JP2011202139A - Adhesive composition and adhesive tape - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an adhesive composition enabling the crosslinking polymerization reaction of the thermosetting polyimide based resin composition to proceed without essentially requiring a high temperature condition, moreover enabling the crosslinking polymerization reaction to proceed sufficiently without requiring a long period of time; and to provide an adhesive tape using the same.SOLUTION: The adhesive composition which enables a crosslinking polymerization reaction to proceed sufficiently without requiring high temperature and a long period of time can be obtained by using an adhesive composition including a thermosetting polyimide based resin composition and an energy sensitive base generating agent which generates a base by a heat or energy ray. Furthermore, the adhesive tape can be obtained by using such an adhesive composition.

Description

  The present invention relates to an adhesive composition and an adhesive tape.

  Adhesive tapes are used in the manufacturing process of various industrial products, such as the process of manufacturing semiconductor chip packages.

  CSP (Chip Size Package) has been proposed as a package form that realizes high-density mounting of semiconductor chips. Among them, a package form called QFN (Quad Flat Non-Leaded Package) is small and highly integrated. In particular, it is attracting attention because it is a technology that can be easily realized.

  As a QFN manufacturing method, a manufacturing method based on a MAP (Molded Array Packaging) method in which a plurality of chips are collectively sealed has attracted attention in terms of high productivity. This manufacturing method includes a die bonding step of fixing a semiconductor chip on a die pad of a lead frame, a wire bonding step of connecting a bonding wire to the inner lead of the lead frame and the semiconductor chip on the die pad, and bonding between the inner lead and the semiconductor chip. A resin sealing step of covering the wire with a resin material. When manufacturing QFN by this method, the pressure-sensitive adhesive tape plays an extremely important role as a masking sheet tape to be affixed to the back side of the lead frame in order to smoothly perform the above steps.

  In the manufacturing method of QFN, an extremely high heat history of about 180 ° C. to 270 ° C. is usually applied in a wire bonding process or the like. For this reason, the adhesive tape is required to have excellent heat resistance. Specifically, a polyimide resin film is used as a base sheet, and the base sheet surface is made of a specific polyimide resin composition. An adhesive tape in which a layer is formed has been proposed (for example, Patent Document 1).

JP 2001-262116 A

  In order to prepare an adhesive tape using a polyimide resin composition like the adhesive tape described in Patent Document 1, the polyimide precursor resin constituting the polyimide resin composition is subjected to a crosslinking polymerization reaction by heat treatment. It becomes essential to form an adhesive layer. However, in order to proceed with this cross-linking polymerization reaction, the heat treatment needs to be performed under extremely high temperature conditions of 180 ° C. to 270 ° C., and in addition, it is performed for a relatively long time in order to sufficiently proceed with the cross-linking polymerization reaction. There was a problem that needed to be done.

  The present invention makes it possible to advance the crosslinking polymerization reaction of the thermosetting polyimide resin composition without requiring high-temperature conditions, and to sufficiently advance the crosslinking polymerization reaction without requiring a long time. It is an object of the present invention to provide a pressure-sensitive adhesive composition that can be used, and to provide a pressure-sensitive adhesive tape using such a pressure-sensitive adhesive composition.

The present invention includes [1] a thermosetting polyimide resin composition and an energy-sensitive base generator that generates a base by heat or energy rays,
[2] The energy sensitive base generator generates at least one base selected from primary amines, secondary amines, tertiary amines, and amidine compounds by heat or energy rays. [1] The pressure-sensitive adhesive composition according to
[3] The energy-sensitive base generator is heated at a temperature of 80 ° C. or higher and lower than 180 ° C., whereby at least one of a primary amine, a secondary amine, a tertiary amine, and an amidine compound is used. The pressure-sensitive adhesive composition according to the above [1], which generates a base,
[4] The thermosetting polyimide resin composition was selected from the group consisting of tetracarboxylic dianhydride represented by the following formula (1) and tetracarboxylic acid and tetracarboxylic acid derivatives represented by the following formula (2). One or more compounds (Q) and an aliphatic diamine represented by the following formula (3) are mixed and heated so that the number of moles of the compound (Q) is larger than the number of moles of the aliphatic diamine. None, polyimide (A), polyimide (A) and aromatic diamine represented by the following formula (4) are heated to react with polyimide (B), polyimide (B) and the bismaleimide compound represented by the following formula (5) And the pressure-sensitive adhesive composition according to any one of [1] to [3] above.

（Ｒ_１は４価の有機基である）

(R ₁ is a tetravalent organic group)

（Ｒ_２は４価の有機基であり、Ｙ_１〜Ｙ_４は独立した水素または炭素数１〜８の炭化水素基である）

(R ₂ is a tetravalent organic group, and Y _{1 to} Y ₄ are independent hydrogen or a hydrocarbon group having 1 to 8 carbon atoms)

（Ｒ_３は、アミノ基に脂肪族基または脂環基が直接結合している炭素数１〜２２１の２価の有機基であり、その構造の一部に芳香族基、エーテル基、その他の置換基を含んでいてもよい。）

(R ₃ is a C1-221 divalent organic group in which an aliphatic group or an alicyclic group is directly bonded to an amino group, and an aromatic group, an ether group, (It may contain a substituent.)

（Ｒ_４は、アミノ基に芳香族環が直接結合している炭素数６〜２７の２価の有機基であり、その構造の一部に脂肪族基、脂環基、その他の置換基を含んでいてもよい。）

(R ₄ is a divalent organic group having 6 to 27 carbon atoms in which an aromatic ring is directly bonded to an amino group, and an aliphatic group, an alicyclic group, and other substituents are added to a part of the structure. May be included.)

（Ｚは２価の有機基である）

(Z is a divalent organic group)

The present invention also provides [5] the pressure-sensitive adhesive composition according to any one of [1] to [4], further including an isocyanate-based crosslinking agent,
[6] The pressure-sensitive adhesive composition according to the above [5], wherein the isocyanate-based crosslinking agent has two or more isocyanate groups per molecule,
[7] The pressure-sensitive adhesive composition according to any one of [1] to [6], further including an antioxidant,
[8] The pressure-sensitive adhesive composition according to the above [7], wherein the antioxidant is a hindered phenol derivative or a benzotriazole derivative.
[9] An adhesive tape formed by forming an adhesive layer on the heat-resistant substrate sheet surface, wherein the adhesive layer is a cured product of the adhesive composition according to any one of [1] to [8]. Adhesive tape, characterized by
[10] The adhesive tape according to [9], wherein the adhesive layer has room temperature adhesiveness,
[11] The pressure-sensitive adhesive layer according to [9] or [10], wherein the pressure-sensitive adhesive layer has a glass transition temperature of less than 30 ° C. and is 1 or more in a ball tack test according to JIS Z 0237,
[12] A die bonding step for fixing the semiconductor chip on the die pad of the lead frame, a wire bonding step for connecting the bonding wire to the inner lead of the lead frame and the semiconductor chip on the die pad, and the inner lead, the semiconductor chip and the bonding wire. A pressure-sensitive adhesive tape according to any one of the above [9] to [11], which is used in a method for producing a semiconductor product comprising a resin sealing step of covering with a resin material;
[13] The adhesive according to [12], which is attached to one surface of the lead frame before the die bonding step and is peeled off from one surface of the lead frame after the resin sealing step. tape,
[14] The heat-resistant substrate sheet is also characterized by the pressure-sensitive adhesive tape according to any one of [9] to [13], wherein the weight loss rate before and after heating at 250 ° C. for 1 hour is less than 5%. .

  According to the present invention, the cross-linking polymerization reaction of the thermosetting polyimide resin composition can be allowed to proceed without requiring high-temperature conditions, and the cross-linking polymerization reaction proceeds sufficiently without taking a long time. It is possible to provide a pressure-sensitive adhesive composition that can be used, and to provide a pressure-sensitive adhesive tape using such a pressure-sensitive adhesive composition.

It is a schematic longitudinal cross-sectional view which shows one of the Examples of the adhesive tape provided with the adhesion layer which uses the adhesive composition of this invention. (A) It is a plane schematic diagram which shows typically one of the lead frames. (B) It is a partial expansion schematic diagram which shows typically the state where the portion of field S in Drawing 2 (a) was expanded, (c) Partial section which shows the AA line section in Drawing 2 (a) typically It is a schematic diagram. (A) It is process sectional drawing for demonstrating the sticking process which adhere | attaches an adhesive tape on a lead frame, (b) It is process sectional drawing for demonstrating a die bonding process, (c) A wire bonding process is demonstrated. (D) a process sectional view for explaining a resin sealing process, (e) a process sectional view for explaining a peeling process, and (f) obtained by a QFN process. It is a cross-sectional schematic diagram for demonstrating a semiconductor product.

  The pressure-sensitive adhesive composition of the present invention comprises a thermosetting polyimide resin composition and an energy sensitive base generator.

(Thermosetting polyimide resin composition)
The thermosetting polyimide resin composition (composition (K)) is produced by sequentially performing the first to third steps shown below.

  That is, the step of reacting compound (Q) with an aliphatic diamine (imidation reaction) to synthesize polyimide (A) (first step), the polyimide (A) and aromatic diamine are heated and reacted. A composition by performing a step of synthesizing polyimide (B) (second step), a step of mixing polyimide (B) and a bismaleimide compound and mixing them at a predetermined temperature (third step). (K) is manufactured.

(About the first step)
In the first step, the aliphatic diamine and the compound (Q) as described above are heated in the absence of a solvent to carry out an imidation reaction between the aliphatic diamine and the compound (Q), and polyimide is obtained as a reaction product of the imidization reaction. (A) is synthesized.

  In the imidization reaction, an acid anhydride group or a functional group of a dicarboxylic acid derivative that can be imidized is arranged at both ends of the polyimide (A), and a compound having a functional group capable of imidization ( From the viewpoint of suppressing the residual amount of Q), the compound (Q) is preferably blended and carried out so that the number of moles of the compound (Q) is larger than the number of moles of the aliphatic diamine. The compound (Q) is preferably blended at a ratio of 1 mol or more and 2 mol or less with respect to mol.

  In addition, a 1st process may be implemented by making imidation reaction of aliphatic diamine and a compound (Q) in various organic solvents. The organic solvent that can be used is not particularly limited. For example, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, N, N-dimethylformamide, dimethyl sulfoxide, hexamethylphosphoramide, tetramethylene sulfone, m -Cresol, phenol, diglyme, triglyme, tetraglyme, dioxane, γ-butyrolactone, dioxolane, cyclohexanone, cyclopentanone, etc. can be used, but N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N -It is preferable to use dimethylformamide and γ-butyrolactone alone or in combination.

  In the first step, the imidization reaction is preferably carried out under conditions of a reaction time of 1 to 12 hours and a reaction temperature of 150 to 200 ° C.

(Compound (Q))
Compound (Q) is at least one compound selected from the group consisting of tetracarboxylic dianhydrides represented by the following formula (1) and tetracarboxylic acids represented by the following formula (2) and derivatives thereof.

