JP5643536B2 - Thermally conductive adhesive resin composition, laminate comprising the same, and semiconductor device - Google Patents

Description

  The present invention relates to a thermally conductive adhesive resin composition, a laminate including the same, and a semiconductor device.

  As a means for imparting thermal conductivity to a resin composition, it is generally known to add an inorganic filler having high heat dissipation. For example, Patent Document 1 discloses a heat dissipating sheet containing an imide elastomer and a heat dissipating filler, Patent Document 2 discloses a laminate having an insulating layer containing polyimide and a heat conductive filler, and Patent Document 3 discloses polyimide or polyphenylene. An electrical insulating material including an organic material such as oxide and an inorganic filler is described.

JP 2009-215480 A JP 2009-96192 A Japanese Patent Laid-Open No. 6-188530

  However, the insulating materials of Patent Documents 1 and 2 have insufficient thermal conductivity. Moreover, since the insulating material of patent document 1 contains the imide-type elastomer which has an amide bond in a molecule | numerator, its hygroscopic property and hydrolysis resistance were low. Although the insulating material of Patent Document 3 has good thermal conductivity, it has a relatively low adhesiveness because it contains a relatively large amount of inorganic filler.

  In particular, in a resin composition containing a resin and an inorganic filler, if the compatibility between the resin and the inorganic filler is low, a portion that is not covered with the resin, that is, a void (void) is generated around the inorganic filler. Specifically, the resin cannot enter the gap formed in the filler aggregate, and the gap becomes a void. When voids are generated, gaps made of gas lower the thermal conductivity, and the density of the filler also decreases, so that the thermal conductivity is lowered. For this reason, in order to obtain a certain thermal conductivity, since a large amount of fillers must be added, the adhesiveness tends to be impaired. That is, there is a demand for a resin composition having good thermal conductivity and adhesiveness, and preferably having better heat resistance.

  The present invention has been made in view of such circumstances, and it is possible to achieve both improvement in thermal conductivity and improvement in adhesion of a resin composition containing a polyimide resin and an inorganic filler, preferably further heat resistance. It aims at realizing improvement in performance.

  By increasing the compatibility between the polyimide resin and the inorganic filler, the present inventors cover the periphery of the inorganic filler with no gap and suppress voids, thereby obtaining high thermal conductivity even with a small inorganic filler content. I found out that

  And in order to improve the compatibility of a polyimide resin and an inorganic filler, it discovered that the carbonyl group (different from the carbonyl group which comprises an imide ring) should just be introduce | transduced into polyimide resin more than fixed. On the other hand, if too much carbonyl group is introduced, the carbonyl group may react with other functional groups to make it difficult to form a varnish, or the heat resistance may be lowered.

  Therefore, by introducing the carbonyl group into the polyimide and further introducing another rigid skeleton, while suppressing the above-mentioned problems, it is possible to achieve both heat conductivity and adhesiveness, and also maintain heat resistance. I found out that it could be realized. The present invention has been made based on such findings.

1st of this invention is related with a heat conductive adhesive resin composition.
[1] A thermally conductive adhesive resin composition comprising a polyimide resin (A) and 25 to 60% by volume of an inorganic filler (B), wherein the polyimide resin (A) is composed of tetracarboxylic dianhydride and An aromatic tetracarboxylic dianhydride (α1) having a carbonyl group other than the carbonyl group constituting the imide ring out of the total of the tetracarboxylic dianhydride and the diamine, including a polycondensation unit of diamine, and a carbonyl The total proportion of the aromatic diamine having a group (β1) is 1.0 mol% or more and 29.0 mol% or less, and the carbonyl group other than the carbonyl group constituting the imide ring is a keto group or an oxycarbonyl group. , A dioxycarbonyl group or an amide group (wherein the nitrogen atom contained in the amide group is the nitrogen atom constituting the imide ring),
The tetracarboxylic dianhydride constituting the polyimide resin (A) further includes a tetracarboxylic dianhydride represented by the formula (1) together with the aromatic tetracarboxylic dianhydride (α1), or The heat conductive adhesive resin composition in which the diamine which comprises the said polyimide resin (A) further contains the diamine represented by Formula (2) with the said aromatic diamine ((beta) 1).
[M in Formula (1) and n in Formula (2) are each an integer of 0 or more]
[2] A thermally conductive adhesive resin composition comprising a polyimide resin (A) and 25 to 60% by volume of an inorganic filler (B), wherein the polyimide resin (A) is composed of tetracarboxylic dianhydride and An aliphatic tetracarboxylic dianhydride (α2) having a carbonyl group other than a carbonyl group constituting an imide ring out of the total of the tetracarboxylic dianhydride and the diamine, including a polycondensation unit with a diamine; The total ratio of the carbonyl group-containing aliphatic diamine (β2) is 1.0 mol% or more and 50.0 mol% or less, and the carbonyl group other than the carbonyl group constituting the imide ring is a keto group, an oxy group Constituting a carbonyl group, a dioxycarbonyl group or an amide group (wherein the nitrogen atom contained in the amide group is the nitrogen atom constituting the imide ring),
The tetracarboxylic dianhydride constituting the polyimide resin (A) further includes a tetracarboxylic dianhydride represented by the formula (1) together with the aliphatic tetracarboxylic dianhydride (α2), or The heat conductive adhesive resin composition in which the diamine which comprises the said polyimide resin (A) further contains the diamine represented by Formula (2) with the said aliphatic diamine ((beta) 2).
[M in Formula (1) and n in Formula (2) are each an integer of 0 or more]
[3] A thermally conductive adhesive resin composition comprising a polyimide resin (A) and 25 to 60% by volume of an inorganic filler (B), wherein the polyimide resin (A) comprises tetracarboxylic dianhydride, A tetracarboxylic dianhydride (α) having a carbonyl group other than a carbonyl group constituting an imide ring out of the total of the tetracarboxylic dianhydride and the diamine, including a polycondensation unit with a diamine, and a carbonyl group The total proportion of the diamine (β) having a diamine group is 1.0 mol% or more and 50.0 mol% or less (of which an aromatic tetracarboxylic dianhydride having a carbonyl group other than the carbonyl group constituting the imide ring) (Α1) and the aromatic diamine having a carbonyl group (β1) in a total ratio of 1.0 mol% or more and 29.0 mol% or less) and the imide ring constituting the imide ring. Boniru carbonyl groups other than groups are keto group, oxycarbonyl group, di-oxycarbonyl group or an amide group (provided that the nitrogen atom contained in the amide group, a is a nitrogen atom constituting the imide ring) constitute,
Whether the tetracarboxylic dianhydride constituting the polyimide (A) further includes a tetracarboxylic dianhydride represented by the formula (1) together with the tetracarboxylic dianhydride (α) having the carbonyl group, Or the heat conductive adhesive resin composition in which the diamine which comprises the said polyimide resin (A) further contains the diamine represented by Formula (2) with the diamine ((beta)) which has the said carbonyl group.
[M in Formula (1) and n in Formula (2) are each an integer of 0 or more]
[4] The tetracarboxylic dianhydride (α2) represented by the formula (1) is a tetracarboxylic dianhydride represented by the formulas (1A) to (1C), and the formula (2) The diamine (β2) represented is the thermally conductive adhesive resin composition according to any one of [1] to [3], which is a diamine represented by the formula (2A).
[5] The thermally conductive adhesive resin composition according to any one of [1] to [4], wherein the molecular terminal of the polyimide resin (A) is an amino group.
[6] The thermally conductive adhesive resin composition according to any one of [1] to [5], wherein the inorganic filler (B) is boron nitride.
[7] The heat conductive adhesive resin composition according to any one of [1] to [6], wherein the heat conductivity is 5.0 W / m · K or more.

