JP7342355B2 - Resin composition and semiconductor device - Google Patents

Description

One embodiment of the present disclosure relates to a resin composition that has excellent insulation properties, flexibility, and thick film forming properties. Another embodiment of the present disclosure relates to a highly reliable semiconductor device using the above resin composition.

Polyimide resins, polyamide resins, and polyamideimide resins are known as typical heat-resistant resins and are used for various purposes. Polyimide resins, polyamide resins, and polyamideimide resins have excellent chemical resistance and mechanical properties in addition to heat resistance. Therefore, these resins are widely used in the electronics field, for example, as materials for surface protection films or interlayer insulating films of semiconductor elements.

In recent years, power semiconductor devices have become smaller and at the same time have larger currents. When the current increases, leakage current may occur from circuits or elements, and it is widely known that leakage current causes failure of power semiconductor devices. Therefore, from the viewpoint of reliability of semiconductor devices, there is a strong desire to improve the insulation properties of power semiconductor devices.

In order to improve the insulation properties of power semiconductor devices, we are forming insulation films using resins such as polyimide resin, polyamide resin, and polyamideimide resin, and by securing insulation properties partially in the necessary locations, Methods of preventing the occurrence of leakage current between various members during operation of the device are being studied.

In the above method, the insulating film is formed by applying a solvent solution (varnish) of the resin to the power module before sealing, and then drying the obtained coating film. As a method for applying the solvent solution of the resin, general methods such as dispensing, dipping, potting, spray coating, and spin coating are used.

Japanese Unexamined Patent Publication No. 2-173073

However, in recent years, the current handled by the power semiconductor device itself has increased due to an increase in the current flowing through the power semiconductor device or a change in the substrate material from Si to SiC, for example. As a result, it has become difficult to obtain sufficiently satisfactory insulation and flexibility with conventional resins, and improvements in resins are desired. In particular, from the viewpoint of ensuring sufficient insulation, there is a need for a resin that can form an insulating film with sufficient thickness at the required location.

If the thickness of the resin coating forming the insulating film is not sufficient, it becomes difficult to ensure insulation between each member. As a result, for example, leakage current occurs in the power semiconductor device, causing malfunction. Generally, in order to ensure a sufficient film thickness, a method is known in which inorganic filler is dispersed within a resin paste (Patent Document 1). However, when the above method is applied, the electrical current passes through the interface of the inorganic filler, which tends to reduce the insulation properties of the coating film. Therefore, in order to obtain excellent insulating properties, it is necessary to strike a balance between the insulating properties of the resin itself and the ability to form a thick film so that a desired film thickness can be easily obtained during coating film formation. Furthermore, from the viewpoint of obtaining excellent reliability in semiconductor devices, it is also necessary that the coating film obtained from the resin has excellent flexibility.

From the above, the present disclosure provides a resin composition that has excellent insulation properties, flexibility, and thick film forming properties. Further, the present disclosure provides a highly reliable semiconductor device using the above resin composition.

The inventors conducted various studies on resin compositions containing polyimide resin, polyamide resin, and polyamideimide resin as resins, and found that resins containing specific structural units have high insulation properties and excellent flexibility. The present inventors have discovered that it is possible to easily form a thick film having a desired thickness while also having properties, and have completed the present invention.
Embodiments of the present invention relate to the following. However, the present invention is not limited to the embodiments described below.

［式中、Ｒ_１～Ｒ_４は、それぞれ独立して、水素原子、又は、炭素数１～９のアルキル基、炭素数１～９のアルコキシ基、及びハロゲン原子からなる群から選択される１種以上の置換基を表し、Ｘは、単結合、又は以下から選択される２価の有機基である。

（式中、Ｒ_５及びＲ_６は、それぞれ独立して、水素原子、又は、炭素数１～９のアルキル基、トリフルオロメチル基、トリクロロメチル基、及びフェニル基からなる群から選択される１種以上の置換基である。）]

［式中、Ｒ_７～Ｒ_１０は、それぞれ独立して、水素原子、又は置換基を表し、Ｒ_１１及びＲ_１２は、それぞれ独立して、２価の炭化水素基を表し、ｍは１以上の整数である。］ One embodiment is (A) a polyimide resin containing a structural unit represented by the following formula (Ia) and a structural unit represented by the following formula (IIa), and having a weight average molecular weight of 100,000 or more, The present invention relates to a resin composition containing a resin component containing at least one selected from the group consisting of polyamide resins and polyamideimide resins, and (B) an organic solvent.

[In the formula, R ₁ to R ₄ are each independently selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 9 carbon atoms, an alkoxy group having 1 to 9 carbon atoms, and a halogen atom. It represents one or more substituents, and X is a single bond or a divalent organic group selected from the following.

(wherein R ₅ and R ₆ are each independently selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 9 carbon atoms, a trifluoromethyl group, a trichloromethyl group, and a phenyl group) It is a substituent of more than one species.)]

[In the formula, R ₇ to R ₁₀ each independently represent a hydrogen atom or a substituent, R ₁₁ and R ₁₂ each independently represent a divalent hydrocarbon group, and m is 1 or more is an integer. ]

In the above embodiment, the polyimide resin, the polyamide resin, and the polyamideimide resin are based on the total number of moles of the structural unit represented by the above formula (Ia) and the structural unit represented by the above formula (IIa). , preferably contains 3 to 7 mol% of the structural unit represented by the above formula (IIa).

In the above embodiment, the polyamideimide resin preferably further includes a structural unit represented by the following formula (IIIa).

In the above embodiment, the dielectric breakdown voltage of the film obtained by drying is preferably 150 kV/mm or more.

In the above embodiment, the glass transition temperature of the polyimide resin, the polyamide resin, and the polyamideimide resin is preferably 200° C. or higher, respectively.

In the above embodiment, the elastic modulus of the membrane obtained by drying at 35° C. is preferably 0.5 to 3.0 GPa.

One embodiment relates to a semiconductor device having a film formed on the surface of a component using the resin composition of the above embodiment.

According to the present invention, it is possible to provide a resin composition that has excellent insulation properties, flexibility, and thick film forming properties. Further, according to the present invention, a highly reliable semiconductor device can be provided using the resin composition.

FIG. 1 is a schematic cross-sectional view showing an example of a semiconductor device according to an embodiment. FIG. 2 is a schematic cross-sectional view showing an example of a semiconductor device according to an embodiment.

Hereinafter, embodiments of the present invention will be described in more detail, but the present invention is not limited to the following and includes various embodiments.
1. Resin composition One embodiment includes (A) a resin component containing at least one selected from the group consisting of polyimide resin, polyamide resin, and polyamideimide resin, each having two specific types of structural units, and (B) The present invention relates to a resin composition containing an organic solvent. Each component will be specifically explained below.

(A) Resin component The resin component constituting the resin composition includes a structural unit represented by the following formula (Ia) and a structural unit represented by the following formula (IIa), and has a weight average molecular weight of 100, 000 or more selected from the group consisting of polyimide resin, polyamide resin, and polyamideimide resin.

