Polyamide-imide resin, resin composition, and semiconductor device

Abstract

The present application relates to a polyamide-imide resin comprising a structural unit (Ia) represented by the following formula and at least one selected from a structural unit (IIa), a structural unit (IIb) and a structural unit (IIc) represented by the following formulae. In the structural unit (Ia), each X independently represents a hydrogen atom, or a substituent selected from a halogen atom, an alkyl group having a carbon number of 1 to 9, an alkoxy group having a carbon number of 1 to 9 and a hydroxyalkyl group. In the structural unit (IIa), the structural unit (IIb) and the structural unit (IIc), each S independently represents an alkyl group having a carbon number of 1 to 3, a represents an integer of 0 to 4, b represents an integer of 0 to 3, and c represents an integer of 0 to 4.

Description

Technical Field

[0001] This embodiment relates to a polyamide-imide resin containing a cardo-structured fluorene backbone. Additionally, this embodiment relates to a resin composition comprising the above-described polyamide-imide resin, and a semiconductor device using the resin composition. Background Technology

[0002] One of the main causes of global warming is carbon dioxide (CO2) emissions from various industrial equipment. Therefore, addressing global warming requires building a low-carbon society. One method to achieve this is the application of power semiconductors in industrial equipment to reduce energy loss. Power semiconductors are also suitable for various applications, including automobiles, and their demand is increasing. Examples of automotive-grade power semiconductors include power cards, as well as TO, SOP, QFP, BGA, and CSP packages.

[0003] In recent years, especially with the electrification of automobiles (EVs), the power density of power semiconductors has increased, leading to a rise in the operating temperature (Tj) of devices. Consequently, the temperatures required for thermal cycling tests have also increased.

[0004] However, in thermal cycling tests at high temperatures (high Tj) designed for driving temperatures, existing power semiconductors sometimes experience delamination between components, such as at the interface between the resin sealant and the substrate or semiconductor element. In semiconductor devices, delamination between components can lead to malfunctions, thus significantly reducing the reliability of the semiconductor device.

[0005] To address the increasing heat transition temperature (Tj) of power semiconductor devices, various studies have been conducted on resin sealing materials that constitute the resin sealing layer. For example, efforts are being made to develop resin sealing materials with excellent heat resistance; in the case of resin sealing materials with a glass transition temperature exceeding 230°C, excellent heat resistance is exhibited even in high-temperature regions exceeding 200°C. However, on the other hand, as the resin hardens, the adhesion to components decreases, which can easily reduce the reliability of the semiconductor device. Furthermore, delamination between components sometimes occurs during the reflow soldering process during device assembly.

[0006] Therefore, from the viewpoint of improving the reliability of semiconductor devices, in order to suppress the peeling between components during high-temperature thermal cycling tests and reflow soldering processes, a method to improve the tightness between components in semiconductor devices is desired.

[0007] In contrast, a method is known to improve the adhesion between components of a semiconductor device by forming an undercoat made of a resin material between the components, thereby preventing delamination. For example, a method is being investigated to suppress delamination by providing an undercoat made of polyamide-imide resin between a metal lead frame and a sealing material (Patent Document 1).

[0008] Existing technical documents

[0009] Patent documents

[0010] Patent Document 1: Japanese Patent Application Publication No. 2013-135061 Summary of the Invention

[0011] The problem that the invention aims to solve

[0012] However, with the increasing Tj of power semiconductor devices, the conditions required for reliability testing of semiconductor devices have become more stringent, and existing resin materials are insufficient to fully meet these requirements. Therefore, from the viewpoint of providing highly reliable power semiconductors, there remains a desire to develop a resin material with excellent heat resistance, for example, that can prevent delamination between components even in high-temperature regions exceeding 250°C.

[0013] Therefore, in view of the above situation, the present invention provides a resin material with excellent heat resistance, which can improve the adhesion between components and suppress the occurrence of peeling, and is particularly suitable for use as a base coating forming material between components of a semiconductor device.

[0014] Methods for solving problems

[0015] From the perspective of improving delamination between components during thermal cycling tests in high-temperature regions, the resin material forming the undercoat preferably has a glass transition temperature (Tg) higher than the upper limit of the driving temperature (Tj) of the power semiconductor. Generally, it is known that resins soften at temperatures exceeding their Tg, resulting in reduced adhesion. Therefore, when the resin's Tg is lower than the driving temperature of the power semiconductor, the heat resistance becomes insufficient, making it difficult to ensure adhesion between components. As a result, delamination may occur, for example, between the resin sealant and the substrate or semiconductor element.

[0016] The inventors conducted repeated and in-depth studies on polyamide-imide resins and resin compositions thereof as resin materials, and found that polyamide-imide resins with a caloric structure fluorene backbone have high Tg. Furthermore, they discovered that when a base coating is formed between components such as a polyamide-imide resin having specific structural units or a resin composition containing the above-mentioned resin, for example, between a resin sealing layer and a substrate or semiconductor element, excellent adhesion between components can be obtained, thus completing the present invention.

[0017] That is, the embodiments of the present invention relate to the following. However, the present invention is not limited to the following embodiments, and various modifications can be made.

[0018] One embodiment relates to a polyamide-imide resin comprising a structural unit (Ia) represented by the following formula and at least one selected from structural units (IIa), (IIb), and (IIc) represented by the following formulas.

[0019] [Chemical Formula 1]

[0020]

[0021] [Chemical Formula 2]

[0022]

[0023] In the above formula (Ia), X independently represents a hydrogen atom or a substituent selected from halogen atoms, alkyl groups having 1 to 9 carbon atoms, alkoxy groups having 1 to 9 carbon atoms, and hydroxyalkyl groups.

[0024] In formulas (IIa), (IIb) and (IIc) above, S independently represents an alkyl group having 1 to 3 carbon atoms, a represents an integer from 0 to 4, b represents an integer from 0 to 3, and c represents an integer from 0 to 4.

[0025] The aforementioned polyamide-imide resin preferably further comprises the structural unit (IIIa) represented by the following formula.

[0026] [Chemical Formula 3]

[0027]

[0028] In formula (IIIa) above, R independently represents a hydrogen atom, or a substituent selected from alkyl groups having 1 to 9 carbon atoms, alkoxy groups having 1 to 9 carbon atoms, and halogen atoms, and n represents an integer from 1 to 6.

[0029] The preferred linear expansion coefficient of the above-mentioned polyamide-imide resin is 40ppm / ℃ to 70ppm / ℃.

[0030] In the above-mentioned polyamide-imide resin, based on the total amount of the above-mentioned structural unit (Ia) and at least one selected from the above-mentioned structural unit (IIa), structural unit (IIb) and structural unit (IIc), the proportion of the above-mentioned structural unit (Ia) is 20 mol% or more.

[0031] The aforementioned polyamide-imide resin preferably has a glass transition temperature of 250°C or higher. More preferably, the aforementioned polyamide-imide resin has a glass transition temperature of 300°C or higher.

[0032] Another embodiment relates to a polyamide-imide resin composition comprising the polyamide-imide resin of the above embodiments and a solvent. Preferably, the above polyamide-imide resin composition further comprises a coupling agent.

[0033] Another embodiment relates to a semiconductor device comprising a substrate and a film formed using the polyamide-imide resin composition of the above embodiment. Preferably, the semiconductor device further comprises a resin sealing layer.

[0034] The disclosure of this application relates to the subject matter described in Japanese Patent Application No. 2021-34526, filed on March 4, 2021, the disclosure of which is incorporated herein by reference.

[0035] Invention Effects

[0036] According to the present invention, a resin material with excellent heat resistance, which can improve the adhesion between components and suppress the occurrence of delamination at high temperatures, can be suitable for use as an undercoating material between components in semiconductor devices. Attached Figure Description

[0037] Figure 1 This is a schematic cross-sectional view showing an example of a semiconductor device as an implementation. Detailed Implementation

[0038] The preferred embodiments of the present invention will now be described in detail. However, the present invention is not limited to these embodiments.

[0039] <Polyamide-imide resin>

[0040] In one embodiment, the polyamide-imide resin comprises the structural unit (Ia) described later and at least one selected from structural units (IIa), (IIb), and (IIc). Details of each structural unit are described below.

[0041] The structural unit (Ia) is represented by the following formula.

[0042] [Chemical Formula 4]

[0043]

[0044] In the above structural unit (Ia), X can be the same or different from each other. Each X independently represents a hydrogen atom or a substituent selected from halogen atoms, alkyl groups having 1 to 9 carbon atoms, alkoxy groups having 1 to 9 carbon atoms, and hydroxyalkyl groups. The halogen atom can be a fluorine atom, a chlorine atom, or a bromine atom. The alkyl group and the alkoxy group can be any of a straight-chain structure, a branched structure, and a cyclic structure.

[0045] In one embodiment, X is preferably a hydrogen atom, an alkyl group having 1 to 9 carbon atoms, or a halogen atom. The alkyl group is more preferably an alkyl group having 1 to 6 carbon atoms, and even more preferably an alkyl group having 1 to 3 carbon atoms. In one embodiment, X is preferably a hydrogen atom.

[0046] Structural unit (IIa), structural unit (IIb), and structural unit (IIc) are represented by the following formulas.

[0047] [Chemical Formula 5]

[0048]

[0049] In the above structural units (IIa), (IIb) and (IIc), S independently represents an alkyl group having 1 to 3 carbon atoms, a represents an integer from 0 to 4, b represents an integer from 0 to 3, and c represents an integer from 0 to 4.