The 2nd of this invention is related with the laminated body containing a heat conductive adhesive resin composition, and a semiconductor device.
[8] A laminate comprising a resin layer comprising the thermally conductive adhesive resin composition according to any one of [1] to [7], and a conductor layer disposed on one or both surfaces of the resin layer.
[9] A resin layer comprising the thermally conductive adhesive resin composition according to any one of [1] to [7], a conductor layer disposed on one or both sides of the resin layer and having a predetermined circuit pattern; A semiconductor device comprising: a semiconductor element joined to the conductor layer.
[10] The semiconductor device according to [9], wherein the semiconductor element is a power semiconductor element having an output capacity of 100 VA or more.
[11] The semiconductor device according to [9] or [10], wherein the resin layer is disposed on a heat sink.

  According to the present invention, it is possible to provide a resin composition having good thermal conductivity and adhesion, preferably a resin composition having even better heat resistance.

It is a schematic diagram which shows an example of a structure of the semiconductor device in this invention. It is a photograph of the polyimide film cross section in an Example / comparative example.

1. Resin Composition The adhesive resin composition of the present invention contains a polyimide resin (A) and an inorganic filler (B), and may contain other optional components as necessary.

  The polyimide resin (A) is a polyimide or a precursor thereof containing a unit obtained by polycondensation reaction of tetracarboxylic dianhydride and diamine.

  The polyimide resin (A) has a keto group (C—C (═O) —C), an oxycarbonyl group (C (═O) —O), a dioxycarbonyl group (O—C (═O) in the molecule. -O) or an amide group (C (= O) -N) is included, which includes a “carbonyl group other than a carbonyl group constituting an imide ring” or more. However, in this invention, the nitrogen atom contained in an amide group shall be the nitrogen atom which comprises an imide ring.

  Since these carbonyl groups (carbonyl groups other than the carbonyl group constituting the imide ring) easily interact with the functional group (for example, hydroxyl group) on the surface of the inorganic filler (B), the polyimide resin (A) and the inorganic filler (B This is because the compatibility of) can be increased. If the compatibility between the polyimide resin (A) and the inorganic filler (B) is high, the polyimide resin covers the periphery of the inorganic filler (B) without any gaps, so that voids are hardly generated.

  In the polyimide having such a structure, at least a part of the tetracarboxylic dianhydride to be reacted is "tetracarboxylic dianhydride (α) having a carbonyl group other than a carbonyl group constituting the imide ring", Alternatively, at least a part of the diamine to be reacted can be obtained as “a diamine having a carbonyl group (β)”.

  “A tetracarboxylic dianhydride (α) having a carbonyl group other than a carbonyl group constituting an imide ring” is an aromatic tetracarboxylic dianhydride (α1) depending on the type of skeleton into which the carbonyl group is introduced. And aliphatic tetracarboxylic dianhydride (α2).

  That is, the aromatic tetracarboxylic dianhydride (α1) having a carbonyl group is a carbonyl group (C (═O)), an oxycarbonyl group (C (═O) —O) or a dioxycarbonyl group (O—C). Whether both ends of (= O) -O) are bonded to an aromatic group; the carbonyl carbon atom of an amide group (C (= O) -N) is bonded to an aromatic group. The aliphatic tetracarboxylic dianhydride (α2) having a carbonyl group is a carbonyl group (C (═O)), an oxycarbonyl group (C (═O) —O) or a dioxycarbonyl group (O—C (═ Whether at least one of the terminals of O) -O) is bonded to an aliphatic group; the carbonyl carbon atom of the amide group (C (= O) -N) is bonded to an aliphatic group.