（Ｒ_１は４価の有機基である）

(R ₁ is a tetravalent organic group)

（Ｒ_２は４価の有機基であり、Ｙ_１〜Ｙ_４は独立して水素または炭素数１〜８の炭化水素基である。）

(R ₂ is a tetravalent organic group, and Y _{1 to} Y ₄ are independently hydrogen or a hydrocarbon group having 1 to 8 carbon atoms.)

  Examples of tetracarboxylic dianhydrides include aliphatic tetracarboxylic dianhydrides. Moreover, in order to express desired heat resistance, the aromatic tetracarboxylic dianhydride illustrated as needed can also be used.

  Examples of the aliphatic tetracarboxylic dianhydride include 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 1,2,3,4-butanetetracarboxylic dianhydride, 1,2,3,4 -Cyclobutanetetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic dianhydride, bicyclo [2.2.2] oct-7-ene-2,3,5,6-tetracarboxylic Examples thereof include acid dianhydride and dicyclohexyltetracarboxylic dianhydride. Although it does not specifically limit as what is used, Preferably, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 1,2,3,4-butanetetracarboxylic dianhydride, 2,3,4-cyclobutanetetracarboxylic dianhydride, more preferably 1,2,4,5-cyclohexanetetracarboxylic dianhydride.

  As aromatic tetracarboxylic dianhydride, pyromellitic dianhydride, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride, 2,3,3 ′, 4′-biphenyltetracarboxylic acid Dianhydride, 2,2-bis (3,4-dicarboxyphenyl) propane dianhydride, 2,2-bis (2,3-dicarboxyphenyl) propane dianhydride, 2,2-bis (3 4-dicarboxyphenyl) -1,1,1,3,3,3-hexafluoropropane dianhydride, 2,2-bis (2,3-dicarboxyphenyl) -1,1,1,3,3 , 3-hexafluoropropane dianhydride, bis (3,4-dicarboxyphenyl) sulfone dianhydride, bis (3,4-dicarboxyphenyl) ether dianhydride, bis (2,3-dicarboxyphenyl) Ether dianhydride 3,3 ′, 4,4′-benzophenone tetracarboxylic dianhydride, 2,2 ′, 3,3′-benzophenone tetracarboxylic dianhydride, 4,4 ′-(p-phenylenedioxy) diphthal Acid dianhydride, 4,4 ′-(m-phenylenedioxy) diphthalic dianhydride, ethylenetetracarboxylic dianhydride, 3-carboxymethyl-1,2,4-cyclopentanetricarboxylic dianhydride, 1,1-bis (2,3-dicarboxyphenyl) ethane dianhydride, bis (2,3-dicarboxyphenyl) methane dianhydride, bis (3,4-dicarboxyphenyl) methane dianhydride, etc. I can list them.

  Examples of tetracarboxylic acid and derivatives thereof include aliphatic tetracarboxylic acid and derivatives thereof, and aromatic tetracarboxylic acid and derivatives thereof.

  Examples of the aliphatic tetracarboxylic acid include 1,2,4,5-cyclohexanetetracarboxylic acid, 1,2,3,4-butanetetracarboxylic acid, 1,2,3,4-cyclobutanetetracarboxylic acid, 1,2 3,4-cyclopentanetetracarboxylic acid, bicyclo [2.2.2] oct-7-ene-2,3,5,6-tetracarboxylic acid, dicyclohexyltetracarboxylic acid and the like. Examples of the derivative of the aliphatic tetracarboxylic acid include esters of the above-described aliphatic tetracarboxylic acid and alcohol (having 1 to 8 carbon atoms).

  As aromatic tetracarboxylic acid, pyromellitic acid, 3,3 ′, 4,4′-biphenyltetracarboxylic acid, 2,3,3 ′, 4′-biphenyltetracarboxylic acid, 2,2-bis (3, 4-dicarboxyphenyl) propane, 2,2-bis (2,3-dicarboxyphenyl) propane, 2,2-bis (3,4-dicarboxyphenyl) -1,1,1,3,3,3 -Hexafluoropropane, 2,2-bis (2,3-dicarboxyphenyl) -1,1,1,3,3,3-hexafluoropropane, bis (3,4-dicarboxyphenyl) sulfone, bis ( 3,4-dicarboxyphenyl) ether, bis (2,3-dicarboxyphenyl) ether, 3,3 ′, 4,4′-benzophenone tetracarboxylic acid, 2,2 ′, 3,3′-benzophenone Lacarboxylic acid, 4,4 ′-(p-phenylenedioxy) diphthalic acid, 4,4 ′-(m-phenylenedioxy) diphthalic acid, ethylenetetracarboxylic acid, 3-carboxymethyl-1,2,4-cyclo Examples include pentanetricarboxylic acid, 1,1-bis (2,3-dicarboxyphenyl) ethane, bis (2,3-dicarboxyphenyl) methane, and bis (3,4-dicarboxyphenyl) methane. Examples of the aromatic tetracarboxylic acid derivative include esters of the above aromatic tetracarboxylic acid and an alcohol (having 1 to 8 carbon atoms).

(Aliphatic diamine)
The aliphatic diamine is represented by the following formula (3).

（Ｒ_３は、アミノ基に脂肪族基または脂環基が直接結合している炭素数１〜２２１の２価の有機基であり、その構造の一部に芳香族基、エーテル基、その他の置換基を含んでいてもよい。）

(R ₃ is a C1-221 divalent organic group in which an aliphatic group or an alicyclic group is directly bonded to an amino group, and an aromatic group, an ether group, (It may contain a substituent.)

  Therefore, the aliphatic diamine is a diamine having a molecular structure in which an aliphatic group or an alicyclic group is directly bonded to an amino group. The aliphatic diamine may contain an aromatic group, an ether group, or other substituents in a part of the molecular structure. Examples of the aliphatic diamine include polyoxyalkylene diamine, 4,4′-diaminodicyclohexyl methane, isophorone diamine, ethylene diamine, tetramethylene diamine, norbornane diamine, paraxylylenediamine, 1,3-bis (amino Examples include methyl) cyclohexane, 1,3-diaminocyclohexane, hexamethylenediamine, metaxylylenediamine, 4,4′-methylenebis (cyclohexylamine), bicyclohexyldiamine, and siloxane diamines. The aliphatic diamine is preferably a polyoxyalkylene diamine in order to make the cured product of the pressure-sensitive adhesive composition excellent in flexibility and tackiness.

(About the second step)
In the second step, polyimide (B) is synthesized by blending aromatic diamine with polyimide (A) and heating in the absence of solvent to carry out an imidization reaction.

  In the second step, the imidization reaction of polyimide (A) and aromatic diamine may be carried out in various organic solvents. As the organic solvent, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, N, N-dimethylformamide, dimethyl sulfoxide, hexamethylphosphoramide, tetramethylene sulfone, tetrahydrofuran, acetone and the like can be used. Further, m-cresol, phenol, diglyme, triglyme, tetraglyme, dioxane, γ-butyrolactone, dioxolane, cyclohexanone, cyclopentanone, etc. can be used, but N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide and γ-butyrolactone are preferably used alone or in combination.

  In the second step, as in the first step, the imidation reaction is preferably carried out under conditions of a reaction time of 1 to 12 hours and a reaction temperature of 150 to 200 ° C.

(Aromatic diamine)
The aromatic diamine is represented by the following formula (4).

（Ｒ_４は、アミノ基に芳香族環が直接結合している炭素数６〜２７の２価の有機基であり、その構造の一部に脂肪族基、脂環基、その他の置換基を含んでいてもよい。）

(R ₄ is a divalent organic group having 6 to 27 carbon atoms in which an aromatic ring is directly bonded to an amino group, and an aliphatic group, an alicyclic group, and other substituents are added to a part of the structure. May be included.)

  An aromatic diamine is a diamine in which an aromatic ring is directly bonded to an amino group. As aromatic diamines, 3,4′-diaminodiphenyl ether, 4,4′-diaminodiphenyl ether, 4,4′-diaminodiphenylmethane, 4,4′-diaminodiphenyl sulfone, m-phenylenediamine, p-phenylenediamine, 2 , 4-toluenediamine, diaminobenzophenone, 2,6-diaminonaphthalene, 1,5-diaminonaphthalene, 1,4-bis (4-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene, 1 , 3-bis (3-aminophenoxy) benzene, 4,4′-bis (4-aminophenoxy) biphenyl, α, α′-bis (3-aminophenyl) -1,4-diisopropylbenzene, bis [4- (4-Aminophenoxy) phenyl] sulfone, bis [4- (3-aminopheno) Xyl) phenyl] sulfone, α, α'-bis (4-aminophenyl) -1,4-diisopropylbenzene, 2,2-bis (4-aminophenoxyphenyl) propane and the like. Among these, from the viewpoint of heat resistance and adhesiveness, 3,4′-diaminodiphenyl ether, 4,4′-diaminodiphenyl ether, 4,4′-bis (4-aminophenoxy) biphenyl, 2,2-bis (4-amino) Phenoxyphenyl) propane is preferred.

(About the third step)
In the third step, the polyimide (B) synthesized in the second step and the bismaleimide compound are mixed. What is obtained by this is the composition (K). The bismaleimide compound exhibits a function as a crosslinking agent, and is blended in an amount of 0.25 mol to 4 mol with respect to 1 mol of the aliphatic diamine used for producing the polyimide (A). It is preferable to make the cured product of the pressure-sensitive adhesive composition excellent in flexibility.

(Bismaleimide compound)
The bismaleimide compound is a compound represented by the following formula (5).

（Ｚは２価の有機基である）

(Z is a divalent organic group)

  Examples of the bismaleimide compound include N, N ′-(4,4′-diphenylmethane) bismaleimide, N, N ′-(4,4′-diphenyloxy) bismaleimide, N, N ′-(4,4′- Diphenylsulfone) bismaleimide, N, N′-p-phenylene bismaleimide, N, N′-m-phenylene bismaleimide, N, N′-2,4-tolylene bismaleimide, N, N′-2,6 -Tolylene bismaleimide, N, N'-ethylene bismaleimide, N, N'-hexamethylene bismaleimide, N, N '-{4,4'-[2,2'-bis (4 ", 4 ' '' -Phenoxyphenyl) isopropylidene]} bismaleimide, N, N ′-{4,4 ′-[2,2′-bis (4 ″, 4 ′ ″-phenoxyphenyl) hexafluoroisopropylidene]} Bi Maleimide, N, N ′-[4,4′-bis (3,5-dimethylphenyl) methane] bismaleimide, N, N ′-[4,4′-bis (3,5-diethylphenyl) methane] bis Maleimide, N, N ′-[4,4 ′-(3-methyl-5-ethylphenyl) methane] bismaleimide, N, N ′-[4,4′-bis (3,5-diisopropylphenyl) methane] Bismaleimide, N, N ′-(4,4′-dicyclohexylmethane) bismaleimide, N, N′-p-xylylene bismaleimide, N, N′-m-xylylene bismaleimide, N, N ′-( 1,3-dimethylenecyclohexane) bismaleimide, N, N ′-(1,4-dimethylenecyclohexane) bismaleimide, and bismaleimide compounds include N, N ′-(4,4′-diphenylmeta ) Bismaleimide, N, N '-[4,4'-bis (3-methyl-5-ethylphenyl) methane] bismaleimide, polyphenylmethane maleimide and the like. Among these, N, N ′-(4,4′-diphenylmethane) bismaleimide, N, N ′-[4,4 ′-(3-methyl-5-ethylphenyl) methane] bismaleimide from the viewpoint of heat resistance, Polyphenylmethane maleimide is preferred.