[0050] The aforementioned alkyl group can be either a straight-chain structure or a branched structure, preferably a straight-chain structure. More preferably, the alkyl group has 1 or 2 carbon atoms. When the alkyl group is a straight-chain structure, especially when it is an alkyl group with 1 or 2 carbon atoms, there is a tendency to easily obtain a resin with a rigid structure. By using a resin with a rigid structure to form a film, there is a tendency to easily suppress the coefficient of linear expansion (CTE). By suppressing the CTE of the film to a low level, for example in the operating environment of a semiconductor device, it is easy to minimize the difference in CTE between the film and other components. As a result, for example in a semiconductor device, there is a tendency to reduce thermal stress and easily improve the reliability of the semiconductor device.

[0051] In one embodiment, the structural units (IIa), (IIb), or (IIc) described above can be derived using diamine compounds or diisocyanate compounds having corresponding structures. While not particularly limited, the following compounds are specific examples of diamine compounds capable of deriving the structural units (IIa), (IIb), and (IIc). The amino groups shown in the following compounds can also be replaced with isocyanate groups.

[0052] [Chemical Formula 6]

[0053]

[0054] [Chemical Formula 7]

[0055]

[0056] [Chemical Formula 8]

[0057]

[0058] In one embodiment, 'a' in structural unit (IIa) is preferably 0 to 3, more preferably 0 to 2, further preferably 0 or 1, and most preferably 0. 'b' in structural unit (IIb) is preferably 0 to 2, more preferably 0 or 1, and most preferably 0. 'c' in structural unit (IIc) is preferably 0 to 3, more preferably 0 to 2, further preferably 0 or 1, and most preferably 0.

[0059] When the number of substituents in the aforementioned structural units (IIa), (IIb), or (IIc) is less, especially when they are unsubstituted (i.e., when a, b, or c is 0), there is a tendency to easily obtain resins with rigid structures. By using a resin with a rigid structure to form a film, there is a tendency to easily suppress the coefficient of linear expansion (CTE). By suppressing the CTE of the film to a low level, for example in the operating environment of a semiconductor device, it is easy to minimize the difference in CTE with other components. As a result, for example in a semiconductor device, there is a tendency to reduce thermal stress and easily improve the reliability of the semiconductor device.

[0060] In view of the above, in one embodiment, the polyamide-imide resin preferably comprises the above-described structural unit (Ia), and at least one selected from the structural units (IIa-1), (IIb-1), and (IIc-1) represented by the following formulas. While not particularly limited, a structure in which two bonding sites (indicated by "*") of other structural parts are in a para-position relationship is more preferred.

[0061] [Chemical Formula 9]

[0062]

[0063] Polyamide-imide resins are resins having amide and imide bonds within their molecular backbone, obtained, for example, by reacting a diamine or diisocyanate component with an acid such as a tricarboxylic anhydride. In this view, in one embodiment, a polyamide-imide resin comprising the aforementioned structural unit (Ia) and at least one selected from the aforementioned structural units (IIa), (IIb), and (IIc) can be derived using a compound represented by formula (I), and at least one compound represented by formulas (IIA), (IIB), and (IIC). Structural units (Ia), (IIa), (IIb), and (IIc) respectively correspond to residues obtained by removing the substituent Y (amino or isocyanate group) from the compounds represented by formulas (I), (IIA), (IIB), and (IIC), and can be directly bonded to amide or imide bond sites in the resin structure.

[0064] [Chemical Formula 10]

[0065]

[0066] In formula (I) above, Y is an amino group (-NH2) or an isocyanate group (-NCO). Additionally, X is as previously described in item (Ia).

[0067] [Chemical Formula 11]

[0068]

[0069] In formulas (IIA), (IIB), and (IIC) above, Y is an amino group (-NH2) or an isocyanate group (-NCO). Additionally, S, a, b, and c are as previously described.

[0070] Specific examples of compounds represented by formula (I) above include 9,9-bis(4-aminophenyl)fluorene, 9,9-bis(4-amino-3-methylphenyl)fluorene, 9,9-bis(4-amino-3-chlorophenyl)fluorene, and 9,9-bis(4-amino-3-fluorophenyl)fluorene. They are suitable as diamine compounds capable of deriving structural unit (Ia).

[0071] Specific examples of compounds represented by the above formula (IIA) include 4,4'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, and 3,3'-diaminodiphenylmethane. They are suitable as diamine compounds capable of deriving the structural unit (IIa-1).

[0072] Specific examples of compounds represented by the above formula (IIB) include 1,5-naphthyldiamine and 1,8-naphthyldiamine. They can be suitably used as diamine compounds capable of deriving the structural unit (IIb-1).

[0073] Specific examples of compounds represented by the above formula (IIC) include 1,3-phenylenediamine and 1,4-phenylenediamine. They can be suitably used as diamine compounds capable of deriving the structural unit (IIc-1).

[0074] For example, from the viewpoint of suppressing delamination between components at the drive temperature (Tj) or reflow soldering temperature of power semiconductors, polyamide-imide resins preferably have a glass transition temperature higher than the upper limit of Tj or reflow soldering temperature. In this specification, "glass transition temperature (Tg)" refers to the value obtained using a thermomechanical analysis apparatus after coating and heating a film obtained from a resin dissolved in a solvent.

[0075] In one embodiment, a thermal cycling test to increase the driving temperature (high Tg) of the power semiconductor is envisioned to be performed at a temperature of 175°C or higher. Furthermore, during semiconductor mounting and reflow soldering, the test is performed at a high temperature of approximately 260°C. Therefore, in one embodiment, the Tg of the polyamide-imide resin is preferably 250°C or higher. More preferably, the Tg of the polyamide-imide resin is 270°C or higher, even more preferably 290°C or higher, and still more preferably 300°C or higher.

[0076] During the reflow soldering process in device installation, peeling between components occurs due to stress caused by the rapid vaporization of moisture contained in the device and stress caused by the difference in linear expansion between components, which exceeds the adhesion force between components. In one embodiment, from the viewpoint of suppressing peeling during the reflow soldering process, the Tg of the aforementioned polyamide-imide resin is preferably 300°C or higher, more preferably 320°C or higher.

[0077] According to the polyamide-imide resin of the above embodiments, a temperature resistance (Tg) of 250°C or higher can be easily obtained. In the polyamide-imide resin of the above embodiments, it is believed that the presence of a skeleton known as a caloric structure in the structural unit (Ia) contributes to the increase in Tg. Furthermore, it is speculated that the presence of structural units (IIa), (IIb), and (IIc) in the resin can further increase the Tg. In addition, when using polyamide-imide resin to form a film, there is a tendency to easily adjust the film's physical properties such as CTE, elastic modulus, and adhesion to the adherend. For example, by adjusting the ratio of structural unit (Ia) to structural units (IIa), (IIb), and (IIc), the desired film physical properties such as Tg, CTE, elastic modulus, and adhesion can be easily obtained. As a result, when using the polyamide-imide resin of the above embodiments as a constituent material of a semiconductor device, the reliability of the semiconductor device can be easily improved.

[0078] Generally, films made of resins with high Tg tend to have reduced flexibility. When film flexibility is low, it cannot mitigate stress generated within the semiconductor device and is prone to peeling. From this perspective, in one embodiment, the polyamide-imide resin preferably includes the structural unit (IIIa) represented by the following formula. It can be considered that the polyamide-imide resin of the above embodiment, also having structural unit (IIIa), can easily yield a film with improved flexibility and excellent suppleness.

[0079] [Chemical Formula 12]

[0080]

[0081] In structural unit (IIIa), each R independently represents a hydrogen atom, or a substituent selected from alkyl groups having 1 to 9 carbon atoms, alkoxy groups having 1 to 9 carbon atoms, and halogen atoms. The halogen atom can be a fluorine atom, a chlorine atom, or a bromine atom. The alkyl group and the alkoxy group can be any of a straight-chain structure, a branched structure, or a cyclic structure.

[0082] In one embodiment, R is preferably an alkyl group having 1 to 9 carbon atoms, more preferably an alkyl group having 1 to 6 carbon atoms, and even more preferably an alkyl group having 1 to 3 carbon atoms.

[0083] n represents an integer from 1 to 6. n is preferably an integer from 2 to 4, and more preferably 3 or 4.

[0084] In one embodiment, the above-described structural unit (IIIa) can be derived using a compound represented by formula (III). Structural unit (IIIa) is equivalent to the residue after removing the substituent Y (amino or isocyanate group) from the compound shown by formula (III), and can be directly bonded to an amide bond site or an imide bond site in the structure of the resin.

[0085] [Chemical Formula 13]

[0086]

[0087] In formula (III) above, Y is an amino (-NH2) or isocyanate group (-NCO), and R and n are as previously described.

[0088] Specific examples of compounds represented by formula (III) above include: 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane, 1,3-bis(2-aminoethyl)-1,1,3,3-tetramethyldisiloxane, 1,3-bis(aminomethyl)-1,1,3,3-tetramethyldisiloxane, 1,3-bis(4-aminobutyl)-1,1,3,3-tetramethyldisiloxane, 1,3-bis(5-aminopentyl)-1,1,3,3-tetramethyldisiloxane, 1,3-bis(6-aminohexyl)-1,1,3,3-tetramethyldisiloxane, etc.