  In the aromatic tetracarboxylic dianhydride (α1) having a carbonyl group, an aromatic group bonded to both ends of the carbonyl group, oxycarbonyl group or dioxycarbonyl group; or an aromatic group bonded to the carbonyl carbon atom of the amide group The group is not particularly limited, and is a monocyclic aromatic group, a condensed polycyclic aromatic group, a non-condensed polycyclic aromatic group in which aromatic groups are connected to each other directly or by a bridging member, and the like. A monocyclic aromatic group such as a phenyl group is preferred.

  Examples of aromatic tetracarboxylic dianhydrides (α1) having a carbonyl group include 2,2 ′, 3,3′-benzophenone tetracarboxylic dianhydride, 3,3 ′, 4,4′-benzophenone tetra Carboxylic dianhydrides, 2,3 ′, 3,4-benzophenone tetracarboxylic dianhydride, phenylenebis (trimellitic acid monoester) dianhydride (TAHQ) and the like are included.

  In an aliphatic tetracarboxylic dianhydride (α2) having a carbonyl group, an aliphatic group bonded to at least one terminal of a carbonyl group, an oxycarbonyl group or a dioxycarbonyl group; or bonded to a carbonyl carbon atom of an amide group The aliphatic group is not particularly limited, but a chain aliphatic group, a monocyclic aliphatic group, a condensed polycyclic aliphatic group, or a non-condensed group in which a cyclic aliphatic group is connected to each other directly or by a crosslinking member. A polycyclic aliphatic group, preferably a chain aliphatic group having 1 to 10 carbon atoms. The aromatic group bonded to one end of the carbonyl group, oxycarbonyl group or dioxycarbonyl group is defined in the same manner as the aromatic group described above.

  Examples of the aliphatic tetracarboxylic dianhydride (α2) having a carbonyl group include ethylene glycol bistrimellitic dianhydride.

  These tetracarboxylic dianhydrides can be used alone or in combination of two or more.

  The “diamine having a carbonyl group (β)” is also classified into an aromatic diamine (β1) and an aliphatic diamine (β2) depending on the type of skeleton into which the carbonyl group is introduced.

  The aromatic diamine having a carbonyl group (β1) is a carbonyl group (C (═O)), an oxycarbonyl group (C (═O) —O) or a dioxycarbonyl group (O—C (═O) —O). Are both bonded to the aromatic group; the carbonyl carbon atom of the amide group (C (═O) —N) is bonded to the aromatic group. The aliphatic diamine (β2) having a carbonyl group is a carbonyl group (C (═O)), an oxycarbonyl group (C (═O) —O) or a dioxycarbonyl group (O—C (═O) —O). Or at least one of the terminals of the amide group is bonded to an aliphatic group; the carbonyl carbon atom of the amide group (C (═O) —N) is bonded to the aliphatic group.

  In the aromatic diamine having a carbonyl group (β1), the aromatic group bonded to both ends of the carbonyl group, the oxycarbonyl group or the dioxycarbonyl group; or the aromatic group bonded to the carbonyl carbon atom of the amide group is as described above. Defined similarly to the aromatic group in the aromatic tetracarboxylic dianhydride (α1). Examples of the aromatic diamine having a carbonyl group (β1) include 3,3′-diaminobenzophenone, 3,4′-diaminobenzophenone, 4,4′-diaminobenzophenone, 4,4′-bis [4- (4 -Amino-α, α-dimethylbenzyl) phenoxy] benzophenone, bis [4- (3-aminophenoxy) phenyl] ketone, bis [4- (4-aminophenoxy) phenyl] ketone, 1,4-diaminoanthraquinone, 1 , 5-diaminoanthraquinone, 2,6-diaminoanthraquinone, and the like.

In the aliphatic diamine having a carbonyl group (β2), an aliphatic group bonded to at least one terminal of the carbonyl group, oxycarbonyl group or dioxycarbonyl group; or an aliphatic group bonded to the carbonyl carbon atom of the amide group, Defined similarly to the aliphatic group in the above-mentioned aliphatic tetracarboxylic dianhydride (α2). Examples of the aliphatic diamine (β2) having a carbonyl group include malonamide, 2-phenylmalonamide, and a diamine represented by the following general formula (3). In General formula (3), n represents the integer of 1-50, Preferably the integer of 10-20 is represented. On the other hand, X represents an alkylene group having 1 to 10 carbon atoms, and preferably represents an alkylene group having 1 to 5 carbon atoms.

  These diamines can be used alone or in combination of two or more.

  The tetracarboxylic dianhydride contained in the polyimide resin (A) is a tetracarboxylic dianhydride other than the tetracarboxylic dianhydride (α) having a carbonyl group other than the carbonyl group constituting the imide ring. May include. Other tetracarboxylic dianhydrides are not particularly limited, but aromatic tetracarboxylic dianhydrides are preferably used from the viewpoint of heat resistance, and aliphatic tetracarboxylic dianhydrides are used from the viewpoint of flexibility. It is preferable.

