone, 2-t-butyl-6-(3-t-butyl-2-hydroxy-5-methylbenzyl)-4-methylphenyl acrylate, 2,4-dimethyl-6-(1-methylcyclohexyl), styrenated phenol, 2,4-bis((octylthio)methyl)-5-methylphenol, and the like.

[0085] Examples of phosphorus-based antioxidants include bis(2,6-di-t-butyl-4-methylphenyl)pentaerythritol diphosphite, tris(2,4-di-t-butylphenyl phosphite), tetrakis(2,4-di-t-butyl-5-methylphenyl)-4,4'-biphenylenediphosphonite, 3,5-di-t-butyl-4-hydroxybenzyl phosphonate-diethyl ester, bis-(2,6-dicumylphenyl)pentaerythritol diphosphite, 2,2-methylenebis(4,6-di-t-butylphenyl) octyl phosphite, tris(mixed mono- and di-nonylphenyl phosphite), bis(2,4-di-t-butylphenyl)pentaerythritol diphosphite, bis(2,6-di-t-butyl-4-methoxycarbonylethyl-phenyl)pentaerythritol diphosphite, bis(2,6-di-t-butyl-4-octadecyloxycarbonylethylphenyl)pentaerythritol diphosphite, and the like.

[0086] Examples of thioether-based antioxidants include dilauryl 3,3'-thiodipropionate, bis(2-methyl-4-(3-n-dodecyl)thiopropionyloxy)-5-t-butylphenyl) sulfide, distearyl 3,3'-thiodipropionate, pentaerythritol-tetrakis(3-lauryl)thiopropionate, and the like.

[0087] (Adhesion promoter) The negative photosensitive resin composition according to this embodiment may further contain an adhesion promoter. As the adhesion promoter, for example, silane coupling agents such as aminosilane, epoxysilane, (meth)acryl silane, mercaptosilane, vinyl silane, ureido silane, acid anhydride functional type silane, sulfide silane, etc. can be used. The silane coupling agent may be used alone or in combination of two or more. Among these, epoxysilane (that is, a compound containing both an epoxy moiety and a group that generates a silanol group by hydrolysis) or acid anhydride functional type silane (that is, a compound containing both an acid anhydride group and a group that generates a silanol group by hydrolysis) is preferable.

[0088] Examples of aminosilane include bis(2-hydroxyethyl)-3-aminopropyltriethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropylmethyldiethoxysilane, γ-aminopropylmethyldimethoxysilane, N-β(aminoethyl)γ-aminopropyltrimethoxysilane, N-β(aminoethyl)γ-aminopropyltriethoxysilane, N-β(aminoethyl)γ-aminopropylmethyldimethoxysilane, N-β(aminoethyl)γ-aminopropylmethyldiethoxysilane, or N-phenyl-γ-amino-propyltrimethoxysilane, etc.

[0089] Examples of epoxysilane include γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, or β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, γ-glycidylpropyltrimethoxysilane, etc.

[0090] Examples of acryl silane include γ-(methacryloxypropyl)trimethoxysilane, γ-(methacryloxypropyl)methyldimethoxysilane, or γ-(methacryloxypropyl)methyldiethoxysilane, etc. Examples of mercaptosilane include 3-mercaptopropyltrimethoxysilane, etc.

[0091] Examples of vinyl silanes include vinyltris(β-methoxyethoxy)silane, vinyltriethoxysilane, vinyltrimethoxysilane, and the like. Examples of ureido silanes include 3-ureidopropyltriethoxysilane and the like.

[0092] Examples of acid anhydride functional silanes include those manufactured by Shin-Etsu Chemical Co., Ltd., such as the product name X-12-967C (compound name: 3-trimethoxysilylpropyl succinic anhydride).

[0093] Examples of sulfide silanes include bis(3-(triethoxysilyl)propyl) disulfide, bis(3-(triethoxysilyl)propyl) tetrasulfide, and the like. The addition amount of the adhesion promoter is not particularly limited, but is 0.1 to 5% by mass, preferably 0.5 to 3% by mass, based on the total solid content of the negative photosensitive resin composition.

[0094] (Preparation of Negative Photosensitive Resin Composition) The method for preparing the negative photosensitive resin composition in this embodiment is not limited, and a known method can be used according to the components contained in the negative photosensitive resin composition. For example, it can be prepared by mixing and dissolving the above components in a solvent.