[0089] As described above, the polyamide-imide resin of the above embodiments can be considered to have a structural unit (IIIa) in combination with structural unit (Ia) and at least one selected from structural unit (IIa), structural unit (IIb), and structural unit (IIc), thereby easily balancing a high glass transition temperature (Tg) and resin flexibility. Therefore, for example, when the undercoating layer provided between the components of a semiconductor device contains the polyamide-imide resin of the above embodiments, excellent adhesion can be easily obtained even in tests conducted in high-temperature regions above 250°C.

[0090] Furthermore, when the constituent material of the power semiconductor device includes the polyamide-imide resin of the above embodiment, it is possible to suppress the softening of the resin and the reduction of its adhesiveness due to heat generated during operation. Therefore, high reliability can be obtained in power semiconductor devices using the polyamide-imide resin of the above embodiment.

[0091] In polyamide-imide resins, the proportion of structural units (Ia) relative to the total amount of structural units derived from diamine and / or diisocyanate components can be 10 mol% or more, 15 mol% or more, 18 mol% or more, 30 mol% or more, 40 mol% or more, 45 mol% or more, 55 mol% or more, 65 mol% or more, or 70 mol% or more. The proportion of the aforementioned structural units (Ia) can be 95 mol% or less, 90 mol% or less, 85 mol% or less, 80 mol% or less, or 75 mol% or less.

[0092] In one embodiment, the proportion of the above-mentioned structural unit (Ia) may be 10 mol% to 95 mol%, preferably 15 mol% to 95 mol%, more preferably 45 mol% to 90 mol%, further preferably 55 mol% to 85 mol%, and even more preferably 65 mol% to 80 mol%.

[0093] In one embodiment, the total proportion of structural unit (Ia) as a structural unit derived from diamine and / or diisocyanate components, and the proportion of at least one selected from structural units (IIa), (IIb), and (IIc), may be 70 mol% or more, 80 mol% or more, 85 mol% or more, 90 mol% or more, or 100 mol%. In one embodiment, the total proportion may be 95 mol% or less.

[0094] In one embodiment, based on the total amount of the above-described structural unit (Ia) and at least one selected from the above-described structural units (IIa), (IIb), and (IIc), the proportion of the above-described structural unit (Ia) may be 20 mol% or more. The above-described proportion of the above-described structural unit (Ia) is preferably 45 mol% or more, more preferably 50 mol% or more, further preferably 80 mol% or more, and even more preferably 85 mol% or more.

[0095] On the other hand, relative to the total amount of structural units derived from diamine and / or diisocyanate components, the proportion of at least one selected from structural unit (IIa), structural unit (IIb), and structural unit (IIc) is preferably 10 mol% or more. In one embodiment, the above proportion is preferably 10 mol% to 80 mol%, more preferably 12 mol% to 65 mol%, and even more preferably 15 mol% to 50 mol%. It should be noted that the above proportion, when the polyamide-imide resin contains two or more of structural units (IIa), structural unit (IIb), and structural unit (IIc), refers to their total proportion.

[0096] In polyamide-imide resins, based on the total amount of all structural units constituting the resin, the sum of the proportion of the aforementioned structural unit (Ia) and the proportion of at least one selected from (IIa), (IIb), and (IIc) is preferably 35 mol% or more, more preferably 40 mol% or more, and even more preferably 45 mol% or more. Here, the proportion (mol%) of each structural unit can be calculated based on the number of moles of the monomer compound corresponding to each structural unit.

[0097] In another embodiment, the polyamide-imide resin preferably further comprises structural unit (IIIa). In one embodiment, the proportion of structural unit (IIIa) may be less than 20 mol%, less than 15 mol%, or less than 10 mol% relative to the total amount of structural units derived from the diamine component and / or diisocyanate component. The proportion of the above-mentioned structural unit (IIIa) may be more than 2.5 mol%, more than 5.0 mol%, or more than 7.5 mol%.

[0098] In the above embodiments, the total proportion of structural unit (Ia), the proportion of at least one selected from structural unit (IIa), structural unit (IIb), and structural unit (IIc), and the proportion of structural unit (IIIa) as structural units derived from diamine and / or diisocyanate components can be 75 mol% or more, 80 mol% or more, 85 mol% or more, 90 mol% or more, 95 mol% or more, or 100 mol%.

[0099] In the above embodiments, the proportion of the structural unit (IIIa) is preferably 2.5 mol% to 20 mol%, more preferably 5 mol% to 15 mol%, and even more preferably 7.5 mol% to 10 mol%. By adjusting the proportion of the structural unit (IIIa) to the above range, the characteristics produced by the structural unit (Ia) and at least one of the structural units (IIa), (IIb), and (IIc) can be easily exhibited.

[0100] In another embodiment, the polyamide-imide resin may also include additional structural units other than those structural units, in addition to the above-described structural unit (Ia), at least one selected from the above-described structural unit (IIa), structural unit (IIb) and structural unit (IIc), and the above-described structural unit (IIIa) as needed.

[0101] The additional structural unit may be a structural unit derived from an aromatic diamine or aromatic diisocyanate, an aliphatic diamine or aliphatic diisocyanate, or an alicyclic diamine or alicyclic diisocyanate, having a structure different from that of the aforementioned structural units (Ia), (IIa), (IIb), (IIc), and (IIIa). The proportion of such an additional structural unit relative to the total amount of structural units derived from diamine and / or diisocyanate components is preferably 20 mol% or less. More preferably, the proportion of the aforementioned additional structural unit is 10 mol% or less, and even more preferably 5 mol% or less.

[0102] As an example of aromatic diamines (diisocyanates) capable of deriving additional structural units, the following can be cited:

[0103] 2,7-diaminofluorene,

[0104] 9,9-Bis[4-(4-aminophenoxy)phenyl]-9H-fluorene,

[0105] 2,2'-Di-trifluoromethyl-4,4'-diaminobiphenyl,

[0106] 4,4'-Diaminodiphenyl sulfone,

[0107] 3,3'-Diaminodiphenyl sulfone,

[0108] 4,4'-Diamino-2,2'-Biphenyldisulfonic acid,

[0109] 3,4'-Diaminodiphenyl ether,

[0110] bis[4-(4-aminophenoxy)phenyl]sulfone,

[0111] bis[4-(3-aminophenoxy)phenyl]sulfone,

[0112] 2,2-bis[4-(4-aminophenoxy)phenyl]propane,

[0113] 1,4-bis(4-aminophenoxy)benzene,

[0114] 1,3-bis(3-aminophenoxy)benzene,

[0115] 2,2-Bis(4-aminophenyl)hexafluoropropane,

[0116] 1,4-Phenylenediamine,

[0117] 2-Chloro-1,4-phenylenediamine,

[0118] 1,3-phenylenediamine,

[0119] 4,4'-Diaminobenzophenone

[0120] 3,3'-Diaminobenzophenone,

[0121] 3,4'-Diaminodiphenylmethane,

[0122] 4,4'-Diaminobenzoylaniline,

[0123] 3,6-Diaminocarbazole,

[0124] 4,4'-bis(4-aminophenoxy)biphenyl,

[0125] 2-Trifluoromethyl-1,4-diaminobenzene,

[0126] 2,2-Bis[4-(4-aminophenoxy)phenyl]hexafluoropropane,

[0127] 2,2-Bis(4-aminophenyl)hexafluoropropane,

[0128] 2,2'-Bis(trifluoromethyl)benzidine,

[0129] 2,2'-Di-trifluoromethyl-4,4'-diaminodiphenyl ether,

[0130] 4-Aminophenyl sulfide,

[0131] 4,4'-Diamino-3,3'-Dimethylbiphenyl,

[0132] Naphthyldiamine,

[0133] Naphthalene diisocyanate.

[0134] As an example of an aliphatic diamine (diisocyanate) capable of deriving additional structural units, the following can be cited:

[0135] 1,4-Cyclohexanediamine,

[0136] 1,3-Cyclohexanediamine,

[0137] 1,4-Di(aminomethyl)cyclohexane,

[0138] 1,3-bis(aminomethyl)cyclohexane,

[0139] Bis(aminomethyl)norbornene,

[0140] 4,4'-Methylenebis(cyclohexylamine),

[0141] Hexamethylenediamine

[0142] Hexamethylene diisocyanate.

[0143] In one embodiment, when a diamine is used in the manufacture of the polyamide-imide resin, an anhydride of an aliphatic or aromatic tricarboxylic acid can be used. From the viewpoint of heat resistance, an anhydride of an aromatic tricarboxylic acid is preferred. In one embodiment, for example, as the acid component, an acyl halide of trimellitic anhydride is preferred. Among these, trimellitic anhydride chloride represented by formula (IV) is particularly preferred.

[0144] [Chemical Formula 14]

[0145]

[0146] In view of the above, in one embodiment, the polyamide-imide resin preferably comprises a structural unit represented by the following formula (IVa), which can be derived from the reaction of a trimellitic anhydride acyl halide with a diamine component.

[0147] [Chemical Formula 15]

[0148]

[0149] In one embodiment, based on the total amount of structural units derived from the acid component, the proportion of structural units derived from formula (IV) above is preferably 50 mol% or more, more preferably 75 mol% or more, and even more preferably 90 mol% or more. That is, in one embodiment, based on the total mass of the acid component, the content of trimellitic anhydride acyl halide is preferably 50% by mass or more, more preferably 75% by mass or more, and even more preferably 90% by mass or more.

[0150] In one embodiment, the proportion of structural units derived from formula (IV) above may be 100 mol% relative to the total amount of acid components. That is, in one embodiment, the content of trimellitic anhydride acyl halide may be 100 mol% based on the total mass of acid components.