  Examples of aromatic tetracarboxylic dianhydrides include pyromellitic dianhydride, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride, 1,2,1 ′, 2′-biphenyltetra Carboxylic dianhydride, 2,3,2 ′, 3′-biphenyltetracarboxylic dianhydride, 1,2,2 ′, 3-biphenyltetracarboxylic dianhydride, bis (3,4-dicarboxyphenyl) ) Ether dianhydride, bis (3,4-dicarboxyphenyl) sulfide dianhydride, bis (3,4-dicarboxyphenyl) sulfone dianhydride, bis (3,4-dicarboxyphenyl) methane dianhydride 2,2-bis (3,4-dicarboxyphenyl) propane dianhydride, 2,2-bis (3,4-dicarboxyphenyl) -1,1,1,1,3,3,3-hexafluoropropane Dianhydride, 1,3-bis (3,4-dicarboxyphenoxy) benzene dianhydride 1,4-bis (3,4-dicarboxyphenoxy) benzene dianhydride, 4,4′-bis (3,4-dicarboxyphenoxy) biphenyl dianhydride, 2,2-bis [(3,4 -Dicarboxyphenoxy) phenyl] propane dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, 2,2 ', 3 , 3′-benzophenonetetracarboxylic dianhydride, 2,2 ′, 3,3′-biphenyltetracarboxylic dianhydride, 2,2-bis (2,3-dicarboxyphenyl) propane dianhydride, 2 , 2-bis (2,3-dicarboxyphenyl) -1,1,1,3,3,3-hexafluoropropane dianhydride, bis (2,3-dicarboxyphenyl) ether dianhydride, bis ( 2,3-Dicarboxyphenyl) sulfide dianhydride, bis (2,3-dicarboxyphenyl) Sulfone dianhydride, 1,3-bis (2,3-dicarboxyphenoxy) benzene dianhydride, 1,4-bis (2,3-dicarboxyphenoxy) benzene dianhydride, 1,2,5,6 -Naphthalenetetracarboxylic dianhydride, 4,4'-isophthaloyldiphthalic anhydride diazodiphenylmethane-3,3 ', 4,4'-tetracarboxylic dianhydride, diazodiphenylmethane-2,2', 3 , 3'-tetracarboxylic dianhydride, 2,3,6,7-thioxanthone tetracarboxylic dianhydride, 2,3,6,7-anthraquinone tetracarboxylic dianhydride, 2,3,6,7 -Xanthonetetracarboxylic dianhydride, ethylenetetracarboxylic dianhydride and the like are included.

  Examples of aliphatic tetracarboxylic dianhydrides include cyclobutane tetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic acid Dianhydride, bicyclo [2.2.1] heptane-2,3,5,6-tetracarboxylic dianhydride, bicyclo [2.2.2] oct-7-ene-2,3,5,6 -Tetracarboxylic dianhydride, bicyclo [2.2.2] octane-2,3,5,6-tetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic acid dianhydride, bicyclo [2 2.2.1] Heptane-2,3,5-tricarboxylic acid-6-acetic dianhydride, 1-methyl-3-ethylcyclohex-1-ene-3- (1,2), 5,6-tetra Carboxylic dianhydride, decahydro-1,4,5,8-dimethanonaphthalene-2,3,6,7-tetracarboxylic dianhydride, 4- (2,5-dioxoteto Hydrofuran-3-yl) - tetralin-1,2-dicarboxylic acid dianhydride, 3,3 ', and the like 4,4'-dicyclohexyl tetracarboxylic dianhydride.

  When the tetracarboxylic dianhydride includes an aromatic ring such as a benzene ring, some or all of the hydrogen atoms on the aromatic ring are fluoro group, methyl group, methoxy group, trifluoromethyl group, and trifluoromethoxy group. It may be substituted with a group selected from groups and the like. Further, when the tetracarboxylic dianhydride contains an aromatic ring such as a benzene ring, the ethynyl group, benzocyclobuten-4′-yl group, vinyl group, allyl group, cyano group, isocyanate group depending on the purpose. , A nitrilo group, an isopropenyl group, and the like may be present as a crosslinking point. These tetracarboxylic dianhydrides can be used alone or in combination of two or more.

The other tetracarboxylic dianhydride is preferably a tetracarboxylic dianhydride represented by the formula (1). M of Formula (1) is an integer of 0-5, Preferably it is an integer of 0-1. A polyimide having a tetracarboxylic dianhydride having such a structure as a constituent component has an appropriate rigidity structure and thus has high heat resistance.

The tetracarboxylic dianhydride represented by the formula (1) is more preferably a tetracarboxylic dianhydride represented by the formulas (1A) to (1C).

  The diamine contained in the polyimide resin (A) may contain a diamine other than the diamine (β) having a carbonyl group. The other diamine is not particularly limited, but is preferably an aromatic diamine from the viewpoint of heat resistance, and is preferably an aliphatic diamine from the viewpoint of flexibility. Since the structure having a carbonyl group other than the carbonyl group constituting the imide ring is likely to be highly flexible, it is preferable to use an aromatic diamine as another diamine so as not to impair the heat resistance.

