Negative type photosensitive polymer, polymer solution, negative type photosensitive resin composition, cured film and semiconductor device

Abstract

To provide a negative type photosensitive polymer excellent in solubility to an organic solvent and capable of obtaining a cured product such as a film inhibiting hydrolysis and suppressing a deterioration of mechanical strength such as elongation.SOLUTION: A negative type photosensitive polymer is a solvent-soluble negative type photosensitive polymer including a structural unit containing an imide ring and having a group with a terminal double bond. An average value is 0.099 or less with regard to a plus electric charge (δ+) of two carbonyl carbons of the imide ring calculated with an electric charge equilibrium method.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a negative-type photosensitive polymer, a polymer solution, a negative-type photosensitive resin composition, a cured film, and a semiconductor device. [Background technology]

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

[0003] Patent Document 1 discloses a resin composition containing a polyimide resin having a specific organic group. The document describes that the resin composition is easily soluble in an alkaline developer before exposure and becomes insoluble in an alkaline developer upon exposure, and that the film shrinkage caused by curing is small, allowing a highly rectangular post-curing pattern to be obtained. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2018-070829 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, it was found that the mechanical strength, such as elongation, of the conventional polymer described in Patent Document 1 decreases due to hydrolysis. In addition, negative-type photosensitive polymers are also required to have excellent solubility in general solvents used in varnishes. [Means for solving the problem]

[0006] The present inventors have found that in a certain negative-type photosensitive polymer including a structural unit containing an imide ring, hydrolysis is suppressed when the positive charge on the carbonyl carbon of the imide ring is within a certain range, and have completed the present invention. That is, the present invention can be shown as follows.

[0007] [1] A solvent-soluble negative-type photosensitive polymer comprising a structural unit containing an imide ring and a group having a terminal double bond, A negative-type photosensitive polymer, wherein the average value of the positive charges (δ+) of the two carbonyl carbons of the imide ring is 0.099 or less, as calculated by the charge balance method. [2] The negative-type photosensitive polymer according to [1], which does not contain a fluorine atom in its molecular structure. [3] The negative type photosensitive polymer according to [1] or [2], wherein the structural unit is represented by the following general formula (1): [ka] (In the general formula (1), X represents a divalent organic group containing an aromatic group, A represents a ring structure containing two carbon atoms of the imide ring, Q represents a divalent organic group. [4] The negative-type photosensitive polymer according to [3], wherein the aromatic group contained in the divalent organic group of X in the general formula (1) is bonded to the nitrogen atom in the general formula (1) and has electron-donating groups at two ortho positions relative to the carbon atom bonded to the nitrogen atom. [5] The negative type photosensitive polymer according to [3] or [4], wherein X in the general formula (1) is a divalent group represented by the following general formula (1a) or the following general formula (1b): [ka] (In general formula (1a), R 1 ~R 4 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; R 1 and R 2 are different groups, and R 3and R 4 are different groups. X 1 represents a single bond, -SO2-, -C(=O)-, a linear or branched alkylene group having 1 to 5 carbon atoms, or a fluorenylene group. * represents a bond. In general formula (1b), R a , R b 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 R b may be the same or different. * indicates a bond.) [6] The negative type photosensitive polymer according to any one of [3] to [5], wherein X in the general formula (1) contains a divalent group represented by the following general formula (1c) which has a group having a terminal double bond: [ka] In general formula (1c), 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. 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 2 represents a single bond, -SO2-, -C(=O)-, or a straight-chain or branched alkylene group having 1 to 5 carbon atoms. * represents a bond.) [7] The negative photosensitive polymer according to any one of [1] to [5], which has a group having a terminal double bond at at least one of both ends. [8] The negative type photosensitive polymer according to any one of [3] to [7], wherein A in the general formula (1) is an aromatic ring. [9] The negative type photosensitive polymer according to any one of [3] to [8], wherein Q in the general formula (1) is a divalent group containing an imide ring.

[10] The negative type photosensitive polymer according to any one of [5] to [9], wherein the structural unit represented by the general formula (1) includes a structural unit represented by the following general formula (1-1): [ka] (In general formula (1-1), X is a divalent group represented by general formula (1a) or general formula (1b), and Y is a divalent organic group.)

[11] The negative type photosensitive polymer according to

[10] , wherein X in general formula (1-1) contains a divalent group represented by general formula (1c).

[12] The negative type photosensitive polymer according to

[10] or

[11] , wherein Y in the general formula (1-1) is a divalent organic group selected from the following general formulae (a1-1), (a1-2), (a1-3), and (a1-4): [ka] (In 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, 7 R 8 R may be the same or different. 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 9 may be the same or different. * indicates a bond. In 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, 10 R 11 may be the same or different. * indicates a bond. In general formula (a1-3), Z 1 represents an alkylene group having 1 to 5 carbon atoms or a divalent aromatic group. * represents a bond. In general formula (a1-4), Z 2indicates a divalent aromatic group. * indicates a bond.)

[13] The negative type photosensitive polymer according to any one of [1] to

[12] , which is soluble in a solvent selected from N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, γ-butyrolactone (GBL), and cyclopentanone at a concentration of 5 mass % or more.

[14] The negative type photosensitive polymer according to any one of [1] to

[13] , which is soluble in γ-butyrolactone (GBL) at a concentration of 5% by mass or more.

[15] The negative type photosensitive polymer according to any one of [1] to

[14] , wherein a reduction rate of the weight average molecular weight measured under the following conditions is 15% or less. (conditions) The viscosity is calculated according to the following formula when 100 parts by mass of the negative photosensitive polymer is added with 400 parts by mass of γ-butyrolactone, 200 parts by mass of 4-methyltetrahydropyran, and 50 parts by mass of water and stirred at 100° C. for 6 hours. Formula: [(Weight average molecular weight before test - Weight average molecular weight after test) / Weight average molecular weight before test] x 100

[16] A polymer solution comprising the negative type photosensitive polymer according to any one of [1] to

[15] .

[17] (A) a negative type photosensitive polymer according to any one of [1] to

[15] , (B) a crosslinking agent containing a multifunctional (meth)acrylate; (C) a photopolymerization initiator; A negative type photosensitive resin composition comprising:

[18] A cured film comprising a cured product of the negative photosensitive resin composition described in

[17] .

[19] A semiconductor device comprising a resin film containing a cured product of the negative photosensitive resin composition according to

[17] .

[0008] In the present invention, the term "positive charge (δ+)" refers to the positive charge of a specific atom calculated by the charge equilibration method (Charge (Q) Equilibration (Eq): QEq), expressed as delta plus (δ+).

[0009] The charge balancing method is as follows. When atoms form bonds, they change their electron density until their electronegativity becomes equal (equilibrium is reached). Initially, the charge on all atoms in a molecule starts out at zero, and electrons flow from less electronegative atoms to more electronegative atoms. As electrons accumulate on atoms, their electronegativity decreases, and when equilibrium is reached, the electronegativity of each atom becomes equal and the flow of electrons stops. The charge balance method performs these repeated calculations to calculate the charges on atoms in a molecule, allowing a positive charge on a given atom to be expressed as delta plus (δ+) and a negative charge on a given atom to be expressed as delta minus (δ-).

[0010] The negative photosensitive polymer of the present invention is dissolved in a solvent and used as a varnish. "Soluble in solvent" means that it is soluble in any of the common solvents used for varnishes. Common solvents include N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, γ-butyrolactone (GBL), cyclopentanone, etc. The term "soluble" means that the negative photosensitive polymer of the present invention dissolves in an amount of 5% by mass or more in 100% by mass of these specific solvents. Effect of the Invention

[0011] According to the present invention, it is possible to provide a negative-type photosensitive polymer which has excellent solubility in organic solvents and which can give a cured product such as a film in which hydrolysis is suppressed and deterioration in mechanical strength such as elongation is suppressed, and a negative-type photosensitive resin composition containing the polymer. [Brief description of the drawings]

[0012] [Figure 1] 1 is a schematic cross-sectional view of a semiconductor device according to an embodiment of the present invention; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, the embodiments of the present invention will be described with reference to the drawings. In all drawings, the same components are denoted by the same reference numerals, and the description will be omitted as appropriate. For example, "1 to 10" means "1 or more" to "10 or less" unless otherwise specified.

[0014] The solvent-soluble negative-type photosensitive polymer of the present embodiment is a polymer including a structural unit containing an imide ring and having a group having a terminal double bond, The average value of the positive charges (δ+) of the two carbonyl carbons of the imide ring, calculated by the charge balance method, is 0.099 or less, preferably 0.098 or less, more preferably 0.097 or less, and further preferably 0.095 or less. This makes it possible to provide a cured product such as a film that has excellent solubility in organic solvents and is inhibited from hydrolysis, thereby inhibiting a decrease in mechanical strength such as elongation. The lower limit of the average value of the positive charges (δ+) of the two carbonyl carbons of the imide ring is not particularly limited, but is preferably 0.070 or more, more preferably 0.080 or more, and even more preferably 0.085 or more. When the average value is equal to or more than the above lower limit, it is considered that coloring caused by bias in charges can be suppressed, and a decrease in sensitivity can be suppressed when the negative type photosensitive polymer of the present embodiment is used as a photosensitive resin composition. The upper limit and the lower limit can be combined in any way.