[0151] In one embodiment, the polyamide-imide resin may be a resin obtained by using a compound represented by formula (I) above and a compound selected from at least one of formulas (IIA), (IIB), and (IIC) above as a diamine component or a diisocyanate component, and using a compound represented by formula (IV) above as an acid component. In another embodiment, it may also be a resin obtained by further adding a compound represented by formula (III) as a diamine component or a diisocyanate component. In another embodiment, the polyamide-imide resin may also be a resin obtained by using an acid component other than the compound represented by formula (IV) above as an acid component.

[0152] The acid components that can be used may include, for example, the tricarboxylic anhydrides or their acyl halides other than those represented by formula (IV) above, and tricarboxylic acids such as trimellitic acid. Additionally, as acid components, tetracarboxylic anhydrides such as pyromellitic dianhydride and biphenyltetracarboxylic dianhydride, aromatic dicarboxylic acids such as terephthalic acid and isophthalic acid, alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid, and aliphatic dicarboxylic acids such as adipic acid and sebacic acid may be used.

[0153] The weight-average molecular weight (Mw) of the polyamide-imide resin is preferably in the range of 30,000 to 120,000. Polyamide-imide resins with Mw within this range readily form coatings of the preferred film thickness described later during coating operations. More preferably, the Mw of the polyamide-imide resin is in the range of 35,000 to 110,000, and even more preferably, in the range of 38,000 to 100,000. The term "Mw" as used in this specification is a value determined using gel permeation chromatography and converted to standard polystyrene.

[0154] From the viewpoint of workability during film formation, the aforementioned polyamide-imide resin is preferably soluble in an organic solvent at room temperature. In this specification, "soluble in an organic solvent at room temperature" means that when an organic solvent is added to the resin at room temperature and stirred, the resulting solution, visually confirmed, is free of precipitates, turbidity, and is entirely transparent. Here, "room temperature" can be approximately in the range of 10°C to 40°C, preferably in the range of 20°C to 30°C. In one embodiment, the aforementioned "solution" refers, for example, to a solution obtained by adding 1g to 30g of the resin powder to 100mL of organic solvent. The organic solvent will be described later.

[0155] (Manufacturing method of polyamide-imide resin)

[0156] Polyamide-imide resins can be manufactured using known methods, and there are no particular limitations. For example, polyamide-imide resins can be manufactured by reacting a diamine component and / or a diisocyanate component with an acid component. The diamine component, diisocyanate component, and acid component are as previously described. The above reaction can be carried out under solvent-free conditions or in the presence of an organic solvent. The reaction temperature is preferably in the range of 25°C to 250°C. The reaction time can be appropriately adjusted according to the batch size, the reaction conditions used, etc.

[0157] There are no particular restrictions on the organic solvents (reaction solvents) used in the manufacture of polyamide-imide resins. Examples of usable organic solvents include: ether-based solvents such as diethylene glycol dimethyl ether, diethylene glycol diethyl ether, triethylene glycol dimethyl ether, and triethylene glycol diethyl ether; sulfur-based solvents such as dimethyl sulfoxide, diethyl sulfoxide, dimethyl sulfone, and sulfolane; cyclic ester-based (lactone-based) solvents such as γ-butyrolactone; non-cyclic ester-based solvents such as acetic acid cellosol; ketone-based solvents such as cyclohexanone and methyl ethyl ketone; nitrogen-based solvents such as N-methyl-2-pyrrolidone, dimethylacetamide, and 1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone; and aromatic hydrocarbon-based solvents such as toluene and xylene. One of these organic solvents may be used alone, or two or more may be used in combination.

[0158] In one embodiment, an organic solvent capable of dissolving the generated resin is preferably used, and a polar solvent is preferred. Polar solvents will be described later; for example, nitrogen-containing solvents are preferred.

[0159] In one embodiment, the polyamide-imide resin can be manufactured by reacting an acidic component with a diamine component to produce a polyamide-imide resin precursor, and then dehydrating and ring-closing the precursor to obtain the polyamide-imide resin. However, the ring-opening method for the precursor is not particularly limited, and methods well-known in the art can be used. For example, a thermal ring-closing method can be used, where dehydration and ring closure are achieved by heating under normal or reduced pressure; or a chemical ring-closing method can be used, with or without a catalyst, using a dehydrating agent such as acetic anhydride.

[0160] In the case of the thermal closed-loop method, it is preferable to remove the water generated in the dehydration reaction from the system simultaneously. During the dehydration reaction, the reaction solution can be heated to 80°C to 400°C, preferably 100°C to 250°C. Alternatively, the water can be removed by azeotropic reaction using an organic solvent such as benzene, toluene, or xylene that can react with water.

[0161] In the case of the chemical cyclization method, the reaction can be carried out in the presence of a chemical dehydrating agent at a temperature of 0°C to 120°C, preferably 10°C to 80°C. As a chemical dehydrating agent, anhydrides such as acetic anhydride, propionic anhydride, butyric anhydride, and benzoic anhydride are preferred; as are carbodiimide compounds such as dicyclohexylcarbodiimide. Substances that promote the cyclization reaction of pyridine, isoquinoline, trimethylamine, triethylamine, aminopyridine, imidazole, etc., are also preferred.

[0162] Relative to the total amount of diamine, chemical dehydrating agents can be used at a ratio of 90 mol% to 600 mol%, while substances that promote cyclization reactions can be used at a ratio of 40 mol% to 300 mol%, relative to the total amount of diamine. Additionally, dehydration catalysts such as triphenyl phosphite, tricyclohexyl phosphite, triphenyl phosphate, phosphoric acid, phosphorus pentoxide, and other phosphorus compounds; and boron compounds such as boric acid and boric anhydride can also be used.

[0163] In the manufacture of polyamide-imide resin, the molar ratio of the acid component to the diamine component (diisocyanate component) is not particularly limited and can be adjusted to allow the reaction to proceed without excess or deficiency. In one embodiment, from the viewpoint of the molecular weight and degree of crosslinking of the resulting polyamide-imide resin, the total amount of the diamine component is preferably set to 0.90 mol to 1.10 mol relative to the total amount of acid component (1.00 mol), more preferably 0.95 mol to 1.05 mol, and even more preferably 0.97 mol to 1.03 mol.

[0164] <Polyamide-imide resin composition>

[0165] In one embodiment, the polyamide-imide resin composition (hereinafter, sometimes simply referred to as the resin composition) comprises the polyamide-imide resin of the above embodiments and a solvent. In this specification, the resin composition is sometimes also referred to as a varnish.

[0166] (solvent)

[0167] The solvent can be any solvent capable of dissolving polyamide-imide resin, and there are no particular limitations. A "solvent capable of dissolving polyamide-imide resin" refers to a solvent in which, under conditions where the solvent temperature is not particularly limited, polyamide-imide resin powder is added to the solvent and stirred; when the resulting solution is visually observed, no precipitation or turbidity is observed, and the solution becomes completely transparent. In one embodiment, the solvent constituting the resin composition may be the same as the reaction solvent used in manufacturing the resin. Polar solvents are particularly preferred.

[0168] Examples of polar solvents include: nitrogen-containing compounds such as N-methylpyrrolidone, dimethylacetamide, dimethylformamide, and 1,3-dimethyltetrahydro-2(1H)-pyrimidinone; sulfur-containing compounds such as sulfolane and dimethyl sulfoxide; lactones such as γ-butyrolactone, γ-valerolactone, γ-caprolactone, γ-heptylactone, α-acetyl-γ-butyrolactone, and ε-caprolactone; ketones such as methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, and acetophenone; non-cyclic esters such as acetic acid cellosol; ethylene glycol; glycerol; and ethers including diethylene glycol dimethyl ether, diethylene glycol dimethyl ether, diethylene glycol dimethyl ether, dimethyl sulfoxide ... Diethylene glycol dialkyl ethers such as diethylene glycol diethyl ether, diethylene glycol dipropyl ether, and diethylene glycol dibutyl ether; triethylene glycol dialkyl ethers such as triethylene glycol dimethyl ether, triethylene glycol diethyl ether, triethylene glycol dipropyl ether, and triethylene glycol dibutyl ether; tetraethylene glycol dialkyl ethers such as tetraethylene glycol dimethyl ether, tetraethylene glycol diethyl ether, tetraethylene glycol dipropyl ether, and tetraethylene glycol dibutyl ether; diethylene glycol monomethyl ether and diethylene glycol monoethyl ether; triethylene glycol monoalkyl ethers such as triethylene glycol monomethyl ether and triethylene glycol monoethyl ether; and tetraethylene glycol monoalkyl ethers such as tetraethylene glycol monomethyl ether and tetraethylene glycol monoethyl ether.

[0169] In one embodiment, the solvent is preferably selected from at least one of diethylene glycol dimethyl ether, triethylene glycol, triethylene glycol dimethyl ether, N-methyl-2-pyrrolidone, γ-butyrolactone, γ-valerolactone, δ-valerolactone, γ-caprolactone, ε-caprolactone, α-methyl-γ-butyrolactone, ethyl cellosolve, ethyl cellosolve acetate, butyl cellosolve, butyl cellosolve acetate, cyclopentanone, cyclohexanone, tetrahydrofuran, 1,4-dioxane, dibutyl ether, dimethyl sulfoxide, 1,3-dimethyl-2-imidazolinone, dimethylacetamide, N,N-dimethylformamide, ethylene carbonate, propylene carbonate, and propylene glycol methyl acetate. When two or more solvents are used in combination, they can be mixed in any proportion.