A first example of another diamine is a diamine having a benzene ring. Examples of diamines having a benzene ring include
<1> Diamine having one benzene ring such as p-phenylenediamine, m-phenylenediamine, p-xylylenediamine, m-xylylenediamine;
<2> benzidine, 3,3′-diaminodiphenyl ether, 3,4′-diaminodiphenyl ether, 4,4′-diaminodiphenyl ether, 3,3′-diaminodiphenyl sulfide, 3,4′-diaminodiphenyl sulfide, 4,4 '-Diaminodiphenyl sulfide, 3,3'-diaminodiphenyl sulfone, 3,4'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl sulfone, 3,3'-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, 3, , 4'-Diaminodiphenylmethane, 2,2-di (3-aminophenyl) propane, 2,2-di (4-aminophenyl) propane, 2- (3-aminophenyl) -2- (4-aminophenyl) Propane, 2,2-di (3-aminophenyl) -1,1,1,3,3,3-hexafluoropropane, 2,2-di (4-aminophenyl) -1,1,1,3 , 3,3-Hexafluoropropane, 2- (3-aminophenyl) -2- (4-aminophenyl) -1,1,1,3,3,3-hexafluoropropane, 1,1-di (3 -Aminophenyl) -1-phenylethane, 1,1-di (4-aminophenyl) -1-phenylethane, 1- (3-aminophenyl) -1- (4-aminophenyl) -1-phenylethane, etc. A diamine having two benzene rings;
<3> 1,3-bis (3-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene, 1,4-bis (3-aminophenoxy) benzene, 1,4-bis (4- Aminophenoxy) benzene, 4,4′-diaminoparaterphenyl, 4,4′-diaminometaterphenyl, 4,4′-diaminoorthoterphenyl, 1,3-bis (3-amino-α, α-dimethyl) Benzyl) benzene, 1,3-bis (4-amino-α, α-dimethylbenzyl) benzene, 1,4-bis (3-amino-α, α-dimethylbenzyl) benzene, 1,4-bis (4- Amino-α, α-dimethylbenzyl) benzene, 1,3-bis (3-amino-α, α-ditrifluoromethylbenzyl) benzene, 1,3-bis (4-amino-α, α-ditrifluoromethylbenzyl) ) Benzene, 1,4-bis (3-amino-α, α-ditrifluoromethylbenzen ) Benzene, 1,4-bis (4-amino-α, α-ditrifluoromethylbenzyl) benzene, 2,6-bis (3-aminophenoxy) benzonitrile, 2,6-bis (3-aminophenoxy) pyridine A diamine having three benzene rings such as;

  Second examples of other diamines include ethylenediamine, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1, Examples include alkylenediamines such as 8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, 1,11-diaminoundecane, and 1,12-diaminododecane.

  Third examples of other diamines include cyclobutane diamine, cyclohexane diamine, di (aminomethyl) cyclohexane [bis (aminomethyl) cyclohexane except 1,4-bis (aminomethyl) cyclohexane], diaminobicycloheptane, diaminomethyl. Bicycloheptane (including norbornanediamines such as norbornanediamine), diaminooxybicycloheptane, diaminomethyloxybicycloheptane (including oxanorbornanediamine), isophoronediamine, diaminotricyclodecane, diaminomethyltricyclodecane, bis (aminocyclo Hexyl) methane [or methylenebis (cyclohexylamine)], alicyclic diamines such as bis (aminocyclohexyl) isopropylidene, and the like. These diamines can be used alone or in combination of two or more.

The other diamine is preferably a diamine represented by the formula (2), more preferably a diamine represented by the formula (2A). In Formula (2) and Formula (2A), n represents an integer of 0 to 10, preferably 0 to 4. A polyimide having such a diamine as a constituent component has a reasonably rigid structure and thus has high heat resistance.

  “Tetracarboxylic dianhydride having a carbonyl group (α)” (a1 mol) with respect to the total of the tetracarboxylic dianhydride component (a mol) and the diamine component (b mol) contained in the polyimide resin (A), The preferred total ratio (a1 + b1) / (a + b) of “diamine having carbonyl group (β)” (b1 mole) is 1) aromatic only, 2) aliphatic only, 3) aromatic / aliphatic It depends on which of the mixed systems.

  1) When both “a tetracarboxylic dianhydride having a carbonyl group (α)” and “a diamine having a carbonyl group (β)” are composed only of an aromatic group, the “aromatic tetracarboxylic acid having a carbonyl group” The total ratio of “anhydride (α1)” and “aromatic diamine having a carbonyl group (β1)” is preferably 1.0 to 29.0 mol%, more preferably 2.0 to 25.0 mol%. It is.

  2) When both “tetracarboxylic dianhydride having a carbonyl group (α)” and “diamine having a carbonyl group (β)” are composed only of an aliphatic group, “aliphatic tetracarboxylic acid having a carbonyl group” The total ratio of “anhydride (α2)” and “aliphatic diamine having a carbonyl group (β2)” is preferably 1.0 to 50.0 mol%, from the viewpoint of maintaining the heat resistance of the resulting polyimide film. More preferably, it is 2.0-25.0 mol%.

  3) When “tetracarboxylic dianhydride (α) having a carbonyl group” and “diamine having a carbonyl group (β)” are an aromatic / aliphatic mixed system, the total ratio of the entire mixed system is preferably Is 1.0 to 50.0 mol%, and the total ratio of “aromatic tetracarboxylic dianhydride (α1) having a carbonyl group” and “aromatic diamine having a carbonyl group (β1)” is preferably Is 1.0 to 29.0 mol%.

  That is, when the total ratio of “tetracarboxylic dianhydride (α) having a carbonyl group” and “diamine having a carbonyl group (β)” is less than a certain amount (less than 1.0 mol%), Since there are few carbonyl groups other than the carbonyl group to comprise, interaction with the functional group on the surface of an inorganic filler (B) is hard to be fully obtained. On the other hand, if the total ratio exceeds a certain amount, a carbonyl group other than the carbonyl group constituting the imide ring may gel due to excessive reaction with the terminal amino group of the polyimide, and it may be difficult to obtain a polyimide varnish. Because there is.

  In particular, even if the compound contains the same number of carbonyl groups in the molecule, the aromatic compound is rigid and has low solubility in a solvent. Therefore, it is easier to gel and less varnish than an aliphatic compound. Therefore, the preferred total ratio of “aromatic tetracarboxylic dianhydride (α1) having a carbonyl group” and “aromatic diamine having a carbonyl group (β1)” is “aliphatic tetracarboxylic acid having a carbonyl group”. This is less than the preferred total ratio of “anhydride (α2)” and “aliphatic diamine having a carbonyl group (β2)”.

