Polyimide resins, varnishes, photosensitive resin compositions, cured products, and semiconductor devices

Abstract

This invention provides a polyimide resin with an improved balance between solvent solubility and elastic modulus. [Solution] A polyimide resin comprising a constituent unit represented by the following general formula (1). TIFF2026069456000058.tif44153 (In general formula (1), X represents a divalent organic group (constituent unit (X)), Y represents a tetravalent organic group (constituent unit (Y), and the constituent unit (X) includes the constituent unit (X-1) represented by the following general formula (x1).) TIFF2026069456000059.tif38153

Description

[Technical Field]

[0001] The present invention relates to polyimide resins, varnishes, photosensitive resin compositions, cured products, and semiconductor devices. [Background technology]

[0002] Polyimide resins are widely used as thin films for electronic materials such as semiconductor protective materials, insulating materials, and color filters due to their high mechanical strength, heat resistance, insulation, and solvent resistance.

[0003] Patent Document 1 describes a polyimide resin comprising a constituent unit A derived from a tetracarboxylic dianhydride and a constituent unit B derived from a diamine compound, with the objective of providing a polyimide resin with a high glass transition temperature. The polyimide resin is described as having a constituent unit A comprising at least one of constituent units (A-1), (A-2), and (A-3) derived from a compound represented by a predetermined formula, and a constituent unit B comprising a constituent unit (B-1) derived from a compound represented by a predetermined formula, wherein the ratio of constituent unit (B-1) in constituent unit B is 60 mol% or more, and the glass transition temperature exceeds 410°C. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] International Publication No. 2017 / 191822 [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] This invention provides a polyimide resin with an improved balance between solvent solubility and elastic modulus. [Means for solving the problem]

[0006] The inventors of the present invention have found that a polyimide resin containing a predetermined structural unit can improve the balance between solvent solubility and elastic modulus, and have completed the present invention.

[0007] That is, according to the present invention, there are provided a polyimide resin, a varnish, a photosensitive resin composition, a cured product, and a semiconductor device as shown below.

[0008] [1] A polyimide resin containing a structural unit represented by the following general formula (1). [Chemical formula] (In general formula (1), X represents a structural unit (X) which is a divalent organic group, Y represents a structural unit (Y) which is a tetravalent organic group, The structural unit (X) includes a structural unit (X-1) represented by the following general formula (x1).) [Chemical formula] (In general formula (x1), R 1 each independently represents an alkyl group having 1 to 4 carbon atoms, a and b each independently represent an integer of 0 to 4, * represents a bond.) [2] The polyimide resin according to [1], wherein the structural unit (Y) includes a structural unit (Y-1) represented by the following general formula (y1). [Chemical formula] (In general formula (y1), R 5 each independently represents an alkyl group having 1 to 4 carbon atoms, Z 1 represents a single bond or a divalent organic group, g and h each independently represent an integer of 0 to 4, * represents a bond.) [3] The polyimide resin according to [2], wherein the ratio of the structural unit (Y-1) in the structural unit (Y) is 10 mol% or more. [4] The aforementioned constituent unit (Y) includes a constituent unit (Y-2) represented by the following general formula (y2), and is a polyimide resin according to any one of [1] to [3]. [ka] (In general formula (y2), Z 2 This represents a single bond, -C(=O)-, or -SO2-. * represents a bond. [5] The polyimide resin according to any one of [1] to [4], wherein the aforementioned constituent unit (X) further comprises a constituent unit (X-2) represented by the following general formula (x2). [ka] (In general formula (x2), R 2 Each of these independently represents an alkyl group having 1 to 4 carbon atoms. c and d each independently represent integers from 0 to 4. * represents a bond. [6] The polyimide resin according to any one of [1] to [5], wherein the aforementioned constituent unit (X) further comprises a constituent unit (X-3) represented by the following general formula (x3). [ka] (In the general formula (x3), * represents a bond.) [7] The polyimide resin according to any one of [1] to [6], wherein the aforementioned constituent unit (X) further comprises a constituent unit (X-4) represented by the following general formula (x4). [ka] (In general formula (x4), R 3 Each of these independently represents an alkyl group having 1 to 4 carbon atoms. e and f each independently represent integers between 0 and 3. * represents a bond. [8] The polyimide resin according to any one of [1] to [7], wherein the aforementioned constituent unit (X) further comprises a constituent unit (X-5) represented by the following general formula (x5). [ka] (In general formula (x5), R 4 Each of these independently represents either a methyl group or a trifluoromethyl group. * represents a bond. [9] The polyimide resin according to any one of [1] to [8], wherein the weight-average molecular weight of the polyimide resin is 5,000 or more and 150,000 or less.

[10] A polyimide resin as described in any one of [1] to [9], wherein the storage modulus at 30°C is greater than 3.3 GPa, as measured by dynamic viscoelasticity measurement (DMA) in accordance with JIS K 7244-4:1999.

[11] A polyimide resin as described in any one of [1] to

[10] , wherein the glass transition temperature, as measured by dynamic viscoelasticity measurement (DMA) in accordance with JIS K 7244-4:1999, is 300°C or higher.

[12] A polyimide resin as described in any one of [1] to

[11] , wherein the mean coefficient of linear thermal expansion (CTE) in the range of 50°C to 100°C, as measured by thermomechanical analysis (TMA) in accordance with JIS K 7197:2012, is less than 49 ppm / °C.

[13] A polyimide resin according to any one of [1] to

[12] , wherein the average value of the elongation at break at 23°C obtained by the following method is 5% or more. (method) A solution is prepared by dissolving 4 g of polyimide resin in 16 g of γ-butyrolactone. The solution is spin-coated onto an 8-inch silicon wafer, and then heated at 110°C for 3 minutes to dry the solution. The spin-coating is performed so that the film thickness after drying is 10 μm. Next, the wafer is heated at 170°C for 3 hours under a nitrogen atmosphere to form a cured film. The silicon wafer with the cured film is cut to a width of 7 mm using a dicing saw. The cut silicon wafer is immersed in a 2 mass% hydrofluoric acid aqueous solution to peel off the cured film from the silicon wafer. The peeled cured film is dried at 80°C for 90 minutes to obtain a cured film. A test piece (50 mm × 7 mm × 10 μm thick) is cut from the obtained cured film. In accordance with JIS K 7197:2012, the elongation at break from the initial position to the fracture point of the test specimen is measured using a thermomechanical analyzer under air atmosphere, tensile mode, chuck distance of 20 mm, tensile speed of 5 mm / min, and 23°C. Measurements are performed on 10 test specimens, and the average value of the elongation at break is calculated.

[14] A varnish comprising a polyimide resin and a solvent as described in any one of [1] to

[13] .

[15] A polyimide resin described in any one of [1] to

[13] , Polymerization initiator and A photosensitive resin composition containing [the specified element].

[16] The photosensitive resin composition according to

[15] , further comprising a polyfunctional (meth)acrylate.

[17] The photosensitive resin composition according to

[16] , wherein the polyfunctional (meth)acrylate comprises a (meth)acrylate with five or more functionalities.

[18] The photosensitive resin composition according to

[16] or

[17] , wherein the polyfunctional (meth)acrylate comprises a (meth)acrylate with two or more functions and four or fewer functions.

[19] The photosensitive resin composition according to any one of

[16] to

[18] , wherein the content of the polyfunctional (meth)acrylate per 100 parts by mass of the polyimide resin is 20 parts by mass or more and 150 parts by mass or less.

[20] A photosensitive resin composition according to any one of

[15] to

[19] , further comprising an epoxy compound. [twenty one] The photosensitive resin composition according to

[20] , wherein the epoxy compound comprises an epoxy compound having a (meth)acryloyl group. [twenty two] A photosensitive resin composition according to any one of

[15] to

[21] , further comprising a silane coupling agent. [twenty three] The photosensitive resin composition according to

[22] , comprising a silane coupling agent having a cyclic anhydride structure. [twenty four] A photosensitive resin composition used in semiconductor devices, according to any one of

[15] to

[23] . [twenty five] A cured product of any one of the photosensitive resin compositions described in

[15] to

[24] .

[26] A semiconductor device comprising the cured product described in

[25] .

[27] Interlayer insulating film and A resin film containing the cured product described in

[25] is provided on the interlayer insulating film, The rewiring embedded in the aforementioned resin film, The semiconductor device described in

[26] , comprising: [Effects of the Invention]

[0009] According to the present invention, a polyimide resin with an improved balance between solvent solubility and elastic modulus can be provided. [Brief explanation of the drawing]

[0010] [Figure 1] This is a schematic cross-sectional view illustrating an example of the structure of the semiconductor device according to this embodiment. [Modes for carrying out the invention]

[0011] Embodiments of the present invention will be described below. In this specification, "A to B" indicating a numerical range means A or greater and B or less unless otherwise specified. In this specification, the notation "(meth)acrylate" represents a concept that encompasses both acrylate and methacrylate. The same applies to similar notations such as "(meth)acrylic". Also, the figures are schematic diagrams and do not correspond to actual dimensional ratios.