In the formula, R ₁ to R ₄ are each independently a hydrogen atom or a substituent. The substituent is one or more selected from the group consisting of an alkyl group having 1 to 9 carbon atoms, an alkoxy group having 1 to 9 carbon atoms, and a halogen atom.
In one embodiment, each of R ₁ to R ₄ is preferably a hydrogen atom. In another embodiment, R ₁ to R ₄ are preferably each independently an alkyl group having 1 to 9 carbon atoms, an alkoxy group having 1 to 9 carbon atoms, or a halogen atom. The alkyl group and the alkoxy group may have a linear structure, a branched structure, or a cyclic structure. The alkyl group and the alkoxy group more preferably have 1 to 6 carbon atoms, and even more preferably 1 to 3 carbon atoms.
The halogen atom may be a fluorine atom, a chlorine atom, or a bromine atom.

式中、Ｒ_５及びＲ_６は、それぞれ独立して、水素原子、又は置換基である。置換基は、炭素数１～９のアルキル基、トリフルオロメチル基、トリクロロメチル基、及びフェニル基からなる群から選択される１種以上であってよい。上記アルキル基は、直鎖構造、分岐構造、及び環状構造のいずれであってもよい。一実施形態において、式中、Ｒ_５及びＲ_６は、それぞれ独立して、炭素数１～６のアルキル基であることが好ましく、炭素数１～３のアルキル基であることがより好ましく、炭素数１又は２のアルキル基であることがさらに好ましい。 X is a single bond or a divalent organic group selected from the following.

In the formula, R ₅ and R ₆ are each independently a hydrogen atom or a substituent. The substituent may be one or more selected from the group consisting of an alkyl group having 1 to 9 carbon atoms, a trifluoromethyl group, a trichloromethyl group, and a phenyl group. The alkyl group may have a linear structure, a branched structure, or a cyclic structure. In one embodiment, in the formula, R ₅ and R ₆ are each independently preferably an alkyl group having 1 to 6 carbon atoms, more preferably an alkyl group having 1 to 3 carbon atoms, More preferably, it is an alkyl group of number 1 or 2.

式中、Ｒ_７～Ｒ_１０は、それぞれ独立して、水素原子、又は置換基である。置換基は、互いに同一であっても、異なっていてもよい。Ｒ_１１及びＲ_１２は、それぞれ独立して、２価の炭化水素基を表し、互いに同一であっても、異なっていてもよい。ｍは１以上の整数である。

In the formula, R ₇ to R ₁₀ are each independently a hydrogen atom or a substituent. The substituents may be the same or different from each other. R ₁₁ and R ₁₂ each independently represent a divalent hydrocarbon group, and may be the same or different. m is an integer of 1 or more.

In one embodiment, R ₇ to R ₁₀ are preferably each independently a substituent. The substituent may be at least one selected from the group consisting of an alkyl group having 1 to 9 carbon atoms, an alkoxy group having 1 to 9 carbon atoms, and a halogen atom. The alkyl group and the alkoxy group may have a linear structure, a branched structure, or a cyclic structure. More preferably, R ₇ to R ₁₀ are an alkyl group having 1 to 6 carbon atoms or a phenyl group. The hydrogen atom in the phenyl group may be substituted with an alkyl group having 1 to 6 carbon atoms. In one embodiment, each of R ₇ to R ₁₀ is preferably an alkyl group having 1 to 6 carbon atoms, more preferably an alkyl group having 1 to 3 carbon atoms.

The above R ₁₁ and R ₁₂ may each independently be an alkylene group having 1 to 9 carbon atoms or a phenylene group. The hydrogen atom in the phenylene group may be substituted with an alkyl group having 1 to 3 carbon atoms. The alkylene group may have a linear structure, a branched structure, or a cyclic structure. In one embodiment, R ₁₁ and R ₁₂ are each independently preferably a linear alkylene group having 1 to 6 carbon atoms, more preferably an alkylene group having 2 to 5 carbon atoms; More preferably, it is an alkylene group of number 3 or 4.
In the above formula, m is preferably from 1 to 100, more preferably from 1 to 40, even more preferably from 1 to 10.

In the above resin composition, a structural unit represented by the above formula (Ia) (hereinafter referred to as the structural unit (Ia)) and a structural unit represented by the above below formula (IIa) (hereinafter referred to as the structural unit (IIa) By using a resin component containing (referred to as ), it is possible to obtain excellent insulation properties and excellent flexibility. In one embodiment, the resin composition preferably contains at least a polyamide-imide resin among the resin components. When polyamide-imide resin is used, it is easy to obtain better heat resistance. Hereinafter, polyimide resin, polyamide resin, and polyamideimide resin may be collectively referred to as "resin."

The above resin can be manufactured using at least a compound represented by the following formula (I) and the following formula (II). In the formula, R ₁ to R ₁₂ , X, and m are as described above in formula (Ia) and formula (IIa), and Y is an amino group or an isocyanate group. That is, in one embodiment, the structural units (Ia) and (IIa) correspond to residues obtained by removing the amino group or isocyanate group from the compounds represented by the following formulas (I) and (II), and may directly bind to the amide bonding site or imide bonding site in the structure.

In one embodiment, the resin is preferably produced using at least a compound represented by the following formula (I-1) and the following formula (II-1). In the formula, R ₁ to R ₆ and R ₇ to R ₁₀ are as described above in formula (Ia) and formula (IIa), and Y is an amino group or an isocyanate group. n is an integer of 1 to 6, preferably 2 to 4, and more preferably 3 or 4.

In the above resin, the polyimide resin is, for example, a resin having an imide bond formed by a reaction between an acid component and a diamine component, and contains at least the compounds represented by (I) and (II) above as the diamine component. Other than the use, any resin may be manufactured without any particular limitation. For example, in the production of the above resin, 3,3',4,4'-biphenyltetracarboxylic dianhydride, 3,3',4,4'-diphenylsulfonetetracarboxylic dianhydride, etc. are used as the acid component. Aromatic carboxylic acid anhydrides can be preferably used.

In the above resin, the polyamide resin is, for example, a resin having an amide bond formed by a reaction between an acid component and a diamine component, and contains at least the compounds represented by (I) and (II) above as the diamine component. Other than the use, any resin may be manufactured without any particular limitation. For example, in the production of the above resin, aromatic dicarboxylic acids such as terephthalic acid and isophthalic acid can be suitably used as the acid component.

In the above resin, the polyamide-imide resin is a resin having an amide bond and an imide bond in the molecular skeleton, and is prepared by, for example, reacting a diamine component with an acid component containing tricarboxylic acid anhydride or its acid halide. (polyamic acid) and then dehydration and ring closure of the precursor. The above-mentioned polyamide-imide resin may be a resin produced without particular limitation, except that at least the compounds represented by (I) and (II) above are used as the above-mentioned diamine component or diisocyanate component.