[0095] (Negative Photosensitive Resin Composition) The negative photosensitive resin composition according to this embodiment is applied to a surface provided with a metal such as Al or Cu, then pre-baked to dry and form a resin film, then the resin film is patterned into a desired shape by exposure and development, and then the resin film is heat-treated to be cured to form a cured film for use.

[0096] In the case of producing the above permanent film, as the pre-baking conditions, for example, heat treatment can be performed at a temperature of 90°C or higher and 130°C or lower for 30 seconds or longer and 1 hour or shorter. Further, as the heat treatment conditions, for example, heat treatment can be performed at a temperature of 150°C or higher and 250°C or lower for 30 minutes or longer and 10 hours or shorter, and preferably at about 170°C for 1 to 6 hours.

[0097] The film obtained from the negative photosensitive resin composition of this embodiment has an elongation rate measured by a tensile test using a tensilon tester with a maximum value of 15 to 200%, preferably 20 to 150%, and an average value of 10 to 150%, preferably 15 to 120%. Further, since the negative photosensitive resin composition of this embodiment contains a polyimide (A) (negative photosensitive polymer) having excellent hydrolysis resistance, even after performing a HAST test (unsaturated pressurized steam test) for 96 hours under the conditions of a temperature of 130°C and a relative humidity of 85% RH, the reduction rate of the elongation rate (maximum value, average value) represented by the following formula is 20% or less, preferably 15% or less, and more preferably 12% or less. [(Elongation rate before test - Elongation rate after test) / Elongation rate before test] × 100

[0098] The negative photosensitive resin composition of this embodiment is excellent in low-temperature curability. For example, the cured product obtained by curing the negative photosensitive resin composition of this embodiment at 170°C for 4 hours can have a glass transition temperature (Tg) of 200°C or higher, preferably 210°C or higher, and more preferably 220°C or higher.

[0099] Furthermore, the cured product obtained by curing the negative photosensitive resin composition of this embodiment at 170°C for 4 hours can have a storage elastic modulus E' at 30°C of 2.0 GPa or higher, preferably 2.5 GPa or higher, and more preferably 3.0 GPa or higher. Further, the storage elastic modulus E' at 200°C can be 0.5 GPa or higher, preferably 0.7 GPa or higher, and more preferably 0.8 GPa or higher.

[0100] The viscosity of the negative photosensitive resin composition according to this embodiment can be appropriately set according to the desired thickness of the resin film. The viscosity of the negative photosensitive resin composition can be adjusted by adding a solvent.

[0101] The cured product such as a film obtained from the negative photosensitive resin composition of this embodiment is excellent in chemical resistance. Specifically, a film is immersed in a solution of less than 99% by mass of dimethyl sulfoxide and less than 2% by mass of tetramethylammonium hydroxide at 40°C for 10 minutes, then thoroughly washed with isopropyl alcohol and air-dried, and the film thickness after treatment is measured. The film thickness change rate between the film thickness after treatment and the film thickness before treatment is calculated from the following formula and evaluated as the reduction rate of the film. Formula: Reduction rate of film (%) = { (film thickness after immersion - film thickness before immersion) / film thickness before immersion × 100 (%)}

[0102] The film thickness change rate is preferably 40% or less, more preferably 30% or less. Thereby, even when the cured film is subjected to the step of being immersed in dimethyl sulfoxide, the film thickness hardly decreases. Therefore, a cured film that can maintain its function even after being subjected to such a step can be obtained.

[0103] The negative photosensitive resin composition of this embodiment has suppressed curing shrinkage. Spin coating is performed on the surface of a silicon wafer so that the film thickness after drying becomes 10 μm. After pre-baking at 120°C for 3 minutes, exposure is performed with a high-pressure mercury lamp at 600 mJ / cm 2 When a film is prepared by performing heat treatment at 170°C for 120 minutes in a nitrogen atmosphere, the film thickness of the film after the pre-baking is defined as film thickness A, and the film thickness of the film after the heat treatment is defined as film thickness B. The curing shrinkage rate calculated from the following formula can preferably be 12% or less, more preferably 10% or less. Formula: Curing shrinkage rate [%] = { (film thickness A - film thickness B) / film thickness A} x 100

[0104] The negative photosensitive resin composition of this embodiment has high heat resistance, and the resulting film can have a weight loss temperature (Td5) measured by thermogravimetric differential thermal simultaneous measurement of 200 °C or higher, preferably 300 °C or higher.