[0012] (Polyimide resin) The polyimide resin of this embodiment includes a constituent unit represented by the following general formula (1).

[0013] [ka]

[0014] In general formula (1), X represents a divalent organic group (X) and Y represents a tetravalent organic group (Y).

[0015] In this embodiment, the constituent unit (X) includes the constituent unit (X-1) represented by the following general formula (x1).

[0016] [ka]

[0017] In general formula (x1), R 1 Each of these independently represents an alkyl group having 1 to 4 carbon atoms. a and b each independently represent integers from 0 to 4. * represents a bond.

[0018] In this embodiment, constituent unit (X) includes constituent unit (X-1). That is, since the polyimide resin of this embodiment has a cardo structure, it is thought that its solvent solubility can be improved. Furthermore, it is thought that the inclusion of constituent unit (X-1) in constituent unit (X) improves the balance between the solvent solubility and elastic modulus of the polyimide resin.

[0019] Furthermore, since the polyimide resin of this embodiment has a cardo structure, it is considered that the heat resistance can be improved. That is, according to the polyimide resin of this embodiment, it is considered that the balance between solvent solubility and heat resistance can be improved.

[0020] In the general formula (x1), R 1 each independently represents an alkyl group having 1 to 4 carbon atoms. R 1 may contain at least one group selected from the group consisting of a methyl group, an ethyl group, an isopropyl group, an n-propyl group, and a tert-butyl group, may contain at least one group selected from the group consisting of a methyl group and an ethyl group, and may contain a methyl group.

[0021] In the general formula (x1), a and b each independently represent an integer of 0 to 4. a and b may each independently be an integer of 0 to 2, may be 0 or 1, and may be 1.

[0022] The structural unit (X-1) may contain at least one selected from the group consisting of, for example, a structural unit represented by the following formula (x11) and a structural unit represented by the following formula (x12), and may contain a structural unit represented by the following formula (x11).

[0023] [Chemical formula]

[0024] [Chemical formula]

[0025] In the above formula, * represents a bond.

[0026] The ratio of constituent unit (X-1) to constituent unit (X) is preferably 10 mol% or more, more preferably 20 mol% or more, even more preferably 30 mol% or more, and even more preferably 35 mol% or more. By setting the ratio of constituent unit (X-1) to constituent unit (X) to the above lower limit or higher, the balance between the solvent solubility and elastic modulus of the polyimide resin can be further improved. Furthermore, the balance between the solvent solubility and heat resistance of the polyimide resin can be further improved. The upper limit of the ratio of constituent unit (X-1) to constituent unit (X) is not particularly limited, but for example, it may be 100 mol% or less, 95 mol% or less, or 90 mol% or less.

[0027] The ratio of the constituent unit represented by formula (x11) in constituent unit (X) is preferably 10 mol% or more, more preferably 20 mol% or more, even more preferably 30 mol% or more, and even more preferably 35 mol% or more. By setting the ratio of the constituent unit represented by formula (x11) in constituent unit (X) to be above the lower limit, the balance between the solvent solubility and elastic modulus of the polyimide resin can be further improved. Furthermore, the balance between solvent solubility and heat resistance can be further improved. The upper limit of the ratio of the constituent unit represented by formula (x11) in constituent unit (X) is not particularly limited, but for example, it may be 100 mol% or less, 95 mol% or less, or 90 mol% or less.

[0028] The constituent units contained in the polyimide resin of this embodiment will be described in more detail below.

[0029] (Constituent unit (X)) The constituent unit (X) preferably further comprises a constituent unit (X-2) represented by the following general formula (x2).

[0030] [ka]

[0031] In general formula (x2), R 2 Each of these independently represents an alkyl group having 1 to 4 carbon atoms. c and d each independently represent integers from 0 to 4. * represents a bond.

[0032] The constituent unit (X-2) is considered to have a flexible structure because it contains two ether groups. Therefore, it is thought that the moldability of the polyimide resin can be improved by including the constituent unit (X-2) in the constituent unit (X).

[0033] In general formula (x2), R 2 Each of these independently represents an alkyl group having 1 to 4 carbon atoms. 2 It may contain at least one group selected from the group consisting of methyl group, ethyl group, isopropyl group, n-propyl group, and tert-butyl group, and may contain at least one group selected from the group consisting of methyl group and ethyl group, and may contain a methyl group.

[0034] In the general formula (x²), c and d each independently represent integers from 0 to 4. C and d can each independently be 0 or 1, or they can be 0.

[0035] The constituent unit (X-2) may include, for example, the constituent unit represented by the following formula (x21).

[0036] [ka]

[0037] In equation (x21), * represents a bond.

[0038] The ratio of constituent unit (X-2) to constituent unit (X) is preferably greater than 0 mol% and 90 mol% or less, more preferably 5 mol% to 80 mol%, even more preferably 10 mol% to 70 mol%, and even more preferably 20 mol% to 60 mol%. By setting the ratio of constituent unit (X-2) to constituent unit (X) within the above range, the balance between the solvent solubility and elastic modulus of the polyimide resin can be further improved.

[0039] The ratio of constituent unit (X-2) to constituent unit (X-1) in constituent unit (X) is preferably greater than 0 mol% and 200 mol% or less, more preferably 10 mol% to 150 mol%, even more preferably 20 mol% to 120 mol%, and even more preferably 30 mol% to 100 mol%. By setting the ratio of constituent unit (X-2) to constituent unit (X-1) within the above range, the balance between the solvent solubility and elastic modulus of the polyimide resin can be further improved.

[0040] When the constituent unit (X-1) includes the constituent unit represented by formula (x11), the ratio of constituent unit (X-2) to the constituent unit represented by formula (x11) in constituent unit (X) is preferably greater than 0 mol% and 200 mol% or less, more preferably 10 mol% or more and 150 mol% or less, even more preferably 20 mol% or more and 120 mol% or less, and even more preferably 30 mol% or more and 100 mol% or less. By setting the ratio of constituent unit (X-2) to the constituent unit represented by formula (x11) within the above range, the balance between the solvent solubility and elastic modulus of the polyimide resin can be further improved.

[0041] The constituent unit (X) may further include the constituent unit (X-3) represented by the following general formula (x3).

[0042] [ka]

[0043] In the general formula (x3), * represents a bond.

[0044] The constituent unit (X-3) may include, for example, the constituent unit represented by the following formula (x31).

[0045] [ka]

[0046] In equation (x31), * represents a bond.

[0047] The constituent unit (X) may further include the constituent unit (X-4) represented by the following general formula (x4).

[0048] [ka]

[0049] In general formula (x4), R 3 Each of these independently represents an alkyl group having 1 to 4 carbon atoms. e and f each independently represent integers between 0 and 3. * represents a bond.

[0050] In general formula (x4), R 3 Each of these independently represents an alkyl group having 1 to 4 carbon atoms. 3 It may contain at least one group selected from the group consisting of methyl group, ethyl group, isopropyl group, n-propyl group, and tert-butyl group, and may contain at least one group selected from the group consisting of methyl group and ethyl group, and may contain a methyl group.

[0051] In the general formula (x4), e and f each independently represent integers between 0 and 3. E and f may each independently be 0 or 1, or 1.

[0052] The constituent unit (X-4) may include, for example, the constituent unit represented by the following formula (x41).

[0053] [ka]

[0054] In equation (x41), * represents a bond.

[0055] The constituent unit (X) may further include the constituent unit (X-5) represented by the following general formula (x5).

[0056] [ka]

[0057] In general formula (x5), R 4 Each of these independently represents either a methyl group or a trifluoromethyl group. * represents a bond.

[0058] In general formula (x5), R 4 Each of these independently represents either a methyl group or a trifluoromethyl group. 4 It may contain a methyl group.

[0059] The constituent unit (X-5) may include, for example, the constituent unit represented by the following formula (x51).

[0060] [ka]

[0061] In equation (x51), * represents a bond.

[0062] (Constituent unit (Y)) The constituent unit (Y) preferably includes a constituent unit (Y-1) represented by the following general formula (y1).

[0063] [ka]

[0064] In general formula (y1), R 5 Each of these independently represents an alkyl group having 1 to 4 carbon atoms. Z 1 This represents a single bond or a divalent organic group. g and h each independently represent integers from 0 to 4. * represents a bond.

[0065] By including constituent unit (Y-1) within constituent unit (Y), the balance between the solvent solubility and elastic modulus of the polyimide resin can be further improved. Furthermore, the mean coefficient of linear thermal expansion (CTE) of the polyimide resin can be reduced.

[0066] In general formula (y1), R 5 Each of these independently represents an alkyl group having 1 to 4 carbon atoms. 5 Preferably, it comprises at least one group selected from the group consisting of methyl, ethyl, isopropyl, n-propyl, and tert-butyl groups, more preferably at least one group selected from the group consisting of methyl, isopropyl, and tert-butyl groups, and even more preferably a methyl group. This can further improve the solvent solubility of the polyimide resin. It can also reduce the mean coefficient of linear thermal expansion (CTE) of the polyimide resin.