[0015] The negative photosensitive polymer of the present embodiment can provide a cured product such as a film that has excellent solubility in organic solvents and is inhibited from hydrolyzing, thereby inhibiting a decrease in mechanical strength such as elongation.

[0016] The solvent-soluble negative-type photosensitive polymer of this embodiment may contain fluorine atoms in its molecular structure as long as the average value of the positive charges (δ+) of the carbonyl carbons falls within a predetermined range and the effects of the present invention are not adversely affected. However, it is preferable that the molecular structure does not contain fluorine atoms with strong electron-withdrawing properties.

[0017] The imide ring-containing structural unit contained in the solvent-soluble negative-type photosensitive polymer can be represented by the following general formula (1): .

[0018] [ka]

[0019] In the general formula (1), A represents a ring structure containing two carbon atoms of an imide ring, and is preferably an aromatic ring such as a benzene ring or a naphthalene ring.

[0020] In general formula (1), Q represents a divalent organic group, and is preferably a divalent group containing an imide ring. In the general formula (1), X represents a divalent organic group containing an aromatic group. In X of the general formula (1), the aromatic group contained in the divalent organic group is preferably bonded to the nitrogen atom in the general formula (1). The two ortho positions to the carbon atom of the aromatic group bonded to the nitrogen atom are more preferably provided with electron donating groups, and even more preferably asymmetric electron donating groups. Examples of the electron donating groups include a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, and an alkoxy group having 1 to 3 carbon atoms. The divalent organic group for X includes a divalent group represented by the following general formula (1a) or the following general formula (1b). X can contain at least one divalent group represented by general formula (1a) or at least one divalent group represented by general formula (1b), and can also contain a combination of these groups.

[0021] [ka]

[0022] In general formula (1a), R 1 ~R 4 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; R 1 and R 2are different groups, and R 3 and R 4 are different groups.

[0023] X 1 represents a single bond, -SO2-, -C(=O)-, a linear or branched alkylene group having 1 to 5 carbon atoms, or a fluorenylene group. * represents a bond.

[0024] In general formula (1b), R a , R b 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 R b may be the same or different. * indicates a bond. The two ortho positions (R 1 and R 2 (or R 3 and R 4 In terms of the effects of the present invention, it is preferable that X has a predetermined electron-donating group in formula (1), and X in formula (1) is more preferably a divalent group represented by formula (1a).

[0025] When the side chain has a group having a terminal double bond, X may contain a divalent group represented by the following general formula (1c).

[0026] [ka]

[0027] In the general formula (1c), 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.

[0028] Examples of the divalent to tetravalent organic group having 1 to 10 carbon atoms include an ester group, a divalent to tetravalent aliphatic hydrocarbon group having 1 to 10 carbon atoms, and a divalent to tetravalent alicyclic hydrocarbon group having 3 to 10 carbon atoms. These hydrocarbon groups may contain a heteroatom such as oxygen, nitrogen, or sulfur atom, and may have an ester bond, a thioester bond, a urethane bond, a thiourethane bond, a urea bond, or the like in the structure.

[0029] 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 2 represents a single bond, -SO2-, -C(=O)-, or a linear or branched alkylene group having 1 to 5 carbon atoms. * represents a bond.

[0030] Specifically, the structural unit represented by the general formula (1) preferably includes a structural unit represented by the following general formula (1-1).

[0031] [ka]

[0032] In the general formula (1-1), X can be a divalent group represented by the general formula (1a) or (1b) above.

[0033] The group having a terminal double bond can be provided at least one of both ends of the solvent-soluble negative photosensitive polymer or on a side chain, and it is also preferable to provide it on both ends. When the side chain has a group having a terminal double bond, X can contain a divalent group represented by the general formula (1c) above.

[0034] In the general formula (1-1), Y is a divalent organic group. The divalent organic group for Y can be selected from the following general formula (a1-1), (a1-2), (a1-3), and (a1-4).

[0035] [ka]

[0036] In 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, 7 R 8 They may be the same or different. R 7 and R 8 From the viewpoint of the effects of the present invention, is preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and more preferably a hydrogen atom.

[0037] 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 9 They may be the same or different. R 9 From the viewpoint of the effects of the present invention, is preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and more preferably a hydrogen atom. * indicates a bond.

[0038] In 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, 10 R 11 They may be the same or different.

[0039] R 10 and R 11 From the viewpoint of the effects of the present invention, R is preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and more preferably R10 At least one of and R 11 At least one of R is an alkyl group having 1 to 3 carbon atoms, and more preferably, three R 10 is an alkyl group having 1 to 3 carbon atoms, and one R 10 is a hydrogen atom and three R 11 is an alkyl group having 1 to 3 carbon atoms, and one R 11 is a hydrogen atom, and particularly preferably, three R 10 is a methyl group and one R 10 is a hydrogen atom and three R 11 is a methyl group and one R 11 is a hydrogen atom. * indicates a bond.

[0040] In general formula (a1-3), Z 1 represents an alkylene group having 1 to 5 carbon atoms or a divalent aromatic group. * represents a bond.

[0041] In general formula (a1-4), Z 2 represents a divalent aromatic group, preferably a divalent benzene ring. * represents a bond.

[0042] The negative photosensitive polymer of this embodiment can contain at least one structural unit selected from a structural unit (1-1a) represented by the following general formula (1-1a) and a structural unit (1-1b) represented by the following general formula (1-1b).

[0043] [ka]

[0044] In general formula (1-1a), R 1 ~R 4 , X 1 has the same meaning as in formula (1a), and Y has the same meaning as in formula (1-1).

[0045] [ka]

[0046] In general formula (1-1b), R a and R b has the same meaning as in formula (1b), and Y has the same meaning as in formula (1-1).

[0047] The group having a terminal double bond may be provided at least at one of both ends of the solvent-soluble negative photosensitive polymer or on a side chain. When the group having a terminal double bond is provided on a side chain, the polymer may include a structural unit (1-1c) represented by the following general formula (1-1c).

[0048] [ka]

[0049] In general formula (1-1c), R 5 , R 6 , Q, m1, m2, X 2 has the same meaning as in formula (1c), and Y has the same meaning as in formula (1-1).

[0050] In this embodiment, for example, in a negative photosensitive polymer containing a structural unit represented by the general formula (1-1), the average value of the positive charges (δ+) of the two carbonyl carbons of the imide ring is measured as follows.

[0051] The average value of δ+ of two carbonyl carbons in the imide ring contained in the compound represented by the following general formula (1-1′), measured under the following conditions, is calculated. [conditions] The compound represented by the general formula (1-1') is measured by a charge equilibration method using the software HSPiP (ver. 5.3), and the δ+ of the two carbonyl carbons of the imide ring contained in the compound is calculated as an average.

[0052] [ka]

[0053] In formula (1-1'), Y has the same meaning as in formula (1-1). ’is a monovalent group represented by the following general formula (1a-1) or the following general formula (1b-1).

[0054] [ka]

[0055] In general formula (1a-1), R 1 ~R 4 , X 1 has the same meaning as in formula (1a). * indicates a bond. In formula (1b-1), R a , R b has the same meaning as in formula (1b). * indicates a bond.

[0056] When the negative-type photosensitive polymer containing the structural unit represented by the general formula (1-1) contains a plurality of groups as X, the average value of δ+ is calculated for each possible combination, and a weighted average is taken according to the amount of the compound charged, to calculate the average value of the positive charges (δ+) of the two carbonyl carbons of the imide ring.

[0057] Specifically, when a negative-type photosensitive polymer containing a structural unit represented by general formula (1-1) contains a structural unit (1-1a) having a group represented by general formula (1a) as X and a structural unit (1-1b) having a group represented by general formula (1b) as X, The compound represented by the general formula (1-1') having a group of the general formula (1a-1) is measured by the charge equilibration method using the software HSPiP (ver5.3), and the average value (1) is obtained by averaging the δ+ of the two carbonyl carbons of the imide ring contained in the compound. The compound represented by the general formula (1-1') having a group of the general formula (1b-1) is similarly measured, and the average value (2) is obtained by averaging the δ+ of the two carbonyl carbons of the imide ring contained in the compound. Then, when the sum of the number of moles (1) of the structural unit (1-1a) and the number of moles (2) of the structural unit (1-1b) is set to 100, δ+ is calculated by the following formula. Formula: [average value of δ+(1) × mole fraction(1) + average value of δ+(2) × mole fraction(2)] / 100

[0058] Furthermore, when a group having a terminal double bond is provided on the side chain of the negative photosensitive polymer, X ’ may contain a monovalent group represented by the following general formula (1c-1).