[0105] The film made of the negative photosensitive resin composition of this embodiment has suppressed curing shrinkage, and the linear thermal expansion coefficient (CTE) can be 200 ppm / °C or less, preferably 100 ppm / °C or less.

[0106] The film made of the negative photosensitive resin composition of this embodiment has excellent mechanical strength, and the elastic modulus at 25 °C can be 1.0 to 5.0 GPa, preferably 1.5 to 3.0 GPa.

[0107] (Use) The negative photosensitive resin composition of this embodiment is used to form resin films for semiconductor devices such as permanent films and resists. Among these, from the viewpoints of achieving a good balance between improving the adhesion of the negative photosensitive resin composition after pre-baking and the Al pad and suppressing the generation of residues of the negative photosensitive resin composition during development, improving the adhesion between the cured film of the negative photosensitive resin composition after heat treatment and the metal, and in addition, improving the chemical resistance of the negative photosensitive resin composition after heat treatment, it is preferably used for applications using permanent films.

[0108] In this embodiment, the resin film includes the cured film of the negative photosensitive resin composition. That is, the resin film according to this embodiment is obtained by curing the negative photosensitive resin composition.

[0109] The above-mentioned permanent film is composed of a resin film obtained by subjecting the negative photosensitive resin composition to pre-baking, exposure, and development, patterning it into a desired shape, and then curing it by heat treatment. The permanent film can be used as a protective film, an interlayer film, a dam material, etc. of a semiconductor device.

[0110] The resist described above is composed of a resin film obtained by applying, for example, a negative photosensitive resin composition to an object to be masked for the resist by a method such as spin coating, roll coating, flow coating, dip coating, spray coating, doctor coating, etc., and removing the solvent from the negative photosensitive resin composition.

[0111] An example of the semiconductor device according to this embodiment is shown in FIG. 1. The semiconductor device 100 according to this embodiment can be a semiconductor device including the above resin film. Specifically, among the semiconductor device 100, one or more of the group consisting of the passivation film 32, the insulating layer 42, and the insulating layer 44 can be a resin film containing the cured product of this embodiment. Here, the resin film is preferably the permanent film described above.

[0112] The semiconductor device 100 is, for example, a semiconductor chip. In this case, for example, a semiconductor package can be obtained by mounting the semiconductor device 100 on a wiring board via bumps 52.

[0113] The semiconductor device 100 includes a semiconductor substrate provided with semiconductor elements such as transistors, and a multilayer wiring layer (not shown) provided on the semiconductor substrate. On the uppermost layer of the multilayer wiring layer, an interlayer insulating film 30 and an uppermost layer wiring 34 provided on the interlayer insulating film 30 are provided. The uppermost layer wiring 34 is composed of, for example, aluminum Al. Also, a passivation film 32 is provided on the interlayer insulating film 30 and on the uppermost layer wiring 34. An opening through which the uppermost layer wiring 34 is exposed is provided in a part of the passivation film 32.

[0114] A redistribution layer 40 is provided on the passivation film 32. The redistribution layer 40 includes an insulating layer 42 provided on the passivation film 32, a redistribution line 46 provided on the insulating layer 42, and an insulating layer 44 provided on the insulating layer 42 and the redistribution line 46. An opening for connecting to the top layer wiring 34 is formed in the insulating layer 42. The redistribution line 46 is formed on the insulating layer 42 and within the opening provided in the insulating layer 42 and is connected to the top layer wiring 34. An opening for connecting to the redistribution line 46 is provided in the insulating layer 44.

[0115] Within the opening provided in the insulating layer 44, bumps 52 are formed, for example, via an Under Bump Metallurgy (UBM) layer 50. The semiconductor device 100 is connected to a wiring board or the like, for example, via the bumps 52. As described above, embodiments of the present invention have been described, but these are examples of the present invention, and various configurations other than the above can be adopted as long as the effects of the present invention are not impaired.

Example

[0116] Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited thereto. In the examples, the following compounds were used.