[0067] In the general formula (y1), g and h each independently represent integers from 0 to 4. g and h may also independently be integers from 0 to 3, or they may be 3.

[0068] In general formula (y1), Z 1 Z represents a single bond or a divalent organic group. 1 Preferably, the group is a single bond, a cyclohexane-1,1-diyl group, a phenylene group, or a biphenyl-4,4'-diyl group, more preferably a single bond or a cyclohexane-1,1-diyl group, and even more preferably a single bond. This can further improve the solvent solubility of the polyimide resin. It can also reduce the mean coefficient of linear thermal expansion (CTE) of the polyimide resin.

[0069] The constituent unit (Y-1) preferably includes a constituent unit represented by the following formula (y11). This allows for a better balance between the solvent solubility and elastic modulus of the polyimide resin. It also allows for a reduction in the mean coefficient of linear expansion (CTE) of the polyimide resin.

[0070] [ka]

[0071] In equation (y11), * represents a bond.

[0072] The ratio of constituent unit (Y-1) to constituent unit (Y) is preferably 10 mol% or more, more preferably 20 mol% or more, even more preferably 30 mol% or more, even more preferably 40 mol% or more, and even more preferably 50 mol% or more. By setting the ratio of constituent unit (Y-1) to constituent unit (Y) to the above lower limit or higher, the balance between the solvent solubility and elastic modulus of the polyimide resin can be further improved. The upper limit of the ratio of constituent unit (Y-1) to constituent unit (Y) is not particularly limited, but for example, it may be 100 mol% or less, 95 mol% or less, or 90 mol% or less.

[0073] The ratio of the constituent units represented by formula (y11) in constituent unit (Y) is preferably 10 mol% or more, more preferably 20 mol% or more, even more preferably 30 mol% or more, even more preferably 40 mol% or more, and even more preferably 50 mol% or more. By setting the ratio of the constituent units represented by formula (y11) in constituent unit (Y) to be above the lower limit, the balance between the solvent solubility and elastic modulus of the polyimide resin can be further improved. The upper limit of the ratio of the constituent units represented by formula (y11) in constituent unit (Y) is not particularly limited, but for example, it may be 100 mol% or less, 95 mol% or less, or 90 mol% or less.

[0074] The constituent unit (Y) may include the constituent unit (Y-2) represented by the following general formula (y2).

[0075] [ka]

[0076] In general formula (y2), Z 2 This represents a single bond, -C(=O)-, or -SO2-. * represents a bond.

[0077] Z2 This can be a single bond or a -C(=O)- bond.

[0078] The constituent unit (Y-2) may include, for example, at least one selected from the group consisting of the constituent unit represented by the following formula (y21) and the constituent unit represented by the following formula (y22).

[0079] [ka]

[0080] [ka]

[0081] In the above formula, * represents a bond.

[0082] The constituent unit (Y) may include the constituent unit represented by the following formula (y31).

[0083] [ka]

[0084] In equation (y31), * represents a bond.

[0085] In the polyimide resin of this embodiment, it is preferable that the constituent unit (X) does not have a (meth)acryloyl group, and it is preferable that the constituent unit (Y) does not have a (meth)acryloyl group. This improves the tensile elongation of the polyimide resin.

[0086] The polyimide resin is preferably a random copolymer. Being a random copolymer reduces the likelihood of structural bias within the polyimide resin molecule, resulting in a polyimide resin with good solvent solubility.

[0087] (Physical properties of polyimide resin) The physical properties of the polyimide resin of this embodiment will be described below.

[0088] The weight-average molecular weight (Mw) of the polyimide resin is preferably 5,000 to 150,000, more preferably 7,500 to 150,000, even more preferably 10,000 to 140,000, even more preferably 15,000 to 140,000, even more preferably 20,000 to 130,000, even more preferably 25,000 to 130,000, even more preferably 25,000 to 120,000, and even more preferably 25,000 to 110,000. By setting the weight-average molecular weight of the polyimide resin to be below the above upper limit, the solvent solubility of the polyimide resin can be further improved. By setting the weight-average molecular weight of the polyimide resin to be above the above lower limit, the tensile elongation of the polyimide resin can be improved.

[0089] The number-average molecular weight (Mn) of the polyimide resin may be 2,000 or more and 100,000 or less, 4,000 or more and 80,000 or less, 6,000 or more and 60,000 or less, or 8,000 or more and 40,000 or less.

[0090] The ratio of the weight-average molecular weight (Mw / Mn) to the number-average molecular weight of the polyimide resin may be 1.00 or more and 5.00 or less, 1.25 or more and 4.75 or less, or 1.50 or more and 4.50 or less.

[0091] The weight-average molecular weight and number-average molecular weight of polyimide resins are measured by gel permeation chromatography (GPC) using polystyrene as a standard substance.

[0092] In the polyimide resin of this embodiment, the storage modulus at 30°C, measured by dynamic viscoelasticity measurement (DMA) in accordance with JIS K 7244-4:1999, may be greater than 3.3 GPa and less than or equal to 20.0 GPa, 3.6 GPa or more and less than or equal to 15.0 GPa, 3.8 GPa or more and less than or equal to 10.0 GPa, or 3.9 GPa or more and less than or equal to 8.0 GPa.

[0093] In the polyimide resin of this embodiment, the glass transition temperature measured by dynamic viscoelasticity measurement (DMA) in accordance with JIS K 7244-4:1999 may be 300°C or more and 500°C or less, 310°C or more and 475°C or less, or 320°C or more and 450°C or less.

[0094] In the polyimide resin of this embodiment, the mean coefficient of linear expansion (CTE) in the range of 50°C to 100°C, measured by thermomechanical analysis (TMA) in accordance with JIS K 7197:2012, may be 15 ppm / °C or more and less than 49 ppm / °C, 20 ppm / °C or more and 45 ppm / °C or less, or 25 ppm / °C or more and 40 ppm / °C or less.

[0095] In the polyimide resin of this embodiment, the average value of the elongation at break at 23°C obtained by the following method may be 5% or more and 70% or less, 7% or more and 60% or less, or 9% or more and 50% or less.

[0096] (method) A solution is prepared by dissolving 4 g of polyimide resin in 16 g of γ-butyrolactone. The solution is spin-coated onto an 8-inch silicon wafer, and then heated at 110°C for 3 minutes to dry the solution. The spin-coating is performed so that the film thickness after drying is 10 μm. Next, the wafer is heated at 170°C for 3 hours under a nitrogen atmosphere to form a cured film. The silicon wafer with the cured film is cut to a width of 7 mm using a dicing saw. The cut silicon wafer is immersed in a 2 mass% hydrofluoric acid aqueous solution to peel off the cured film from the silicon wafer. The peeled cured film is dried at 80°C for 90 minutes to obtain a cured film. A test piece (50 mm × 7 mm × 10 μm thick) is cut from the obtained cured film. In accordance with JIS K 7197:2012, the elongation at break from the initial position to the fracture point of the test specimen is measured using a thermomechanical analyzer under air atmosphere, tensile mode, chuck distance of 20 mm, tensile speed of 5 mm / min, and 23°C. Measurements are performed on 10 test specimens, and the average value of the elongation at break is calculated.

[0097] (Method for manufacturing polyimide resin) The polyimide resin of this embodiment can be obtained, for example, by imidizing a diamine and an acidic dianhydride in an organic solvent.

[0098] The ratio (molar ratio) of the amount of diamine added to the amount of acidic dianhydride added is not particularly limited, but may be, for example, 0.70 or more and 1.30 or less.

[0099] Organic solvents are, for example, 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; Aromatic hydrocarbons such as toluene, ethylbenzene, xylene, and mesitylene; and, It may also contain at least one selected from the group consisting of ether-based solvents such as cyclopentyl methyl ether.

[0100] (varnish) The varnish of this embodiment comprises the polyimide resin and solvent of this embodiment.

[0101] The solvent may include, for example, at least one selected from the group consisting of acetone, methyl ethyl ketone, toluene, propylene glycol methyl ethyl ether, propylene glycol dimethyl ether, propylene glycol 1-monomethyl ether 2-acetate, diethylene glycol ethyl methyl ether, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, benzyl alcohol, propylene carbonate, ethylene glycol diacetate, propylene glycol diacetate, propylene glycol monomethyl ether acetate, dipropylene glycol methyl-n-propyl ether, butyl acetate, γ-butyrolactone, methyl lactate, ethyl lactate, and butyl lactate.

[0102] (Photosensitive resin composition) The photosensitive resin composition of this embodiment comprises the polyimide resin of this embodiment and a polymerization initiator.

[0103] The amount of polymerization initiator per 100 parts by mass of polyimide resin may be 1 part by mass or more and 50 parts by mass or less, 5 parts by mass or more and 40 parts by mass or less, or 10 parts by mass or more and 30 parts by mass or less.

[0104] The polymerization initiator preferably includes a photoradical generator. This allows the photosensitive resin composition to be cured by exposure.