Hereinafter, the resin will be explained in more detail using polyamideimide resin as an example. In the following description, polyimide resin, polyamide resin, and polyamideimide resin may be collectively referred to as resin.
In one embodiment, the polyamide-imide resin contains at least a tricarboxylic anhydride or an acid halide thereof as an acid component. The tricarboxylic acid anhydride may be a derivative of an aromatic compound, an aliphatic compound, or an alicyclic compound having three or more carboxyl groups in the molecule. Examples of tricarboxylic anhydrides include trimellitic anhydride and cyclohexanetricarboxylic anhydride. Among the tricarboxylic anhydrides, trimellitic anhydride is preferred from the viewpoints of cost, reactivity, solubility, and the like. Acid halides of trimellitic anhydride are also preferred. Tricarboxylic acid anhydride or its acid halide may be used alone or in combination of two or more types.

From this point of view, in one embodiment, the polyamide-imide resin preferably uses at least a tricarboxylic acid anhydride represented by the following formula (III) or an acid halide thereof as the acid component.

In the formula, R is a hydroxyl group or a halogen atom. The halogen atom may preferably be a chlorine atom or a bromine atom, with a chlorine atom being more preferred.
In one embodiment, when a diamine is used, it is preferable to use an acid halide of trimellitic anhydride as the acid component, and in particular, trimellitic anhydride chloride represented by the following formula (III-1) is used. It is particularly preferable.

From the above-mentioned viewpoint, it is preferable that the polyamide-imide resin includes a structural unit represented by the following formula (IIIa) (hereinafter referred to as structural unit (IIIa)).

The above structural unit (IIIa) can be derived by using trimellitic anhydride or its acid halide represented by the above formula (III) as the acid component and reacting it with a diamine component or a diisocyanate component. can.

In one embodiment, the polyamide-imide resin uses a compound represented by the above formula (I) and the above formula (II) as the diamine component or diisocyanate component, and a compound represented by the above formula (III) as the acid component. It may be a resin obtained using a compound that is In another embodiment, the polyamide-imide resin is obtained by further using other diamine components, diisocyanate components, and/or acid components in addition to the compounds represented by formulas (I) to (III) above. It may also be a resin that can be used.

For example, in addition to the compounds represented by the above formulas (I) and (II), the polyamide-imide resin may contain other aromatic diamines, aromatic diisocyanates, aliphatic diamines, or aliphatic diamines. The resin may be a resin obtained by further using a group diisocyanate, or a cycloaliphatic diamine or a cycloaliphatic diisocyanate.
Further, in addition to the compound represented by the above formula (III), the resin may be obtained by further using other acid components. Acid components that can be used may include, for example, the above-mentioned tricarboxylic acid anhydrides or acid halides thereof other than the compound represented by the above formula (III), and tricarboxylic acids such as trimellitic acid. In addition, tetracarboxylic dianhydrides such as pyromellitic anhydride and biphenyltetracarboxylic dianhydride, aromatic dicarboxylic acids such as terephthalic acid and isophthalic acid, alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid, and adipic acid. and aliphatic dicarboxylic acids such as sebacic acid.

As typified by polyamide-imide resin, in the resin, the structural unit (Ia) derived from the compound represented by formula (I) and the formula ( The proportion of the structural unit (IIa) derived from the compound represented by II) is preferably 93 to 97 mol%, more preferably 94 to 96 mol%. In one embodiment, the resin includes structural units (Ia) derived from a compound represented by formula (I) and structural units represented by formula (II) relative to the total amount of structural units derived from the diamine component and/or diisocyanate component. The proportion of the structural unit (IIa) derived from the compound may be 100 mol%. Here, the ratio (mol %) of the structural units is calculated from the number of moles of the amount of the monomer compound charged to each structural unit.

In one embodiment, as represented by a polyamide-imide resin, the proportion of the structural unit (IIa) in the resin is 3 to 7 moles based on the total number of moles of the structural unit (Ia) and the structural unit (IIa). %, more preferably 4 to 6 mol%. In this embodiment, the structural unit (Ia) and structural unit (IIa) in the resin are derived from compounds having structures represented by formulas (I-1) and (II-1) shown above. Structural units (I-1a) and (II-1a) are preferred. As described above, by adjusting the proportion of the structural unit (IIa) within the above range, it is possible to improve insulation properties and flexibility in a well-balanced manner.

In one embodiment, the polyamide-imide resin preferably includes structures (1A) and/or (1B) and structures (2A) and/or (2B) shown below. Such a polyamide-imide resin is produced by, for example, reacting trimellitic anhydride represented by formula (III) or its acid halide with two types of compounds represented by formula (I) and formula (II). You can get it after a while. In each formula, R ₁ to R _4, R ₇ to R _10, X and n are each as described above.

The polyamide-imide resin of the above embodiment more preferably includes the structure (1A-1) and/or (1B-1) and the structure (2A-1) and/or (2B-1) shown below.

Polyamideimide resin can be manufactured according to a known method and is not particularly limited. A polyamide-imide resin can be produced, for example, by reacting a diamine component and/or a diisocyanate component with an acid component. The diamine component, diisocyanate component, and acid component are as described above. The above reaction can be carried out without a solvent 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 adjusted as appropriate depending on the batch scale, the reaction conditions employed, and the like.

The organic solvent (reaction solvent) used in producing the polyamide-imide resin is not particularly limited. Examples of usable organic solvents include ether solvents such as diethylene glycol dimethyl ether, diethylene glycol diethyl ether, triethylene glycol dimethyl ether, triethylene glycol diethyl ether, ethylene glycol monoethyl ether acetate (ethylene glycol monoethyl ether acetate), dimethyl sulfoxide, Sulfur-containing solvents such as diethyl sulfoxide, dimethylsulfone, and sulfolane, cyclic ester (lactone) solvents such as γ-butyrolactone, ketone solvents such as cyclohexanone and methyl ethyl ketone, N-methyl-2-pyrrolidone, dimethylacetamide, 1, Examples include nitrogen-containing solvents such as 3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone, and aromatic hydrocarbon solvents such as toluene and xylene. One type of these organic solvents may be used alone, or two or more types may be used in combination. In one embodiment, it is preferable to select and use an organic solvent that can dissolve the resin to be produced, and it is preferable to use a polar solvent. The polar solvent will be described later, but for example, a nitrogen-containing solvent is preferable.

In one embodiment, the polyamide-imide resin is produced by first producing a precursor of the polyamide-imide resin by reacting an acid component with a diamine component, and then dehydrating and ring-closing this precursor to obtain a polyamide-imide resin. be able to. However, the method for ring-closing the precursor is not particularly limited, and methods well known in the art can be used. For example, a thermal ring-closing method in which the ring is dehydrated by heating under normal pressure or reduced pressure, a chemical ring-closing method in which a dehydrating agent such as acetic anhydride is used in the presence or absence of a catalyst, etc. can be used.

In the case of the thermal ring-closing method, it is preferable to carry out the reaction while removing water generated in the dehydration reaction from the system. During the dehydration reaction, the reaction solution may be heated to a temperature of 80°C to 400°C, preferably 100°C to 250°C. Alternatively, water may be removed azeotropically by using an organic solvent capable of azeotropic distillation with water, such as benzene, toluene, xylene, or the like.