[0170] Of the solvents mentioned above, from the viewpoint of film-forming properties, solvents with relatively low boiling points are preferred. For example, diethylene glycol dimethyl ether, triethylene glycol, and triethylene glycol dimethyl ether can be suitably used.

[0171] The amount of solvent in the above resin composition can be appropriately adjusted considering viscosity. While not particularly limited, in one embodiment, the amount of solvent is preferably in a ratio of 500 to 3,500 parts by mass relative to 100 parts by mass of the total resin in the above resin composition. More preferably, the solvent is in a ratio of 500 to 2,000 parts by mass relative to 100 parts by mass of the total resin.

[0172] (additive)

[0173] For the above-mentioned polyamide-imide resin composition (varnish), additives such as colorants and coupling agents, as well as additional components such as resin modifiers, may be added as needed. When the polyamide-imide resin composition contains additional components, the amount of the additional component is preferably 50 parts by weight or less, relative to 100 parts by weight of the total amount of polyamide-imide resin (solid component) in the polyamide-imide resin composition. By setting the amount of the above-mentioned additional component to 50 parts by weight or less, it is easier to suppress the reduction of the physical properties of the obtained coating film.

[0174] In one embodiment, the polyamide-imide resin composition may also include a coupling agent. Examples of possible additional components are given below.

[0175] (Coupled agent)

[0176] There are no particular limitations on the coupling agents that can be used; they can be any of the silane-based, titanium-based, and aluminum-based systems, but silane-based coupling agents are most preferred. As for silane-based coupling agents, there are no particular limitations; examples include: vinyltrichlorosilane, vinyltris(β-methoxyethoxy)silane, vinyltriethoxysilane, vinyltrimethoxysilane, γ-methacryloyloxypropyltrimethoxysilane, γ-methacryloyloxypropylmethyldimethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, and N-β-(aminoethyl)γ-aminopropyltrimethoxysilane. N-β(aminoethyl)γ-aminopropylmethyldimethoxysilane, γ-aminopropyltriethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, 3-aminopropylmethyldiethoxysilane, 3-ureopropyltriethoxysilane, 3-ureopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyl-tris[2-(2-methoxyethoxy)ethoxy]silane, N-methyl-3-aminopropyltrimethoxysilane, triaminopropyl-trimethoxysilane, 3-4,5-dihydroimidazolium Azoxyl-1-ylpropyltrimethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-chloropropylmethyldimethoxysilane, 3-chloropropyldimethoxysilane, 3-cyanopropyltriethoxysilane, hexamethyldisilazane, N,O-bis(trimethylsilyl)acetamide, methyltrimethoxysilane, methyltriethoxysilane, ethyltrichlorosilane, n-propyltrimethoxysilane, isobutyltrimethoxysilane, pentyltrichlorosilane, octyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, methyltri(methylpropyl) (Oenyloxyethoxy)silane, methyltris(glycidyloxy)silane, N-β(N-vinylbenzylaminoethyl)-γ-aminopropyltrimethoxysilane, octadecyldimethyl[3-(trimethoxysilyl)propyl]ammonium chloride, γ-chloropropylmethyldichlorosilane, γ-chloropropylmethyldimethoxysilane, γ-chloropropylmethyldiethoxysilane, trimethylsilyl isocyanate, dimethylsilyl isocyanate, methylsilyl triisocyanate, vinylsilyl triisocyanate, phenylsilyl triisocyanate, tetraisocyanate silane, ethoxysilane isocyanate, etc. One of these can be used alone, or two or more can be used in combination.

[0177] There are no particular limitations on its use as a titanium-based coupling agent. Examples include: isopropyl trioctyl titanate, isopropyl dimethacrylate isostearyl titanate, isopropyl tri-dodecylbenzenesulfonyl titanate, isopropyl isostearyl diacrylate titanate, isopropyl tris(dioctyl phosphate) titanate, isopropyl tricumylphenyl titanate, isopropyl tris(dioctyl pyrophosphate) titanate, isopropyl tris(n-aminoethyl) titanate, tetraisopropyl bis(dioctyl phosphite) titanate, tetraoctyl bis(di-tetrazyl phosphite) titanate, tetra(2,2-diallyloxymethyl-1-butyl)bis(di-tetrazyl) phosphite titanate, dicumylphenyloxyacetate titanate, bis(dioctyl pyrophosphate) titanate, and bis(dioctyl pyrophosphate) titanate. Phosphate ester (P-O-acetate) titanate, tetraisopropyl titanate, tetra-n-butyl titanate, butyl titanate dimer, tetra(2-ethylhexyl) titanate, acetylacetone titanium, polyacetylacetone titanium, octyl glycol titanium, titanium ammonium lactate, titanium lactate, titanium ethyl lactate, triethanolamine titanium, polyhydroxystearate titanium, tetramethyl orthotitanate, tetraethyl orthotitanate, tetrapropyl orthotitanate, tetraisobutyl orthotitanate, stearyl titanate, toluene titanate monomer, toluene titanate polymer, diisopropoxy-bis(2,4-pentanedione)titanium(IV), diisopropyl-bis-triethanolamine titanate, octyl glycol titanate, tetra-n-butoxytitanate polymer, tri-n-butoxytitanate monostearate polymer, tri-n-butoxytitanate monostearate, etc. One of these can be used alone, or two or more can be used in combination.

[0178] There are no particular limitations on aluminum-based coupling agents. Examples include: aluminum diisopropoxide, aluminum tri(ethyl acetoacetate), aluminum alkyl acetoacetate diisopropoxide, aluminum monoacetoacetate bis(ethyl acetoacetate), aluminum tri(acetylacetone), aluminum-monoisopropoxymonooleoethyl acetoacetate, aluminum-di-n-butoxymonoethyl acetoacetate, aluminum-diisopropoxymonoethyl acetoacetate, etc.; aluminum alkoxides such as aluminum isopropoxide, aluminum mono-sec-butoxydiisopropoxide, aluminum sec-butoxide, and aluminum ethoxide. One of these can be used alone, or two or more can be used in combination.

[0179] In one embodiment, the viscosity of the polyamide-imide resin composition is preferably in the range of 10 mPa·s to 400 mPa·s, more preferably in the range of 10 mPa·s to 300 mPa·s. Here, the above viscosity is a value obtained using an E-type viscometer at 25°C and 10 rpm for a varnish prepared by dissolving the non-volatile component (solid component) in a solvent in a manner where the non-volatile component (solid component) is 1% to 20% by mass. If the viscosity measured at 10 rpm is 10 mPa·s or higher, sufficient film thickness can be easily ensured during coating. Furthermore, if the above viscosity is 400 mPa·s or lower, uniform film thickness can be easily ensured during coating. Therefore, by adjusting the viscosity to the above range, excellent printability can be easily obtained.

[0180] In one embodiment, from the viewpoint of obtaining excellent coatability, the viscosity is preferably greater than 50 mPa·s, more preferably greater than 100 mPa·s. If the viscosity is too low, the wetting spread sometimes exceeds the specified range, making it difficult to handle.

[0181] It should be noted that the above viscosity can be measured, for example, using a viscometer (RE type) manufactured by Toki Sangyo Co., Ltd. The viscosity is measured as follows: During measurement, the measurement temperature is set to 25℃±0.5℃, then 1mL to 1.5mL of the resin composition (varnish) is added to the viscometer, and the viscosity is recorded 10 minutes after the start of the measurement.

[0182] In one embodiment, the film thickness when forming the resin composition is not particularly limited and can be in the range of 0.5 μm to 50 μm. Having a thickness within this range tends to easily ensure sufficient adhesion. From the above perspective, the film thickness is preferably in the range of 1 μm to 15 μm, and more preferably in the range of 3 μm to 15 μm.

[0183] In one embodiment, the elastic modulus of a 10 μm film obtained by coating and heating the resin composition (varnish) is preferably in the range of 0.5 GPa to 8.0 GPa at 35°C, more preferably in the range of 1.0 GPa to 5.0 GPa, and even more preferably in the range of 2.0 GPa to 4.5 GPa. The heating and drying process for forming the film can be carried out, for example, by heating at 50°C for 10 minutes followed by drying at 260°C for 1 hour. The elastic modulus is a value measured using a dynamic viscoelasticity measuring device. From the viewpoint of further improving the reliability of power semiconductor devices, the film preferably has appropriate flexibility. Therefore, in one embodiment, the elastic modulus of the film is further preferably in the range of 3.0 GPa to 4.5 GPa.

[0184] The elastic modulus can be measured, for example, using a dynamic viscoelasticity measuring device, the "Rheogel-E4000 type," manufactured by UBM Corporation. The aforementioned elastic modulus is, for example, a value obtained by coating and drying a film of a resin composition (varnish), under conditions of a measuring frequency of 10 MHz and a measuring temperature of 35°C.

[0185] The resin composition described in the above embodiments is suitable as a constituent material for semiconductor devices due to its excellent heat resistance and flexibility. For example, the above resin composition can be used to form insulating layers, adhesive layers, protective layers, etc., in semiconductor devices, resulting in semiconductor devices with excellent adhesion and reliability between components.

[0186] In one embodiment, the above-described resin composition can be suitably used to form an undercoating layer disposed between a sealing material and a substrate, or between a sealing material and a semiconductor element, in a semiconductor device. The adhesion between the components can be evaluated by shear strength.