[0117] 1-(4-aminophenyl)-2,3-dihydro-1,3,3-trimethyl-1H-indene-5-amine (hereinafter also referred to as TMDA) represented by the following formula

Chemical formula

[0118] 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl (hereinafter also referred to as TFMB) represented by the following formula

Chemical formula

[0119] 4,4'-(Hexafluoroisopropylidene)bis[(4-aminophenoxy)benzene] (hereinafter also referred to as HFBAPP), represented by the following formula [Chemical formula]

[0120] 2,2-Bis(3-amino-4-hydroxyphenyl)propane (hereinafter also referred to as BAPA), represented by the following formula [Chemical formula]

[0121] 2,2-Bis(3-amino-4-hydroxyphenyl)hexafluoropropane (hereinafter also referred to as BAFA), represented by the following formula [Chemical formula]

[0122] 4-[4-(1,3-Dioxoisobenzofuran-5-ylcarbonyloxy)-2,3,5-trimethylphenyl]-2,3,6-trimethylphenyl 1,3-dioxoisobenzofuran-5-carboxylate (hereinafter also referred to as TMPBP-TME), represented by the following formula [Chemical formula]

[0123] [Example 1] First, 3.54 g (13.7 mmol) of TMDA, 3.65 g (13.7 mmol) of BAPA, and 20.17 g (32.6 mmol) of TMPBP-TME were placed in a reaction vessel of appropriate size equipped with a stirrer and a cooling tube. Then, 73.87 g of GBL was further added to the reaction vessel. After purging with nitrogen for 10 minutes, the temperature was raised to 60°C with stirring and reacted for 1.5 hours. Then, by further reacting at 180°C for 3 hours, the bisaminophenol and the acid anhydride were polymerized to prepare a polymerization solution. When the polymer was measured by GPC, the weight-average molecular weight Mw was 15,800 and the polydispersity (weight-average molecular weight Mw / number-average molecular weight Mn) was 1.73. Next, to the entire amount of the obtained polyimide solution (27.4 mmol in terms of hydroxyl group), 7.73 g (54.8 mmol) of 2-isocyanatoethyl acrylate (hereinafter also referred to as AOI, manufactured by Showa Denko KK) and 23.49 g of γ-butyrolactone (GBL) were added. Then, while stirring, the temperature was raised to 120 °C and reacted for 6 hours. The obtained reaction solution was diluted with tetrahydrofuran to prepare a diluted solution, and then the diluted solution was dropped into methanol to precipitate a white solid. The obtained white solid was recovered and vacuum-dried at 40 °C to obtain 23.29 g of a polymer. When the polymer was measured by GPC, the weight-average molecular weight Mw was 17,200 and the polydispersity (weight-average molecular weight Mw / number-average molecular weight Mn) was 1.78. Also, 1 When 1H-NMR measurement was performed, peaks were confirmed at an area ratio corresponding to the number of protons in the aromatic region (6.8 ppm to 8.9 ppm). Also, from the area ratio of the aromatic region (6.8 ppm to 8.9 ppm) and the alkene region (5.8 ppm to 6.5 ppm), the introduction rate of the crosslinking group was 100%. The obtained polymer contained a repeating unit represented by the following formula in a part thereof.

[0124]

Chemical formula

[0125] [Comparative Examples 1 to 2] For Comparative Examples 1 to 2, synthesis was carried out in the same manner as in Example 1 except for the conditions described in Table 1. The obtained Mw, Mw / Mn, and crosslinking group introduction rate are shown in the table.

[0126] [Solubility in Organic Solvents] The solubility of the negative photosensitive polymers obtained in Example 1 and Comparative Examples 1 and 2 in γ-butyrolactone (GBL) was evaluated according to the following criteria. The results are shown in Table 1. (Evaluation Criteria for Solubility) ○: Polymer is dissolved at 5 mass% or more △: Polymer is dissolved at 1 - 5 mass% ×: Polymer dissolution is less than 1 mass%

[0127] [Hydrolysis Resistance] Under the following conditions, the decrease rate of the weight average molecular weight of the negative photosensitive polymers obtained in the examples and comparative examples was measured. The results are shown in Table 1. (Condition (Without Triethylamine Addition))

[0128] When 400 parts by mass of γ-butyrolactone, 200 parts by mass of 4-methyltetrahydropyran, and 50 parts by mass of water were added to 100 parts by mass of the negative photosensitive polymer and stirred at 100 °C for 6 hours, it was calculated by the following formula. Formula: [(Weight average molecular weight before the test - Weight average molecular weight after the test) / Weight average molecular weight before the test] × 100 (Condition (With Triethylamine Addition))