In the case of the chemical ring closure method, the reaction is carried out at 0°C to 120°C, preferably 10°C to 80°C, in the presence of a chemical dehydrating agent. As the chemical dehydrating agent, it is preferable to use, for example, acid anhydrides such as acetic anhydride, propionic anhydride, butyric anhydride, and benzoic anhydride, and carbodiimide compounds such as dicyclohexylcarbodiimide. During the reaction, it is preferable to use a substance that promotes the cyclization reaction, such as pyridine, isoquinoline, trimethylamine, triethylamine, aminopyridine, and imidazole. The chemical dehydrating agent is used in an amount of 90 to 600 mol % based on the total amount of the diamine component, and the substance that promotes the cyclization reaction is used in an amount of 40 to 300 mol % based on the total amount of the diamine component. Further, dehydration catalysts such as phosphorus compounds such as triphenyl phosphite, tricyclohexyl phosphite, triphenyl phosphate, phosphoric acid, and phosphorus pentoxide, and boron compounds such as boric acid and boric anhydride may be used.

In the production of polyamide-imide resin, the usage ratio (molar ratio) of the acid component and the diamine component (diisocyanate component) is not particularly limited, and can be adjusted so that the reaction proceeds with just the right amount. In one embodiment, from the viewpoint of the molecular weight and degree of crosslinking of the polyamide-imide resin produced, it is preferable that the total amount of the diamine component is 0.80 to 1.10 mol relative to the total amount of the acid component 1.00 mol, The amount is more preferably 0.95 to 1.08 mol, and even more preferably 0.95 to 1.03 mol.

As represented by the polyamide-imide resin described above, the weight average molecular weight (Mw) of the resin constituting the resin composition is preferably 100,000 or more. On the other hand, although not particularly limited, from the viewpoint of solubility, Mw is preferably 160,000 or less. In one embodiment, the Mw of the resin is preferably in the range of 110,000 to 160,000. When the Mw of the resin is within the above range, a coating film with an optimal thickness can be easily formed during coating work. The Mw of the resin is more preferably in the range of 120,000 to 160,000, and even more preferably in the range of 130,000 to 150,000. "Mw" described herein is a value measured in terms of standard polystyrene using gel permeation chromatography.

In one embodiment, a film can be obtained by drying the resin composition. In forming the film, the method may include a step of applying the resin composition before drying the resin composition. Here, drying means volatilizing the organic solvent contained in the resin composition, for example, by natural drying or heat drying. Formation of a film by drying can be carried out, for example, according to the method described in Examples below. From the viewpoint of performing drying more fully, the drying step may be performed multiple times (twice or more).

In one embodiment, the thick film forming property of the coating film obtained using the above resin composition can be evaluated from the aspect ratio (=coating film thickness/coating film width) of the dry coating film obtained by dispensing. . From the viewpoint of making the film thick enough to easily obtain sufficient insulation, the aspect ratio is preferably 0.05 or more, more preferably 0.06 or more, and even more preferably 0.07 or more. The aspect ratio can be measured using, for example, a Dektak 6M surface profiler manufactured by ULVAC, Inc.

In one embodiment, the resin used to form the resin composition preferably has a glass transition temperature (Tg) of 180° C. or higher, as typified by the polyamide-imide resin described above. The "glass transition temperature (Tg)" described in this specification is a value obtained by conducting a dynamic viscoelasticity test using a film obtained by coating and drying a resin dissolved in a solvent. It is more preferable that the resin has a Tg of 200°C or higher. When the resin has a Tg of 200°C or higher, it becomes possible to obtain excellent reliability even in a heat cycle test that is generally conducted at a high temperature of 200°C or higher. Furthermore, when a power semiconductor device is constructed using the resin described above, it is possible to prevent the resin from softening due to heat generated during driving and from reducing adhesion.

In the resin composition, the resin is preferably soluble in an organic solvent at room temperature from the viewpoint of workability during film formation. In this specification, "soluble in an organic solvent at room temperature" means that there is no precipitate or turbidity when visually checking the solution obtained by adding an organic solvent to the resin and stirring the resin at room temperature. , which means that the entire solution becomes transparent. Here, the above-mentioned "room temperature" may be approximately in the range of 10°C to 40°C, preferably in the range of 20 to 30°C. In one embodiment, the above-mentioned "solution" refers to a solution obtained by adding 1 to 30 mg of the above-mentioned resin powder to 100 mL of an organic solvent, for example. The organic solvent will be described later.

(B) Organic Solvent The resin composition includes the resin component described above and an organic solvent. In this specification, the resin composition may also be referred to as a varnish.
The organic solvent is not particularly limited as long as it can dissolve a resin component such as polyamide-imide resin. In one embodiment, the organic solvent may be a solvent composed of polar molecules (sometimes referred to as a polar solvent). In one embodiment, the organic solvent constituting the resin composition may be the same as the reaction solvent used during the production of the resin.

As an example of an organic solvent,
Nitrogen-containing compounds such as N-methylpyrrolidone, dimethylacetamide , dimethylformamide, 1,3-dimethyltetrahydro-2(1H)-pyrimidinone, etc. Sulfur-containing compounds such as sulfolane, dimethylsulfoxide,
Lactones such as γ-butyrolactone, γ-valerolactone, γ-caprolactone, γ-heptalactone, α-acetyl-γ-butyrolactone, ε-caprolactone,
Ketones such as methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, acetophenone,
Polyhydric alcohols such as ethylene glycol and glycerin, and
ethers, i.e.
diethylene glycol dialkyl ethers such as diethylene glycol dimethyl ether, 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 monoalkyl ethers such as diethylene glycol monomethyl ether and diethylene glycol monoethyl ether;
Triethylene glycol monoalkyl ethers such as triethylene glycol monomethyl ether and triethylene glycol monoethyl ether; tetraethylene glycol monoalkyl ethers such as tetraethylene glycol monomethyl ether and tetraethylene glycol monoethyl ether; and ethylene glycol monomethyl Examples include ethers containing ethylene glycol monoalkyl ether acetate, such as ether acetate, ethylene glycol monoethyl ether acetate, and ethylene glycol monobutyl ether acetate (butyl cellosolve acetate).

These organic solvents may be used alone or in combination of two or more. In one embodiment, the organic solvent preferably contains a nitrogen-containing compound, with N-methylpyrrolidone being more preferred. In another embodiment, the organic solvent preferably contains ethers, with diethylene glycol dialkyl ether and ethylene glycol monoalkyl ether acetate being more preferred. In yet another embodiment, the organic solvent may be a mixed solvent containing a nitrogen-containing compound and an ether. For example, the organic solvent is preferably a mixed solvent of N-methylpyrrolidone and butyl cellosolve acetate, and the mixing ratio thereof is not particularly limited.

The blending amount of the organic solvent in the resin composition can be appropriately adjusted in consideration of the storage modulus or viscosity. In one embodiment, the organic solvent is preferably blended in an amount of 350 to 550 parts by weight based on 100 parts by weight of the total amount of resin components in the resin composition. More preferably, the organic solvent is blended in a proportion of 400 to 500 parts by weight based on 100 parts by weight of the total amount of polyamide-imide resin. By adjusting the blending amount of the organic solvent to the resin within the above range, the resin can be easily dissolved and a viscosity suitable for thickening the film can be easily obtained.