  The pressure-sensitive adhesive composition of the present invention may further contain an isocyanate-based crosslinking agent. An isocyanate type crosslinking agent can function as a crosslinking agent which performs the crosslinking reaction of the said polyimide (B) which comprises a thermosetting polyimide resin composition.

(Isocyanate-based crosslinking agent)
The isocyanate-based crosslinking agent comprises at least one of an isocyanate compound and a blocked isocyanate compound.

  The isocyanate compound that can be selected as the isocyanate-based crosslinking agent is preferably an isocyanate compound having two or more isocyanate groups per molecule. Specific examples of the isocyanate compound include lower aliphatic polyisocyanates such as butylene diisocyanate and hexamethylene diisocyanate, alicyclic isocyanates such as cyclopentylene diisocyanate, cyclohexylene diisocyanate, and isophorone diisocyanate, and 2,4-triisocyanate. Aromatic isocyanates such as diisocyanate, 4,4′-diphenylmethane diisocyanate, xylylene diisocyanate, trimethylolpropane / tolylene diisocyanate trimer adduct (trade name Coronate L, manufactured by Nippon Polyurethane Industry Co., Ltd.), trimethylolpropane / Hexamethylene diisocyanate trimer adduct (trade name Coronate HL, manufactured by Nippon Polyurethane Industry Co., Ltd.), isocyanurate of hexamethylene diisocyanate Door body (trade name: Coronate HX, manufactured by Nippon Polyurethane Industry Co., Ltd.), and the like isocyanate adducts, such as can be exemplified. These compounds may be used alone or in combination of two or more. If the isocyanate compound has two or more isocyanate groups, the cross-linking polymerization reaction between the polyimides (B) can be effectively performed.

  The isocyanate-based cross-linking agent preferably contains an isocyanate compound having a chemical structure formed by bonding isocyanate groups to carbons at both ends of the hydrocarbon. As such an isocyanate compound, the compound shown to the compound shown to following formula (6) can be mentioned.

（Ｒ_９は、炭素数１〜１８の２価の有機基であり、その構造の一部に脂肪族基、脂環基、その他の置換基を含んでいてもよい。）

(R ₉ is a divalent organic group having 1 to 18 carbon atoms, aliphatic groups in a part of the structure, an alicyclic group, may contain other substituents.)

  The blocked isocyanate compound that can be selected as the isocyanate-based crosslinking agent is a compound having in its molecular structure an isocyanate group protected with a blocking agent. In addition, the blocked isocyanate compound may be any of the isocyanate compounds having two or more isocyanate groups per molecule, as long as at least a part of the isocyanate groups are protected by the blocking group. The compound is usually formed by protecting all isocyanate groups of the above-mentioned isocyanate compounds with a blocking agent.

  As for the blocked isocyanate compound, examples of the blocking agent include phenol, alcohol, active methylene such as dimethyl malonate, ethyl acetoacetate, and ε-caprolactam. The blocked isocyanate compound is preferably one in which an oxime compound, an active methylene compound, caprolactam, or alcohol is used as a blocking agent in terms of easy preparation of the blocked isocyanate.

  The blocked isocyanate compound generates two or more isocyanate groups per molecule when heated in a temperature range of 60 ° C. or higher and 150 ° C. or lower, and 1 when heated in a temperature range of 80 ° C. or higher and 120 ° C. or lower. It is preferable that two or more isocyanate groups are generated per molecule from the viewpoint of facilitating storage stability and curing of the pressure-sensitive adhesive composition.

  The isocyanate-based crosslinking agent may be added to the pressure-sensitive adhesive composition in an appropriate blending amount, but may be blended in the range of 1 to 30 parts by weight with respect to 100 parts by weight of the polyimide (B). In order to make the cured product of the pressure-sensitive adhesive composition excellent in flexibility, it is preferably 3 parts by weight to 20 parts by weight. If the amount of the isocyanate-based crosslinking agent is less than 1 part by weight, the cured product of the pressure-sensitive adhesive composition may have a low degree of crosslinking and heat resistance may be insufficient. If the amount of the isocyanate-based crosslinking agent exceeds 30 parts by weight, There exists a possibility that it may become an excessive crosslinking degree and the adhesiveness of the hardened | cured material of an adhesive composition may be insufficient.

(Energy sensitive base generator)
The energy sensitive base generator generates a base by heat or energy rays.

  The energy ray is a concept including light rays and ionizing radiation, the light ray is a concept including at least one of ultraviolet rays, visible rays, and infrared rays, and the ionizing radiation includes X-rays, γ rays, and the like. The concept includes radiation having energy for ionizing a substance and particle beams such as an electron beam.

  The energy-sensitive base generator is preferably one that generates at least one base selected from primary amines, secondary amines, tertiary amines, and amidine compounds by heat or energy rays. The primary amine, secondary amine, and tertiary amine are not particularly limited, but N- (isopropoxycarbonyl) -2,6-dimethylpiperidine, N- (tert-butoxycarbonyl)- Examples include 2,6-dimethylpiperidine, N- (benzyloxycarbonyl) -2,6-dimethylpiperidine, and 1,3-bis (4-aminophenoxy) benzene. The amidine-based compound comprises a compound having an amidine structure as shown in the following formula (7) and a heterocyclic compound having an amidine partial structure. Specifically, the amidine-based compound includes diazabicycloundecene, diazabicyclononene, imidazole, pyrimidine, and purine, which are heterocyclic compounds having a partial structure of amidine.

（Ｒ_５からＲ_８は、水素原子、炭素数１〜１８のアルキル基、炭素数２〜１８のアルケニル基、または炭素数６〜１２のアリール基である。また、Ｒ_５からＲ_８は、相互に連結して環状構造を形成してもよい。）

(R ₅ to R ₈ are a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, or an aryl group having 6 to 12 carbon atoms. Also, R ₅ to R ₈ are They may be connected to each other to form a ring structure.)

  As an energy sensitive base generator that generates a base by heat, a known thermal base generator can be used. As a thermal base generator that can be used in the pressure-sensitive adhesive composition, 1,8-diazabicyclo manufactured by San Apro Co., Ltd. is used. [5.4.0] Undec-7ene (DBU) (registered trademark), 1,5-diazabicyclo [4.3.0] none-5-ene (DBN), U-CAT SA102, U-CAT SA506, Specific examples include U-CAT series such as U-CAT SA810, U-CAT 5002, U-CAT 5003, and U-CAT 18X, and POLYCAT series such as POLYCAT 9, PORYCAT 12, and POLYCAT 41.

  Among energy sensitive base generators, those that generate bases by heat (thermal base generators) are those that generate bases at temperatures below 200 ° C, but bases that are at temperatures above room temperature (25 ° C) and below 200 ° C. It is preferable that it is generated, and it is more preferable that the base is generated at a temperature of 80 ° C. or higher and lower than 180 ° C. If such an energy-sensitive base generator generates a base at a temperature that is too low, the energy-sensitive base generator becomes too sensitive to the base-generating reaction, and the coating composition is obtained by dissolving the adhesive composition in a solvent. There is a risk that the stability of the product will deteriorate. If the energy sensitive base generator does not generate a base unless the temperature is too high such that the temperature exceeds 200 ° C., it serves as a catalyst for the crosslinking polymerization reaction of the thermosetting polyimide resin composition There is a risk that it will disappear.

  Among energy sensitive base generators, those that generate bases by energy rays (energy ray base generators) can be used. Examples of the energy ray base generator include oxime ester compounds and oxime ester polymers as shown in Chemical Formula 13 below.

  Examples of the energy ray base generator include quaternary ammonium salt compounds as shown in Chemical Formula 14 below.

  Examples of the energy ray base generator include acyl compounds as shown in the following chemical formula 15.

  Examples of the energy ray base generator include carbamate compounds as shown in the following chemical formulas 16 and 17.

  Moreover, as an energy beam base generator, the compound as shown in following Chemical formula 18 is mentioned, for example.

（上記（化１８）中、Ｒ^１及びＲ^２は、それぞれ独立に、水素又は１価の有機基であり、同一であっても異なっていても良い。Ｒ^１及びＲ^２は、それらが結合して環状構造を形成していても良く、ヘテロ原子の結合を含んでいても良い。但し、Ｒ^１及びＲ^２の少なくとも１つは１価の有機基である。また、化１７における、Ｒ^３、Ｒ^４、Ｒ^５及びＲ^６は、それぞれ独立に、水素、ハロゲン、水酸基、ニトロ基、ニトロソ基、メルカプト基、シリル基、シラノール基又は１価の有機基であり、同一であっても異なっていても良い。Ｒ^３、Ｒ^４、Ｒ^５及びＲ^６は、それらの２つ以上が結合して環状構造を形成していても良く、ヘテロ原子の結合を含んでいても良い。）

(In the above (Chemical Formula 18), R ¹ and R ² are each independently hydrogen or a monovalent organic group and may be the same or different. R ¹ and R ² are bonded to each other. And a ring structure may be formed, and a bond of a hetero atom may be included, provided that at least one of R ¹ and R ² is a monovalent organic group. ³ , R ⁴ , R ⁵ and R ⁶ are each independently hydrogen, halogen, hydroxyl group, nitro group, nitroso group, mercapto group, silyl group, silanol group or monovalent organic group, R ³ , R ⁴ , R ^5, and R ⁶ may be bonded to each other to form a cyclic structure or may include a heteroatom bond.

Since the energy ray base generator represented by Chemical formula 18 has the specific structure as described above, irradiation with energy rays such as ultraviolet rays results in (—CH═CH—C (═O) in (Chemical formula 18). The)-) moiety isomerizes to the cis isomer and is further cyclized by heating to produce the base (NHR ¹ R ² ). That is, the energy ray base generator represented by Chemical formula 18 can generate a primary amine, a secondary amine, or an amidine compound as a base according to the structure.

  The energy ray base generators shown in Chemical formula 13 to Chemical formula 18 can be used singly or in combination.

(Preparation of adhesive composition)
The pressure-sensitive adhesive composition of the present invention can be prepared by mixing a thermosetting polyimide resin composition and an energy sensitive base generator. In the pressure-sensitive adhesive composition, the amount (% by weight) of the energy sensitive base generator is from 0.1% by weight to 35% by weight, more preferably from 1% by weight to 10% by weight. If the blending amount of the energy sensitive base generator in the pressure-sensitive adhesive composition is less than 0.1% by weight, the blending amount is too small and the curing of the pressure-sensitive adhesive composition may be insufficient, and the pressure-sensitive adhesive composition If the amount of the energy-sensitive base generator exceeds 35% by weight, the amount of the energy-sensitive base generator may be so large that low-molecular components such as the energy-sensitive base generator may bleed from the cured product. In this respect, when the energy sensitive base generator is in the preferable blending amount range, it is possible to obtain an effect that a cured product having desired heat resistance can be obtained when the pressure-sensitive adhesive composition is cured. .