[0059] [ka]

[0060] In general formula (1c-1), R 5 , R 6 , Q, m1, m2, X 2 has the same meaning as general formula (1c). For example, when a negative-type photosensitive polymer containing a structural unit represented by general formula (1-1) contains a structural unit (1-1a) having a group represented by general formula (1a) as X, a structural unit (1-1b) having a group represented by general formula (1b) as X, and a structural unit (1-1c) having a group represented by general formula (1c) as X, The compound represented by the general formula (1-1') having a group represented by the general formula (1a-1) is measured by the charge equilibration method using the software HSPiP (ver5.3), and the average value (1) is obtained by averaging the δ+ of the two carbonyl carbons of the imide ring contained in the compound. The compound represented by the general formula (1-1') having a group represented by the general formula (1b-1) is measured in the same manner, and the average value (2) is obtained by averaging the δ+ of the two carbonyl carbons of the imide ring contained in the compound. Furthermore, the compound represented by the general formula (1-1') having a group represented by the general formula (1c-1) is measured in the same manner, and the average value (3) is obtained by averaging the δ+ of the two carbonyl carbons of the imide ring contained in the compound. Then, when the sum of the number of moles (1) of the structural unit (1-1a), the number of moles (2) of the structural unit (1-1b), and the number of moles (3) of the structural unit (1-1c) is set to 100, δ+ is calculated using the following formula. Formula: [average value of δ+(1) × mole fraction(1) + average value of δ+(2) × mole fraction(2) + average value of δ+(3) × mole fraction(3)] / 100

[0061] Even when the negative-type photosensitive polymer containing the structural unit represented by the general formula (1-1) contains four or more types of groups as X, the average value of δ+ is calculated for each possible combination in the same manner as above, and a weighted average is taken according to the amount of charge to calculate the average value of the positive charges (δ+) of the two carbonyl carbons of the imide ring of the negative-type photosensitive polymer.

[0062] When the negative photosensitive polymer of the present embodiment contains the above structural unit and has a structure in which a group having a terminal double bond is provided in a side chain of the negative photosensitive polymer, it may further contain a portion of the following structural unit.

[0063] [ka]

[0064] In these general formulas, R 5 , R 6 , Q, m1, m2, X 2 has the same meaning as in formula (1c), and Y has the same meaning as in formula (1-1). In this embodiment, the negative photosensitive polymer preferably has a group having a terminal double bond at at least one of both ends, and more preferably the group is a (meth)acrylate group. By including such a group, the mechanical strength such as elongation is superior. The presence of a (meth)acrylate group means 1 It can be analyzed by H-NMR.

[0065] Specifically, when the negative-type photosensitive polymer containing the divalent group represented by the general formula (1c) has a group having a terminal double bond at at least one of its two ends, it preferably has at least one of the terminal structures (a4) to (a13) represented by the following general formulae (a4) to (a13), and more preferably has the terminal structure (a4). On the other hand, the negative-type photosensitive polymer not containing a divalent group represented by the general formula (1c) preferably has at least one of the terminal structures (a4) to (a6) represented by the following general formulae (a4) to (a6) at at least one of both ends, and more preferably has the terminal structure (a4). [ka] TIFF2024019205000019.tif176153

[0066] In the general formula (a4), Q has the same meaning as in the general formula (1c), and Y has the same meaning as in the general formula (1-1). 7 represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or an alkoxy group having 1 to 3 carbon atoms. m3 represents an integer of 1 to 3. * represents a bond. In formula (a5), Q has the same meaning as in formula (1c); 1 , R 1 ~R 4 R has the same meaning as in general formula (1a). 7 and m3 has the same meaning as in formula (a4). * indicates a bond. In formula (a6), Q has the same meaning as in formula (1c), R a , R b R has the same meaning as in general formula (1b). 7 and m3 has the same meaning as in formula (a4). * indicates a bond. In general formulas (a7) to (a13), Q, R 5 , R 6 , m1, m2, and X 2 R has the same meaning as in general formula (1c). 7 and m3 has the same meaning as in formula (a4). * indicates a bond.

[0067] The weight average molecular weight of the negative photosensitive polymer of this embodiment is 5,000 to 200,000, and preferably 10,000 to 100,000.

[0068] In the negative photosensitive polymer of the present embodiment, hydrolysis is suppressed, and the negative photosensitive polymer and the negative photosensitive resin composition containing the negative photosensitive polymer can give a cured product such as a film having excellent mechanical strength such as elongation.

[0069] In addition, since the negative photosensitive polymer of the present embodiment has excellent solubility in solvents and does not need to be made into a varnish in the precursor state, a varnish containing the negative photosensitive polymer can be prepared, and a cured product such as a film can be obtained from the varnish.

[0070] <Method of manufacturing negative-type photosensitive polymer> [First embodiment] A method for producing a negative-type photosensitive polymer having a group with a terminal double bond in the side chain is described. For example, a method for producing a negative-type photosensitive polymer having the structural unit (1-1a) and / or the structural unit (1-1b) and the structural unit (1-1c) can be carried out by the following method:

[0071] A step 1 of imidizing an acid anhydride (i) represented by the following general formula (i), a diamine (ii) represented by the following general formula (ii) and / or a diamine (iii) represented by the following general formula (iii), and a bisaminophenol (iv) represented by the following general formula (iv) at a temperature of 100° C. or higher and 250° C. or lower;

[0072] and step 2 of reacting a compound having a (meth)acrylate group with the hydroxyl group of the structural unit derived from bisaminophenol (iv) of general formula (iv) of the polymer obtained in step 1 to introduce a group containing a (meth)acrylate group. According to this embodiment, a negative-type photosensitive polymer having excellent solvent solubility can be synthesized by a simple method.

[0073] [ka]

[0074] In formula (i), Y has the same meaning as in formula (1-1), and is preferably selected from the groups represented by formulas (a1-1), (a1-2), (a1-3) and (a1-4).

[0075] [ka]

[0076] In general formula (ii), R 1 ~R 4 , X 1 has the same meaning as general formula (1a).

[0077] [ka]

[0078] In general formula (iii), R a , R b has the same meaning as general formula (1b).

[0079] [ka]

[0080] In general formula (iv), X 2 has the same meaning as general formula (1c). 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 an acid anhydride or aromatic amine as an end-capping agent.

[0081] Examples of acid anhydrides as end-capping agents include phthalic anhydride, maleic anhydride, and nadic anhydride, and examples of aromatic amines include p-methylaniline, p-methoxyaniline, and p-phenoxyaniline. The amount of acid anhydrides or aromatic amines added as end-capping agents is preferably 5 mol% or less. If the amount exceeds 5 mol%, the molecular weight of the resulting polyhydroxyimide is significantly reduced, causing problems in heat resistance and mechanical properties.

[0082] The equivalent ratio of the acid anhydride (i), the diamine (ii) and / or the diamine (iii) and the bisaminophenol (iv) in the imidization reaction in step 1 is an important factor that determines the molecular weight of the resulting polymer. It is generally 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 relatively high molecular weight. In the present invention, the equivalent ratio of the acid anhydride (i), the diamine (ii) and / or the diamine (iii) and the bisaminophenol (iv) used is not particularly limited, but it is preferable that the equivalent ratio of the diamine (ii) and / or the diamine (iii) and the bisaminophenol (iv) to the acid anhydride (i) is in the range of 0.70 to 1.30. If the equivalent ratio is within the above range, the mechanical strength and production stability are excellent.

[0083] From the viewpoint of improving mechanical properties, even if the equivalent ratio of diamine (ii) and / or diamine (iii) and bisaminophenol (iv) to acid anhydride (i) is outside the above range, the apparent molecular weight can be increased by crosslinking the resin at its side chains. Step 1 (imidization reaction step) can be carried out in an organic solvent by a known method.

[0084] 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, and one or more of these may be used in combination. In this case, a non-polar solvent that is compatible with the above aprotic polar solvent may be mixed and used. Examples of the non-polar solvent include aromatic hydrocarbons such as toluene, ethylbenzene, xylene, mesitylene, and solvent naphtha, and ether solvents such as cyclopentyl methyl ether. The ratio of the non-polar solvent in the mixed solvent can be arbitrarily set according to the resin properties such as the stirring device capacity and the solution viscosity, as long as the solubility of the solvent is reduced and the polyamic acid resin obtained by the reaction is not precipitated.

[0085] The reaction temperature is from 0°C to 100°C, preferably from 20°C to 80°C, for about 30 minutes to 2 hours, and then from 100°C to 250°C, preferably from 120°C to 200°C, for about 1 to 5 hours.