(Other ingredients)
Additional components such as colorants, additives such as coupling agents, and resin modifiers may be added to the resin composition (varnish), if necessary. When the resin composition contains an additional component, the amount of the additional component is preferably 50 parts by weight or less with respect to 100 parts by weight of the total amount of resin (solid component) in the resin composition. By controlling the blending amount of the additional component to 50 parts by weight or less, it becomes easy to suppress deterioration of the physical properties of the resulting coating film.

In one embodiment, the resin composition preferably further includes a coupling agent. When a coupling agent is used, it becomes easy to increase the adhesion to each member. The coupling agent that can be used is not particularly limited and may be silane-based, titanium-based, or aluminum-based, but silane-based coupling agents are most preferred.
The silane coupling agent is not particularly limited, and examples include vinyltrichlorosilane, vinyltris(β-methoxyethoxy)silane, vinyltriethoxysilane, vinyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxysilane, and γ-methacryloxypropyltrimethoxysilane. Roxypropylmethyldimethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-glycidoxypropylmethyldiethoxy Silane, N-β (aminoethyl) γ-aminopropyltrimethoxysilane, N-β (aminoethyl) γ-aminopropylmethyldimethoxysilane, γ-aminopropyltriethoxysilane, N-phenyl-γ-aminopropyltrimethoxy Silane, γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, 3-aminopropylmethyldiethoxysilane, 3-ureidopropyltriethoxysilane, 3-ureidopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane , 3-aminopropyl-tris[2-(2-methoxyethoxy)ethoxy]silane, N-methyl-3-aminopropyltrimethoxysilane, triaminopropyl-trimethoxysilane, 3-4,5-dihydroimidazole-1 -yl-propyltrimethoxysilane, 3-methacryloxypropyl-trimethoxysilane, 3-mercaptopropyl-methyldimethoxysilane, 3-chloropropyl-methyldimethoxysilane, 3-chloropropyl-dimethoxysilane, 3-cyanopropyl-tri Ethoxysilane, hexamethyldisilazane, N,O-bis(trimethylsilyl)acetamide, methyltrimethoxysilane, methyltriethoxysilane, ethyltrichlorosilane, n-propyltrimethoxysilane, isobutyltrimethoxysilane, amyltrichlorosilane, octyltrimethoxysilane Ethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, methyltri(methacryloyloxyethoxy)silane, methyltri(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, It may be vinylsilyl triisocyanate, phenylsilyl triisocyanate, tetraisocyanate silane, ethoxysilane isocyanate, and the like. One of these may be used alone or two or more may be used in combination.

The titanium-based coupling agent is not particularly limited and includes, for example, isopropyltrioctanoyl titanate, isopropyl dimethacrylylisostearoyl titanate, isopropyl tridodecylbenzenesulfonyl titanate, isopropyl isostearoyl diacryl titanate, isopropyl tri(dioctyl phosphate) titanate, Isopropyl tricumylphenyl titanate, isopropyl tris(dioctyl pyrophosphate) titanate, isopropyl tris(n-aminoethyl) titanate, tetraisopropyl bis(dioctyl phosphite) titanate, tetraoctyl bis(ditridecyl phosphite) titanate, tetra(2, 2-diallyloxymethyl-1-butyl)bis(ditridecyl)phosphite titanate, dicumylphenyloxyacetate titanate, bis(dioctylpyrophosphate)oxyacetate titanate, tetraisopropyl titanate, tetra-n-butyl titanate, butyl titanate dimer, tetra( 2-ethylhexyl) titanate, titanium acetylacetonate, polytitanium acetylacetonate, titanium octylene glycolate, titanium lactate ammonium salt, titanium lactate, titanium lactate ethyl ester, titanium titanium amineate, polyhydroxytitanium stearate, tetramethyl Ortho titanate, tetraethyl ortho titanate, tetrapropyl ortho titanate, tetraisobutyl ortho titanate, stearyl titanate, cresyl titanate monomer, cresyl titanate polymer, diisopropoxy-bis(2,4-pentadionate) titanium (IV) , diisopropyl-bis-triethanolaminotitanate, octylene glycol titanate, tetra-n-butoxytitanium polymer, tri-n-butoxytitanium monostearate polymer, tri-n-butoxytitanium monostearate, and the like. One of these may be used alone or two or more may be used in combination.

The aluminum-based coupling agent is not particularly limited, and includes, for example, ethyl acetoacetate aluminum diisopropylate, aluminum tris (ethylacetoacetate), alkyl acetoacetate aluminum diisopropylate, aluminum monoacetylacetate bis (ethylacetoacetate), Aluminum tris(acetylacetonate), aluminum-monoisopropoxymonooleoxyethylacetoacetate, aluminum-di-n-butoxide-mono-ethylacetoacetate, aluminum-di-iso-propoxide-mono-ethylacetoacetate, etc. It may be an aluminum chelate compound, aluminum alcoholate such as aluminum isopropylate, mono-sec-butoxyaluminum diisopropylate, aluminum-sec-butyrate, aluminum ethylate, and the like.

In one embodiment, the resin composition preferably has a dielectric breakdown voltage of 150 kV/mm or more at room temperature of the coating film after drying. The dielectric breakdown voltage is more preferably 180 kV/mm or more, and even more preferably 200 kV/mm or more. When the dielectric breakdown voltage is 150 kV/mm or more, even leakage current of the power semiconductor device can be sufficiently prevented, and it becomes possible to easily obtain excellent reliability in the semiconductor device.
In one embodiment, a dielectric breakdown voltage of 200 kV/mm or more can be achieved only with a resin component such as a polyamide-imide resin used in the resin composition. Therefore, the resin composition can be constructed without using an inorganic filler or the like. From this point of view, in one embodiment, the resin composition can be composed only of a resin component and an organic solvent.

"Dielectric breakdown voltage (kV/mm)" described in this specification is a value obtained by conducting a dielectric breakdown test using a resin composition or a resin film dissolved in a solvent. More specifically, measurements are performed using, for example, a sample obtained by coating and drying a resin composition (varnish) on an Al substrate to form a film. The conditions at the time of measurement are typically a pressure increase rate: 0.5 kV/sec (AC 50 Hz), electrode dimensions: high pressure side; φ20 mm sphere; low pressure side; metal plate; test atmosphere: in oil.

In one embodiment, the viscosity of the resin composition is preferably in the range of 7,000 to 15,000 mPa·s, more preferably in the range of 8,000 to 13,000 mPa·s. Here, the above viscosity is determined by measuring a varnish obtained by dissolving a resin in a solvent such that the non-volatile component (solid component) is 15 to 20% using an E-type viscometer at 25°C. This is a value obtained by measuring at 10 rpm. If the viscosity measured at 10 rpm is less than 7,000 mPa·s, it will be difficult to ensure a sufficient film thickness during coating. Furthermore, if the viscosity exceeds 15,000 mPa·s, it becomes difficult to form a uniform film during coating. In the above resin composition, a desired viscosity can be easily obtained by using a resin that contains a specific structural unit and has a weight average molecular weight of 100,000 or more.

The viscosity can be measured using, for example, a viscometer (RE type) manufactured by Toki Sangyo Co., Ltd. In the measurement, the measurement temperature is set at 25° C.±0.5° C., then 1 mL to 1.5 mL of the resin composition solution is placed in the viscometer, and the viscosity is recorded 10 minutes after the start of the measurement.