  The pressure-sensitive adhesive composition of the present invention may further contain an antioxidant and other additives.

(Antioxidant)
The antioxidant is not particularly limited as long as it has heat resistance. Specific examples of the antioxidant include hindered amine derivatives, hindered phenol derivatives, phosphorus compounds, sulfur compounds, hydroxyl compounds, triazole derivatives, benzotriazole derivatives, and triazine derivatives. Preference is given to using phenol derivatives and / or benzotriazole derivatives. When such an antioxidant is contained in the pressure-sensitive adhesive composition, a high-temperature heat history exceeding 180 ° C. is applied to the pressure-sensitive adhesive tape formed with the pressure-sensitive adhesive layer made of this pressure-sensitive adhesive composition on the base sheet. It is possible to effectively suppress the problem of deterioration of the pressure-sensitive adhesive layer that is particularly likely to occur.

  In the pressure-sensitive adhesive composition, the antioxidant is blended in such a proportion that the blending amount of the antioxidant with respect to 100 parts by weight of the thermosetting polyimide resin composition is in the range of 0.1 to 10 parts by weight. It is preferable that an agent is contained. If the blending amount of the antioxidant is less than 0.1 parts by weight, the ability to suppress the oxidative deterioration of the adhesive layer in the adhesive tape using the adhesive composition is insufficient, and the blending amount of the antioxidant is 10 parts by weight. Exceeding this is not preferable because an adhesive residue due to bleeding of the antioxidant from the adhesive layer occurs.

(Other additives)
The pressure-sensitive adhesive composition further includes various additives such as a plasticizer, a filler, and an antistatic agent as long as it does not impair the use and function of the pressure-sensitive adhesive tape provided with the pressure-sensitive adhesive layer using the pressure-sensitive adhesive composition. It may be.

(State of pressure-sensitive adhesive composition)
The pressure-sensitive adhesive composition includes a composition (K) composed of a mixture of a compound having a function of a crosslinking agent such as a bismaleimide compound and polyimide (B), a mixture of an energy ray-sensitive base generator, and other In addition to the mixture in which the additive is added and dissolved in a solvent at a predetermined temperature (adhesive composition liquid), each solid component constituting the adhesive composition liquid (non-solvent component) ) In the form of a mixture (solid content mixture).

  It is preferable that the amount of the solvent is an amount that provides a viscosity that enables casting into a film using the solution. The temperature at which the solids such as the polyimide (B) and the bismaleimide compound are dissolved in the solvent effectively dissolves the bismaleimide compound in the solvent to obtain a uniform solution and the composition (K) is cured. In order to suppress this, 0 ° C to 80 ° C is preferable, and 20 ° C to 60 ° C is more preferable. Further, the solvent has a boiling point that is equal to or higher than the melting temperature and lower than the curing temperature of the thermosetting polyimide resin composition. Therefore, the boiling point of the solvent is preferably in the range of 60 ° C. or more and less than 200 ° C., more preferably in the range of 60 ° C. or more and 180 ° C. or less, and in the range of more than 80 ° C. and 180 ° C. or less. More preferably it is.

  Examples of the solvent include 1,3-dioxolane, N, N-dimethylacetamide (DMAc), N-methyl-2-pyrrolidone, N, N-dimethylformamide, hexamethylphosphoramide and other amide solvents, methyl ethyl ketone, acetone Ketone solvents such as 1, cyclic solvents such as 1,4-dioxane and tetrahydrofuran, and acetonitrile. In particular, it is preferable to use an amide solvent such as N, N-dimethylacetamide, N-methyl-2-pyrrolidone, N, N-dimethylformamide, hexamethylphosphoramide alone or in combination.

  Next, the adhesive tape which formed the adhesive layer using the adhesive composition of this invention is described. This adhesive tape can be used for various purposes. In particular, a case will be described in which the adhesive tape is an adhesive tape (semiconductor product assembly tape) used when performing each process of manufacturing a semiconductor product such as QFN.

(Adhesive tape 1)
The pressure-sensitive adhesive tape 1 is formed by forming a pressure-sensitive adhesive layer 3 on the heat-resistant substrate sheet 2 (FIG. 1).

(Heat resistant base sheet 2)
The heat-resistant substrate sheet 2 is made of a sheet material having a melting point exceeding the highest processing temperature (process maximum processing temperature) when performing each process (semiconductor product manufacturing process) for manufacturing a semiconductor product such as QFN.

  The sheet material used as the material of the heat-resistant substrate sheet 2 is preferably a flexible film material in order to easily carry out the attaching process to be attached to the lead frame and the peeling process to be removed from the lead frame. However, it is preferable that the film material having flexibility does not cause excessive expansion in a temperature range when performing each step of manufacturing a semiconductor product. Examples of such a film material include film materials made of polyimide, polyamide, polyether sulfone, polyphenylene sulfide, polyether ketone, polyether ether ketone, triacetyl cellulose, polyether imide, polyethylene naphthalate, and the like. In view of excellent heat resistance, polyimide is particularly preferable.

  The thickness of the heat resistant substrate sheet 2 is preferably in the range of 5 μm to 200 μm. The heat-resistant substrate sheet 2 has a weight reduction rate of less than 5% before and after heating at 250 ° C. for 1 hour, and the glass transition point is preferably 150 ° C. or higher, and more preferably 180 ° C. or higher. The heat resistant base sheet 2 preferably has a thermal expansion coefficient at 150 to 250 ° C. of 5 to 50 ppm / ° C., more preferably 10 to 30 ppm / ° C. When the heat-resistant substrate sheet 2 has a low reduction rate when heated at a high temperature before and after heating for 1 hour at 250 ° C. and the weight reduction rate is less than 5%, the heat-resistant substrate sheet 2 is resistant to heat during high-temperature heating when performing a semiconductor product manufacturing process. Decomposition of the conductive base sheet 2 is suppressed. If the glass transition point of the heat resistant base sheet 2 is 150 ° C. or higher, softening of the heat resistant base sheet 2 can be suppressed during high-temperature heating in the semiconductor product manufacturing process. Moreover, the thermal expansion coefficient of the heat resistant base sheet 2 from 150 ° C. to 250 ° C. is 5 to 50 ppm / ° C., so that the heat shrinkage of the pressure-sensitive adhesive tape 1 accompanying cooling after heating is performed in the semiconductor product manufacturing process. It is possible to suppress the possibility of warping of the semiconductor product.

(Adhesive layer 3)
The pressure-sensitive adhesive layer 3 is a layer made of a cured product of the pressure-sensitive adhesive composition of the present invention.

  The adhesive layer 3 has normal temperature adhesiveness. In the present specification, “having room temperature adhesiveness” indicates that it can be attached to an adherend by a method of applying JIS Z 0237 at room temperature (23 ° C. to 30 ° C.). Further, “possible to paste” means that the peel strength of the adhesive layer 3 with respect to SUS (stainless steel) specified in JIS Z 0237 is 0.001 (N / 25 mm) or more. The peel strength of the adhesive layer 3 is preferably 0.01 (N / 25 mm) or more.

  It is more preferable that the adhesive layer 3 has an adhesiveness to a desired adherend of 1 or more (ball number is 1 or more) in a ball tack test based on JIS Z 0237. If the pressure-sensitive adhesive layer 3 has a pressure-sensitive adhesiveness of 1 or more according to the ball tack test method, the room-temperature pressure-sensitive adhesive property is more reliably exhibited.

  The ball tack test based on JIS Z 0237 used for the measurement of adhesiveness is performed as follows.

  First, a test body obtained by cutting the adhesive tape 1 into a width of 25 mm to 50 mm and a length of 100 mm or more is prepared. Next, the test body is set on the ball tack test machine so that the adhesive surface becomes the surface and the inclination angle of the adhesive surface becomes 30 degrees. Furthermore, a steel ball is rolled so that it may pass through the area | region in a predetermined measurement surface among the adhesion surfaces of the test body set to the ball tack tester. At this time, the length of the measurement surface on which the steel ball is rolled is 100 mm. The steel ball having a diameter of 1/32 inch to 1 inch is used. And the ball number of the largest diameter is found among the steel balls which stop in the area | region of a measurement surface when these steel balls are rolled. The ball number is obtained by multiplying the diameter of the steel ball by 32. If the ball number is 1 or more, the adhesive surface has adhesiveness, and the larger the ball number, the stronger the adhesive surface.

  The thickness of the adhesive layer 3 is preferably in the range of 3 μm or more and 50 μm or less, more preferably in the range of 5 μm or more and 20 μm or less. When the thickness of the pressure-sensitive adhesive layer 3 is 3 μm or less, the adhesive strength is insufficient, which is not preferable in terms of lowering the sticking property to the adherend, and when the thickness is 50 μm or more, after the heat history of the adherend to which the adhesive tape is attached. Since there is a possibility that adhesive residue may be generated on the adherend when the adhesive tape is peeled from the adherend, it is not preferable.

  The adhesive layer 3 preferably has a glass transition temperature of less than 30 ° C. When the glass transition temperature is less than 30 ° C., the adhesive layer 3 more reliably has adhesiveness at room temperature (23 ° C. to 30 ° C.).

  The glass transition temperature is measured by a method (DMA method) based on the peak top value of loss tangent (tan δ). Loss tangent is measured by the value of loss modulus / storage modulus. The loss elastic modulus and storage elastic modulus are applied to a layer structure made of a thermosetting polyimide resin composition at a certain frequency, and the stress when the force is applied is measured using a dynamic viscoelasticity measuring device. It is measured by measuring.

(Manufacture of adhesive tape 1)
The said adhesive tape 1 is manufactured as follows.

  First, a case where the pressure-sensitive adhesive composition contains an energy sensitive base generator that generates a base by receiving heat (first case) will be described. In this case, the pressure-sensitive adhesive composition liquid obtained by adding the pressure-sensitive adhesive composition to the solvent is applied onto the surface of the heat-resistant substrate sheet 2 to form a coating film. The coating method of the pressure-sensitive adhesive composition liquid may appropriately employ a known coating method such as a direct gravure coating method, a gravure reverse coating method, a micro gravure coating method, a phanten coating method, a dipping method, a comma coating method, or a die coating method. it can.