[0187] In one embodiment, the shear strength between components having a base coating comprising the above-described resin composition at 260°C is preferably 11 MPa or more, more preferably 15 MPa or more, and even more preferably 17 MPa or more. If the shear strength at 260°C is 11 MPa or more, excellent adhesion can be easily obtained even when the above-described resin composition is used in a power semiconductor device.

[0188] In one embodiment, in a laminate having a base coating comprising the above-described resin composition and a resin sealing layer sequentially on a substrate, the shear strength of the substrate and the resin sealing layer at 260°C can be 11 MPa or higher. The laminate can be obtained by coating and drying a resin composition (varnish) on a substrate to form a film, and then forming a resin sealing layer on the film.

[0189] Shear strength can be measured, for example, using a shear strength testing apparatus (Nordson Advanced Technology Co., Ltd. 4000 series). For example, a sample can be used where a resin composition is coated and dried on a Ni substrate to form a film, and then an epoxy sealing resin is applied to the film to form a resin sealing layer with a diameter of 5 mm. Typical testing conditions include a hot stage temperature of 260°C and a probe speed of 3 mm / min. The substrate material and the sealing material constituting the resin sealing layer can also be appropriately modified.

[0190] During the measurement, a Cu substrate can be used instead of a Ni substrate, or a substrate formed by plating Ag on a Cu substrate can be used.

[0191] When the resin composition described above is used in a semiconductor device to form an undercoating layer between the sealing material and the substrate, or between the sealing material and the semiconductor element, as described above, from the viewpoint of suppressing stress caused by thermal expansion and contraction and improving adhesion, it is preferable that the difference in coefficient of linear expansion (CTE) between each component and the film containing the resin composition is small. From this viewpoint, in one embodiment, the CTE of the polyamide-imide resin is preferably in the range of 40 ppm / ℃ to 90 ppm / ℃, more preferably in the range of 50 ppm / ℃ to 70 ppm / ℃, and even more preferably in the range of 55 ppm / ℃ to 65 ppm / ℃. Furthermore, the CTE of the resin composition containing the polyamide-imide resin is also preferably within the above-mentioned range.

[0192] The CTE mentioned above is a value obtained by measuring a film obtained by coating and drying a varnish of a resin or resin composition. The measurement can be performed, for example, using a thermomechanical analyzer (TMA, Hitachi High-Tech Science "SS7100"). Regarding the measurement conditions, the chuck distance can be set to 10 mm, the load to 10 g, and the heating rate to 10 °C / min. The CTE specified in this specification is the value calculated by connecting the values ​​at 70 °C and 140 °C with a straight line and taking into account the slope.

[0193] Semiconductor Devices

[0194] One embodiment relates to a semiconductor device having a substrate and a dry film made using the resin composition of the above embodiment. The constituent components of the semiconductor device generally include a semiconductor element mounted on the substrate and a sealing member (sealing layer). The semiconductor element is typically made of inorganic materials such as semiconductor chips (Si, SiC, GaN), Cu, Ni plating, Ag plating, Au plating, Au / Pd / Ni plating, solder, sintered silver, sintered copper, Al wires, Au wires, and ceramic substrates (alumina, zirconium alumina, aluminum nitride, silicon nitride). The sealing layer is typically made of organic materials such as resin. Hereinafter, the sealing layer made of resin will be referred to as a resin sealing layer.

[0195] In the aforementioned semiconductor device, by forming a dry film using the resin composition of the above embodiment as a base coating between each constituent component, the adhesion between the constituent components can be easily improved. More specifically, for example, by forming a dry film of the above resin composition between the resin sealing layer and the substrate, or between the resin sealing layer and the semiconductor element, the adhesion between the components can be ensured, and peeling during cyclic testing can be prevented. From this perspective, in one embodiment, the semiconductor device preferably includes a substrate, a semiconductor element mounted on the substrate, a base coating disposed on at least the semiconductor element mounting surface of the substrate, and a resin sealing layer disposed on the base coating, wherein the base coating comprises a dry film formed using the resin composition for semiconductor devices of the above embodiment. The substrate may be a lead frame including chip pads and pins for mounting the semiconductor element, wherein the electrode pads of the semiconductor element and the pins of the lead frame are electrically connected via wires.

[0196] In one embodiment, the resin composition described above may also be suitably used as a constituent material for power semiconductor devices using the aforementioned silicon carbide (SiC) substrate or gallium nitride (GaN) substrate. When the power semiconductor device is constructed using the aforementioned resin composition, the reduction in the adhesion between components during thermal cycling tests can be easily suppressed.

[0197] Hereinafter, a representative structure of the semiconductor device according to the above embodiments will be specifically described with reference to the accompanying drawings. Figure 1 This is a schematic cross-sectional view illustrating one embodiment of a semiconductor device. Figure 1 The semiconductor device shown has a chip pad 1a, a semiconductor element 2, a base coating 3, leads 1b, wires 4, and a resin sealing layer 5. The base coating 3 is formed from the resin composition of the above embodiment. Figure 1 As shown, by providing a base coating 3 formed of the above-mentioned resin composition on the semiconductor element mounting surface (the surface of the pin 1b and the chip pad 1a on which the semiconductor element 2 is mounted) of the substrate 1 which is in contact with the resin sealing layer 5, the tightness between the components can be easily improved.

[0198] In one embodiment, the method for manufacturing a semiconductor device includes at least the steps of coating the surface of a substrate on which a semiconductor element is mounted with the resin composition of the above embodiment and drying it to form a base coating layer; and the step of forming a resin sealing layer on the base coating layer.

[0199] In the above embodiments, the primer layer is formed using the resin composition of the above embodiments. From a workability point of view, it is preferable to use a resin composition (varnish) containing polyamide-imide resin as a resin component. The primer layer can be obtained by applying the resin composition to a specified area and drying the coating.

[0200] The material of the lead frame, which includes the chip pads for mounting semiconductor elements and the pins, is not particularly limited and can be selected from materials well known in the art. From the viewpoint of suitability for power semiconductor devices, the chip pad material is preferably at least one selected from Ni or Cu. Additionally, one selected from Ni or Cu may also have an Ag plating on its surface. The pin material of the lead frame is preferably selected from Ni or Cu.

[0201] There are no particular limitations on the materials used in semiconductor devices; for example, they can be silicon wafers, silicon carbide wafers, etc.

[0202] The resin sealing layer can be formed using sealing materials well known in the art. For example, the resin sealing material can be a liquid or solid epoxy resin composition. The resin sealing layer can be formed, for example, using a resin sealing material and by transfer molding.

[0203] In another embodiment, the method for manufacturing a semiconductor device includes, for example, a step of coating and drying the resin composition of the above embodiment onto a semiconductor substrate having multiple identical wirings to form a resin layer; and a step of forming, as needed, rewiring on the resin layer that is electrically connected to electrodes on the semiconductor substrate. In addition to the above steps, the method may also include, as needed, a step of forming a protective layer (resin layer) on the rewiring or the resin layer using the resin composition of the above embodiment. Furthermore, in addition to the above steps, the method may also include, as needed, a step of forming external electrode terminals on the resin layer, and then, as needed, a step of cutting.

[0204] The coating method for the aforementioned resin layer (base coat) is not particularly limited, but spin coating, spray coating, or dispensing coating are preferred. The drying method for the aforementioned resin layer can be performed using methods known in the art. The resin composition of the above embodiments also exhibits excellent sputtering resistance, plating resistance, and alkali resistance, which are required in the process of forming redistribution. Therefore, the resin composition of the above embodiments can be suitably used as a material for any semiconductor device, not limited to the configuration of the semiconductor device described above.

[0205] Example

[0206] The present invention will be described in detail below through embodiments, but the present invention is not limited to the following embodiments, but includes various implementation methods.

[0207] <1> Synthesis of polyamide-imide resin

[0208] (Synthesis example 1)

[0209] Under a nitrogen gas flow, 25.1 g of 9,9-bis(4-aminophenyl)fluorene, 3.6 g of 4,4'-diaminodiphenylmethane, and 2.5 g of 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane were added to a 1-liter four-necked flask equipped with a thermometer, stirrer, nitrogen inlet pipe, and cooling pipe with an oil-water separator. Then, 284 g of N-methyl-2-pyrrolidone (hereinafter referred to as NMP) was added and dissolved to obtain a solution.

[0210] Next, while cooling the above solution at a temperature not exceeding 20°C, 21.1 g of trimellitic anhydride chloride (hereinafter referred to as TAC) was added. After stirring at room temperature for 2 hours, 12.1 g of triethylamine (hereinafter referred to as TEA) was added, and the reaction was carried out at room temperature for at least 12 hours to obtain a polyamic acid solution.

[0211] The obtained polyamic acid solution was further subjected to dehydration condensation at 180°C for 8 hours to obtain a polyamide-imide resin solution. The polyamide-imide resin solution was then injected into water, and the resulting precipitate was separated, pulverized, and dried to obtain powdered polyamide-imide resin (PAI-1). The obtained polyamide-imide resin powder (PAI-1) is soluble in a polar solvent (NMP) at room temperature (25°C).

[0212] The weight-average molecular weight (Mw) of the obtained polyamide-imide resin (PAI-1) was determined by gel permeation chromatography (hereinafter referred to as GPC) with conversion to standard polystyrene, and the result was Mw of 57,000 to 68,000.

[0213] It should be noted that the determination conditions for GPC are as follows.

[0214] Liquid delivery pump: LC-20AD manufactured by Shimadzu Corporation

[0215] UV-Vis detector: SPD-20A, UV 270nm, manufactured by Shimadzu Corporation.