  Furthermore, with respect to the total of the tetracarboxylic dianhydride component (a mol) and the diamine component (b mol) contained in the polyimide resin (A), “tetracarboxylic dianhydride represented by the formula (1)” (a2 Mol) and "diamine represented by formula (2)" (b2 mol) (a2 + b2) / (a + b) is preferably 10.0 to 90.0 mol%, preferably 25.0 to 55. More preferably, it is 0.0 mol%. When the total proportion of the tetracarboxylic dianhydride represented by the formula (1) and the diamine represented by the formula (2) is less than 10 mol%, since the rigid skeleton contained in the polyimide resin (A) is small, This is because it is difficult to obtain the property and heat conductivity, and when it exceeds 90 mol%, it is difficult to form a varnish.

  The molar ratio of the tetracarboxylic dianhydride component a mole and the diamine component b mole contained in the polyimide resin (A) is preferably in the range of a / b = 0.8 to 1.2, 0.9 More preferably, it is -1.1. This is to obtain a polymer having a certain degree of polymerization. Furthermore, it is preferable that the mole of the diamine component to be reacted is larger than the mole of the tetracarboxylic dianhydride component a in that the molecular end of the polyimide resin is an amino group. Thus, by making the molecular end of the polyimide resin an amino group, the terminal amino group of the polyimide molecule is reacted with the “carbonyl group other than the carbonyl group constituting the imide ring” of other polyimide molecules to form a crosslinked structure. This is because the heat resistance of the polyimide can be increased.

It is preferable that the weight average molecular weight of the obtained polyimide is 1.0 × 10 ^{4 to} 1.0 × 10 ⁶ . The weight average molecular weight of polyimide can be measured by gel permeation chromatography (GPC).

  The inorganic filler (B) is not particularly limited as long as it is an inorganic substance having electrical insulation and high heat dissipation. Examples of the material include boron nitride, aluminum nitride, alumina, alumina hydrate, silicon oxide, silicon nitride, silicon carbide, diamond, hydroxyapatite, and barium titanate. A more preferable material of the inorganic filler (B) is boron nitride or the like.

  Content of an inorganic filler (B) in a resin composition can be 25-60 volume%, and it is more preferable to set it as 45-60 volume%. If the content of the inorganic filler (B) is too small, it is difficult to obtain thermal conductivity. The greater the content of the inorganic filler (B), the more heat conductivity can be imparted to the adhesive resin composition. On the other hand, if the content is too large, the adhesiveness may be lowered, and the flexibility is also high. May decrease. The adhesive resin composition of the present invention has sufficient thermal conductivity despite having a low content of the inorganic filler (B), and of course can also have high adhesiveness and flexibility.

  The average particle size of the primary particles of the inorganic filler (B) is preferably 0.1 to 30 μm. This is because the particles of the inorganic filler (B) are aggregated to form secondary particles. This is because the presence of such secondary particles makes it easy to form a heat conduction path. The average particle size of the secondary particles is preferably 2 to 30 μm.

  For example, the aspect ratio of the inorganic filler (B) is preferably 9 or more, and more preferably 16 or more. The aspect ratio of the inorganic filler (B) is “major diameter of the inorganic filler (B) / thickness of the inorganic filler (B)”. When the aspect ratio of the inorganic filler (B) is increased, the inorganic filler (B) can easily form an aggregated structure. Therefore, even if the content of the inorganic filler (B) is relatively small, sufficient thermal conductivity can be obtained. Cheap.

  The adhesive resin composition of this invention may contain arbitrary components other than a polyimide resin (A) and an inorganic filler (B). Examples of the optional component may contain a surface modifier, and examples of the surface modifier include a silane coupling agent (C). The surface modifier may be used for treating the surface of the inorganic filler.

  Examples of the silane coupling agent (C) include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (2-methoxyethoxy) silane, vinyltrichlorosilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxy Silane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-2- (aminoethyl) -3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxy Silane, 3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldimethoxy Silane, 3-glycidoxypropylmethyldiethoxysilane 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropylmethyldi Ethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, N- (1,3-dimethylbutylidene) -3- (triethoxysilyl) -1- Propanamine, N, N'-bis (3- (trimethoxysilyl) propyl) ethylenediamine, polyoxyethylenepropyltrialkoxysilane, polyethoxydimethylsiloxane, p-styryltrimethoxysilane, 3-acryloxypropyltrimethoxysilane Etc. are included.

  The filler surface may be modified by a coupling reaction of the silane coupling agent (C) with the surface of the inorganic filler (B) contained in the resin composition. Thereby, compatibility with a polyimide resin (A) can be improved and the aggregation and dispersion state of a filler can be controlled.

  Thus, although the content of the inorganic filler (B) contained in the adhesive resin composition of the present invention is relatively low, the proportion of the inorganic filler (B) contributing to heat conduction is high, and the thermal conductivity is high. It is characterized by being expensive. Therefore, the resin composition is excellent in adhesiveness, heat resistance, and flexibility and has sufficient thermal conductivity.

  Although the adhesive resin composition of the present invention has a relatively low content of the inorganic filler (B), the thermal conductivity is high because the compatibility between the polyimide resin (A) and the inorganic filler (B) is high, It is because a polyimide resin (A) covers the circumference | surroundings of an inorganic filler (B) without gap, and a void can be suppressed. That is, the “resin group other than the carbonyl group constituting the imide ring” contained in the polyimide resin (A) interacts with the functional group on the surface of the inorganic filler (B), so that the polyimide resin (A) and the inorganic filler ( This is because the compatibility of B) is enhanced, and voids can be suppressed by covering the periphery of the inorganic filler (B) with the polyimide resin (A) without any gaps. If voids can be suppressed, the gap formed of gas does not lower the thermal conductivity or the density of the filler, so that the thermal conductivity can be increased.