In one embodiment, the elastic modulus of the film obtained by applying and drying the resin composition (varnish) at 35° C. is preferably in the range of 0.5 to 3.0 GPa, preferably 1.0 to 3.0 GPa. It is more preferable that it is in the range of . The above elastic modulus is a value measured by a dynamic viscoelasticity measuring device. If the elastic modulus is less than 0.5 GPa, the film may become too soft and the reliability of the power semiconductor device may decrease. On the other hand, if the modulus of elasticity exceeds 3.0 GPa, the reliability of the power semiconductor device may decrease due to a decrease in stress relaxation properties of the film. From the viewpoint of obtaining good flexibility to further improve the reliability of the power semiconductor device, the elastic modulus is more preferably in the range of 2.2 GPa to 3.0 GPa, and most preferably in the range of 2.2 GPa to 2.8 GPa. preferable.

For the measurement of the elastic modulus, for example, a dynamic viscoelasticity measuring device "Rheogel-E4000 model" manufactured by UBM Corporation can be used. A sample was prepared by cutting a film obtained by applying and drying a resin composition (varnish) to a width of 4 mm, and using this sample, a test was performed at a distance between chucks of 20 mm, a measurement frequency of 10 MHz, and a measurement temperature of 35°C. carried out under measurement conditions.

2. Semiconductor Device The resin composition of the above embodiment has excellent heat resistance, as well as excellent insulation, flexibility, and thick film forming properties, and therefore can be suitably used as a constituent material of a semiconductor device. One embodiment relates to a semiconductor device having a film using the resin composition of the above embodiment on the surface of a component. For example, the film may constitute an insulating film in a semiconductor device. In addition, the above film may constitute an adhesive layer, a protective layer, or the like. A semiconductor device having the above film has excellent adhesion between each member and is highly reliable. In one embodiment, the above resin composition can be suitably used as a constituent material of a power semiconductor device using a silicon carbide (SiC) substrate or a gallium nitride (GaN) substrate.

1 and 2 are schematic cross-sectional views showing one embodiment of a semiconductor device. The semiconductor device shown in FIGS. 1 and 2 includes a die pad 1a, a semiconductor element 2, an insulating film 3a, 3b, or 3, a lead 1b, a wire 4, and a resin sealing layer 5. are each formed from the resin composition of the above embodiment.
In a semiconductor device, the location where leakage current is most likely to occur is at the lower end of a wire connected to a semiconductor element. Therefore, as shown in FIG. 1, in one embodiment, it is preferable that an insulating film 3a be provided at least at the lower end of the wire connected to the semiconductor element. As another embodiment, in addition to the insulating film 3a, an insulating film 3b may also be provided at the lower end of the wire connected to the lead 1b. As yet another embodiment, as shown in FIG. 2, in a semiconductor device, an insulating film 3 made of the resin composition may be provided on the upper surface, side surface, and upper surface of the die pad of the semiconductor element.
By providing the insulating film formed from the resin composition of the above embodiment in this way, leakage current generated within the semiconductor device can be more effectively prevented, and the reliability of the semiconductor device can be improved. can.

In one embodiment, a method for manufacturing a semiconductor device includes at least applying the resin composition of the embodiment described above on the surface of a substrate on which a semiconductor element is mounted and drying it to form an insulating film, and forming an insulating film on the surface of the insulating film. This includes forming a resin sealing layer.
In the above manufacturing method, from the viewpoint of workability, it is preferable that the above resin composition contains a polyamideimide resin as a resin component. The insulating film can be formed by applying the resin composition to a predetermined location and drying the coating. The resin composition can be applied using various coating methods. The coating method is not particularly limited, and examples thereof include a spray coating method, a potting method, a dipping method, and a dispensing method. In consideration of workability, potting method or dispense application is preferable.

The material of the substrate is not particularly limited and can be selected from materials well known in the art. From the viewpoint of manufacturing a power semiconductor device, the die pad material is preferably at least one selected from the group consisting of Ni, Cu, and Ag plating formed thereon. Preferably, the lead material of the lead frame is selected from the group consisting of Ni and Cu.
The material of the semiconductor element is not particularly limited, and may be, for example, a silicon wafer, a silicon carbide wafer, or the like.
The resin sealing layer can be made of a cured resin that is well known as a sealing material in the art. As the sealing material, for example, a liquid or solid epoxy resin composition can be used. The resin sealing layer can be formed, for example, by performing transfer molding using a sealing material.

In another embodiment, a method for manufacturing a semiconductor device includes, for example, applying and drying the polyamide-imide resin composition of the above embodiment onto a semiconductor substrate on which a plurality of wirings having the same structure are formed, and forming a resin layer; The method also includes forming rewiring on the resin layer to be electrically connected to the electrodes on the semiconductor substrate, if necessary. In addition to these steps, the method may also include forming a protective layer (resin layer) on the rewiring or on the resin layer using the resin composition, if necessary. Furthermore, in addition to the above steps, the method may include forming external electrode terminals on the resin layer as necessary, and then dicing as necessary.

In the above semiconductor device, the semiconductor element is not particularly limited, and may be, for example, a silicon wafer, a silicon carbide wafer, or the like. The method for applying the resin layer is not particularly limited, but preferably spin coating, spray coating, or dispense coating. The resin layer can be dried by a method known in the art. The resin composition of the above embodiment is also excellent in properties such as sputtering resistance, plating resistance, and alkali resistance required in the process of forming rewiring, so it is limited to the configuration of the semiconductor device described above. It can be suitably used as a constituent material of all kinds of semiconductor devices.

EXAMPLES Hereinafter, the present invention will be explained in detail with reference to Examples, but the present invention is not limited thereto.

1. Synthesis of polyamideimide resin (Synthesis example 1)
2,2-bis[4-(4-aminophenoxy)phenyl]propane was added to a 1 liter four-necked flask equipped with a thermometer, stirrer, nitrogen inlet tube, and condensing tube with oil/water separator under a nitrogen stream. and 3.45 g of 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane, and further added N-methyl-2-pyrrolidone (NMP). 700g was added and dissolved.
Next, 59.00 g of trimellitic acid chloride anhydride (TAC) was added while cooling the reaction solution so as not to exceed 20°C. After stirring at room temperature for 1 hour, 33.96 g of triethylamine (TEA) was added while cooling the reaction solution so as not to exceed 20° C., and the mixture was reacted at room temperature for 3 hours to prepare a polyamic acid solution.
The obtained polyamic acid solution was further subjected to a dehydration reaction at 190°C for 6 hours to prepare a polyamideimide resin solution. This polyamide-imide resin solution was poured into water, and the resulting precipitate was separated, crushed, and dried to obtain a powdered polyamide-imide resin (PAI-1). The weight average molecular weight (Mw) of the obtained polyamide-imide resin (PAI-1) was measured using gel permeation chromatography (GPC) in terms of standard polystyrene, and the Mw was 140,000.