[0105] Photoradical generators are Oxime ester-based photoradical generators such as 1-[4-(phenylthio)phenyl]octane-1,2-dione=2-(O-benzoyl oxime) and 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3-yl]ethanone 1-(O-acetyl oxime); Alkylphenone-based photoradical generators such as 2,2-dimethoxy-2-phenylacetophenone, 1-hydroxycyclohexylphenyl ketone, 2-hydroxy-2-methylpropiophenone, 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone, 2-methyl-4'-(methylthio)-2-morpholinopropiophenone, and 2-benzyl-2-(dimethylamino)-4'-morpholinobtyrophenone; and It may contain at least one selected from the group consisting of benzophenone and benzophenone-based photoradical generators such as 4,4'-bis(dimethylamino)benzophenone, and may also contain an oxime ester-based photoradical generator, and may also contain 1-[4-(phenylthio)phenyl]octane-1,2-dione=2-(O-benzoyloxime).

[0106] The amount of photoradical generator per 100 parts by mass of polyimide resin may be 1 part by mass or more and 30 parts by mass or less, or 5 parts by mass or more and 20 parts by mass or less.

[0107] The polymerization initiator preferably includes a thermal radical generator. This allows the photosensitive resin composition to be cured by heating.

[0108] The thermal radical generator may contain organic peroxides such as dicumyl peroxide, 2,5-bis(tert-butylperoxy)-2,5-dimethylhexane, and tert-butyl=2-ethylperoxyhexanoate, and may also contain dicumyl peroxide.

[0109] The amount of thermal radical generator per 100 parts by mass of polyimide resin may be 1 part by mass or more and 30 parts by mass or less, or 5 parts by mass or more and 20 parts by mass or less.

[0110] (Multifunctional (meth)acrylate) The photosensitive resin composition of this embodiment preferably further comprises a polyfunctional (meth)acrylate. This improves the curing properties of the photosensitive resin composition.

[0111] Polyfunctional (meth)acrylates are, for example, Difunctional (meth)acrylates such as polyalkylene glycol di(meth)acrylates and alkyl di(meth)acrylates; Trifunctional (meth)acrylates such as tris(2-(meth)acryloyloxyethyl) isocyanurate, optionally alkoxylated pentaerythritol tri(meth)acrylate, optionally alkoxylated trimethylolpropane tri(meth)acrylate, and alkoxylated glycerin tri(meth)acrylate; Tetrafunctional (meth)acrylates such as pentaerythritol tetra(meth)acrylate which may be alkoxylated, and ditrimethylolpropane tetra(meth)acrylate which may be alkoxylated; and It comprises at least one selected from the group consisting of five or more functional (meth)acrylates, such as dipentaerythritol penta(meth)acrylate which may be alkoxylated, and dipentaerythritol hexa(meth)acrylate which may be alkoxylated.

[0112] The content of polyfunctional (meth)acrylate per 100 parts by mass of polyimide resin is preferably 20 parts by mass or more and 150 parts by mass or less, more preferably 25 parts by mass or more and 100 parts by mass or less, and even more preferably 30 parts by mass or more and 75 parts by mass or less. By setting the content of polyfunctional (meth)acrylate per 100 parts by mass of polyimide resin within the above range, the balance between the photosensitivity of the photosensitive resin composition and the mechanical properties of the photosensitive resin composition after curing can be improved.

[0113] The polyfunctional (meth)acrylate preferably includes five or more functional (meth)acrylates, and more preferably includes at least one selected from the group consisting of dipentaerythritol penta(meth)acrylate and dipentaerythritol hexa(meth)acrylate. This improves the photosensitivity of the photosensitive resin composition. It also improves the chemical resistance of the photosensitive resin composition after curing.

[0114] The content of 5- or more functional (meth)acrylate per 100 parts by mass of polyimide resin is preferably more than 0 parts by mass and 100 parts by mass or less, more preferably 5 parts by mass or more and 80 parts by mass or less, even more preferably 10 parts by mass or more and 70 parts by mass or less, even more preferably 15 parts by mass or more and 65 parts by mass or less, and even more preferably 20 parts by mass or more and 60 parts by mass or less. By setting the content of 5- or more functional (meth)acrylate per 100 parts by mass of polyimide resin to be above the lower limit, the photosensitivity of the photosensitive resin composition can be improved. In addition, the chemical resistance of the photosensitive resin composition after curing can be improved. By setting the content of 5- or more functional (meth)acrylate per 100 parts by mass of polyimide resin to be below the upper limit, the tensile elongation of the photosensitive resin composition after curing can be improved.

[0115] The content of five- or more functional (meth)acrylates per 100 parts by mass of polyfunctional (meth)acrylate is preferably 30 parts by mass or more and 100 parts by mass or less, more preferably 40 parts by mass or more and 99 parts by mass or less, and even more preferably 50 parts by mass or more and 98 parts by mass or less. By setting the content of five- or more functional (meth)acrylates per 100 parts by mass of polyfunctional (meth)acrylate to be above the lower limit, the photosensitivity of the photosensitive resin composition can be improved. Furthermore, the chemical resistance of the photosensitive resin composition after curing can be improved. By setting the content of five- or more functional (meth)acrylates to be below the upper limit, the tensile elongation of the photosensitive resin composition after curing can be improved.

[0116] The polyfunctional (meth)acrylate preferably includes a (meth)acrylate with two to four functionalities, and more preferably a (meth)acrylate with two or three functionalities. This improves the tensile elongation of the photosensitive resin composition after curing.

[0117] The content of bifunctional to tetrafunctional (meth)acrylate per 100 parts by mass of polyimide resin is preferably more than 0 parts by mass and 25 parts by mass or less, more preferably 1 part by mass and 20 parts by mass or less, and even more preferably 2 parts by mass and 15 parts by mass or less. By setting the content of bifunctional to tetrafunctional (meth)acrylate per 100 parts by mass of polyimide resin within the above range, the mechanical properties of the photosensitive resin composition after curing can be improved.

[0118] The content of bifunctional to tetrafunctional (meth)acrylate per 100 parts by mass of polyfunctional (meth)acrylate is preferably greater than 0 parts by mass and 70 parts by mass or less, more preferably 1 part by mass and 50 parts by mass or less, and even more preferably 2 parts by mass and 40 parts by mass or less. By setting the content of bifunctional to tetrafunctional (meth)acrylate per 100 parts by mass of polyfunctional (meth)acrylate within the above range, the mechanical properties of the photosensitive resin composition after curing can be improved.

[0119] The polyfunctional (meth)acrylate may include polyalkylene glycol di(meth)acrylate, at least one selected from the group consisting of polyethylene glycol di(meth)acrylate and polypropylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, at least one selected from the group consisting of diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate and tetraethylene glycol di(meth)acrylate, and triethylene glycol di(meth)acrylate.

[0120] Polyfunctional (meth)acrylates may include (meth)acrylates having an isocyanurate skeleton.

[0121] The (meth)acrylate having an isocyanurate skeleton may include, for example, at least one selected from the group consisting of tris(2-(meth)acryloyloxyethyl)isocyanurate and 2-hydroxyethylbis(2-(meth)acryloyloxyethyl)isocyanurate, and may also include tris(2-(meth)acryloyloxyethyl)isocyanurate.

[0122] (Epoxy compound) The photosensitive resin composition of this embodiment preferably further comprises an epoxy compound. The epoxy compound is a compound having epoxy groups. It is believed that the epoxy groups of the epoxy compound react with the acid anhydride groups, which are terminal groups of the polyimide resin, to form ester bonds, thereby improving the tensile elongation of the photosensitive resin composition after curing.

[0123] The content of the epoxy compound per 100 parts by mass of polyimide resin is preferably 0.1 parts by mass or more and 25 parts by mass or less, more preferably 0.5 parts by mass or more and 20 parts by mass or less, and even more preferably 1 part by mass or more and 15 parts by mass or less. By setting the content of the epoxy compound per 100 parts by mass of polyimide resin within the above range, the balance between the tensile elongation and heat resistance after curing of the photosensitive resin composition can be improved.

[0124] The epoxy compound preferably includes an epoxy compound having a (meth)acryloyl group. It is believed that the epoxy compound having a (meth)acryloyl group polymerizes with the polyfunctional (meth)acrylate, resulting in crosslinking between the polyfunctional (meth)acrylate and the polyimide resin. This is thought to further improve the mechanical properties of the photosensitive resin composition after curing.

[0125] The epoxy compound having a (meth)acryloyl group may include, for example, at least one selected from the group consisting of 4-hydroxybutyl (meth)acrylate glycidyl ether, glycidyl (meth)acrylate, and (3,4-epoxycyclohexyl)methyl (meth)acrylate, and may also include 4-hydroxybutyl (meth)acrylate glycidyl ether.

[0126] (Silane coupling agent) The photosensitive resin composition of this embodiment preferably further comprises a silane coupling agent. This improves the adhesion between the cured photosensitive resin composition and the adherend (e.g., a substrate).