  Next, the heat resistant substrate sheet 2 on which the coating film is formed is placed in a predetermined temperature atmosphere for a predetermined time, whereby the coating film is heated (heating process). The heating temperature in the heating step is selected to be a temperature that is equal to or higher than the boiling point of the solvent and satisfies a temperature range in which a base can be generated from the energy sensitive base generator. Specifically, the heating step is performed at a temperature of 80 to 200 ° C, preferably at a temperature of 100 to 150 ° C. The heating time may be 1 to 15 minutes, preferably 3 to 10 minutes. As a heating method, a conventionally known heating method may be appropriately employed. In the heating step, the solvent is distilled off and the coating film is dried. Furthermore, in this heating step, the polyimide (B) and the bismaleimide compound constituting the thermosetting polyimide resin composition contained in the coating film undergo a crosslinking polymerization reaction. The coating film is cured by the progress of the crosslinking polymerization reaction. At this time, the coating film is cured to form a cured product of the pressure-sensitive adhesive composition, which forms the pressure-sensitive adhesive layer 3. In this way, the adhesive tape 1 is manufactured. In addition, when the isocyanate type crosslinking agent is added to the adhesive composition, in this heating step, the polyimide (B) and the bismaleimide compound constituting the thermosetting polyimide resin composition contained in the coating film are In addition to the crosslinking polymerization reaction, a crosslinking polymerization reaction between the polyimide (B) and the isocyanate-based crosslinking agent may also occur.

  In manufacturing the pressure-sensitive adhesive tape 1, an energy ray irradiation step may be performed after the heating step. In this case, the cross-linking polymerization reaction proceeds more efficiently and sufficiently, and a pressure-sensitive adhesive tape in which a pressure-sensitive adhesive layer is sufficiently cured is obtained, and the heat resistance of the pressure-sensitive adhesive tape is more efficiently improved. Can be improved.

The energy beam irradiation process is a process in which a predetermined energy beam is irradiated for a predetermined time toward the coating film. Energy beam irradiation step, under the conditions of an irradiation intensity 50~1000mJ / cm ² of energy rays, preferably may be made carried out under conditions of 100 to 500 mJ / cm ^2. As the energy beam irradiation method, a conventionally known method may be appropriately adopted. For example, in the case of irradiating ultraviolet rays, a general-purpose ultraviolet lamp may be used as a light source to irradiate ultraviolet rays toward the coating film.

  When the pressure-sensitive adhesive composition contains an energy-sensitive base generator that generates a base by receiving energy rays (second case), the pressure-sensitive adhesive composition adheres to the surface of the heat-resistant substrate sheet 2 as in the first case. After applying the agent composition, a heating step is performed to dry the coating film. Then, a predetermined energy ray is irradiated for a predetermined time toward the coating film. The energy beam irradiation is performed by the same method and conditions as in the energy beam irradiation step described above. In this way, the adhesive tape 1 is manufactured.

  In addition to the first and second cases, the pressure-sensitive adhesive tape 1 includes an energy-sensitive base generator that generates a base by receiving at least one of heat and energy rays (third case). ) And an energy sensitive base generator that generates a base by receiving heat and an energy sensitive base generator that generates a base by receiving energy rays (fourth case). In the third case, the energy beam irradiation process or the heating process described above may be performed, and in the fourth case, the energy beam irradiation process and the heating process may be performed.

  In addition, when both processes of a heating process and an energy ray irradiation process are implemented, both processes may be implemented separately and may be implemented simultaneously.

  Conventionally, the heating process for advancing the cross-linking polymerization reaction of the thermosetting polyimide resin composition is performed under a high temperature atmosphere of 180 to 250 ° C. under a long time condition of a heating time of 30 to 90 minutes. It was necessary to In this regard, by producing a pressure-sensitive adhesive tape using the pressure-sensitive adhesive composition of the present invention, there is no need for the cross-linking polymerization reaction under a high-temperature atmosphere and a long time condition as in the conventional heating step, and the cross-linking polymerization reaction Can be carried out in a relatively low temperature atmosphere, and the cross-linking polymerization reaction can proceed sufficiently efficiently under short-time conditions, and an adhesive layer can be formed efficiently. Therefore, by producing a pressure-sensitive adhesive tape using the pressure-sensitive adhesive composition of the present invention, it is possible to suppress the possibility that the production cost of the pressure-sensitive adhesive tape will increase, and the thermosetting polyimide resin composition has insufficient cross-linking polymerization reaction and heat. The possibility that the uncured product of the curable polyimide resin composition remains can also be suppressed.

(Use of adhesive tape 1)
The adhesive tape 1 is used as a semiconductor product assembling tape used in a semiconductor product manufacturing process (QFN process) when the semiconductor product package form is QFN.

  The QFN process includes a step of attaching the adhesive tape 1 to a lead frame (sticking step), a step of mounting a semiconductor chip on the lead frame (die bonding step), and a step of connecting the lead portion of the lead frame and the semiconductor chip with a bonding wire. (Wire bonding process), process of sealing the semiconductor chip on the surface of the lead frame with resin (resin sealing process), process of removing the adhesive tape 1 on the back of the lead frame (peeling process), process of dividing the lead frame (cutting) Step).

(Attaching process)
First, a lead frame 10 as illustrated in FIG. 2A is prepared. The lead frame 10 shown in this example includes a frame portion 30 and a package region forming portion 31 surrounded by the frame portion 30. The package region forming unit 31 is partitioned into a plurality of unit regions 11. Each unit region 11 is formed in an orderly manner. In the lead frame 10, the package region forming portion 31 on the lead frame 10 is partitioned into vertical and horizontal matrix patterns in plan view, and is partitioned as shown in FIGS. 2 (a) and 2 (c). The area of each part forms a unit area 11. FIG. 2C is a partial cross-sectional schematic diagram schematically showing a vertical cross section taken along line AA in FIG.

  In the lead frame 10, as shown in FIG. 2B, a predetermined package pattern forming portion 32 is formed in the unit region 11 in which die pads on which individual QFN semiconductor chips are arranged are formed. Specifically, a package pattern forming portion 32 corresponding to the QFN standard is formed for each unit region 11. The lead frame 10 is made of a metal such as copper, for example, and the thickness of the lead frame 10 is generally 50 to 300 μm. FIG. 2B is a partially enlarged schematic view schematically showing an enlarged portion of the region S in FIG.

  In the example of FIG. 2B, the package pattern forming unit 32 formed in the unit region 11 of the lead frame 10 forms a rectangular die pad 12 on which the semiconductor chip is mounted in the center of the unit region 11. The comb-shaped lead portion 13 is formed around the die pad 12 with the tip thereof directed toward the four side periphery of the die pad 12, and the gap portion 14 is formed between the die pad 12 and the lead portion 13. The four support parts 33 which support are formed.

  In the sticking step, the adhesive tape 1 is disposed so that the surface of the adhesive layer 3 abuts on the back side of the lead frame 10 and is pressed against the lead frame 10, and the adhesive tape 1 is applied to the surface of the lead frame 10 per surface. Affixed to the back surface (FIG. 3A). The back surface of the lead frame 10 indicates the back surface of the die pad 12, that is, the surface that is the non-contact surface of the semiconductor chip.

  The adhesive tape 1 is attached to the back surface of the lead frame 10 over a region including at least the region of the package region forming portion 31 and further to the region outside the periphery thereof, and is attached to the portion of the lead frame 10 that is sealed with resin. Affixed to the outside of the corresponding area.

(Die bonding process)
After the attaching step, as shown in FIG. 3B, the semiconductor chip 15 is placed on the surface (indicated by reference numeral 12a in FIG. 3) of the die pad 12 on the exposed surface side (surface side) of the lead frame 10, and the fixing material 16 Glue through. Thereby, the semiconductor chip 15 is mounted on the die pad 12. An adhesive such as an epoxy silver paste (a silver paste containing an epoxy resin as a resin component) is used for the fixing material 16.

  This die bonding step is performed at an ambient temperature of 150 ° C. to 180 ° C.

(Wire bonding process)
After the die bonding process, the semiconductor chip 15 and the lead portion 13 of the lead frame 10 are connected by the bonding wire 17 so as to be electrically energized (FIG. 3C).

  This wire bonding step is performed at an ambient temperature of 180 ° C. to 250 ° C.

(Resin sealing process)
After the wire bonding step, a resin layer 18 is formed by pouring resin so as to cover the entire surface of the lead frame 10 on which the semiconductor chip 15 connected with the bonding wire 17 is mounted. At this time, a state in which the semiconductor chip 15 connected to the bonding wire 17 is confined in the resin layer 18 is formed, and the semiconductor chip 15 and the bonding wire 17 are protected by the resin, and the semiconductor chip 15 and the lead portion 13 are connected. Sealing is performed in a state of being connected via the bonding wire 17 (FIG. 3D). Examples of the resin used for the sealing include an epoxy resin.

  Specifically, in the sealing step, the resin layer is usually molded in the mold by setting the lead frame 10 in a mold having a predetermined shape and pouring molten resin. In this molding, the resin is heated to a temperature of about 170 to 180 ° C., and the resin layer is molded at this temperature.

(Peeling process)
After the resin sealing step, the adhesive tape 1 adhered to the back surface of the lead frame 10 is removed (FIG. 3 (e)).

  Finally, the lead frame 10 is divided into package units (examples of division positions are indicated by K1, K2, K3, and K4 in FIG. 3E) (cut). And QFN 20 as shown in FIG. 3 (f) is manufactured. Cutting can be realized, for example, by cutting the resin layer 18 and the lead frame 10 with a cutting blade such as a dicer.

  In the description of the lead frame, the case where the unit areas 11 are separated from each other as shown in FIG. 2C is taken as an example, but the present invention is not limited to such an example, and the adjacent unit areas 11 It may be bordered. In that case, the division positions K1 and K2 shown in FIG. 3E may overlap each other, and the division positions K3 and K4 may also overlap.

  Thus, the pressure-sensitive adhesive tape 1 obtained using the pressure-sensitive adhesive composition of the present invention is bonded to the back side of the lead frame before the semiconductor chip is mounted and connected, and on the die pad of the lead frame. The semiconductor chip mounted on is sealed after being sealed with resin. Then, after the adhesive tape 1 is peeled from the back surface of the lead frame, the semiconductor product is cut into a predetermined size.

  The pressure-sensitive adhesive tape 1 includes a base material sheet 2 made of a polyimide resin film and an adhesive layer 3 made of a cross-linked polymerization cured product of a polyimide resin composition formed on the surface of the base material sheet 2. The adhesive layer 3 hardly deteriorates even if each step of the QFN process is performed in the high temperature atmosphere as described above, and can be suitably used in the QFN process.

(Other uses)
In the above description, the case where the adhesive tape 1 is a semiconductor product assembly tape used when a semiconductor product is manufactured by the QFN process has been described as an example. However, the adhesive tape 1 is limited to that used for the QFN process. It is a semiconductor product assembling tape widely used in a package process configured to seal a resin with a chip fixed to a die pad, such as a SON process and a DFN (Dual Flat Non-Leaded Package) process. There may be. Further, the adhesive tape 1 is used as a tape used for forming an adhesive layer of a final product in addition to a use as a semiconductor assembly tape used only for a necessary process in the middle of a packaging process. But it is adaptable.

  In obtaining the pressure-sensitive adhesive composition of the present invention, a thermosetting polyimide resin composition was prepared.