The detailed conditions for measuring Mw are as follows.
Liquid pump: LC-20AD manufactured by Shimadzu Corporation
UV-Vis detector: SPD-20A manufactured by Shimadzu Corporation
Column: Shodex, KD-806M manufactured by Showa Denko K.K.
Eluent: NMP, manufactured by Mitsubishi Chemical Corporation Flow rate: 1 mL/min
Column temperature: 40℃
Molecular weight standard material: Standard polystyrene

(Synthesis example 2)
2,2-bis[4-(4-aminophenoxy)phenyl]propane was added to a 1 liter four-necked flask equipped with a thermometer, stirrer, nitrogen inlet tube, and condensing tube with oil/water separator under a nitrogen stream. and 2.07 g of 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane, and further added N-methyl-2-pyrrolidone (NMP). 700g was added and dissolved.
Next, 59.00 g of trimellitic acid chloride anhydride (TAC) was added while cooling the reaction solution so as not to exceed 20°C. After stirring at room temperature for 1 hour, 33.96 g of triethylamine (TEA) was added while cooling the reaction solution so as not to exceed 20° C., and the mixture was reacted at room temperature for 3 hours to prepare a polyamic acid solution.
The obtained polyamic acid solution was further subjected to a dehydration reaction at 190°C for 6 hours to prepare a polyamideimide resin solution. This polyamide-imide resin solution was poured into water, and the resulting precipitate was separated, ground, and dried to obtain a powdered polyamide-imide resin (PAI-2). The weight average molecular weight (Mw) of the obtained polyamide-imide resin (PAI-2) was measured using gel permeation chromatography (GPC) in terms of standard polystyrene, and the Mw was 150,000.

(Synthesis example 3)
2,2-bis[4-(4-aminophenoxy)phenyl]propane was added to a 1 liter four-necked flask equipped with a thermometer, stirrer, nitrogen inlet tube, and condensing tube with oil/water separator under a nitrogen stream. and 4.82 g of 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane, and further added N-methyl-2-pyrrolidone (NMP). 700g was added and dissolved.
Next, 59.00 g of trimellitic acid chloride anhydride (TAC) was added while cooling the reaction solution so as not to exceed 20°C. After stirring at room temperature for 1 hour, 33.96 g of triethylamine (TEA) was added while cooling the reaction solution so as not to exceed 20° C., and the mixture was reacted at room temperature for 3 hours to prepare a polyamic acid solution.
The obtained polyamic acid solution was further subjected to a dehydration reaction at 190°C for 6 hours to prepare a polyamideimide resin solution. This polyamide-imide resin solution was poured into water, and the resulting precipitate was separated, pulverized, and dried to obtain a powdered polyamide-imide resin (PAI-3). The weight average molecular weight (Mw) of the obtained polyamide-imide resin (PAI-3) was measured using gel permeation chromatography (GPC) in terms of standard polystyrene, and the Mw was 130,000.

(Synthesis example 4)
2,2-bis[4-(4-aminophenoxy)phenyl]propane was added to a 1 liter four-necked flask equipped with a thermometer, stirrer, nitrogen inlet tube, and condensing tube with oil/water separator under a nitrogen stream. and 6.89 g of 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane, and further added N-methyl-2-pyrrolidone (NMP). 700g was added and dissolved.
Next, 59.00 g of trimellitic acid chloride anhydride (TAC) was added while cooling the reaction solution so as not to exceed 20°C. After stirring at room temperature for 1 hour, 33.96 g of triethylamine (TEA) was added while cooling the reaction solution so as not to exceed 20° C., and the mixture was reacted at room temperature for 3 hours to prepare a polyamic acid solution.
The obtained polyamic acid solution was further subjected to a dehydration reaction at 190°C for 6 hours to prepare a polyamideimide resin solution. This polyamide-imide resin solution was poured into water, and the resulting precipitate was separated, ground, and dried to obtain a powdered polyamide-imide resin (PAI-4). The weight average molecular weight (Mw) of the obtained polyamide-imide resin (PAI-4) was measured using gel permeation chromatography (GPC) in terms of standard polystyrene, and the Mw was 85,000.

(Synthesis example 5)
2,2-bis[4-(4-aminophenoxy)phenyl]propane was added to a 1 liter four-necked flask equipped with a thermometer, stirrer, nitrogen inlet tube, and condensing tube with oil/water separator under a nitrogen stream. 113.77 g of N-methyl-2-pyrrolidone (NMP) was added and dissolved.
Next, 59.00 g of trimellitic acid chloride anhydride (TAC) was added while cooling the reaction solution so as not to exceed 20°C. After stirring at room temperature for 1 hour, 33.96 g of triethylamine (TEA) was added while cooling the reaction solution so as not to exceed 20° C., and the mixture was reacted at room temperature for 3 hours to prepare a polyamic acid solution.
The obtained polyamic acid solution was further subjected to a dehydration reaction at 190°C for 6 hours to prepare a polyamideimide resin solution. This polyamide-imide resin solution was poured into water, and the resulting precipitate was separated, ground, and dried to obtain a powdered polyamide-imide resin (PAI-5). The weight average molecular weight (Mw) of the obtained polyamide-imide resin (PAI-5) was measured using gel permeation chromatography (GPC) in terms of standard polystyrene, and the Mw was 180,000.

2. Preparation of polyamide-imide resin composition (Example 1)
At room temperature (25°C), 18 g of the polyamide-imide resin (PAI-1) obtained in Synthesis Example 1 and 32 g of N-methyl-2-pyrrolidone were placed in a 0.5 liter four-necked flask under a nitrogen stream. 8 g of butyl cellosolve acetate and 49.2 g of butyl cellosolve acetate were added thereto and stirred for 12 hours to obtain a polyamide-imide resin composition. When the obtained resin composition was visually confirmed at room temperature (25° C.), it was yellow and transparent. The above resin composition was filled into a filter (KST-47 manufactured by Advantech Co., Ltd.) and filtered under pressure at a pressure of 0.3 MPa to obtain a polyamide-imide resin composition (P-1).

(Example 2)
A polyamide-imide resin composition (P-2) was prepared in the same manner as in Example 1, except that the polyamide-imide resin (PAI-2) obtained in Synthesis Example 2 was used as the polyamide-imide resin. When the obtained resin composition was visually confirmed at room temperature (25° C.), it was yellow and transparent.

(Example 3)
A polyamide-imide resin composition (P-3) was prepared in the same manner as in Example 1, except that the polyamide-imide resin (PAI-3) obtained in Synthesis Example 3 was used as the polyamide-imide resin. When the obtained resin composition was visually confirmed at room temperature (25° C.), it was yellow and transparent.

(Comparative example 1)
A polyamide-imide resin composition (P-4) was prepared in the same manner as in Example 1, except that the polyamide-imide resin (PAI-4) obtained in Synthesis Example 4 was used as the polyamide-imide resin. When the obtained resin composition was visually confirmed at room temperature (25° C.), it was yellow and transparent.