[0127] Silane coupling agents include, for example, Silane coupling agents having a cyclic anhydride structure, such as 3-trimethoxysilylpropyl succinic anhydride, 3-triethoxysilylpropyl succinic anhydride, and 3-dimethylmethoxysilylpropyl succinic anhydride; (meth)acrylsilanes such as 3-(meth)acryloyloxypropyltrimethoxysilane, 3-(meth)acryloyloxypropylmethyldimethoxysilane, 3-(meth)acryloyloxypropylmethyldiethoxysilane, and 3-(meth)acryloyloxypropyltriethoxysilane; Epoxysilanes such as 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, and 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane; Aminosilanes such as N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, and 3-triethoxysilyl-N-(1,3-dimethylbutylidene)propylamine; Mercaptosilanes such as 3-mercaptopropylmethyldimethoxysilane and 3-mercaptopropyltrimethoxysilane; Vinylsilanes such as vinyltrimethoxysilane and vinyltriethoxysilane; and, It contains at least one selected from the group consisting of ureidosilanes, such as 3-ureidopropyltrialkoxysilane.

[0128] The content of the silane coupling agent per 100 parts by mass of polyimide resin is preferably 0.1 parts by mass or more and 10 parts by mass or less, more preferably 1 part by mass or more and 8 parts by mass or less, and even more preferably 2 parts by mass or more and 7 parts by mass or less. By setting the content of the silane coupling agent per 100 parts by mass of polyimide resin within the above range, the adhesion between the cured product of the photosensitive resin composition and the adherend (e.g., substrate) can be improved.

[0129] The silane coupling agent preferably includes a silane coupling agent having a cyclic anhydride structure. It is believed that the cyclic anhydride structure reacts with amino groups, which are terminal groups of the polyimide resin, or with epoxy compounds, thereby improving the adhesion between the cured photosensitive resin composition and the adherend (e.g., substrate).

[0130] The silane coupling agent having a cyclic anhydride structure may contain at least one selected from the group consisting of 3-trimethoxysilylpropyl succinic anhydride, 3-triethoxysilylpropyl succinic anhydride, and 3-dimethylmethoxysilylpropyl succinic anhydride, and may also contain 3-trimethoxysilylpropyl succinic anhydride.

[0131] The content of the silane coupling agent having a cyclic anhydride structure per 100 parts by mass of polyimide resin is preferably 0.1 parts by mass or more and 10 parts by mass or less, more preferably 0.5 parts by mass or more and 7.5 parts by mass or less, and even more preferably 1 part by mass or more and 5 parts by mass or less. By setting the content of the silane coupling agent having a cyclic anhydride structure per 100 parts by mass of polyimide resin within the above range, the adhesion between the cured product of the photosensitive resin composition and the adherend (e.g., substrate) can be improved.

[0132] The silane coupling agent preferably contains (meth)acrylicsilane. It is believed that the polymerization of (meth)acrylicsilane with polyfunctional (meth)acrylate can improve the adhesion between the cured photosensitive resin composition and the adherend (e.g., substrate).

[0133] (Meth)acrylsilane may contain at least one selected from the group consisting of 3-(meth)acryloyloxypropyltrimethoxysilane, 3-(meth)acryloyloxypropylmethyldimethoxysilane, 3-(meth)acryloyloxypropylmethyldiethoxysilane, and 3-(meth)acryloyloxypropyltriethoxysilane, and may also contain 3-(meth)acryloyloxypropyltrimethoxysilane.

[0134] The content of (meth)acrylsilane per 100 parts by mass of polyimide resin is preferably 0.1 parts by mass or more and 10 parts by mass or less, more preferably 0.5 parts by mass or more and 7.5 parts by mass or less, and even more preferably 1 part by mass or more and 5 parts by mass or less. By setting the content of (meth)acrylsilane per 100 parts by mass of polyimide resin within the above range, the adhesion between the cured product of the photosensitive resin composition and the adherend (e.g., substrate) can be improved.

[0135] (Adhesion enhancer) The photosensitive resin composition of this embodiment preferably further contains an adhesion aid. This improves the adhesion between the cured photosensitive resin composition and the adherend (e.g., a substrate).

[0136] The adhesion aids include, for example, nitrogen atom-containing heteroaromatic compounds having at least one group selected from the group consisting of (1H-tetrazol-5-yl)amino group, 1-(1H-tetrazol-5-yl)methyl-amino group, 3-(1H-tetrazol-5-yl)benz-amino group, 1-(5-1H-triazol)methylamino group, 3-(1H-pyrazoyl)amino group, 4-(1H-pyrazoyl)amino group, 5-(1H-pyrazoyl)amino group, 1-(3-1H-pyrazoyl)methylamino group, 1-(4-1H-pyrazoyl)methylamino group, and 1-(5-1H-pyrazoyl)methylamino group.

[0137] The content of the adhesion aid per 100 parts by mass of polyimide resin is preferably 0.1 parts by mass or more and 10 parts by mass or less, more preferably 1 part by mass or more and 5 parts by mass or less. By setting the content of the adhesion aid per 100 parts by mass of polyimide resin within the above range, the adhesion between the cured product of the photosensitive resin composition and the adherend (e.g., substrate) can be improved.

[0138] (curing catalyst) The photosensitive resin composition of this embodiment preferably further comprises a curing catalyst. This can accelerate the curing reaction of the photosensitive resin composition. In particular, the photosensitive resin composition of this embodiment preferably further comprises an epoxy compound and a curing catalyst. By including a curing catalyst in the photosensitive resin composition, the reaction between the epoxy groups of the epoxy compound and the acid anhydride groups, which are terminal groups of the polyimide resin, proceeds sufficiently, and the tensile elongation of the photosensitive resin composition after curing can be improved.

[0139] The curing catalyst is Phosphonium salts such as tetraphenylphosphonium·4,4'-sulfonyl diphenolate, tetraphenylphosphonium·tetraphenylborate, and tetraphenylphosphonium bromide; Phosphines such as triphenylphosphine and methyldiphenylphosphine; Tertiary amines and tertiary amine salts such as 1,8-diazabicyclo[5.4.0]-7-undecene, 1,5-diazabicyclo[4.3.0]-5-nonene, and 2,4,6-tris(dimethylaminomethyl)phenol; and, It may contain at least one selected from the group consisting of imidazoles such as 1-(2-cyanoethyl)-2-ethyl-4-methylimidazole and 2-ethyl-4-methylimidazole, and may also contain a phosphonium salt, or tetraphenylphosphonium·4,4'-sulfonyl diphenolate.

[0140] The content of the curing catalyst per 100 parts by mass of polyimide resin may be 1 part by mass or more and 50 parts by mass or less, or 5 parts by mass or more and 30 parts by mass or less.

[0141] (Antioxidant) The photosensitive resin composition of this embodiment preferably further contains an antioxidant. This helps to suppress the degradation of the photosensitive resin composition.

[0142] The antioxidant includes, for example, at least one selected from the group consisting of hindered phenol antioxidants such as tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)isocyanuric acid and 2,2'-methylenebis(6-tert-butyl-4-ethylphenol), and thioether antioxidants such as pentaerythritol tetrakis[3-laurylthiopropionate].

[0143] The amount of antioxidant per 100 parts by mass of polyimide resin may be 0.1 parts by mass or more and 10 parts by mass or less, or 1 part by mass or more and 5 parts by mass or less.

[0144] (Surfactants) The photosensitive resin composition of this embodiment preferably further contains a surfactant. This improves the applicability of the photosensitive resin composition.

[0145] Surfactants are, for example, Silicone-based surfactants such as polyether-modified siloxanes, polyester-modified siloxanes, and aralkyl-modified siloxanes; 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; and, It includes at least one selected from the group consisting of fluorine-based surfactants.

[0146] The amount of surfactant per 100 parts by mass of polyimide resin may be 0.01 parts by mass or more and 1 part by mass or less, or 0.05 parts by mass or more and 0.5 parts by mass or less.

[0147] (solvent) The photosensitive resin composition of this embodiment preferably further contains a solvent. This improves the coatability of the photosensitive resin composition.

[0148] The solvent includes, for example, at least one selected from the group consisting of acetone, methyl ethyl ketone, toluene, propylene glycol methyl ethyl ether, propylene glycol dimethyl ether, propylene glycol 1-monomethyl ether 2-acetate, diethylene glycol ethyl methyl ether, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, benzyl alcohol, propylene carbonate, ethylene glycol diacetate, propylene glycol diacetate, propylene glycol monomethyl ether acetate, dipropylene glycol methyl-n-propyl ether, butyl acetate, γ-butyrolactone, methyl lactate, ethyl lactate, and butyl lactate.

[0149] If the photosensitive resin composition of this embodiment further contains a solvent, the total solid content (non-volatile component) in the photosensitive resin composition may be 10% by mass or more and 50% by mass or less.

[0150] (Physical properties of photosensitive resin compositions) The physical properties of the photosensitive resin composition of this embodiment will be described below.