  In order to prepare a thermosetting polyimide resin composition, a polyimide (A) was prepared as follows, and a polyimide (B) was further prepared.

<Synthesis of polyimide (A, B)>
1,2,4,5-cyclohexanetetracarboxylic dianhydride 20.35 g (0.090 mol), polyoxypropylenediamine (manufactured by Mitsui Chemicals Fine Co., Ltd., Jeffamine D2000) 118.81 g (0.060 mol) N-methyl-2-pyrrolidone (91.50 g) was added under a nitrogen stream, heated to 200 ° C. and subjected to an imidization reaction for 3 hours, and the produced water was separated using a Dean-Stark apparatus. After the reaction, it was confirmed that there was no distillation of water, and the reaction product (polyimide (A)) was obtained by cooling to room temperature (23 ° C.). Whether or not polyimide (A) is produced can be determined by confirming the IR spectrum and confirming the characteristic absorption of the imide ring of ν (C═O) 1770 and 1706 cm ⁻¹ . Next, 12.4 g (0.060 mol) of 4,4′-diaminodiphenyl ether and 9.74 g of N-methyl-2-pyrrolidone are added to the polyimide (A), and the mixture is heated to 200 ° C. and imidized for 3 hours. The reaction was carried out and the produced water was separated using a Dean-Stark apparatus. After the imidation reaction, it was confirmed that the distillation of water stopped, the reaction product solution was allowed to cool to room temperature, and a reaction product (polyimide (B)) was obtained in the reaction product solution. Whether or not polyimide (B) is produced is confirmed from the IR spectrum.

<Preparation of thermosetting polyimide resin composition (P)>
The thermosetting polyimide resin composition (P) for forming the adhesive layer is prepared by mixing N, N ′-(4,4′-diphenylmethane) bismaleimide as a crosslinking agent with polyimide (B) under a nitrogen stream. Obtained by.

<Preparation of energy sensitive base generator>
As energy sensitive base generators, the following base generators A1 to A7 (base generation temperatures between 80 ° C. and 180 ° C.) were prepared.
Base generator A1: Thermal base generator (manufactured by Sun Apro, U-CAT 18X)
Base generator A2: Thermal base generator (manufactured by Sun Apro, U-CAT 5002)
Base generator A3: Thermal base generator (manufactured by Sun Apro Co., Ltd., U-CAT SA810)
Base generator A4: Thermal base generator (manufactured by Sun Apro, U-CAT SA506)
Base generator A5: Energy beam base generator (DNCDP)
Base generator A6: Energy beam base generator (compound shown in the following chemical formula 19)
Base generator A7: Thermal base generator (manufactured by San Apro, U-CAT 5002) and energy beam base generator (DNCDP) (combination ratio is U-CAT 5002: DNCDP = 1 (parts by weight): 1 (Weight part))

  The base generator A1 generates a tertiary amine by heating, and the base generators A2, A3, and A4 all generate amidine as a base by heating. The base generator A5 generates secondary amines as bases by irradiation with ultraviolet rays (365 nm) as energy rays. The base generator A6 generates a primary amine as a base by irradiation with ultraviolet rays (365 nm) as energy rays. The above-mentioned DNCDP represents N-{[(4,5-dimethoxy-2-nitrobenzyl) oxy] carbonyl} -2,6-dimethylpiperidine.

<Preparation of antioxidant>
Antioxidants B1 to B3 shown below were prepared as antioxidants.
Antioxidant B1: Hindered phenol-based antioxidant (Ciba Japan Co., Ltd., IRGANOX 1010)
Antioxidant B2: Hindered phenol-based antioxidant (Ciba Japan Co., Ltd., IRGANOX 1098)
Antioxidant B3: A combination of hindered phenolic antioxidant (Ciba Japan Co., Ltd., IRGANOX1010) and 1,2,3-benzotriazole (mixing ratio is hindered phenolic antioxidant: 1,2, 3-benzotriazole = 2 (parts by weight): 1 (parts by weight))

Examples 1 to 7
Using polyimide (B) and a crosslinking agent constituting the thermosetting polyimide resin composition and an energy sensitive base generator appropriately selected as shown in Table 1, these are mixed in the following blending amounts. Thus, a mixture (CA1 to CA7 in the ascending order of the example numbers) as the pressure-sensitive adhesive composition was prepared.

<Amount of each component of the adhesive composition of CA1 to CA7>
Polyimide (B): 100 (parts by weight)
Cross-linking agent: 15 (parts by weight)
Energy sensitive base generator: 1 (parts by weight)

  A cured product was prepared based on each of the obtained pressure-sensitive adhesive compositions, and the glass transition temperature of the cured product was specified.

<Hardened product made of pressure-sensitive adhesive composition>
In preparing the cured product comprising the pressure-sensitive adhesive composition, the following composition liquid was prepared. The composition liquid was a mixed liquid of N, N′-dimethylacetamide (DMAc) and 1,3-dioxolane (the mixing ratio of the mixed liquid was DMAc: 1,3-dioxolane = 30%: 70% in volume ratio) Is used to stir the pressure-sensitive adhesive composition at room temperature for 1 hour so that the solid content concentration (% by weight) is 25%, and is completely dissolved by stirring for 1 hour. I got it. This composition liquid was cured at 200 ° C. for 30 minutes to obtain a cured product made of a thermosetting polyimide resin composition. For each cured product using the pressure-sensitive adhesive composition (CA1 to CA7), the glass transition temperature of the cured product was measured based on the peak top value of loss tangent (tan δ) (based on the DMA method). The glass transition temperature of each of the cured products using the pressure-sensitive adhesive composition (CA1 to CA7) is -23 ° C for the cured product using CA1, -30 ° C for the cured product using CA2, and curing using CA3. -27 ° C for cured products, -27 ° C for cured products using CA4, -25 ° C for cured products using CA5, -26 ° C for cured products using CA6, and -26 ° C for cured products using CA7. there were.

Examples 8 to 16
Using the polyimide (B) and the crosslinking agent constituting the thermosetting polyimide resin composition, and an energy sensitive base generator and an antioxidant appropriately selected as shown in Table 1, these are blended in the following amounts. Thus, a mixture (CA8 to CA16 in the ascending order of the example numbers) was prepared as the pressure-sensitive adhesive composition.

<Amount of each component of the adhesive composition of CA8 to CA16>
Polyimide (B): 100 (parts by weight)
Cross-linking agent: 15 (parts by weight)
Energy sensitive base generator: 1 (parts by weight)
Antioxidant: 3 (parts by weight)

Comparative Preparation Example 1
The mixture (CB1) which is an adhesive composition was prepared by using the polyimide (B) and crosslinking agent which comprise the said thermosetting polyimide resin composition, and mixing these by the following compounding quantity.

<The amount of each component of the pressure-sensitive adhesive composition of CB1>
Polyimide (B): 100 (parts by weight)
Cross-linking agent: 15 (parts by weight)

Comparative Preparation Examples 2 and 3
By using the polyimide (B) and the crosslinking agent constituting the thermosetting polyimide resin composition, and an antioxidant appropriately selected as shown in Table 1, these are mixed in the following blending amounts, A mixture (CB2, CB3) as an adhesive composition was prepared.

<The amount of each component of the pressure-sensitive adhesive composition of CB2 and CB3>
Polyimide (B): 100 (parts by weight)
Cross-linking agent: 15 (parts by weight)
Antioxidant: 3 (parts by weight)

表１中「−」は、添加されなかったことを示す。

In Table 1, “-” indicates that no addition was made.

Examples 17 to 19
An adhesive tape was prepared using the adhesive composition CA1.

<Preparation of adhesive composition liquid>
Adhesive composition CA1 (100 parts by weight) as shown in Table 2 was used so that the thermosetting polyimide resin composition (P) was diluted so that the solid content concentration (wt%) was 25%. A pressure-sensitive adhesive composition liquid was prepared by mixing with a solvent for preparing a composition liquid (solvent M), stirring at room temperature for 1 hour and completely dissolving. In the present invention, the concept of the pressure-sensitive adhesive composition includes a pressure-sensitive adhesive composition liquid, and the pressure-sensitive adhesive composition liquid corresponds to one form of the pressure-sensitive adhesive composition, but for convenience, the wording of the pressure-sensitive adhesive composition liquid is used. To do.

As the solvent M, a solvent having the following composition was used.
Composition of solvent M: combined use of DMAc and 1,3-dioxolane (mixing ratio is volume ratio (%), DMAc: 1,3-dioxolane = 30: 70)

<Preparation of adhesive tape>
Using an adhesive composition liquid, this was dried on one side of a polyimide film (manufactured by Toray DuPont Co., Ltd., Kapton 100V) (thickness 25 μm) (weight reduction rate before and after heating at 250 ° C. for 1 hour is less than 1%). Applying one side using a baker type applicator so that the subsequent thickness becomes 5 μm to produce a coating film, proceeding with the crosslinking polymerization reaction of the thermosetting polyimide resin composition contained in the coating film (crosslinking polymerization step), By using the coating film as an adhesive layer, an adhesive tape (semiconductor product assembling tape) was obtained. For each of Examples 17 to 19, the cross-linking polymerization process was performed under the conditions shown in Table 2. In Examples 17 to 19, the crosslinking polymerization step is a step of heating the polyimide film on which the coating film is formed (heating step). Table 2 shows the heating time and heating temperature in the heating step. Thus, when a crosslinking polymerization process is comprised with a heating process, the implementation of this heating process uses a high temperature tank (Etsumoto Kasei Co., Ltd. product, Etak high temperature tank HT320). In Table 2, “ND” indicates that data has not been acquired. In addition, “ND” in Tables 3 and 4 to be described later also indicates that data has not been acquired.

  Whether or not the coating film was cured when the cross-linking polymerization process was performed was evaluated as follows. The results of these evaluations are as shown in Table 2.

(Curing coating film)
Evaluation of the presence or absence of hardening of a coating film was performed by the following film peeling tests.

(Film peeling test)
A film material (300 mm × 210 mm) made of polyolefin resin (Toray Industries, Ltd., Trefan BO40-2500) as a test film is pasted on the coating film surface using a hand roller at room temperature. Immediately after pasting, the test film is peeled off from the coated film surface. At this time, whether the coating film on the polyimide film remained on the test film side (whether cohesive failure occurred) was visually observed.

(Evaluation of coating film curing)
For the evaluation of the presence or absence of curing of the coating film, when the coating film does not remain on the test film side (no adhesive residue), that is, when the occurrence of cohesive failure is not observed when the test film is peeled off, the coating film Was judged to be sufficient, and was evaluated as “◯” (good). Cohesive failure is not observed when the test film is peeled off, but the coating film is sufficiently cured when fine irregularities are observed on the surface of the coated film after peeling (the coated surface is rough). It was judged that this was not possible, and was evaluated as “△” (somewhat poor). When the occurrence of cohesive failure was observed when the test film was peeled off, the coating film was judged to be insufficiently cured and evaluated as “x” (defective).