(Comparative example 2)
At room temperature (25°C), 18 g of the polyamide-imide resin (PAI-4) obtained in Synthesis Example 4 and 32 g of N-methyl-2-pyrrolidone were placed in a 0.5 liter four-necked flask under a nitrogen stream. 8 g of butyl cellosolve acetate and 49.2 g of butyl cellosolve acetate were added thereto and stirred for 12 hours to obtain a polyamide-imide resin composition. When the obtained resin composition was visually confirmed at room temperature (25° C.), it was yellow and transparent.
10 g of silica filler (SC2050/manufactured by Admatex Co., Ltd.) was added to the resin composition, and the mixture was stirred using a disper (5,000 rpm/10 minutes). Thereafter, it was filled in a filter (KST-47 manufactured by Advantech Co., Ltd.) and subjected to pressure filtration at a pressure of 0.3 MPa to obtain a polyamide-imide resin composition (P-5).

(Comparative example 3)
A polyamide-imide resin composition (P-6) was prepared in the same manner as in Example 1, except that the polyamide-imide resin (PAI-5) obtained in Synthesis Example 5 was used as the polyamide-imide resin. When the obtained resin composition was visually confirmed at room temperature (25° C.), it was yellow and transparent.

3. Characteristic evaluation of polyamide-imide resin compositions Using each of the polyamide-imide resin compositions obtained in Examples 1 to 3 and Comparative Examples 1 to 3, various properties were evaluated according to the following. The results are shown in Table 1.

(viscosity)
The viscosity of each polyamide-imide resin composition obtained in Examples 1 to 3 and Comparative Examples 1 to 3 was measured using a viscometer (RE type) manufactured by Toki Sangyo Co., Ltd. under the following conditions.
Sampling amount: 1.2mL
Measurement temperature: 25℃
Cone rotation speed: 10 rpm
Measurement time: 10 minutes.

(Modulus of elasticity)
Each of the polyamide-imide resin compositions obtained in Examples 1 to 3 and Comparative Examples 1 to 3 was coated onto a substrate using a bar coater and dried to obtain a film with a thickness of 10 μm. Main drying of the membrane was then carried out at 230° C. for 2 hours. The coating film thus obtained was cut into 4 mm width pieces and used as samples for measurement.
The measurement sample was installed in a dynamic viscoelasticity measuring device "Rheogel-E4000 model" manufactured by UBM Corporation, and the elastic modulus of the polyamide-imide resin was measured. The measurement was carried out under the condition that the distance between the chucks was 20 mm, and the elastic modulus was obtained by reading the value at 35°C.

(Dielectric breakdown voltage)
Each of the polyamide-imide resin compositions obtained in Examples 1 to 3 and Comparative Examples 1 to 3 was coated onto an Al metal substrate using a bar coater and dried to obtain a film with a thickness of 10 μm. Main drying of the membrane was then carried out at 230° C. for 2 hours. The dielectric breakdown voltage of the resulting coating film was measured under the following conditions.
Test temperature: 25℃
Boosting speed: 0.5kV/sec (AC 50Hz)
Electrode dimensions: High pressure side: φ20mm ball, low pressure side: Metal plate Test atmosphere: In oil

(Measurement of aspect ratio)
Coating was performed under the following conditions using each polyamideimide resin composition (varnish) obtained in Examples 1 to 3 and Comparative Examples 1 to 3.
Nozzle diameter: φ0.29mm
Nozzle speed: 10mm/sec Discharge pressure: 0.3MPa
Next, after drying, main drying was carried out at 230° C. for 2 hours. The shape of the dried coating film was measured using a Dektak 6M surface profiler (manufactured by ULVAC, Inc.), and the aspect ratio of the coating film (=coating film thickness/coating film width) was calculated.

As can be seen from Table 1, the resin compositions of Examples 1 to 3, which are embodiments of the present invention, all have dielectric breakdown voltages of 150 kV/mm or more and dry coating film aspect ratios of 0 after dispensing. It was .05 or more. Further, the elastic modulus was within the range of 0.5 to 3.0 GPa. For these reasons, by using a resin containing the structural unit (Ia) and the structural unit (IIa) and having an Mw of 100,000 or more, a resin composition with excellent insulation properties, flexibility, and thick film forming properties can be obtained. It turns out that we can provide the following.

On the other hand, the resin composition of Comparative Example 1 used a resin with an Mw of less than 100,000, and in comparison with Examples 1 to 3, the viscosity was low and the thick film forming property was inferior. In the resin composition of Comparative Example 2, inorganic filler (silica) was added for the purpose of improving the viscosity of the resin composition of Comparative Example 1. However, in Comparative Example 2, in comparison with Examples 1 to 3, although the viscosity and aspect ratio values were comparable, the breakdown voltage was significantly lower. The resin composition of Comparative Example 3 uses a resin that contains the structural unit (Ia) but does not contain the structural unit (IIa). In comparison with Examples 1 to 3, Comparative Example 3 has a similar viscosity and aspect ratio, but has a high elastic modulus, so it is considered that the reliability of the power semiconductor device deteriorates.

From the above, the resin composition according to the present invention can be suitably used as a constituent material of power semiconductor devices where high insulation is required in some areas, and it is possible to ensure sufficient insulation. I know what will happen.

1: Lead frame 1a: Die pad 1b: Lead 2: Semiconductor element 3a, 3b, 3: Insulating film (cured film of resin composition)
4 Wire 5 Resin sealing layer

Claims (7)

(A) Contains a structural unit represented by the following formula (Ia) and a structural unit represented by the following formula (IIa); A polyamide-imide resin containing 3 to 7 mol% of the structural unit represented by the formula (IIa) and having a weight average molecular weight of 120,000 to 160,000, based on the total number of moles with the structural unit represented by the formula (IIa). (B) an organic solvent;
A resin composition having a viscosity in the range of 7,000 to 15,000 mPa·s when measured at 25° C. and 10 rpm using an E-type viscometer.

[In the formula, R ₁ to R ₄ are each independently selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 9 carbon atoms, an alkoxy group having 1 to 9 carbon atoms, and a halogen atom. It represents one or more substituents, and X is a single bond or a divalent organic group selected from the following.

(wherein R ₅ and R ₆ are each independently selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 9 carbon atoms, a trifluoromethyl group, a trichloromethyl group, and a phenyl group) It is a substituent of more than one species.)]

[In the formula, R ₇ to R ₁₀ each independently represent a hydrogen atom or a substituent, R ₁₁ and R ₁₂ each independently represent a divalent hydrocarbon group, and m is 1 or more is an integer. ] The resin composition according to claim 1 , wherein the polyamide-imide resin further includes a structural unit represented by the following formula (IIIa).

The resin composition according to claim 1 or 2 , wherein the film obtained by drying has a dielectric breakdown voltage of 150 kV/mm or more. The resin composition according to any one of claims 1 to 3 , wherein the polyamide-imide resin has a glass transition temperature of 200°C or higher. The resin composition according to any one of claims 1 to 4 , wherein the membrane obtained by drying has an elastic modulus of 0.5 to 3.0 GPa at 35°C. A semiconductor device comprising a film formed using the resin composition according to any one of claims 1 to 5 on a surface of a component. At least forming an insulating film by applying and drying the resin composition according to any one of claims 1 to 5 on the surface of a substrate on which a semiconductor element is mounted, and forming a resin sealant on the insulating film. A method of manufacturing a semiconductor device comprising forming a stop layer.

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