The thermal conductivity of the adhesive resin composition of the present invention is preferably 5.0 W / m · K or more, and more preferably 6.5 W / m · K or more. The thermal conductivity of the adhesive resin composition is measured by measuring the thermal diffusivity α, the specific heat Cp, and the density ρ, and applying them to the following formula.
Thermal conductivity λ = thermal diffusivity α × specific heat Cp × density ρ

  The adhesive resin composition of the present invention preferably has not only high heat conductivity but also high heat resistance. Such heat resistance can be obtained, for example, by adding a highly rigid group such as an aromatic group or a cycloalkylene group to the polyimide resin (A) contained in the resin composition. The glass transition temperature of the adhesive resin composition of the present invention is preferably 120 ° C. or higher and 200 ° C. or lower, more preferably 130 ° C. or higher and 180 ° C. or lower. Moreover, it is preferable that the viscoelasticity in 150 degreeC of an adhesive resin composition is 100 Mpa or more. The viscoelasticity of the adhesive resin composition can be measured by a solid viscoelasticity measuring device.

2. Method for Producing Adhesive Resin Composition The adhesive resin composition of the present invention comprises, for example, a step of preparing a polyimide varnish containing a polyimide resin (A); an inorganic filler (B) is blended in the polyimide varnish, and the varnish is stirred A step of solidifying the polyimide varnish.

  The polyimide varnish contains a polyimide resin (A) and preferably a solvent. The resin solid content concentration in the polyimide varnish is preferably 5 to 50 wt%, and more preferably 10 to 30 wt%. This is for appropriately controlling the conditions of stirring described later.

  The type of the solvent is not particularly limited, and N, N-dimethylformamide, N, N-dimethylacetamide, N, N-diethylformamide, N, N-diethylacetamide, N, N-dimethylmethoxyacetamide, dimethyl sulfoxide, hexamethyl In addition to phosphoramide, N-methyl-2-pyrrolidone, dimethylsulfone, 1,3,5-trimethylbenzene, etc., these two or more mixed solvents, or these solvents and benzene, toluene, xylene, benzonitrile, What is necessary is just a mixed solvent with a dioxane, cyclohexane, etc.

  The polyimide varnish may be prepared by mixing an acid dianhydride component and a diamine component in a solvent, synthesizing amic acid by a dehydration reaction, and further imidizing. What is necessary is just to let the acid dianhydride component and diamine component which are mix | blended be each component mentioned above.

  An inorganic filler (B) is added to the obtained polyimide varnish. The inorganic filler (B) to be added may be the inorganic filler described above. Moreover, the inorganic filler (B) to be added may be treated with a silane coupling agent (C). The inorganic filler (B) may be treated by any method, but the inorganic filler (B) is added to the aqueous solution of the silane coupling agent (C) and mixed to obtain a slurry; water is removed from the slurry. To obtain solids; the solids may be ground into particles.

  By stirring the polyimide varnish to which the inorganic filler (B) is added, the inorganic filler (B) is dispersed in the polyimide varnish. Stirring may be performed with a normal stirrer or a disperser such as a roughing machine, a three-roller, or a ball mill. The shear strength of stirring is preferably 10 Pa to 1000 Pa. If the shear strength when stirring is too large, secondary particles of the inorganic filler (B) may not be formed. On the other hand, if the shear strength when stirring is too small, huge aggregates of the inorganic filler (B) are formed, and the film forming ability may be lost. Moreover, the temperature of the polyimide varnish stirred is not specifically limited, What is necessary is just to be 10-50 degreeC.

  In any case, it is preferable to control the aggregation state or dispersion state of the inorganic filler (B) in the polyimide varnish by stirring the polyimide varnish.

  The polyimide varnish itself in which the inorganic filler (B) is dispersed may be used as an adhesive. For example, the polyimide varnish may be applied to the adherend. On the other hand, the polyimide varnish may be formed into a film and used as an adhesive film. For example, the polyimide varnish can be applied to a release-treated film and solidified, and then peeled to obtain an adhesive film. The thickness of the film is usually 10 to 200 μm.

3. Use The adhesive resin composition of the present invention is preferably used for bonding a conductor layer, preferably a metal foil. For example, it can be used for adhesion between a base resin film and a metal foil in a circuit board, a heat dissipation board, and a component-embedded board that are a laminate of a base resin film and a metal foil (preferably a copper foil). Moreover, it is good also considering the base material of a circuit board as a film which consists of an adhesive resin composition of this invention.

  The thickness of the laminate is not particularly limited as long as it is appropriately set depending on the application, but the thickness of the adhesive resin composition layer is preferably 10 to 200 μm. The laminated body may be a flexible body or a rigid body, and is appropriately set by selecting a thickness and a material according to the purpose. The metal foil contained in the laminate is patterned by etching or the like to form a conductor circuit on which a semiconductor element is mounted.

  Since the adhesive resin composition of the present invention has high thermal conductivity, when an element (such as an LSI chip) is mounted on a circuit board obtained using the adhesive resin composition of the present invention, the heat generated by the element is dissipated. Easy to make. For this reason, the adhesive resin composition of the present invention is preferably used as a heat conductive adhesive material for a heat dissipation substrate for mounting various semiconductor chips, particularly semiconductor chips having a large calorific value for power device applications.

  The semiconductor device of the present invention includes a substrate having a conductor circuit and a semiconductor element mounted on the conductor circuit. The board | substrate which has a conductor circuit may be a thing in which the metal foil in the said laminated body was patterned and became a conductor circuit.