[0086] Polyhydroxyimide having the structural unit (1-1a) and / or the structural unit (1-1b) and the structural unit (1-1d) represented by the following general formula (1-1d) can be obtained by step 1. Note that, although the polyhydroxyimide can be purified by a known method in step 1, steps 1 and 2 can be carried out continuously without purifying the obtained polyhydroxyimide by improving the dehydration efficiency in the polymerization.

[0087] [ka]

[0088] In general formula (1-1d), X 2 has the same meaning as in formula (1c), and Y has the same meaning as in formula (1-1), and is preferably selected from the groups represented by formula (a1-1), (a1-2), (a1-3) or (a1-4). 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 groups introduced into the negative photosensitive polymer (A) react with the crosslinking agent (B) described below in the exposure step, making the exposed areas insoluble in organic solvents.

[0089] Examples of compounds having a (meth)acrylate group include 2-isocyanatoethyl (meth)acrylate, 2-(2-(meth)acryloyloxyethyloxy)ethyl isocyanate, 1,1-(bisacryloyloxymethyl)ethyl isocyanate, glycidyl methacrylate, and 4-hydroxybutyl acrylate glycidyl ether.

[0090] To introduce a crosslinking group containing a (meth)acrylate group into polyhydroxyimide, polyhydroxyimide and a compound containing a (meth)acrylate group are mixed in an organic solvent and reacted at 60° C. to 150° C. for about 2 to 10 hours. The reaction can be carried out at normal pressure, although there is no particular limitation.

[0091] The compound having a (meth)acrylate group can be appropriately selected according to the amount of crosslinking group to be introduced into the polyhydroxyimide, and can be added, for example, in an amount of 0.8 to 3.0 times the molar amount of the hydroxyl group of the polyhydroxyimide, and preferably 2.0 to 3.0 times the molar amount. In addition, when the polyhydroxyimide has a group capable of introducing a crosslinking group, the group can be added to the molar amount.

[0092] 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, and one or more of these may be used in combination. In this case, a non-polar solvent that is compatible with the above aprotic polar solvent may be mixed and used. Examples of the non-polar solvent include aromatic hydrocarbons such as toluene, ethylbenzene, xylene, mesitylene, and solvent naphtha, and ether solvents such as cyclopentyl methyl ether.

[0093] In the reaction, a base such as triethylamine or 1,1,3,3-tetramethylguanidine can be added. By the step 2, a negative photosensitive polymer having the structural unit (1-1a) and / or the structural unit (1-1b) and the structural unit (1-1c) can be obtained.

[0094] In step 2, the reaction solution containing the polyhydroxyimide obtained in step 1 can be purified by reprecipitation or the like to obtain a polyhydroxyimide, but the reaction solution in step 1 can be used in step 2 as it is.

[0095] By the above-mentioned manufacturing method of this embodiment, a reaction solution containing the negative type photosensitive polymer of this embodiment can be obtained, which can be further diluted with an organic solvent or the like as necessary and used as a polymer solution (varnish for coating). 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.

[0096] In addition, the reaction solution can be poured into a poor solvent to reprecipitate the negative photosensitive polymer, remove unreacted monomers, and then dry and solidify it, which can then be dissolved in an organic solvent again and used as a purified product. In particular, in applications where impurities or foreign matter are a problem, it is preferable to dissolve it in an organic solvent again and filter it to make a purified varnish.

[0097] [Second embodiment] A method for producing a negative-working photosensitive polymer having a group with a terminal double bond at at least one of its two termini is described.

[0098] The negative type photosensitive polymer can be produced by the same method as in the first embodiment, except that the bisaminophenol (iv) represented by the general formula (iv) is not used.

[0099] In this embodiment, the equivalent ratio of the acid anhydride (i) to the diamine (ii) and / or diamine (iii) used is not particularly limited, but it is preferable that the equivalent ratio of the diamine (ii) and / or diamine (iii) to the acid anhydride (i) is in the range of 0.70 to 1.30. If it is less than 0.70, the molecular weight is low and the polymer becomes brittle, resulting in a weakened mechanical strength. If it exceeds 1.30, the molecular weight is low and the polymer becomes brittle, resulting in a weakened mechanical strength. In other words, if the equivalent ratio is in the above range, the polymer has excellent mechanical strength and excellent production stability.

[0100] [Characteristics of negative-type photosensitive polymers] The negative photosensitive polymer of this embodiment has excellent solvent solubility, and can be dissolved in γ-butyrolactone (GBL) at a concentration of 5% by mass or more. The negative photosensitive polymer of this embodiment is soluble in a solvent and can therefore be suitably used as a polymer solution (varnish).

[0101] The negative photosensitive polymer of this embodiment has excellent hydrolysis resistance, and the rate of decrease in weight average molecular weight measured under the following conditions is 15% or less, preferably 12% or less. (conditions) The viscosity is calculated according to the following formula when 100 parts by mass of the negative photosensitive polymer is added with 400 parts by mass of γ-butyrolactone, 200 parts by mass of 4-methyltetrahydropyran, and 50 parts by mass of water and stirred at 100° C. for 6 hours. Formula: [(Weight average molecular weight before test - Weight average molecular weight after test) / Weight average molecular weight before test] x 100

[0102] When the negative photosensitive polymer of this embodiment has a reduction rate of the weight average molecular weight within the above range, it is possible to obtain a cured product such as a film having excellent mechanical strength such as elongation.

[0103] A preferred example of the composition of the negative photosensitive polymer of this embodiment is shown in Table A below.

[0104] [Table 1]

[0105] MED-J: 4,4-diamino-3,3-diethyl-5,5-dimethyldiphenylmethane TMDA: A mixture of 1-(4-aminophenyl)-1,3,3-trimethylphenylindan-6-amine and 1-(4-aminophenyl)-1,3,3-trimethylphenylindan-5-amine BTFL: 9,9-bis(3-methyl-4-aminophenyl)fluorene BAPA: 2,2-bis(3-amino-4-hydroxyphenyl)propane ·TMPBP-TME: 4-[4-(1,3-dioxoisobenzofuran-5-ylcarbonyloxy)-2,3,5-trimethylphenyl]-2,3,6-trimethylphenyl 1,3-dioxoisobenzofuran-5-carboxylate TMHQ: p-phenylene bis(trimellitate anhydride) ·AOI: 2-isocyanatoethyl acrylate MOI: 2-isocyanatoethyl methacrylate

[0106] <Negative-type photosensitive resin composition> The negative type photosensitive resin composition of the present embodiment contains (A) the above-mentioned negative type photosensitive polymer, (B) a crosslinking agent containing a polyfunctional (meth)acrylate, and (C) a photopolymerization initiator.

[0107] [Crosslinking agent (B)] The crosslinking agent (B) includes a polyfunctional (meth)acrylate. The polyfunctional (meth)acrylate is a compound having two or more (meth)acryloyl groups, and any conventionally known compound can be used as long as it can exert the effects of the present invention. In this embodiment, the (meth)acrylic group refers to an acrylic group or a methacrylic group.

[0108] Specific examples of polyfunctional (meth)acrylates include difunctional (meth)acrylates such as diethylene glycol di(meth)acrylate, polyethylene glycol #200 di(meth)acrylate, and polyethylene glycol #400 di(meth)acrylate, trifunctional (meth)acrylates such as trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, and ethoxylated isocyanuric acid triacrylate, tetrafunctional (meth)acrylates such as pentaerythritol tetra(meth)acrylate and ditrimethylolpropane tetra(meth)acrylate, hexafunctional (meth)acrylates such as dipentaerythritol hexa(meth)acrylate, octafunctional (meth)acrylates such as tripentaerythritol octa(meth)acrylate, and decafunctional (meth)acrylates such as tetrapentaerythritol deca(meth)acrylate. Of these, one or more may be used.

[0109] 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 negative photosensitive polymer (A) can be set to 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, and preferably 3 parts by mass or more and 15 parts by mass or less. By being in this range, the elongation is further improved.

[0110] [Photopolymerization initiator (C)] As the photopolymerization initiator (C), for example, a photoradical generator can be used. The photoradical generator contains a photoradical generator that generates radicals when irradiated with active light such as ultraviolet light and functions as a photopolymerization initiator for the negative type photosensitive polymer (A) described above.

[0111] Examples of the photoradical generator include an alkylphenone type initiator, an oxime ester type initiator, and an acylphosphine oxide type initiator. 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-trimethylphenyl) ... Examples of the suitable oxime include 1-[4-(phenylthio)-phenyl phosphine oxide, 1,2-octanedione, 1-[4-(phenylthio)-, 2-(O-benzoyl oxime)], ethanone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-, 1-(0-acetyl oxime), 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), and NCI-930 (ADEKA Corporation). Any one or more of these can be used.