[0216] Eluent: Tetrahydrofuran / Dimethylformamide = 1 / 1 (volume ratio) + 0.06M Phosphoric Acid + 0.06M Lithium Bromide

[0217] Columns: 2 x Gelpack GL-S300M DT-5 manufactured by Hitachi High Tech Co., Ltd.

[0218] Column dimensions: 8mm lD×300mm

[0219] Sample concentration: 5 mg / 1 mL

[0220] Flow rate: 1 mL / min; Column temperature: 40℃

[0221] Molecular weight standard material: Standard polystyrene

[0222] (Synthesis example 2)

[0223] In the preparation of the polyamide-imide resin (PAI-1) described in Synthesis Example 1, 9,9-bis(4-aminophenyl)fluorene was changed to 15.7 g and 4,4'-diaminodiphenylmethane was changed to 8.9 g. Otherwise, the same method as in Synthesis Example 1 was followed to obtain the powdered polyamide-imide resin (PAI-2).

[0224] The polyamide-imide resin powder (PAI-2) is soluble in a polar solvent (NMP) at room temperature (25°C). The weight-average molecular weight (Mw) of the obtained polyamide-imide resin (PAI-2) was determined by conversion to standard polystyrene, and the result was Mw was 72,000. The determination of Mw was performed in the same manner as described in Synthesis Example 1.

[0225] (Synthesis example 3)

[0226] In the preparation of the polyamide-imide resin (PAI-1) described in Synthesis Example 1, 9,9-bis(4-aminophenyl)fluorene was changed to 6.3 g and 4,4'-diaminodiphenylmethane was changed to 14.3 g. Otherwise, the same method as in Synthesis Example 1 was followed to obtain the powdered polyamide-imide resin (PAI-3).

[0227] The polyamide-imide resin powder (PAI-3) is soluble in a polar solvent (NMP) at room temperature (25°C). The weight-average molecular weight (Mw) of the obtained polyamide-imide resin (PAI-3) was determined by conversion to standard polystyrene, and the result was Mw = 100,000. The determination of Mw was performed in the same manner as described in Synthesis Example 1.

[0228] (Synthesis Example 4)

[0229] Under a nitrogen gas flow, 15.7 g of 9,9-bis(4-amino-3-methylphenyl)fluorene, 7.1 g of 1,5'-diaminonaphthalene, and 2.5 g of 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane were added to a 1-liter four-necked flask equipped with a thermometer, stirrer, nitrogen inlet pipe, and cooling pipe with an oil-water separator. Then, 250 g of NMP was added and dissolved to obtain a solution.

[0230] Next, while cooling the above solution at a temperature not exceeding 20°C, 21.1 g of TAC was added. After stirring at room temperature for 2 hours, 12.1 g of TEA was added, and the mixture was reacted at room temperature for at least 12 hours to prepare a polyamic acid solution.

[0231] The obtained polyamic acid solution was further subjected to dehydration condensation at 180°C for 8 hours to obtain a polyamide-imide resin solution. The polyamide-imide resin solution was then injected into water, and the resulting precipitate was separated, pulverized, and dried to obtain powdered polyamide-imide resin (PAI-5). The polyamide-imide resin powder (PAI-5) is soluble in a polar solvent (NMP) at room temperature (25°C).

[0232] The weight-average molecular weight (Mw) of the obtained polyamide-imide resin (PAI-5) was determined using GPC, converted to standard polystyrene, and the result was Mw was 65,000. The determination of Mw was performed in the same manner as described in Synthesis Example 1.

[0233] (Synthesis Example 5)

[0234] Under a nitrogen gas flow, 15.7 g of 9,9-bis(4-amino-3-methylphenyl)fluorene, 4.9 g of 1,4-phenylenediamine, and 2.5 g of 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane were added to a 1-liter four-necked flask equipped with a thermometer, stirrer, nitrogen inlet pipe, and cooling pipe with an oil-water separator. Then, 238 g of NMP was added and dissolved to obtain a solution.

[0235] Next, while cooling the above solution at a temperature not exceeding 20°C, 21.1 g of TAC was added. After stirring at room temperature for 2 hours, 12.1 g of TEA was added, and the mixture was reacted at room temperature for at least 12 hours to prepare a polyamic acid solution.

[0236] The obtained polyamic acid solution was further subjected to dehydration condensation at 180°C for 8 hours to obtain a polyamide-imide resin solution. The polyamide-imide resin solution was then injected into water, and the resulting precipitate was separated, pulverized, and dried to obtain powdered polyamide-imide resin (PAI-5). The polyamide-imide resin powder (PAI-5) is soluble in a polar solvent (NMP) at room temperature (25°C).

[0237] The weight-average molecular weight (Mw) of the obtained polyamide-imide resin (PAI-5) was determined using GPC, converted to standard polystyrene, and the result was Mw was 42,000. The determination of Mw was performed in the same manner as described in Synthesis Example 1.

[0238] (Synthesis Example 6)

[0239] Under a nitrogen gas flow, 102.4 g of 2,2-bis[4-(4-aminophenoxy)phenyl]propane and 6.9 g of 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane were added to a 1-liter four-necked flask equipped with a thermometer, stirrer, nitrogen inlet pipe, and cooling pipe with an oil-water separator. Then, 700 g of NMP was added and dissolved to obtain a solution.

[0240] Next, while cooling the above solution to a temperature not exceeding 20°C, 59.0 g of TAC was added. After stirring at room temperature for 1 hour, 34.0 g of TEA was added while cooling the reaction solution to a temperature not exceeding 20°C, and the mixture was reacted at room temperature for 3 hours to prepare a polyamic acid solution.

[0241] The obtained polyamic acid solution was further subjected to dehydration condensation at 190°C for 6 hours to produce a polyamide-imide resin solution.

[0242] The varnish of the above-mentioned polyamide-imide resin was injected into water, and the resulting precipitate was separated, pulverized, and dried to obtain powdered polyamide-imide resin (PAI-6). The weight-average molecular weight (Mw) of the obtained polyamide-imide resin (PAI-6) was determined by gel permeation chromatography (GPC) with conversion to standard polystyrene, and the result was Mw was 75,000. The determination of Mw was performed in the same manner as described in Synthesis Example 1.

[0243] <2> Preparation of polyamide-imide resin composition

[0244] In the examples and comparative examples shown below, polyamide-imide resin compositions (primer varnish for semiconductor devices) were prepared using polyamide-imide resin powder (PAI-1) to polyamide-imide resin powder (PAI-6) prepared in the previous synthesis examples 1 to 6, respectively.

[0245] (Example 1)

[0246] Under a nitrogen gas flow, 12 g of polyamide-imide resin powder (PAI-1) obtained in Synthesis Example 1, 60.9 g of N-methyl-2-pyrrolidone, 26.1 g of butyl cellosolve acetate, and 1.2 g of silane coupling agent (product name KBM-402 (3-glycidoxypropylmethyldimethoxysilane) manufactured by Shin-Etsu Chemical Industry Co., Ltd.) were added to a 0.5 L four-necked flask and stirred for 12 hours to obtain a yellow reaction mixture. The obtained yellow reaction mixture was filled into a KST-47 filter (manufactured by Advantec Co., Ltd.) and pressure filtered at a pressure of 0.3 MPa to obtain a primer varnish for semiconductor devices (P-1).

[0247] (Example 2)

[0248] The polyamide-imide resin powder (PAI-1) used in Example 1 was replaced with (PAI-2) obtained in Synthesis Example 2. Otherwise, all procedures were carried out in the same manner as in Example 1 to prepare a primer varnish (P-2) for semiconductor devices.

[0249] (Example 3)

[0250] The polyamide-imide resin powder (PAI-1) used in Example 1 was replaced with (PAI-3) obtained in Synthesis Example 3. Otherwise, all other procedures were carried out in the same manner as in Example 1 to prepare a primer varnish (P-3) for semiconductor devices.

[0251] (Example 4)

[0252] The polyamide-imide resin powder (PAI-1) used in Example 1 was replaced with (PAI-4) obtained in Synthesis Example 4. Otherwise, all procedures were carried out in the same manner as in Example 1 to prepare a primer varnish (P-4) for semiconductor devices.

[0253] (Example 5)

[0254] The polyamide-imide resin powder (PAI-1) used in Example 1 was replaced with (PAI-5) obtained in Synthesis Example 5. Otherwise, all other procedures were carried out in the same manner as in Example 1 to prepare a primer varnish (P-5) for semiconductor devices.

[0255] (Comparative Example 1)

[0256] The polyamide-imide resin powder (PAI-1) used in Example 1 was changed to (PAI-6) obtained in Synthesis Example 6, and the solvent was changed to 35g of N-methyl-2-pyrrolidone and 52g of butyl cellosolve acetate. Otherwise, all the steps were carried out in the same manner as in Example 1 to prepare a primer varnish for semiconductor devices (P-6).

[0257] <3> Evaluation of polyamide-imide resin compositions (primer varnish for semiconductor devices)

[0258] Evaluate the various characteristics according to the following.

[0259] (Elastic modulus)

[0260] Using a bar coater, the semiconductor devices obtained in Examples 1-5 and Comparative Example 1 were coated onto a substrate with primer varnish (P-1) to (P-6) and then heated and dried to obtain a dried film with a thickness of 10 μm. The heating and drying for forming the above-mentioned dried film was carried out under the conditions of heating at 50°C for 10 minutes and then drying at 260°C for 1 hour.

[0261] The dried film obtained in the above manner was used as a sample for the following measurements.