[0151] According to JIS K 7244-4:1999, the storage modulus at 23°C of a cured product obtained by curing a photosensitive resin composition at 170°C for 3 hours, as measured by dynamic viscoelasticity measurement (DMA), is preferably greater than 2.8 GPa and less than or equal to 20.0 GPa, more preferably between 3.2 GPa and 15.0 GPa, even more preferably between 3.5 GPa and 10.0 GPa, and even more preferably between 3.8 GPa and 8.0 GPa. Having the storage modulus at 23°C within the above range improves the rigidity and strength of the cured photosensitive resin composition, thereby suppressing crack formation during the manufacture of semiconductor devices.

[0152] The glass transition temperature (Tg) of a cured product obtained by curing a photosensitive resin composition at 170°C for 3 hours is measured by dynamic viscoelasticity measurement (DMA) in accordance with JIS K 7244-4:1999. DMA The temperature is preferably more than 313°C and 500°C or less, more preferably 320°C to 475°C, and even more preferably 325°C to 450°C. In this embodiment, Tg DMA This is thought to mainly reflect the glass transition temperature of the polyimide resin. DMA As long as the above range is maintained, it is possible to manufacture semiconductor devices with small dimensional changes during high-temperature reflow processing and good connection reliability.

[0153] The glass transition temperature (Tg) of a cured product obtained by curing a photosensitive resin composition at 170°C for 3 hours is measured by thermomechanical analysis (TMA) in accordance with JIS K 7197:2012. TMA The temperature is preferably between 259°C and 500°C, more preferably between 265°C and 475°C, and even more preferably between 270°C and 450°C. In this embodiment, Tg TMA This is thought to mainly reflect the glass transition temperature of the cured polyfunctional (meth)acrylate.TMA As long as the above range is maintained, it is possible to manufacture semiconductor devices with minimal film thickness changes due to chemical treatment.

[0154] In accordance with JIS K 7244-4:1999, the glass transition temperature (Tg) of a cured product obtained by curing a photosensitive resin composition at 170°C for 3 hours is measured by dynamic viscoelasticity measurement (DMA). DMA The glass transition temperature (Tg) of the cured product obtained by curing a photosensitive resin composition at 170°C for 3 hours is determined by thermomechanical analysis (TMA) in accordance with JIS K 7197:2012. TMA Let's assume that. Tg DMA -Tg TMA The temperature is preferably 35°C to 100°C, more preferably 40°C to 90°C, and even more preferably 45°C to 80°C. In this embodiment, Tg DMA -Tg TMA The magnitude of the value is considered to be an indicator of the magnitude of the glass transition temperature of the polyimide resin relative to the glass transition temperature of the cured polyfunctional (meth)acrylate. DMA -Tg TMA By keeping the above range, it is possible to achieve both tensile elongation and elastic modulus after curing of the photosensitive resin composition, thereby enabling the manufacture of semiconductor devices with good connection reliability.

[0155] In accordance with JIS K 7197:2012, the mean linear thermal expansion coefficient (CTE) of a cured product obtained by curing a photosensitive resin composition at 170°C for 3 hours, measured by thermomechanical analysis (TMA), is preferably 20 ppm / °C or more and less than 61 ppm / °C, more preferably 25 ppm / °C or more and 58 ppm / °C or less, and even more preferably 30 ppm / °C or more and 55 ppm / °C or less. Having a CTE within this range suppresses warping of the semiconductor device, enabling the manufacture of a semiconductor device with good connection reliability.

[0156] The average value of the elongation at break at 23°C of the cured product obtained by curing the photosensitive resin composition obtained by the following method at 170°C for 3 hours is preferably 8% to 80%, more preferably 10% to 70%, and even more preferably 15% to 60%. Having the average elongation at break at 23°C within this range suppresses the occurrence of cracks during the manufacturing of semiconductor devices, enabling the production of semiconductor devices with good connection reliability.

[0157] (method) A test specimen (50 mm × 7 mm × 10 μm thick) is cut from the cured material. In accordance with JIS K 7197:2012, the elongation at break from the initial position to the breaking point of the test specimen is measured using a thermomechanical analyzer under air atmosphere, tensile mode, chuck distance of 20 mm, tensile speed of 5 mm / min, and 23°C. Measurements are performed on 10 test specimens, and the average value of the elongation at break is calculated.

[0158] (Method for preparing a photosensitive resin composition) The photosensitive resin composition of this embodiment can be prepared, for example, by obtaining a polyimide resin by imidizing a diamine and an acidic dianhydride in an organic solvent, and then mixing the above-mentioned components in a solvent.

[0159] (Uses of photosensitive resin compositions) The photosensitive resin composition of this embodiment is preferably used in semiconductor devices. It is preferably used to form a resin film for semiconductor devices, and more preferably to form a permanent film. The permanent film is used as a protective film, interlayer film, dam material, etc., in semiconductor devices.

[0160] (cured product) The cured product of this embodiment is a cured product of the photosensitive resin composition of this embodiment. The cured product of this embodiment can be obtained, for example, by applying the photosensitive resin composition of this embodiment to a substrate, pre-baking to dry and form a resin film, then exposing and developing the resin film to a desired shape, and finally post-baking to cure it. Pre-baking may be, for example, a heat treatment at 90°C to 130°C for 30 seconds to 1 hour. Post-baking may be, for example, a heat treatment at 150°C to 250°C for 30 minutes to 10 hours.

[0161] (Semiconductor device) The semiconductor device of this embodiment includes the cured product of this embodiment. More specifically, the semiconductor device of this embodiment may include an interlayer insulating film, a resin film containing the cured product of this embodiment on the interlayer insulating film, and rewiring embedded in the resin film.

[0162] Figure 1 is a schematic cross-sectional view illustrating an example of the structure of a semiconductor device according to this embodiment. As shown in Figure 1, the semiconductor device 100 of this embodiment comprises a semiconductor substrate on which semiconductor elements such as transistors are provided, and a multilayer wiring layer (not shown) provided on the semiconductor substrate. The uppermost layer of the multilayer wiring layer is provided with an interlayer insulating film 30 and an uppermost wiring 34 provided on the interlayer insulating film 30. A passivation film 32 is provided on the interlayer insulating film 30 and the uppermost wiring 34. An opening is provided in a part of the passivation film 32 to expose the uppermost wiring 34. A rewiring layer 40 is provided on the passivation film 32. The rewiring layer 40 includes an insulating layer 42 provided on the passivation film 32, 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 is formed in the insulating layer 42 that connects to the uppermost wiring 34. The rewiring 46 is formed on the insulating layer 42 and within openings provided in the insulating layer 42, and is connected to the uppermost wiring 34. The insulating layer 44 is provided with openings for connection to the rewiring 46. Within the openings provided in the insulating layer 44, for example, bumps 52 are formed via a UBM (Under Bump Metallurgy) layer 50. The semiconductor device 100 is connected to a wiring board or the like via, for example, the bumps 52.

[0163] In the semiconductor device 100, at least one selected from the group consisting of a passivation film 32, an insulating layer 42, and an insulating layer 44 may be a resin film containing the cured product of this embodiment. The resin film may be a permanent film.

[0164] The semiconductor device 100 may be a semiconductor chip. In this case, for example, a semiconductor package can be obtained by mounting the semiconductor device 100 on a wiring board via bumps 52.

[0165] Although embodiments of the present invention have been described above, these are merely examples, and various other configurations can be adopted. Furthermore, the present invention is not limited to the embodiments described above, and modifications, improvements, etc., within the scope that can achieve the objectives of the present invention are included in the present invention. [Examples]

[0166] The present invention will be described in detail below with reference to examples. However, the present invention is not limited in any way to the descriptions in these examples.

[0167] (1) Raw materials The raw materials used in each example and comparative example are shown below.

[0168] (Diamine) OTBAF: 9,9-bis(4-amino-3-methylphenyl)fluorene, represented by the following formula. [ka]

[0169] BPF-AN: Represented by the following formula, 9,9-bis[4-(4-aminophenoxy)phenyl]fluorene [ka]

[0170] DABA: 3,5-diaminobenzoic acid, represented by the following formula. [ka]

[0171] TSN: 3,7-diamino-2,8-dimethyldibenzothiofensulfone, represented by the following formula. [ka]

[0172] BAPP: 2,2-bis[4-(4-aminophenoxy)phenyl]propane, represented by the following formula. [ka]

[0173] MED-J: 4,4-Diamino-3,3-diethyl-5,5-dimethyldiphenylmethane represented by the following formula [Chemical formula]

[0174] 1,5-DAN: 1,5-Diaminonaphthalene represented by the following formula [Chemical formula]

[0175] (Dianhydride) TMPBP-TME: 2,2’,3,3’,5,5’-Hexamethyl[1,1’-biphenyl]-4,4’-diyl bis(1,3-dioxo-1,3-dihydro-2-benzofuran-5-carboxylate) (manufactured by Honshu Chemical Industry Co., Ltd.) represented by the following formula [Chemical formula]

[0176] BTDA: 3,3’,4,4’-Benzophenonetetracarboxylic dianhydride represented by the following formula [Chemical formula]

[0177] s-BPDA: 3,3’,4,4’-Biphenyltetracarboxylic dianhydride represented by the following formula [Chemical formula]

[0178] PMDA: Pyromellitic dianhydride represented by the following formula [Chemical formula]

[0179] (2) Synthesis of polyimide resin In a flask equipped with a Dean-Stark apparatus, 9 g of diamine, 11 g of acidic dianhydride, and solvents (88 g of 3-methyl-2-oxazolidone and 16 g of cyclopentyl methyl ether) were added. The starting material compositions of the diamine and acidic dianhydride are shown in Table 1 (units are molar ratios). The mixture was then stirred at room temperature for 10 minutes under a nitrogen atmosphere, and then heated in an oil bath and reacted at 150°C for 1 hour. 3 g of 2,6-lutidine was added as a dehydration catalyst, and the reaction was further carried out at 190°C for 4 hours. After the reaction solution was cooled to room temperature, it was diluted with tetrahydrofuran, and isopropanol was added dropwise to precipitate a solid. The obtained solid was filtered, washed, and vacuum-dried at 60°C to obtain a polyimide resin.