[0112] 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 superior exposure sensitivity, oxime ester-type initiators are preferred.

[0113] The amount of the polymerization initiator (C) added is not particularly limited, but is preferably about 0.3 to 20 mass% of 100 mass% of the non-volatile components excluding the solvent of the negative photosensitive resin composition, more preferably about 0.5 to 15 mass%, and even more preferably about 1 to 10 mass%. By setting the amount of the polymerization initiator (C) added within the above range, the patterning property of the photosensitive resin layer containing the negative photosensitive resin composition can be improved, and the long-term storage property of the negative photosensitive resin composition can be improved.

[0114] (solvent) The negative photosensitive resin composition according to this embodiment may contain a solvent, which allows a uniform photosensitive resin film to be formed on the surface of various substrates.

[0115] The solvent is preferably an organic solvent, specifically, one or more of ketone-based solvents, ester-based solvents, ether-based solvents, alcohol-based solvents, lactone-based solvents, carbonate-based solvents, etc. can be used.

[0116] Examples of solvents 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 mixtures thereof. The amount of the solvent used is not particularly limited, and is used in an amount such that the concentration of non-volatile components becomes, for example, 10 to 70% by mass, and preferably 15 to 60% by mass.

[0117] (Surfactant) The negative photosensitive resin composition according to this embodiment may further contain a surfactant.

[0118] The surfactant is not limited, and specific examples thereof include polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, and polyoxyethylene oleyl ether; polyoxyethylene aryl ethers such as polyoxyethylene octylphenyl ether and polyoxyethylene nonylphenyl ether; nonionic surfactants such as polyoxyethylene dialkyl esters such as polyoxyethylene dilaurate and polyoxyethylene distearate; F-TOP EF301, F-TOP EF303, and F-TOP EF352 (manufactured by Shin-Akita Kasei Co., Ltd.), Megafack F171, Megafack F172, Megafack F173, Megafack F177, Megafack F444, Megafack F470, Examples of the fluorine-based surfactant include those commercially available under the names 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 Co., 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.); and (meth)acrylic acid-based copolymer Polyflow No. 57, 95 (manufactured by Kyoeisha Chemical Co., Ltd.).

[0119] Among these, it is preferable to use a fluorine-based surfactant having a perfluoroalkyl group. As the fluorine-based surfactant having a perfluoroalkyl group, it is preferable to use one or more selected from the above specific examples: 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.).

[0120] As the surfactant, silicone surfactants (such as polyether-modified dimethylsiloxanes) can also be preferably used. Specific examples of silicone surfactants include the SH series, SD series, and ST series from Dow Corning Toray Co., Ltd., the BYK series from BYK Japan Co., Ltd., the KP series from Shin-Etsu Chemical Co., Ltd., the Disfoam (registered trademark) series from NOF Corporation, and the TSF series from Toshiba Silicones Co., Ltd.

[0121] The upper limit of the surfactant content in the negative photosensitive resin composition is preferably 1 mass % (10,000 ppm) or less, more preferably 0.5 mass % (5,000 ppm) or less, and even more preferably 0.1 mass % (1,000 ppm) or less, based on the entire negative photosensitive resin composition (including the solvent).

[0122] 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 obtaining a sufficient effect of the surfactant, the content is, for example, 0.001 mass % (10 ppm) or more with respect to the entire negative photosensitive resin composition (including the solvent). By appropriately adjusting the amount of the surfactant, it is possible to improve the coatability and the uniformity of the coating film while maintaining other performance properties.

[0123] (Antioxidants) The negative photosensitive resin composition according to this embodiment may further contain an antioxidant. As the antioxidant, one or more selected from a phenol-based antioxidant, a phosphorus-based antioxidant, and a thioether-based antioxidant can be used. The antioxidant can suppress oxidation of the resin film formed by the negative photosensitive resin composition.

[0124] 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], and 1,6-hexanediol-bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate]. ester], 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] t], 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-butyl-6-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)sa 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-methylphenylacrylate, 2,4-dimethyl-6-(1-methylcyclohexyl, styrenated phenol, 2,4-bis((octylthio)methyl)-5-methylphenol, etc.

[0125] 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'-biphenylene diphosphonite, 3,5-di-t-butyl-4-hydroxybenzylphosphonate-diethyl ester, bis-(2,6-dicumylphenyl)pentaerythritol diphosphite, 2,2-methylene biphosphonate, and bis(2,6-dicumylphenyl)pentaerythritol diphosphite. Examples of suitable phosphite include bis(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, and bis(2,6-di-t-butyl-4-octadecyloxycarbonylethylphenyl)pentaerythritol diphosphite.

[0126] Examples of thioether antioxidants include dilauryl-3,3'-thiodipropionate, bis(2-methyl-4-(3-n-dodecyl)thiopropionyloxy)-5-t-butylphenyl)sulfide, distearyl-3,3'-thiodipropionate, and pentaerythritol-tetrakis(3-lauryl)thiopropionate.

[0127] (Adhesion aid) The negative photosensitive resin composition according to this embodiment may further contain an adhesion assistant.

[0128] As the adhesion aid, for example, a silane coupling agent such as aminosilane, epoxysilane, (meth)acrylicsilane, mercaptosilane, vinylsilane, ureidosilane, acid anhydride functional silane, sulfidesilane, etc. can be used. The silane coupling agent may be used alone or in combination of two or more. Among these, epoxysilane (i.e., a compound containing both an epoxy moiety and a group that generates a silanol group by hydrolysis in one molecule) or acid anhydride functional silane (i.e., a compound containing both an acid anhydride group and a group that generates a silanol group by hydrolysis in one molecule) is preferred.

[0129] Examples of aminosilanes 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, and N-phenyl-γ-aminopropyltrimethoxysilane.

[0130] Examples of epoxy silanes include γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, and γ-glycidylpropyltrimethoxysilane.

[0131] Examples of the acrylic silane include γ-(methacryloxypropyl)trimethoxysilane, γ-(methacryloxypropyl)methyldimethoxysilane, and γ-(methacryloxypropyl)methyldiethoxysilane. An example of the mercaptosilane is 3-mercaptopropyltrimethoxysilane.

[0132] Examples of vinyl silanes include vinyl tris(β-methoxyethoxy) silane, vinyl triethoxy silane, and vinyl trimethoxy silane. An example of the ureidosilane is 3-ureidopropyltriethoxysilane.

[0133] An example of an acid anhydride functional silane is a product manufactured by Shin-Etsu Chemical Co., Ltd. under the trade name X-12-967C (compound name: 3-trimethoxysilylpropylsuccinic anhydride).

[0134] Examples of sulfide silanes include bis(3-(triethoxysilyl)propyl) disulfide and bis(3-(triethoxysilyl)propyl) tetrasulfide. The amount of the adhesion aid added is not particularly limited, but is usually 0.1 to 5 mass %, and preferably 0.5 to 3 mass %, of the total solid content of the negative photosensitive resin composition.

[0135] (Preparation of negative type photosensitive resin composition) The method for preparing the negative photosensitive resin composition in this embodiment is not limited, and any known method can be used depending on the components contained in the negative photosensitive resin composition. For example, the above components can be mixed and dissolved in a solvent to prepare the composition.

[0136] (cured film) The negative type photosensitive resin composition according to this embodiment is used by applying the negative type photosensitive resin composition to a surface comprising a metal such as Al or Cu, then pre-baking to dry and form a resin film, then exposing and developing to pattern the resin film into a desired shape, and then heat-treating the resin film to harden it and form a hardened film.

[0137] In the case of producing the permanent film, the pre-baking conditions can be, for example, a heat treatment at a temperature of 90° C. to 130° C. for 30 seconds to 1 hour, and the heat treatment conditions can be, for example, a heat treatment at a temperature of 150° C. to 250° C. for 30 minutes to 10 hours, preferably at about 170° C. for 1 to 6 hours.

[0138] The film obtained from the negative photosensitive resin composition of this embodiment has a maximum elongation of 15 to 200%, preferably 20 to 150%, and an average elongation of 10 to 150%, preferably 15 to 120%, as measured by a tensile test using a Tensilon tester.

[0139] The film obtained from the negative photosensitive resin composition of this embodiment preferably has a tensile strength of 20 MPa or more, more preferably 30 to 300 MPa, as measured by a tensile test using a Tensilon tester.

[0140] Furthermore, since the negative-type photosensitive resin composition of the present embodiment contains the negative-type photosensitive polymer (A) having excellent hydrolysis resistance, even after a HAST test (unsaturated pressurized steam test) is performed for 96 hours under conditions of a temperature of 130°C and a relative humidity of 85% RH, the rate of decrease in elongation (maximum value, average value) represented by the following formula is 20% or less, preferably 15% or less, and more preferably 12% or less. [(Elongation before test - Elongation after test) / Elongation before test)] x 100 The negative photosensitive resin composition of this embodiment has excellent low-temperature curing properties.