Example 20
Similarly to Example 17, a pressure-sensitive adhesive composition liquid was obtained using the pressure-sensitive adhesive composition CA1 and a solvent, and a coating film of the pressure-sensitive adhesive composition liquid was formed on the polyimide film surface. Next, a cross-linking polymerization process was performed to obtain an adhesive tape. Conditions as shown in Table 2 were adopted as the conditions for carrying out the crosslinking polymerization process. In Example 20, the cross-linking polymerization step is composed of a heating step and a step of irradiating the polyimide film on which the coating film is formed with an energy ray (energy ray irradiation step). The heating process was carried out using a high-temperature tank (Etsuk Kasei Co., Ltd., Etak high-temperature tank HT320) as in Example 17.

  In the energy ray irradiation step, the polyimide film on which the coating film was formed was irradiated with ultraviolet rays. An ultraviolet irradiation device (manufactured by Fusion UV Systems, VPS / I600 (UV irradiation device with a conveyor)) was used for ultraviolet irradiation, and an H bulb was used as a lamp in this ultraviolet irradiation device. Irradiation conditions were a lamp output of 60% and a conveyor speed of 10 m / min Using a UV irradiation device, a process in which the coating film was irradiated with UV while the polyimide film on which the coating film was formed was placed on the conveyor and transferred. When this step is performed once, the coating film is irradiated with ultraviolet rays equivalent to 100 mJ. When the coating film is irradiated with ultraviolet rays of 500 mJ, the transfer irradiation step is performed five times. Repeatedly implemented.

  In addition, when a crosslinking polymerization process is comprised by a heating process and an energy-beam irradiation process in this way, an energy-beam irradiation process is implemented after a heating process.

  Whether or not the coating film was cured when the cross-linking polymerization process was performed was evaluated in the same manner as in Example 17. The results of these evaluations are as shown in Table 2.

Examples 21, 23, 25
As shown in Table 2, except that the pressure-sensitive adhesive compositions CA2 to CA4 were used to prepare pressure-sensitive adhesive compositions and the conditions for the crosslinking polymerization process as shown in Table 2 were adopted, the same as in Example 17, The pressure-sensitive adhesive tape was prepared and evaluated whether or not the coating film was cured. The results are as shown in Table 2.

Reference examples 1, 2, 3, 4
As shown in Table 2, except that the pressure-sensitive adhesive composition CA5, CA6 was used to prepare a pressure-sensitive adhesive composition liquid and the conditions for the crosslinking polymerization process as shown in Table 2 were adopted, the same as in Example 17, The pressure-sensitive adhesive tape was prepared and evaluated whether or not the coating film was cured. The results are as shown in Table 2. In Reference Examples 1 and 3, an adhesive tape was obtained, but in Reference Examples 2 and 4, the coating film was not sufficiently cured and an adhesive layer was not formed, and an adhesive tape was not obtained.

Examples 22, 24, 26, 27, 28, 29
A pressure-sensitive adhesive composition liquid was prepared using pressure-sensitive adhesive compositions CA2 to CA7 as shown in Table 2, and the same conditions as in Example 20 were adopted except that the conditions for carrying out the crosslinking polymerization process as shown in Table 2 were adopted. While obtaining the adhesive tape, it was evaluated whether or not the coating film was cured. The results are as shown in Table 2.

Examples 30 to 34, 37 to 39, 41 to 43, 45, 47, 49
As shown in Table 3, except that the pressure-sensitive adhesive compositions CA8 to CA13 were used to prepare pressure-sensitive adhesive composition liquids and the implementation conditions of the crosslinking polymerization process as shown in Table 3 were adopted, the same as in Example 17, The pressure-sensitive adhesive tape was prepared and evaluated whether or not the coating film was cured. The results are as shown in Table 3.

Reference examples 5, 6, 7, 8
As shown in Table 3, the pressure-sensitive adhesive composition CA14, CA15 was used to prepare a pressure-sensitive adhesive composition liquid, and the same conditions as in Reference Example 1 were adopted except that the conditions for carrying out the crosslinking polymerization process as shown in Table 3 were adopted. The pressure-sensitive adhesive tape was prepared, and whether or not the coating film was cured and the state of the pressure-sensitive adhesive layer were evaluated. The results are as shown in Table 3. In Reference Examples 5 and 7, an adhesive tape was obtained, but in Reference Examples 6 and 8, the coating film was not sufficiently cured and an adhesive layer was not formed, and an adhesive tape was not obtained.

Examples 35, 36, 40, 44, 46, 48, 50 to 53
A pressure-sensitive adhesive composition liquid was prepared using pressure-sensitive adhesive compositions CA8 to CA16 as shown in Table 3, and the same conditions as in Example 20 were adopted except that the conditions for carrying out the crosslinking polymerization process as shown in Table 3 were adopted. While obtaining the adhesive tape, it was evaluated whether or not the coating film was cured. The results are as shown in Table 3.

Reference Examples 9 to 11
As shown in Table 4, adhesive composition liquids were prepared using adhesive compositions CB1, CB2, and CB3, and the same conditions as in Reference Example 1 were adopted except that the conditions for carrying out the crosslinking polymerization process as shown in Table 4 were adopted. Then, an adhesive tape was prepared, and it was evaluated whether or not the coating film was cured. The results are as shown in Table 4.

Comparative Examples 1, 2, 4, 5, 7, 8
As shown in Table 4, except that the pressure-sensitive adhesive compositions CB1 to CB3 were used to prepare pressure-sensitive adhesive composition liquids and the conditions for the crosslinking polymerization process as shown in Table 4 were adopted, the same as in Example 17, The pressure-sensitive adhesive tape was prepared and evaluated whether or not the coating film was cured. The results are as shown in Table 4.

Comparative Examples 3, 6, 9
A pressure-sensitive adhesive composition liquid was prepared using pressure-sensitive adhesive compositions CB1 to CB3 as shown in Table 4, and the same conditions as in Example 20 were adopted except that the conditions for the crosslinking polymerization process as shown in Table 4 were adopted. The pressure-sensitive adhesive tape was prepared, and whether or not the coating film was cured and the state of the pressure-sensitive adhesive layer were evaluated. The results are as shown in Table 4.

  Using the adhesive tapes obtained in Examples 17 to 20, 22, 24, 26 to 53 and Reference Examples 1, 5, 9 to 11, an adhesive test was performed for each to measure the adhesiveness of the adhesive layer. Further, a peel test was carried out to confirm the presence or absence of adhesive residue, and the adhesive strength was measured. The results are shown in Tables 5-7.

(Adhesion test)
The tack test was performed by a ball tack test according to JIS Z 0237.

  First, a test body was prepared by cutting the obtained adhesive tape into a width of 25 mm and a length of 100 mm. Next, the test body was set on a ball tack tester (manufactured by Tester Sangyo Co., Ltd.) so that the adhesive surface becomes the surface (the inclination angle of the adhesive surface is 30 °). Further, in a 23 ° C. atmosphere, the steel ball is rolled so as to pass through the measurement surface region of the adhesive layer surface of the test body set in the ball tack tester (the length of the measurement surface is 100 mm). At this time, a steel ball having a diameter of 1/32 inch to 1 inch was used. And the value of the ball number of the largest diameter was specified among the steel balls which stop in the area | region of a measurement surface when rolling these steel balls (Tables 5 to 7). The ball number is obtained by multiplying the diameter of the steel ball by 32. In Tables 5 to 7, each numerical value in the ball tack test column indicates a ball number value.

(Peel test)
The peel test was realized by performing an adhesive strength measurement method in accordance with JIS Z 0237. As the adhesive strength measurement method, the following initial adhesive strength measurement and post-heating adhesive strength measurement were performed.

(Initial adhesive strength measurement)
The obtained adhesive tape was cut into a width of 25 mm × 150 mm and attached to SUS304 with a 2 kg roller at room temperature so that the application area was 25 mm × 100 mm to obtain a test specimen. The test specimen is stored for 1 hour at room temperature (storage process). After the storage process, the test specimen is set in a tensile tester (manufactured by A & D Co., Ltd. (TENSILON RTF-1150-H)). The tape is peeled off in the 180 ° direction at a pulling speed of 300 mm / min (peeling treatment), and the adhesive strength (N / 25 mm) is measured by measuring the force required to peel the adhesive tape from the specimen during the peeling treatment. Were measured (Tables 5 to 7).

(Measurement of adhesive strength after heating)
Adhesive strength measurement after heating was carried out using the same method as the initial adhesive strength measurement, except that the test specimen was heated in place of the storage process (test specimen heat treatment). Adhesive strength (N / 25 mm) Was measured. However, when the pressure-sensitive adhesive tape obtained in Examples 17 to 20, 22, 24, 26 to 29, and Reference Example 1 was used, the specimen heat treatment was performed under conditions of a temperature of 200 ° C. and a heating time of 30 minutes. It was. When the adhesive tapes obtained in Examples 30 to 53 and Reference Examples 5 and 9 to 11 were used, the test piece heat treatment was performed at a temperature of 200 ° C. × heating time of 30 min, a temperature of 250 ° C. × heating time of 30 min. It was carried out under two conditions. In the measurement of the adhesive strength after heating, it was further visually confirmed whether or not an adhesive residue was generated on the surface of the adherend during the peeling treatment (Tables 5 to 7). In each table of Table 5 to Table 7, in the peel test column, the numerical value indicates the adhesive strength (N / 25 mm), “Yes” indicates that adhesive residue is observed, and “No” indicates adhesive residue. Indicates that was not recognized.

  As the adherend, a stainless steel (SUS) material (SUS304) was used for both the initial adhesive strength measurement and the post-heating adhesive strength measurement.

  In the peel test, both the initial adhesive strength measurement and the post-heating adhesive strength measurement were performed in an oxygen-existing atmosphere.

  From the results of the adhesive test and the peel test, it can be seen that the adhesive tape is hardly deteriorated with little adhesive residue on the edge of the affixed surface even at a high temperature heating history of 200 ° C. Furthermore, from the results of these tests, the adhesive tape having the adhesive layer to which the antioxidant was added produced almost no adhesive residue at the edge of the pasting surface even at a high temperature heating history of 250 ° C. It can also be seen that it is difficult to deteriorate.

  A wire bonding test was carried out using the adhesive tapes obtained in Examples 17, 20, 22, 24, 26 to 30, 36, 40, 44, 46, 48, 50 to 53 and Reference Examples 9 to 11, respectively. The yield of the wire bonding process in the semiconductor product assembly process was measured, and a resin protrusion test was performed. The results are shown in Tables 8 to 10.

(Wire bonding test)
Adhesive tape is affixed to the back of the lead frame (QFN lead frame (Cu lead frame) length 200 mm x width 50 mm), and bonded to the semiconductor chip using epoxy phenol-based silver paste as an adhesive on the die pad, 180 ° C The semiconductor chip was mounted on the die pad by carrying out the curing process of the silver paste for 90 minutes in the atmosphere. Next, wire bonding was performed. In the wire bonding, one end of one wire is connected to one place in the chip region on the die pad (first bonding (1st)), and the other end is connected to one place on the lead portion (second bonding (2nd) )) And one set, and this process is performed by repeating the number of sets corresponding to the number of connection points in the die pad region. In the wire bonding test, 4 wires in the vertical direction (with a wire length of less than 2 mm) and 4 wires in the horizontal direction (with a wire length of less than 2 mm) on the part facing the lead portion of one chip on the die pad, a total of 5 layers. 40 points of wire bonding were performed. Therefore, 40 sets of the first bonding and the second bonding were repeated. At this time, the arrival status was confirmed.