[0180] (3) Evaluation of polyimide resins (Measurement of number-average molecular weight and weight-average molecular weight of polyimide resins) A diluent was obtained by diluting 0.05 g of polyimide resin with 0.95 g of γ-butyrolactone. 0.1 g of the diluent was diluted with 1.9 g of tetrahydrofuran to prepare a sample for measurement. The number-average molecular weight (Mn) and weight-average molecular weight (Mw) of the polyimide resin were measured by gel permeation chromatography (GPC) using a Tosoh HLC-8420GPC with tetrahydrofuran as the eluent. A Tosoh TSKgel SuperMultiporeHZ-H column was used. Polystyrene (Tosoh PStQuick C and PStQuick D) was used as the standard material.

[0181] (Preparation of cured polyimide resin films) A solution was prepared by dissolving 4 g of polyimide resin in 16 g of γ-butyrolactone. The solution was spin-coated onto an 8-inch silicon wafer, and then heated at 110°C for 3 minutes to dry the solution. The spin-coating was performed to achieve a film thickness of 10 μm after drying. Next, the wafer was heated at 170°C for 3 hours under a nitrogen atmosphere to form a cured film. The silicon wafer with the cured film was cut into 7 mm wide strips using a dicing saw. The cut silicon wafer was immersed in a 2% by mass aqueous hydrofluoric acid solution to peel off the cured film from the silicon wafer. The peeled cured film was dried at 80°C for 90 minutes to obtain a cured film.

[0182] (Dynamic viscoelasticity measurement) A test specimen (30 mm × 7 mm × 10 μm thick) was cut from the obtained cured film. Dynamic viscoelasticity measurements (DMA) were performed using a dynamic viscoelasticity analyzer (TA Instruments "Q800") in accordance with JIS K 7244-4:1999, under the conditions of an air atmosphere, frequency of 1 Hz, tensile mode, heating rate of 5 °C / min, chuck distance of 20 mm, and heating from 30 °C to 400 °C. The storage modulus at 30 °C was read from the obtained temperature-storage modulus (E') graph. In addition, the temperature at which the loss tangent (tanδ) was maximum in the obtained temperature-storage tangent (tanδ) graph was defined as the glass transition temperature (Tg).

[0183] (Measurement of mean linear thermal expansion coefficient) A test specimen (20 mm × 4 mm × 10 μm thick) was cut from the obtained cured film. Thermomechanical analysis (TMA) was performed in accordance with JIS K 7197:2012 using a thermomechanical analyzer (Hitachi High-Tech Corporation "TMA-7100C") under nitrogen atmosphere, tensile mode, heating rate of 10 °C / min, chuck distance of 10 mm, and heating from 30 °C to 400 °C. The mean coefficient of linear expansion (CTE) in the range of 50 °C to 100 °C was determined from the obtained temperature-displacement graph.

[0184] (Measurement of elongation at break) A test specimen (50 mm × 7 mm × 10 μm thick) was cut from the obtained cured film. In accordance with JIS K 7197:2012, the elongation at break from the initial position to the breaking point of the test specimen was measured using a thermomechanical analyzer (A&D Corporation "STB-1225S") under the conditions of air atmosphere, tensile mode, chuck distance of 20 mm, tensile speed of 5 mm / min, and 23°C. Measurements were performed on 10 test specimens, and the average value of the elongation at break was calculated.

[0185] (Evaluation of solvent solubility) A solution was prepared by dissolving 4 g of polyimide resin in 16 g of γ-butyrolactone. The solution was allowed to stand at 25°C for 3 hours to stabilize its temperature. While measuring the viscosity of the solution using a viscometer (TV-25 viscometer, cone-plate type, manufactured by Toki Sangyo Co., Ltd.), γ-butyrolactone was further added to the solution and diluted until the viscosity reached 2000 ± 200 mPa·s to obtain a solution for solubility evaluation. The solution for solubility evaluation was filtered under pressure with nitrogen gas for 30 minutes using a 3M Lab Scale Filter Disc DP Series (NM04711 BF100) (material: polypropylene, filtration accuracy: 10.0 μm) as a filter. The presence or absence of residue on the filter after filtration was visually confirmed, and the solvent solubility of the polyimide resin was evaluated according to the following criteria. A: No residue was found. B: Residue was found.

[0186] (Evaluation of compatibility with (meth)acrylate) A solution was prepared by dissolving 100 parts by mass of polyimide resin in 600 parts by mass of γ-butyrolactone, then adding and mixing 50 parts by mass of dipentaerythritol polyacrylate (A-DPH, manufactured by Shin-Nakamura Chemical Industry Co., Ltd.). The solution was visually observed, and the compatibility of the polyimide resin with (meth)acrylate was evaluated according to the following criteria. A: The solution was clear. B: The solution was cloudy.

[0187] Table 1 shows the evaluation results for each example and comparative example.

[0188]

Table 1

[0189] (4) Preparation of the photosensitive resin composition The polyimide resin was synthesized in the same manner as in (2) above. The raw material compositions of the diamine and the dianhydride are shown in Table 2 (unit: molar ratio). Next, each raw material was mixed in a solvent to prepare a photosensitive resin composition. The raw materials other than the polyimide resin and the types of the solvents are shown below. The blending amounts of the raw materials other than the polyimide resin and the solvents are shown in Table 2. The blending amounts of each raw material and the solvent are the blending amounts relative to 100 parts by mass of the polyimide resin.

[0190] Photoinitiator 1: 1-[4-(phenylthio)phenyl]octane-1,2-dione 2-(O-benzoyloxime) represented by the following formula (「Irgacure OXE01」manufactured by BASF Japan Ltd.)

Chemical formula

[0191] Photoinitiator 2: Dicumyl peroxide represented by the following formula (「Perkadox BC-FF」manufactured by Kayaku Nouryon Co., Ltd.)

Chemical formula

[0192] Polyfunctional (meth)acrylate: Polyfunctional acrylate compound represented by the following formula (「Viscoat #802」manufactured by Osaka Organic Chemical Industry Co., Ltd.)

Chemical formula

[0193] Epoxy compound 1: 4-hydroxybutyl acrylate glycidyl ether represented by the following formula (「4HBAGE」manufactured by Shinryo Corporation)

Chemical formula

[0194] Epoxy compound 2: A trifunctional epoxy compound represented by the following formula (Printec Co., Ltd.'s "VG3101L") [ka]

[0195] Silane coupling agent 1: 3-trimethoxysilylpropyl succinic anhydride (Shin-Etsu Chemical Co., Ltd. "X-12-967C") represented by the following formula. [ka]

[0196] Silane coupling agent 2: 3-methacryloyloxypropyltrimethoxysilane (Shin-Etsu Chemical Co., Ltd. "KBM-503"), represented by the following formula. [ka]

[0197] Adhesion enhancer: 5-aminotetrazol monohydrate (manufactured by Masuda Chemical Industries Co., Ltd.) Curing catalyst: Tetraphenylphosphonium·4,4'-sulfonyl diphenolate (manufactured by Sumitomo Bakelite Co., Ltd.), represented by the following formula. [ka]

[0198] Antioxidant: Tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)isocyanuric acid (KEMINOX179, manufactured by Chemipro Chemical Co., Ltd.), represented by the following formula. [ka]

[0199] Surfactant: Polyether-modified siloxane (BYK-349, manufactured by BYK) Solvent: γ-Butyrolactone (manufactured by Sanwa Oil & Chemical Industry Co., Ltd.)

[0200] (5) Evaluation of photosensitive resin composition (Preparation of hardened material) The photosensitive resin composition was spin-coated onto an 8-inch silicon wafer, and then heated at 110°C for 3 minutes to dry the photosensitive resin composition (pre-bake). The spin-coating was performed to achieve a film thickness of 10 μm after drying. Subsequently, a high-pressure mercury lamp was used to apply 600 mJ / cm² of heat. 2 The silicon wafer was exposed to light and then heated at 170°C for 3 hours under a nitrogen atmosphere to cure it (post-bake). The silicon wafer was cut to a width of 7 mm using a dicing saw. The cut silicon wafer was immersed in a 2 mass% hydrofluoric acid aqueous solution and the cured material was peeled off the silicon wafer. The peeled cured material was dried at 80°C for 90 minutes to obtain a cured product.