[0141] For example, the negative type photosensitive resin composition of the present embodiment can be cured at 170°C for 4 hours to obtain a cured product having a glass transition temperature (Tg) of 200°C or higher, preferably 210°C or higher, and more preferably 220°C or higher.

[0142] 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 modulus E′ of 2.0 GPa or more, preferably 2.5 GPa or more, and more preferably 3.0 GPa or more at 30° C. Furthermore, the storage modulus E′ of 0.5 GPa or more, preferably 0.7 GPa or more, and more preferably 0.8 GPa or more at 200° C. can be.

[0143] The viscosity of the negative photosensitive resin composition according to the present 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.

[0144] A cured product such as a film obtained from the negative photosensitive resin composition of this embodiment has excellent chemical resistance. Specifically, the 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 film thickness reduction rate. Formula: Film reduction rate (%) {(film thickness after immersion - film thickness before immersion) / film thickness before immersion x 100 (%)}

[0145] The film thickness change rate is preferably 40% or less, more preferably 30% or less. This means that even if the cured film is subjected to a process in which it is immersed in dimethyl sulfoxide, the film thickness is hardly reduced. This makes it possible to obtain a cured film that can maintain its function even after being subjected to such a process.

[0146] The negative photosensitive resin composition of this embodiment is suppressed in shrinkage during curing. It is spin-coated on the surface of a silicon wafer so that the film thickness after drying is 10 μm, pre-baked at 120° C. for 3 minutes, and then exposed to a high-pressure mercury lamp at 600 mJ / cm 2and then heat-treating at 170°C for 120 minutes in a nitrogen atmosphere to prepare a film. In this case, the film thickness after the pre-baking is defined as film thickness A, and the film thickness after the heat treatment is defined as film thickness B, and the cure shrinkage calculated from the following formula can be preferably 12% or less, and more preferably 10% or less. Formula: Curing shrinkage rate [%] = {(film thickness A - film thickness B) / film thickness A} x 100

[0147] The negative photosensitive resin composition of this embodiment has high heat resistance, and the weight loss temperature (Td5) of the obtained film measured by simultaneous thermogravimetry and differential thermal analysis can be 200°C or higher, preferably 300°C or higher.

[0148] In a film made of the negative photosensitive resin composition of this embodiment, cure shrinkage is suppressed, and the coefficient of linear thermal expansion (CTE) can be set to 200 ppm / ° C. or less, preferably 100 ppm / ° C. or less.

[0149] A film made of the negative photosensitive resin composition of this embodiment has excellent mechanical strength, and the elastic modulus at 25° C. can be set to 1.0 to 5.0 GPa, preferably 1.5 to 3.0 GPa.

[0150] (Application) The negative photosensitive resin composition of the present embodiment is used to form a resin film for semiconductor devices such as a permanent film and a resist. Among these, from the viewpoint of achieving a good balance between improving the adhesion between the negative photosensitive resin composition and an Al pad after pre-baking 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 a metal, and further improving the chemical resistance of the negative photosensitive resin composition after heat treatment, it is preferable to use the composition in applications using a permanent film.

[0151] In this embodiment, the resin film includes a cured film of a negative photosensitive resin composition. That is, the resin film according to this embodiment is formed by curing a negative photosensitive resin composition.

[0152] The permanent film is a resin film obtained by pre-baking, exposing, and developing a negative photosensitive resin composition, patterning the composition into a desired shape, and then curing the composition by heat treatment. The permanent film can be used as a protective film, an interlayer film, a dam material, etc. for semiconductor devices.

[0153] The resist is composed of a resin film obtained by applying a negative photosensitive resin composition to an object to be masked by the resist by a method such as spin coating, roll coating, flow coating, dip coating, spray coating, doctor coating, or the like, and then removing the solvent from the negative photosensitive resin composition.

[0154] FIG. 1 shows an example of a semiconductor device according to this embodiment. The semiconductor device 100 according to this embodiment can be a semiconductor device including the above-mentioned resin film. Specifically, in 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 including the cured product of this embodiment. Here, the resin film is preferably a permanent film as described above.

[0155] The semiconductor device 100 is, for example, a semiconductor chip. In this case, for example, the semiconductor device 100 is mounted on a wiring board via bumps 52 to obtain a semiconductor package.

[0156] The semiconductor device 100 includes a semiconductor substrate on which semiconductor elements such as transistors are provided, and a multi-layer wiring layer (not shown) provided on the semiconductor substrate. The uppermost layer of the multi-layer wiring layer includes an interlayer insulating film 30 and a top-layer wiring 34 provided on the interlayer insulating film 30. The top-layer wiring 34 is made of, for example, aluminum (Al). A passivation film 32 is provided on the interlayer insulating film 30 and the top-layer wiring 34. An opening is provided in a part of the passivation film 32 to expose the top-layer wiring 34.

[0157] A rewiring layer 40 is provided on the passivation film 32. The rewiring layer 40 has an insulating layer 42 provided on the passivation film 32, a rewiring 46 provided on the insulating layer 42, and an insulating layer 44 provided on the insulating layer 42 and the rewiring 46. An opening connected to the top layer wiring 34 is formed in the insulating layer 42. The rewiring 46 is formed on the insulating layer 42 and in the opening provided in the insulating layer 42, and is connected to the top layer wiring 34. An opening connected to the rewiring 46 is provided in the insulating layer 44.

[0158] Bumps 52 are formed, for example, via a UBM (Under Bump Metallurgy) layer 50, in the openings provided in the insulating layer 44. The semiconductor device 100 is connected, for example, via the bumps 52 to a wiring board or the like. Although the embodiments of the present invention have been described above, these are merely examples of the present invention, and various configurations other than those described above can be adopted as long as they do not impair the effects of the present invention. EXAMPLES

[0159] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these. The following compounds were used in the synthesis of the polymer:

[0160] 4,4-diamino-3,3-diethyl-5,5-dimethyldiphenylmethane (hereinafter also referred to as MED-J), represented by the following formula: [ka]

[0161] 2,2-bis(3-amino-4-hydroxyphenyl)propane (hereinafter referred to as BAPA), represented by the following formula: [ka]

[0162] 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane (hereinafter referred to as BAFA) represented by the following formula [ka]

[0163] 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl (hereinafter also referred to as TFMB) represented by the following formula [ka]

[0164] 4,4'-(hexafluoroisopropylidene)bis[(4-aminophenoxy)benzene] (hereinafter also referred to as HFBAPP), represented by the following formula: [ka]

[0165] A mixture of 1-(4-aminophenyl)-1,3,3-trimethylphenylindan-6-amine and 1-(4-aminophenyl)-1,3,3-trimethylphenylindan-5-amine (hereinafter referred to as TMDA) represented by the following formula: [ka]

[0166] 9,9-bis(3-methyl-4-aminophenyl)fluorene (hereinafter referred to as BTFL) represented by the following formula [ka]

[0167] 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: [ka]

[0168] p-phenylenebis(trimellitate anhydride) (hereinafter also referred to as TMHQ) represented by the following formula [ka]

[0169] [Example 1] First, 9.67 g (34.2 mmol) of MED-J, 2.95 g (11.4 mmol) of BAPA, and 33.62 g (54.3 mmol) of TMPBP-TME were added to a suitable sized reaction vessel equipped with a stirrer and condenser, followed by the addition of 138.71 g of GBL. After nitrogen was passed through for 10 minutes, the temperature was raised to 60°C while stirring, and the reaction was carried out for 1.5 hours. Thereafter, the reaction was further carried out at 180°C for 3 hours to polymerize the bisaminophenol and the acid anhydride, producing a polymerized solution. The polymer was subjected to GPC measurement, and the weight average molecular weight Mw was 21,500 and the polydispersity (weight average molecular weight Mw / number average molecular weight Mn) was 2.02. Next, 6.44 g (45.6 mmol) of 2-isocyanatoethyl acrylate (hereinafter also referred to as AOI, manufactured by Showa Denko K.K.) and 43.02 g of γ-butyrolactone (GBL) were added to the total amount of the obtained polyimide solution (22.8 mmol in terms of hydroxyl groups), and the temperature was then raised to 120° C. with stirring, and the reaction was carried out for 6 hours. The reaction solution was diluted with tetrahydrofuran to prepare a dilution, and then the dilution was added dropwise to methanol to precipitate a white solid. The resulting white solid was collected and vacuum-dried at 40° C. to obtain 43.73 g of a polymer. The polymer was subjected to GPC measurement, and the weight average molecular weight Mw was 22,800 and the polydispersity (weight average molecular weight Mw / number average molecular weight Mn) was 2.15. Also, 1When H-NMR measurement was performed, a peak was confirmed in the aromatic region (6.8 ppm to 8.8 ppm) with an area ratio corresponding to the number of protons. In addition, based on the area ratio of the aromatic region (6.8 ppm to 8.8 ppm) and the alkene region (5.8 ppm to 6.3 ppm), the introduction rate of the crosslinking group was 100%. The polymer into which the crosslinking group was introduced contained a repeating unit represented by the following formula in part. [ka]