  For wire bonding, a wire bonder (HW27U-HF (Panasonic Factory Solutions Co., Ltd.)) was used, and the bonding was performed under the following bonding conditions.

(Bonding conditions)
・ Torch level: 0.999mm
Bond level: (1st) 5.5826 mm, (2nd) 5.826 mm
Search speed: (1st) 6, (2nd) 6
-Loop height: Nonset, rev-0.180 mm
・ Loop mode: STD B
・ Tail length: 0.699mm
・ Track correction: 0.000ms
US (ultrasonic) oscillation time: (1st) 15 ms, (2nd) 10 ms
・ US power: (1st) 55 bits, (2nd) 150 bits
Bond load: (1st) 40 g, (2nd) 120 g
・ Bonding temperature: 200 ℃

(Resin protrusion test)
Subsequent to the wire bonding test, a test for confirming the protrusion of the resin was performed. In the resin protrusion test, after the end of wire bonding, an epoxy mold resin was used, and after sealing with the resin under an atmosphere of 175 ° C. for 5 minutes, the adhesive tape was peeled off at room temperature. This was carried out by confirming whether or not the protrusion of the resin from the frame was observed during the peeling process. The results are shown in Tables 8 to 10.

Comparative Example 10
A wire bonding test and a resin protrusion test were performed in the same manner as in Example 17 except that a commercially available tape (manufactured by Nitto Denko Corporation, TRM-6250L) was used instead of the adhesive tape of Example 17. The results are shown in Table 10. As a result of the wire bonding test, 9 unattached places were confirmed. Of the 9 locations, 3 locations were unattached in the first bonding, 5 locations were unattached in the second bonding, and 1 location was unattached in both the first bonding and the second bonding. Further, as a result of the resin protrusion confirmation test, it was confirmed that the resin protruded.

  Tables 5 to 10 confirm that the pressure-sensitive adhesive tape prepared with the pressure-sensitive adhesive composition of the present invention is effective as a semiconductor product assembling tape.

Examples 54 to 57
In the same manner as in Example 1, polyimide (B) constituting the thermosetting polyimide resin composition and N, N ′-(4,4′-diphenylmethane) bismaleimide as a crosslinking agent were prepared, and polyimide (B ) And N, N ′-(4,4′-diphenylmethane) bismaleimide, the energy sensitive base generator selected in Example 1, and mixing them in the following blending amounts, A barrel mixture was prepared. In this mixture, as an isocyanate-based crosslinking agent, isocyanate compound G1-1 for Example 54, isocyanate compound G1-2 for Example 55, blocked isocyanate compound G2-1 for Example 56, and Example For 57, pressure-sensitive adhesive compositions CC1 to CC4 were prepared by adding 15 parts by weight of blocked isocyanate compound G2-2 (Table 11). In addition, each isocyanate type crosslinking agent is shown below.

<The amount of each component of the adhesive composition of CC1 to CC4>
Polyimide (B): 100 (parts by weight)
Energy sensitive base generator: 1 (parts by weight)
Cross-linking agent N, N ′-(4,4′-diphenylmethane) bismaleimide: 5 (parts by weight)
Isocyanate-based crosslinking agent: 15 (parts by weight)

  The contents of the isocyanate compounds G1-1 and G1-2 blocked isocyanate compounds G2-1 and G2-2 prepared as isocyanate crosslinking agents are as follows.

<Isocyanate-based crosslinking agent>
Isocyanate compound (G1-1): Coronate L (manufactured by Nippon Polyurethane Industry Co., Ltd.)
Isocyanate compound (G1-1): TD-75 (manufactured by Soken Chemical Co., Ltd.)
Block isocyanate compound (G2-1): Duranate MF-K60X (Asahi Kasei Chemicals)
Block isocyanate compound (G2-2): Coronate 2507 (manufactured by Nippon Polyurethane Industry Co., Ltd.)

  The blocked isocyanate compound generates an isocyanate group at a temperature of 80 to 130 ° C.

  Here, compared with CA of Example 1, in CC1 to CC4, although the compounding quantity of bismaleimide is reduced, when an isocyanate type crosslinking agent is added, the compounding quantity of bismaleimide is reduced. This is because the polyimide (B) can be cured. In the pressure-sensitive adhesive composition, when 100 parts by weight of the polyimide (B) is blended with the isocyanate-based crosslinking agent in the range of 1 to 30 parts by weight, the bismaleimide is blended at about 5 parts by weight. It's okay.

Example 58
In the same manner as in Example 2, polyimide (B) and N, N ′-(4,4′-diphenylmethane) bismaleimide as a crosslinking agent were prepared in the same manner as the pressure-sensitive adhesive composition CA2, and polyimide (B) and N, N, N ′-(4,4′-diphenylmethane) bismaleimide and the energy sensitive base generator selected in Example 2 were mixed in the same amount as the adhesive composition CC1 of Example 54 to prepare a mixture, To this mixture, 15 parts by weight of a blocked isocyanate compound G2-1 was further added as the following isocyanate-based crosslinking agent to prepare an adhesive composition CC5 (Table 11).

Example 59
In the same manner as in Example 8, polyimide (B) and N, N ′-(4,4′-diphenylmethane) bismaleimide as a crosslinking agent were prepared in the same manner as the pressure-sensitive adhesive composition CA8, and polyimide (B) and N, N, N ′-(4,4′-diphenylmethane) bismaleimide, the energy sensitive base generator selected in Example 8 was mixed in the same amount as the adhesive composition CC1 of Example 54 to prepare a mixture, To this mixture, 15 parts by weight of a blocked isocyanate compound G2-1 was further added as the following isocyanate-based crosslinking agent to prepare an adhesive composition CC6 (Table 11).

Examples 60-65
Example 60, 61, 62, and 64 were carried out except that the pressure-sensitive adhesive compositions CC1 to CC6 were used as shown in Table 11 for each example and the conditions for carrying out the crosslinking polymerization process as shown in Table 12 were adopted. In the same manner as in Example 17, Examples 63 and 65 were prepared in the same manner as in Example 20 to prepare adhesive tapes, respectively, and evaluated whether or not the coating film was cured. The results are as shown in Table 12.

  Using the adhesive tapes obtained in Examples 60, 64, and 65, Examples 60 and 64 were treated in the same manner as in Example 17, and Example 65 was treated in the same manner as in Example 30. Was carried out to measure the adhesiveness of the adhesive layer, and further a peeling test was carried out to confirm the presence or absence of adhesive residue, the adhesive strength was measured, and a wire bonding test and a resin protrusion confirmation test were conducted. The results are shown in Tables 13 to 15.

DESCRIPTION OF SYMBOLS 1 Adhesive tape 2 Heat resistant base material sheet 3 Adhesive layer 10 Lead frame 11 Unit area | region 12 Die pad 13 Lead part 14 Gap part 15 Semiconductor chip 16 Fixing material 17 Bonding wire 18 Resin layer 20 QFN
30 Frame portion 31 Package region forming portion 32 Package pattern forming portion 33 Support portion

Claims (14)

  A pressure-sensitive adhesive composition comprising a thermosetting polyimide resin composition and an energy-sensitive base generator that generates a base by heat or energy rays.   The energy-sensitive base generator generates at least one base of a primary amine, a secondary amine, a tertiary amine, and an amidine compound by heat or energy rays. Adhesive composition.   The energy sensitive base generator generates at least one base selected from primary amine, secondary amine, tertiary amine and amidine compound by heating at a temperature of 80 ° C. or higher and lower than 180 ° C. The pressure-sensitive adhesive composition according to claim 1. The thermosetting polyimide resin composition is one or more selected from the group consisting of tetracarboxylic dianhydrides represented by the following formula (1) and tetracarboxylic acids and tetracarboxylic acid derivatives represented by the following formula (2): The compound (Q) and the aliphatic diamine represented by the following formula (3) are mixed so that the number of moles of the compound (Q) is larger than the number of moles of the aliphatic diamine, and heated to react with the polyimide (A ), None, polyimide (A) and an aromatic diamine represented by the following formula (4) are heated to react with each other, polyimide (B), and polyimide (B) and a bismaleimide compound represented by the following formula (5) are mixed. The pressure-sensitive adhesive composition according to any one of claims 1 to 3.

(R ₁ is a tetravalent organic group)

(R ₂ is a tetravalent organic group, and Y _{1 to} Y ₄ are independent hydrogen or a hydrocarbon group having 1 to 8 carbon atoms)

(R ₃ is a C1-221 divalent organic group in which an aliphatic group or an alicyclic group is directly bonded to an amino group, and an aromatic group, an ether group, (It may contain a substituent.)

(R ₄ is a divalent organic group having 6 to 27 carbon atoms in which an aromatic ring is directly bonded to an amino group. May be included.)

(Z is a divalent organic group)   The pressure-sensitive adhesive composition according to any one of claims 1 to 4, further comprising an isocyanate-based crosslinking agent.   The pressure-sensitive adhesive composition according to claim 5, wherein the isocyanate-based crosslinking agent has two or more isocyanate groups per molecule.   The pressure-sensitive adhesive composition according to claim 1, further comprising an antioxidant.   The pressure-sensitive adhesive composition according to claim 7, wherein the antioxidant is a hindered phenol derivative or a benzotriazole derivative.   It is an adhesive tape formed by forming an adhesive layer on the heat-resistant substrate sheet surface, and the adhesive layer is a cured product of the adhesive composition according to any one of claims 1 to 8. Adhesive tape.   The pressure-sensitive adhesive tape according to claim 9, wherein the pressure-sensitive adhesive layer has room temperature adhesion.   11. The adhesive tape according to claim 9, wherein the adhesive layer has a glass transition temperature of less than 30 ° C. and is 1 or more in a ball tack test in accordance with JIS Z 0237.   A die bonding process for fixing the semiconductor chip on the die pad of the lead frame, a wire bonding process for connecting the bonding wire to the inner lead of the lead frame and the semiconductor chip on the die pad, and the inner lead, the semiconductor chip and the bonding wire with a resin material The pressure-sensitive adhesive tape according to any one of claims 9 to 11, wherein the pressure-sensitive adhesive tape is used in a method for producing a semiconductor product comprising a resin sealing step for covering.   The pressure-sensitive adhesive tape according to claim 12, wherein the pressure-sensitive adhesive tape is attached to one surface of the lead frame before the die bonding step and is peeled off from one surface of the lead frame after the resin sealing step.   The pressure-sensitive adhesive tape according to any one of claims 9 to 13, wherein the heat-resistant substrate sheet has a weight reduction rate of less than 5% before and after heating at 250 ° C for 1 hour.

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