[0201] (Dynamic viscoelasticity measurement) A test specimen (30 mm × 7 mm × 10 μm thick) was cut from the obtained cured material. Dynamic viscoelasticity (DMA) measurements were performed using a dynamic viscoelasticity analyzer (TA Instruments "Q800") in accordance with JIS K 7244-4:1999, under the conditions of air atmosphere, frequency 1 Hz, tensile mode, heating rate 5 °C / min, chuck distance 20 mm, and 23 °C, to measure the storage modulus at 23 °C. Furthermore, dynamic viscoelasticity (DMA) measurements were performed under conditions of heating from 23 °C to 400 °C. In the obtained temperature-loss tangent (tanδ) graph, the temperature at which the loss tangent (tanδ) was maximum was defined as the glass transition temperature (Tg). DMA )

[0202] (Thermomechanical analysis) A test specimen (20 mm × 4 mm × 10 μm thick) was cut from the obtained cured material. Thermomechanical analysis (TMA) was performed in accordance with JIS K 7197:2012 using a thermomechanical analyzer (Hitachi High-Tech Corporation "TMA-7100C") under nitrogen atmosphere, tensile mode, heating rate of 10 °C / min, chuck distance of 10 mm, and heating from 23 °C to 400 °C. The glass transition temperature (Tg) was determined from the obtained temperature-displacement graph. TMA ), and the mean coefficient of linear thermal expansion (CTE) in the range of 50°C to 100°C were determined.

[0203] (Measurement of elongation at break) From the resulting cured material, test specimens (50 mm × 7 mm × 10 μm thick) were cut out. In accordance with JIS K 7197:2012, a thermomechanical analyzer (A&D Co., Ltd. "STB-1225S") was used to measure the elongation at break from the initial position of the test specimen to the point of fracture under the conditions of air atmosphere, tensile mode, chuck distance of 20 mm, tensile speed of 5 mm / min, and 23°C. Measurements were performed on 10 test specimens, and the average value of the elongation at break was calculated.

[0204] [Table 2] [Explanation of Symbols]

[0205] 30 Interlayer insulating film 32 Passivation membrane 34 Top layer wiring 40 Redistribution layer 42 Insulating layer 44 Insulating layer 46 Rewiring 50 UBM layers 52 Bump 100 Semiconductor Equipment

Claims

1. A polyimide resin containing a constituent unit represented by the following general formula (1). 【Chemistry 1】 (In general formula (1), X represents a divalent organic group (X) and Y represents a tetravalent organic group (Y), The aforementioned constituent unit (X) includes the constituent unit (X-1) represented by the following general formula (x1). 【Chemistry 2】 (In general formula (x1), R １ Each of these independently represents an alkyl group having 1 to 4 carbon atoms. a and b each independently represent integers from 0 to 4. * indicates a bonding operation.

2. The polyimide resin according to claim 1, wherein the aforementioned constituent unit (Y) includes a constituent unit (Y-1) represented by the following general formula (y1). 【Transformation 3】 (In general formula (y1), R ５ Each of these independently represents an alkyl group having 1 to 4 carbon atoms. Z １ This represents a single bond or a divalent organic group. g and h each independently represent integers from 0 to 4. * indicates a bonding operation.

3. The polyimide resin according to claim 2, wherein the ratio of the constituent unit (Y-1) in the constituent unit (Y) is 10 mol% or more.

4. The polyimide resin according to any one of claims 1 to 3, wherein the constituent unit (Y) includes a constituent unit (Y-2) represented by the following general formula (y2). 【Chemistry 4】 (In general formula (y2), Z ２ This is a single bond, -C(=O)-, or -SO ２ - represents, * indicates a bonding operation.

5. The polyimide resin according to any one of claims 1 to 3, wherein the constituent unit (X) further comprises a constituent unit (X-2) represented by the following general formula (x2). 【Transformation 5】 (In general formula (x2), R ２ Each of these independently represents an alkyl group having 1 to 4 carbon atoms. c and d each independently represent integers from 0 to 4. * indicates a bonding operation.

6. The polyimide resin according to any one of claims 1 to 3, wherein the aforementioned constituent unit (X) further comprises a constituent unit (X-3) represented by the following general formula (x3). 【Transformation 6】 (In the general formula (x3), * represents a bond.)

7. The polyimide resin according to any one of claims 1 to 3, wherein the aforementioned constituent unit (X) further comprises a constituent unit (X-4) represented by the following general formula (x4). 【Transformation 7】 (In general formula (x4), R ３ Each of these independently represents an alkyl group having 1 to 4 carbon atoms. e and f each independently represent integers from 0 to 3. * indicates a bonding operation.

8. The polyimide resin according to any one of claims 1 to 3, wherein the constituent unit (X) further comprises a constituent unit (X-5) represented by the following general formula (x5). 【Transformation 8】 (In general formula (x5), R ４ Each of these independently represents either a methyl group or a trifluoromethyl group. * indicates a bonding operation.

9. The polyimide resin according to any one of claims 1 to 3, wherein the weight-average molecular weight of the polyimide resin is 5,000 or more and 150,000 or less.

10. A polyimide resin according to any one of claims 1 to 3, wherein the storage modulus at 30°C is greater than 3.3 GPa, as measured by dynamic viscoelasticity measurement (DMA) in accordance with JIS K 7244-4:1999.

11. A polyimide resin according to any one of claims 1 to 3, wherein the glass transition temperature, as measured by dynamic viscoelastic analysis (DMA) in accordance with JIS K 7244-4:1999, is 300°C or higher.

12. A polyimide resin according to any one of claims 1 to 3, wherein the mean coefficient of linear thermal expansion (CTE) in the range of 50°C to 100°C, as measured by thermomechanical analysis (TMA) in accordance with JIS K 7197:2012, is less than 49 ppm / °C.

13. The polyimide resin according to any one of claims 1 to 3, wherein the average value of the elongation at break at 23°C obtained by the following method is 5% or more. (method) Prepare a solution by dissolving 4 g of polyimide resin in 16 g of γ-butyrolactone. Spin coat the solution onto an 8-inch silicon wafer, then heat at 110°C for 3 minutes to dry the solution. Spin coating is performed so that the film thickness after drying is 10 μm. Next, heat at 170°C for 3 hours under a nitrogen atmosphere to form a cured film. Using a dicing saw, the silicon wafer with the hardened film formed on it is cut into strips 7 mm wide. The cut silicon wafer is immersed in a 2% hydrofluoric acid aqueous solution to peel off the hardened film from the silicon wafer. The peeled hardened film is dried at 80°C for 90 minutes to obtain a hardened film. A test piece (50 mm × 7 mm × 10 μm thick) is cut from the obtained hardened film. In accordance with JIS K 7197:2012, the elongation at break from the initial position to the breaking point of the test piece is measured using a thermomechanical analyzer under air atmosphere, tensile mode, chuck distance of 20 mm, tensile speed of 5 mm / min, and 23°C. Measurements are performed on 10 test pieces, and the average value of the elongation at break is calculated.

14. A varnish comprising the polyimide resin and solvent according to any one of claims 1 to 3.

15. A polyimide resin according to any one of claims 1 to 3, Polymerization initiator and A photosensitive resin composition containing [the specified element].

16. The photosensitive resin composition according to claim 15, further comprising a polyfunctional (meth)acrylate.

17. The photosensitive resin composition according to claim 16, wherein the polyfunctional (meth)acrylate comprises a (meth)acrylate with five or more functions.

18. The photosensitive resin composition according to claim 16, wherein the polyfunctional (meth)acrylate comprises a (meth)acrylate with two or more functions and four or fewer functions.

19. The photosensitive resin composition according to claim 16, wherein the content of the polyfunctional (meth)acrylate per 100 parts by mass of the polyimide resin is 20 parts by mass or more and 150 parts by mass or less.

20. The photosensitive resin composition according to claim 15, further comprising an epoxy compound.

21. The photosensitive resin composition according to claim 20, wherein the epoxy compound comprises an epoxy compound having a (meth)acryloyl group.

22. The photosensitive resin composition according to claim 15, further comprising a silane coupling agent.

23. The photosensitive resin composition according to claim 22, wherein the silane coupling agent comprises a silane coupling agent having a cyclic anhydride structure.

24. A photosensitive resin composition according to claim 15, used in semiconductor devices.

25. A cured product of the photosensitive resin composition according to claim 15.

26. A semiconductor device comprising the cured product described in claim 25.

27. Interlayer insulating film and A resin film containing the cured product described in claim 25 is provided on the interlayer insulating film, The rewiring embedded in the aforementioned resin film, The semiconductor device according to claim 26, comprising:

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