[0170] [Example 2] First, 12.89 g (45.7 mmol) of MED-J and 33.62 g (54.3 mmol) of TMPBP-TME were placed in a suitable sized reaction vessel equipped with a stirrer and a condenser, and then 125.58 g of GBL was added to the reaction vessel. After nitrogen was passed through for 10 minutes, the temperature was raised to 60°C while stirring, and the reaction was carried out for 1.5 hours. Thereafter, the reaction was further carried out at 180°C for 3 hours to polymerize the bisaminophenol and the acid anhydride, producing a polymerized solution. The polymer was subjected to GPC measurement, and the weight average molecular weight Mw was 23,600 and the polydispersity (weight average molecular weight Mw / number average molecular weight Mn) was 2.05. Next, 4.91 g (34.8 mmol) of 2-isocyanatoethyl acrylate (hereinafter also referred to as AOI, manufactured by Showa Denko K.K.) and 44.06 g of γ-butyrolactone (GBL) were added to the total amount of the obtained polyimide solution (17.4 mmol calculated based on no terminal acid), and the temperature was then raised to 120° C. with stirring, and the reaction was carried out for 6 hours. The reaction solution was diluted with tetrahydrofuran to prepare a diluted solution, and then the diluted solution was added dropwise to methanol to precipitate a white solid. The resulting white solid was collected and vacuum-dried at 40° C. to obtain 41.73 g of a polymer. The polymer was subjected to GPC measurement, and the weight average molecular weight Mw was 23,100 and the polydispersity (weight average molecular weight Mw / number average molecular weight Mn) was 2.09. Also,1 When H-NMR measurement was performed, a peak was confirmed in the aromatic region (6.9 ppm to 8.9 ppm) with an area ratio corresponding to the number of protons. In addition, based on calculations from the area ratio of the aromatic region (6.9 ppm to 8.9 ppm) and the alkene region (5.8 ppm to 6.5 ppm) and the degree of polymerization, the introduction rate of the crosslinking group to the terminal was 100%. The obtained polymer contained a repeating unit represented by the following formula in part, and had a crosslinking group introduced at the end. [ka]

[0171] [Examples 3 to 6, Comparative Examples 1 to 5] For Examples 3 to 6 and Comparative Examples 1 to 5, synthesis was carried out in the same manner as in Example 1, except for the conditions shown in Table 1. The obtained Mw, Mw / Mn, and crosslinking group introduction rate are shown in the table. In Comparative Examples 1 and 2, gelation occurred during the polymerization reaction, making it difficult to continue the reaction, and therefore the solubility of the solvent in GBL was rated as x.

[0172] [Average value of the positive charges (δ+) of the two carbonyl carbons of the imide ring] The average value of the positive charges (δ+) of the two carbonyl carbons of the imide ring of the negative photosensitive polymer obtained in Example 1 was calculated as follows. The negative photosensitive polymer of Example 1 contains a structural unit (A) represented by the following chemical formula (A) and a structural unit (B) represented by the following chemical formula (B). [ka] In this case, the compound (A') represented by the following chemical formula (A') was measured by the charge equilibration method using the software HSPiP (ver5.3), and the average value (1) was obtained by averaging the δ+ of the two carbonyl carbons (*1, *2) of the imide ring contained in the compound (A'). The compound (B') represented by the following chemical formula (B') was measured in the same manner, and the average value (2) was obtained by averaging the δ+ of the two carbonyl carbons (*1, *2) of the imide ring contained in the compound. Then, when the sum of the moles of the structural unit (A) 34.2 mmol and the moles of the structural unit (B) 11.4 mmol was taken as 100, the δ+ was calculated by the following formula. Formula: [average value of δ+(1) × mole fraction(1) + average value of δ+(2) × mole fraction(2)] / 100 = [0.087 × 75 + 0.098 × 25] / 100 = 0.090 The same calculations were made for other examples and comparative examples. [ka]

[0173] [Solubility in organic solvents] The solubility of the negative-type photosensitive polymers obtained in the Examples and Comparative Examples in γ-butyrolactone (GBL) or OK73 (a mixed solution of propylene glycol monomethyl ether (PGME) and propylene glycol monomethyl ether acetate (PGMEA) (mixture ratio 7:3), manufactured by Tokyo Applied Chemical Industry Co., Ltd.) was evaluated according to the following criteria. The results are shown in Table 1. (Solubility Evaluation Criteria) ○: 5% or more of polymer is dissolved △: 1 to 5% by mass of polymer dissolved ×: Polymer dissolution is less than 1% by mass

[0174] [Hydrolysis resistance] The reduction rate of the weight average molecular weight of the negative photosensitive polymers obtained in the Examples and Comparative Examples was measured under the following conditions. The results are shown in Table 1.

[0175] (Conditions (no triethylamine added)) The following formula was used to calculate the viscosity when 100 parts by mass of a negative photosensitive polymer was added with 400 parts by mass of γ-butyrolactone, 200 parts by mass of 4-methyltetrahydropyran, and 50 parts by mass of water and stirred at 100° C. for 6 hours. Formula: [(Weight average molecular weight before test - Weight average molecular weight after test) / Weight average molecular weight before test] x 100

[0176] (Conditions (triethylamine added)) The calculation was performed using the following formula when 100 parts by mass of negative photosensitive polymer was added with 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, and stirred at 100° C. for 6 hours. Formula: [(Weight average molecular weight before test - Weight average molecular weight after test) / Weight average molecular weight before test] x 100

[0177] [Elongation rate] A composition containing the polymer solution (100 parts by mass of polymer) obtained in the comparative example, 5 parts by mass of thermal radical generator Perkadox BC, 2 parts by mass of adhesion aid KBM-503P, and 0.1 parts by mass of surfactant FC4432 was spin-coated onto the surface of a silicon wafer, prebaked at 110°C for 3 minutes, and then heat-treated at 170°C for 240 minutes under nitrogen to prepare a film. Details of each component are described below. A tensile test (stretching speed: 5 mm / min) was carried out on a test piece (6.5 mm x 60 mm x 10 μm thick) cut out from the obtained film in an atmosphere of 23°C. The tensile test was carried out using a tensile tester (Tensilon RTC-1210A) manufactured by Orientec Co., Ltd. Ten test pieces were measured, and the tensile elongation was calculated from the break distance and the initial distance, and the maximum elongation was obtained. Furthermore, the test pieces cut out from the film were subjected to HAST (unsaturated pressurized steam test) for 96 hours under conditions of a temperature of 130°C and a relative humidity of 85%RH, and the maximum elongation was then determined in the same manner as above.

[0178] [Table 2]

[0179] As shown in Table 1, the negative-type photosensitive polymers of the present invention obtained in the Examples in which the average value of the positive charges (δ+) of the two carbonyl carbons of the imide ring is 0.099 or less have excellent solubility in organic solvents, and since hydrolysis is suppressed, it is presumed that the decrease in elongation is small and the decrease in mechanical strength is suppressed.

[0180] The following compounds were used in the preparation of the negative photosensitive resin composition. (Crosslinking agent) Acrylate compound 1: Dipentaerythritol hexaacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., NK Ester A-DPH)

[0181] (Polymerization initiator) Photoradical generator: 2-(dimethylamino)-1-(4-(4-morpholino)phenyl)-2-(phenylmethyl)-1-butanone (Irgacure Oxe01, BASF Japan) Thermal radical generator: Dicumyl peroxide (Perkadox BC, peroxide, manufactured by Kayaku Akzo Co., Ltd.)

[0182] (Adhesion aid) Adhesion aid 1: 3-methacryloxypropyltrimethoxysilane (KBM-503P, Shin-Etsu Chemical Co., Ltd.)

[0183] (Surfactant) Surfactant 1: Surfactant with a fluorocarbon chain (FC-4432, manufactured by Sumitomo 3M)

[0184] (solvent) Solvent 1: γ-Butyrolactone (GBL)

[0185] [Example 7] (Preparation of negative type photosensitive resin composition) The polymer of Example 3 (100 parts by mass of polymer) and the components shown in Table 2, which had been dissolved in advance to give a 22 wt % GBL solution, were mixed together to prepare a photosensitive resin composition. The obtained negative photosensitive resin composition was spin-coated onto the surface of a silicon wafer so that the film thickness after drying was 10 μm, and the wafer was pre-baked at 120° C. for 3 minutes, and then exposed to a high-pressure mercury lamp at 600 mJ / cm 2 2 After that, the film was subjected to a heat treatment at 170° C. for 120 minutes in a nitrogen atmosphere to prepare a film. The glass transition temperature (Tg) and elongation of the obtained film were measured by the following methods, and the patterning properties were evaluated. The results are shown in Table 2.