[0129] When 10 parts by mass of triethylamine, 400 parts by mass of γ-butyrolactone, 200 parts by mass of 4-methyltetrahydropyran, and 50 parts by mass of water were added to 100 parts by mass of the negative photosensitive polymer and stirred at 100 °C for 6 hours, it was calculated by the following formula. Formula: [(Weight average molecular weight before the test - Weight average molecular weight after the test) / Weight average molecular weight before the test] × 100

[0130]

Table 1

[0131] As shown in Table 1, the negative photosensitive polymer of the present invention obtained in the examples was excellent in solubility in organic solvents, and hydrolysis was suppressed. Therefore, it was inferred that the decrease in elongation rate was small and the decrease in mechanical strength was suppressed.

Explanation of Symbols

[0132] 100 semiconductor device 30 interlayer insulating film 32 passivation film 34 topmost layer wiring 40 rewiring layer 42 insulating layer 44 insulating layer 46 rewiring 50 UBM layer 52 bump

Claims

1. A structural unit (a1) represented by the following general formula (a1), a structural unit (a2) represented by the following general formula (a2), a structural unit (a3) represented by the following general formula (a3), and a negative-type photosensitive polymer containing the same. 【Chemical 1】 【Chemical 2】 【Chemical Formula 3】 (In general formula (a1), Y is a divalent organic group. In the general formula (a2), R １ , R ２ each independently represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or an alkoxy group having 1 to 3 carbon atoms. A plurality of R １ 's, and a plurality of R ２ 's may be the same or different from each other. In general formula (a3), Q represents a divalent to tetravalent organic group having 1 to 10 carbon atoms, and a plurality of Qs may be the same or different. R ５ and R ６ each independently represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or an alkoxy group having 1 to 3 carbon atoms. m1 and m2 each independently represent an integer of 1 to 3. X represents a single bond, -SO ２ -, -C(=O)-, or a linear or branched alkylene group having 1 to 5 carbon atoms, and a plurality of Xs may be the same or different. )

2. The negative-type photosensitive polymer according to Claim 1, wherein Y in the general formula (a1) is a divalent organic group selected from the following general formula (a1-1), the following general formula (a1-2), and the following general formula (a1-3). 【Chemical Formula 4】 (In the general formula (a1-1), R ７ and R ８ each independently represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or an alkoxy group having 1 to 3 carbon atoms. A plurality of R ７ 's, a plurality of R ８ 's may be the same or different from each other. R ９ represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or an alkoxy group having 1 to 3 carbon atoms. A plurality of R ９ 's may be the same or different from each other. * represents a bond. In the general formula (a1-2), R １０ and R １１ each independently represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or an alkoxy group having 1 to 3 carbon atoms, and a plurality of R １０ 's, and a plurality of R １１ 's may be the same or different from each other. * represents a bond. In general formula (a1-3), Z represents an alkylene group having 1 to 5 carbon atoms or a divalent aromatic group. * represents a bond.)

3. The negative-type photosensitive polymer according to Claim 2, wherein at least one of both ends is a (meth) acrylate group.

4. The negative-type photosensitive polymer according to Claim 2 or 3, containing structural units represented by the following general formula (1) and the following general formula (2). 【Chemical Formula 5】 (In the general formula (1), R １ , R ２ is synonymous with the general formula (a2), and Y is synonymous with the general formula (a1).) 【Chemical Formula 6】 (In general formula (2), Q, R ５ , R ６ , m1, m2, and X are synonymous with general formula (a3), and Y is synonymous with general formula (a1).)

5. The negative-type photosensitive polymer according to any one of Claims 2 to 4, wherein the reduction rate of the weight average molecular weight measured under the following conditions is 15% or less. (Conditions) When 400 parts by mass of γ-butyrolactone, 200 parts by mass of 4-methyltetrahydropyran, and 50 parts by mass of water are added to 100 parts by mass of the negative-type photosensitive polymer and stirred at 100 ° C for 6 hours, it is calculated by the following formula. Formula: [(Weight average molecular weight before the test - Weight average molecular weight after the test) / Weight average molecular weight before the test] × 100

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