[0262] The sample was placed on a dynamic viscoelasticity measuring apparatus (Rheogel-E4000) manufactured by UBM Corporation to determine the elastic modulus of the polyamide-imide resin. The elastic modulus was determined under conditions of a chuck distance of 20 mm, a temperature of 35°C, and a measurement frequency of 10 MHz. The measured values ​​are shown in Table 1.

[0263] (Glass transition temperature)

[0264] Using a bar coater, the semiconductor devices obtained in Examples 1-5 and Comparative Example 1 were coated onto a substrate with primer varnish (P-1) to (P-6) and then heated and dried to obtain a dried film with a thickness of 10 μm. The heating and drying for forming the above-mentioned dried film was carried out under the conditions of heating at 50°C for 10 minutes and then drying at 260°C for 1 hour.

[0265] The dried film obtained in the above manner was used as the sample for the following measurements. The measurements were performed using a thermomechanical analysis apparatus (TMA, Hitachi High-Tech Science “SS7100”) under the conditions of a chuck distance of 10 mm, a load of 10 g, and a heating rate of 10 °C / min. The inflection point of the linear expansion coefficient from α1 to α2 obtained in the TMA measurement was taken as the glass transition temperature.

[0266] (Coefficient of linear expansion)

[0267] Using a rod coater, the semiconductor devices obtained in Examples 1-5 and Comparative Example 1 were coated onto a substrate with primer varnish (P-1) to (P-6) and then heated and dried to obtain a dried film with a thickness of 10 μm. To form the dried film, heating was performed at 50°C for 10 minutes, followed by drying at 260°C for 1 hour.

[0268] The dried film obtained in the above manner was used as the sample for measurement, and the coefficient of linear expansion (CTE) was determined. The measurement was performed using a thermomechanical analysis apparatus (TMA, Hitachi High-Tech Science "SS7100") under conditions of a chuck distance of 10 mm, a load of 10 g, and a heating rate of 10 °C / min. The displacements at 70 °C and 140 °C were connected by a straight line, and the value calculated from the slope was taken as the CTE value.

[0269] (Seam tightness (shear strength))

[0270] For the semiconductor device primers (P-1) to (P-6) obtained in Examples 1 to 5 and Comparative Example 1, the adhesion was evaluated using a shear strength testing device of the 4000 series manufactured by ARCTEC Corporation.

[0271] Specifically, firstly, the aforementioned primer varnish is applied to a Ni substrate using a spray coating apparatus (model: SV91) manufactured by SAN-EI TECH Co., Ltd., and then heated and dried to obtain a dried film. The thickness of the dried film is 10 μm.

[0272] Next, a φ5mm resin sealing layer was formed on the aforementioned dried film to obtain a sample for testing. An epoxy-based sealing resin (CEL-420HFC) manufactured by Showa Denko Materials Co., Ltd. was used as the sealing material.

[0273] The obtained test sample was placed on the hot stage of a 4000 series shear strength measuring apparatus manufactured by ARCTEC Corporation, and the shear strength was measured. The measurement was carried out at a temperature of 260°C and a probe speed of 3 mm / min. The results are shown in Table 1.

[0274] Based on the shear strength test results at 260℃, the airtightness in the high-temperature region was evaluated according to the following criteria. The evaluation results are shown in Table 1.

[0275] <Standards for Sealing in High-Temperature Areas>

[0276] A: The shear strength at 260℃ is above 18.0 MPa.

[0277] B: The shear strength at 260℃ is above 11MPa and less than 18.0MPa.

[0278] C: The shear strength at 260℃ is less than 11MPa.

[0279] (Reliability Evaluation (Moisture Absorption Reflow Soldering Test))

[0280] For the primer varnishes (P-1) to (P-6) for semiconductor devices obtained in Examples 1 to 5 and Comparative Example 1, moisture absorption reflow soldering tests were performed.

[0281] Specifically, firstly, after assembling the package containing the Si chip on the Cu lead frame, the aforementioned primer varnish is applied and dried using a spray coating apparatus (model: SV91) manufactured by SAN-EI TECH Co., Ltd., to obtain a dried film. Regarding the drying conditions, the drying time was set to 1 hour at a temperature of 260°C.

[0282] Next, a resin sealing layer was formed on the aforementioned dry film using "CEL-8240" manufactured by Showa Denko Materials Co., Ltd. as a sealing material, and an evaluation sample was obtained.

[0283] Next, using the obtained evaluation samples, a moisture absorption reflow soldering test was conducted under the following conditions.

[0284] Moisture absorption conditions: JEDEC MSL 1 (85℃ / 85%RH×168 hours),

[0285] Reflow soldering conditions: 260℃ / 10 seconds × 3 times

[0286] Next, in the semiconductor device before and after the reliability test (moisture-absorbing reflow soldering test), high-precision ultrasonic microscopy (C-SAM) was used to observe whether delamination occurred between the resin sealant, the resin drying film (base coat), and the lead frame. The results are shown in Table 1.

[0287] Table 1 shows the evaluation results of the reliability tests, presented as the number of samples (numerator) where peeling was confirmed relative to the total number of samples evaluated (denominator). The conditions under which the observations were made are as follows.

[0288] Apparatus: High-precision ultrasonic microscope (C-SAM), Sonoscan D9600, vibration frequency 30MHz

[0289] Conditions: Room temperature (25℃±5℃), using pure water.

[0290] The results of the evaluation of each characteristic in Examples 1 to 5 and Comparative Example 1 are summarized in Table 1.

[0291] [Table 1]

[0292]

[0293] In Table 1, structural units I'-II' derived from diamine are structural units derived from 2,2-bis[4-(4-aminophenoxy)phenyl]propane.

[0294] As described above, the resin compositions of the present invention (Examples 1-5) exhibit excellent adhesion even at a high temperature of 260°C. On the other hand, the resin composition of Comparative Example 1 has a lower Tg than that of Examples 1-5, resulting in significantly poor adhesion in the high-temperature test at 260°C. The resin composition of Comparative Example 1 uses a polyamide-imide resin that does not have a caloric fluorene backbone.

[0295] Furthermore, according to the reliability test results based on the moisture absorption reflow soldering test in Examples 1-3, it can be seen that Tg can be easily increased by adjusting the ratio of structural unit (Ia) to structural unit (IIa). Moreover, as seen in Examples 1, 4, and 5, it can be seen that the sealing performance is excellent under high-temperature conditions when Tg exceeds 300°C, and good results can also be obtained in the moisture absorption reflow soldering test, easily improving reliability.

[0296] As can be seen from the above, according to the present invention, by including structural units having a fluorene skeleton with a caloric structure and a combination of specific structural units in a polyamide-imide resin, a resin and resin composition with excellent adhesion in high-temperature regions and improved reliability of semiconductor devices can be provided.

[0297] Explanation of reference numerals in the attached figures

[0298] 1: Substrate;

[0299] 1a: Chip pad;

[0300] 1b: Pin;

[0301] 2: Semiconductor components;

[0302] 3: Primer coating;

[0303] 4: Wire;

[0304] 5: Resin sealing layer.

Claims

1. A polyamide-imide resin comprising: The structural unit (Ia) represented by the following formula Selected from at least one of the structural units (IIa), (IIb), and (IIc) represented by the following formulas. The structural unit (IIIa) represented by the following formula, and The structural unit (IVa) is represented by the following formula. The polyamide-imide resin is obtained by reacting a diamine component with an acid component. In the polyamide-imide resin, relative to the total amount of structural units derived from the diamine component, the proportion of structural unit (Ia) is 55 mol% to 85 mol%, the proportion of at least one selected from structural units (IIa), (IIb), and (IIc) is 10 mol% to 45 mol%, the proportion of structural unit (IIIa) is 5 mol% to 15 mol%, and the total proportion of structural unit (Ia), the proportion of at least one selected from structural units (IIa), (IIb), and (IIc), and the proportion of structural unit (IIIa) is 100 mol%. In formula (Ia), X independently represents a hydrogen atom or a substituent selected from halogen atoms, alkyl groups having 1 to 9 carbon atoms, alkoxy groups having 1 to 9 carbon atoms, and hydroxyalkyl groups; In formulas (IIa), (IIb) and (IIc), S independently represents an alkyl group having 1 to 3 carbon atoms, a represents 0, 1, 3 or 4, b represents an integer from 0 to 3, and c represents an integer from 0 to 4. In formula (IIIa), R independently represents a hydrogen atom or a substituent selected from alkyl groups having 1 to 9 carbon atoms, alkoxy groups having 1 to 9 carbon atoms, and halogen atoms, and n represents an integer from 1 to 6. 。 2. The polyamide-imide resin according to claim 1, wherein, The coefficient of linear expansion is 40 ppm / ℃~70 ppm / ℃.

3. The polyamide-imide resin according to claim 1 or 2, wherein, Based on the total amount of the structural unit (Ia) and at least one selected from the structural units (IIa), (IIb) and (IIc), the proportion of the structural unit (Ia) is 80 mol% or more.

4. The polyamide-imide resin according to claim 1 or 2, wherein, The glass transition temperature is above 250℃.

5. The polyamide-imide resin according to claim 1 or 2, wherein, The glass transition temperature is above 300℃.

6. A polyamide-imide resin composition comprising the polyamide-imide resin according to any one of claims 1 to 5, and a solvent.

7. A semiconductor device comprising a substrate and a film formed using the polyamide-imide resin composition of claim 6.

8. The semiconductor device according to claim 7, further comprising a resin sealing layer.

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