[0186] [Glass transition temperature (Tg)] A test piece of 8 mm × 40 mm was cut out from the film obtained in Example 7, and dynamic viscoelasticity measurement was performed on the test piece using a dynamic viscoelasticity measurement device (DMA device, manufactured by TA Instruments, Q800) at a heating rate of 5°C / min and a frequency of 1 Hz, and the temperature at which the loss tangent tanδ was maximum was measured as the glass transition temperature.

[0187] [Elongation rate] A tensile test (stretching speed: 5 mm / min) was carried out in an atmosphere of 23°C on a test piece (6.5 mm x 60 mm x 10 μm thick) cut out from the film obtained in Example 7. The tensile test was carried out using a tensile tester (Tensilon RTC-1210A) manufactured by Orientec Co., Ltd. The strength was determined by measuring the stress at the breaking point on five test pieces and averaging the stress at the breaking point. The tensile elongation was calculated from the breaking distance and the initial distance, and the average and maximum elongation values ​​were obtained. Furthermore, the test pieces cut out from the film obtained in Example 7 were subjected to HAST (unsaturated pressurized steam test) for 96 hours under conditions of a temperature of 130°C and a relative humidity of 85%RH, and then the average and maximum elongations were determined in the same manner as described above.

[0188] [Evaluation of patterning characteristics] It was confirmed as follows that the photosensitive resin composition of Example 7 could be sufficiently patterned by exposure and development. The photosensitive resin composition of Example 7 was applied onto an 8-inch silicon wafer using a spin coater. After application, the wafer was prebaked at 110° C. for 3 minutes on a hot plate in the atmosphere to obtain a coating film having a thickness of about 5.0 μm. This coating was irradiated with i-line through a mask with a 20 μm wide via pattern by using an i-line stepper (Nikon Corporation, NSR-4425i). After the exposure, spray development was carried out for 40 seconds using cyclopentanone as a developer, and further spray development was carried out for 10 seconds using PGMEA as a developer to dissolve and remove the unexposed areas, thereby obtaining a via pattern. The cross section of the obtained via pattern was observed using a benchtop SEM. The width at the midpoint between the bottom surface and the opening of the via pattern was taken as the via width, and was evaluated according to the following criteria. Good patterning: 20μm via pattern opened Poor patterning: 20μm via pattern does not open The coating film obtained from the photosensitive resin composition of Example 7 had good patterning properties.

[0189] [Table 3]

[0190] As shown in Table 2, a film obtained from a negative-type photosensitive resin composition containing a negative-type photosensitive polymer in which the average value of the positive charges (δ+) of the two carbonyl carbons of the imide ring is 0.099 or less was found to have excellent elongation and, since the film contains a negative-type photosensitive polymer with excellent hydrolysis resistance, it was found to have excellent mechanical strength even after the HAST test. In addition, the patterning property was also good, and it was confirmed that the film is suitable for use as a negative-type photosensitive resin composition.

[0191] This application claims priority based on Japanese Patent Application No. 2021-105682, filed on June 25, 2021, and Japanese Patent Application No. 2022-019323, filed on February 10, 2022, the disclosures of which are incorporated herein in their entirety. [Explanation of symbols]

[0192] 100 Semiconductor device 30 Interlayer insulating film 32 Passivation film 34 Top layer wiring 40 Redistribution layer 42 Insulating layer 44 Insulating layer 46 Rewiring 50 UBM layers 52 Bump

Claims

1. A solvent-soluble negative-type photosensitive polymer comprising a structural unit containing an imide ring and a group having a terminal double bond, A negative-type photosensitive polymer in which the average value of the positive charges (δ+) of the two carbonyl carbons of the imide ring is 0.099 or less as calculated by a charge equilibration method (however, the negative-type photosensitive polymer excludes at least one resin selected from the group consisting of polyimide, polybenzoxazole, polyimide precursor, and polybenzoxazole precursor, each of which contains a structure represented by the following formula (1-1), and at least one resin selected from the group consisting of polyimide and polyimide precursor having a polyalkyleneoxy group and a polymerizable group, wherein the polymerizable group is a group containing an ethylenically unsaturated group, a cyclic ether group, or a methylol group): 【Chemistry 1】 (In formula (1-1), R 1 represents a hydrogen atom or a substituent, and when R 1 is a hydrogen atom or a substituent not containing the polymerizable group, the resin contains a structure having the polymerizable group as a structure other than the structure represented by formula (1-1)).

2. 2. The negative photosensitive polymer according to claim 1, which does not contain a fluorine atom in its molecular structure.

3. 3. The negative photosensitive polymer according to claim 1, wherein the structural unit is represented by the following general formula (1): 【Chemistry 2】 (In the general formula (1), X represents a divalent organic group containing an aromatic group, A represents a ring structure containing two carbon atoms of the imide ring, Q represents a divalent organic group.

4. 4. The negative type photosensitive polymer according to claim 3, wherein an aromatic group contained in the divalent organic group of X in the general formula (1) is bonded to a nitrogen atom in the general formula (1) and has electron-donating groups at two ortho positions relative to the carbon atom bonded to the nitrogen atom.

5. 4. The negative type photosensitive polymer according to claim 3, wherein X in the general formula (1) is a divalent group represented by the following general formula (1a) or the following general formula (1b): 【Chemistry 3】 (In general formula (1a), R １ ~R ４ 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; R １ and R ２ are different groups, and R ３ and R ４ are different groups. X １ is a single bond, -SO ２ It represents --, --C(.dbd.O)--, a straight-chain or branched alkylene group having 1 to 5 carbon atoms, or a fluorenylene group. * represents a bond. In general formula (1b), R ａ , R ｂ 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 R exists in multiple places ｂ may be the same or different. * indicates a bond.)

6. 4. The negative photosensitive polymer according to claim 3, wherein X in the general formula (1) contains a divalent group represented by the following general formula (1c) which has a group having a terminal double bond: 【Chemistry 4】 In general formula (1c), 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. 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 ２ is a single bond, -SO ２ -, -C(=O)-, a straight or branched alkylene group having 1 to 5 carbon atoms. * indicates a bond.

7. 3. The negative photosensitive polymer according to claim 1, which has a group having a terminal double bond at at least one of both ends.

8. 4. The negative photosensitive polymer according to claim 3, wherein A in the general formula (1) is an aromatic ring.

9. 4. The negative photosensitive polymer according to claim 3, wherein Q in the general formula (1) is a divalent group containing an imide ring.

10. 6. The negative type photosensitive polymer according to claim 5, wherein the structural unit represented by the general formula (1) includes a structural unit represented by the following general formula (1-1): 【Chemistry 5】 (In general formula (1-1), X is a divalent group represented by general formula (1a) or general formula (1b), and Y is a divalent organic group.)

11. 11. The negative type photosensitive polymer according to claim 10, wherein X in the general formula (1-1) contains a divalent group represented by the general formula (1c).

12. The negative type photosensitive polymer according to claim 10, wherein Y in the general formula (1-1) is a divalent organic group selected from the following general formulae (a1-1), (a1-2), (a1-3), and (a1-4): 【Chemistry 6】 (In 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, ７ R exists in multiple places ８ R may be the same or different. 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 ９ may be the same or different. * indicates a bond. In 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, １０ R exists in multiple places １１ may be the same or different. * indicates a bond. In general formula (a1-3), Z １ represents an alkylene group having 1 to 5 carbon atoms or a divalent aromatic group. * represents a bond. In general formula (a1-4), Z ２ indicates a divalent aromatic group. * indicates a bond.)

13. 3. The negative photosensitive polymer according to claim 1, which is soluble in a solvent selected from the group consisting of N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, γ-butyrolactone (GBL), and cyclopentanone in an amount of 5% by mass or more.

14. 3. The negative photosensitive polymer according to claim 1, which is soluble in γ-butyrolactone (GBL) in an amount of 5% by mass or more.

15. 3. The negative photosensitive polymer according to claim 1, wherein the reduction rate of the weight average molecular weight measured under the following conditions is 15% or less. (conditions) The viscosity is calculated according to the following formula 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. Formula: [(weight average molecular weight before test−weight average molecular weight after test) / weight average molecular weight before test]×100

16. A polymer solution comprising the negative photosensitive polymer according to claim 1 or 2.

17. (A) the negative type photosensitive polymer according to claim 1 or 2; (B) a crosslinking agent containing a polyfunctional (meth)acrylate; (C) a photopolymerization initiator; A negative type photosensitive resin composition comprising:

18. A cured film comprising a cured product of the negative photosensitive resin composition according to claim 17.

19. A semiconductor device comprising a resin film containing a cured product of the negative photosensitive resin composition according to claim 17.

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