  The material of the conductor circuit is not particularly limited as long as it is a metal having excellent conductivity, and examples thereof include copper and aluminum. The semiconductor element includes various semiconductor chips, and includes power devices and the like. The power device is a power semiconductor element having an output capacity of 100 VA or more, such as a high output capacity diode, transistor, or IC.

  When the semiconductor chip is a power device, the semiconductor device preferably further includes a heat dissipation member. Examples of the heat radiating member include a heat radiating plate, a heat sink, a cooling pipe, and the like. A heat radiating member may be used independently or may be used in combination of multiple. If a heat sink is a metal plate excellent in heat conductivity, it will not be restrict | limited in particular. Examples of the heat sink include a metal plate made of aluminum and an aluminum alloy, copper, iron, a stainless steel alloy, an Invar multilayer metal, or the like. Although the thickness of a heat sink is based also on a material, it is about 0.5-3.0 mm, for example.

  FIG. 1 is a schematic diagram showing an example of the configuration of a semiconductor device 10 of the present invention. As shown in FIG. 1, the semiconductor device 10 includes a heat sink 12, an adhesive resin composition layer 14 disposed thereon, a conductor circuit 16 disposed on the adhesive resin composition layer 14, and a conductor circuit. 16 and a power device 20 mounted via solder 18. As described above, the semiconductor device 10 radiates heat generated in the power device 20 through the conductor circuit 16 and the adhesive resin composition layer 14 by the heat radiating plate 12.

  Such a semiconductor device can be obtained by any method. For example, 1) a laminated body in which a heat sink, a dry film made of an adhesive resin composition, and a conductive foil (before a circuit pattern is formed) are laminated in this order. 2) a step of thermocompression bonding the laminate; 3) a step of obtaining a predetermined conductor circuit by chemical etching or the like of the conductor foil; and 4) a step of bonding a power device to the conductor circuit via solder; Can be obtained through

  The temperature at which the dry film made of the adhesive resin composition is attached to the conductor foil or the like may be any temperature that allows adhesion, but is, for example, about 150 to 190 ° C.

  As described above, the adhesive resin composition layer 14 has high thermal conductivity although the content of the inorganic filler is relatively small. For this reason, heat | fever which generate | occur | produces in the power device 20 can be efficiently conducted to the heat sink 12, and it can be efficiently discharged | emitted out of the system, adhere | attaching with the heat sink 12 and the conductor circuit 16 favorably. Moreover, since the adhesive resin composition layer 14 has high heat resistance, the insulation reliability is not easily impaired by the heat of the power device 20.

Abbreviations of the compounds used in Examples and Comparative Examples are shown below.
(1) Tetracarboxylic dianhydride (α) having a carbonyl group other than the carbonyl group constituting the imide ring and diamine (β) having a carbonyl group (carbonyl group-containing monomer)
a) Acid dianhydride BTDA: 3,3 ′, 4,4′-benzophenone tetracarboxylic dianhydride (aromatic tetracarboxylic dianhydride: α1)
b) Diamine DABP: 3,3′-diaminobenzophenone (aromatic diamine: β1)
14EL: Polytetramethylene oxide di-p-aminobenzoate (Elastomer 1000) (manufactured by Ihara Chemical) (aliphatic diamine: β2)
Malonamide: Diamine represented by the following formula (aliphatic diamine: β2)

(2) Other diamine / tetracarboxylic dianhydride a) Acid dianhydride s-BPDA: 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride (manufactured by JFE Chemical, the above formula (2) Rigid skeleton monomer represented by
ODPA: Oxydiphthalic dianhydride (flexible skeleton monomer)
b) Diamine APB: 1,3-bis (3-aminophenoxy) benzene (manufactured by Mitsui Chemicals)
XTJ-542: polyetheramine represented by the following formula (product name: Jeffamine, manufactured by HUNTSMAN)

1. Preparation and evaluation of polyimide film [Example 1]
Preparation of polyimide varnish In a solvent prepared by adjusting NMP and mesitylene at a ratio of 7/3, two types of diamine (APB, 14EL) and two types of acid dianhydrides (s-BPDA, BTDA) are added to APB: 14EL: s-BPDA: BTDA = 0.8: 0.2: 0.95: 0.05 was added at a molar ratio. Of these, the carbonyl group-containing monomer is BTDA (α1: 10 mol%) / 14 EL (β2: 2.5 mol%). The obtained mixture was stirred for 4 hours or more in a flask into which dry nitrogen gas could be introduced to obtain a polyamic acid solution having a resin solid content weight of 20 to 25 wt%. After sufficiently stirring, the reaction system was heated to about 180 ° C. while stirring in a flask equipped with a Dean-Stark tube, and water generated by the dehydration reaction was taken out of the system to obtain a polyimide varnish.

Preparation of Filler Boron nitride filler (brand: UHP-1, Showa Denko) is blended in the polyimide varnish so that the blending amount of the filler is 38 vol% with respect to the total weight of the resin solids and the filler, and stirred. Distributed. Stirring was carried out with initial stirring using “Awatori Rentaro (model number (ARE310), Shinky Co., Ltd.)” and then stirred and kneaded using three rolls. As a result, a polyimide varnish solution containing a filler was obtained.

Production of Film A polyimide varnish solution containing a filler was applied at a rate of 10 mm / sec on a PET film that had been subjected to a release treatment. The obtained coating film was dried at 130 ° C. for 30 minutes to remove the solvent. After drying, the film part was peeled off from the PET film using tweezers or the like to prepare a polyimide film (film thickness: 60 μm) in which the boron nitride filler was dispersed.

[Example 2]
Two kinds of diamines (APB, XTJ-542) and two kinds of acid dianhydrides (s-BPDA, BTDA) are converted into APB: XTJ-542: s-BPDA: BTDA = 0.8: 0.2: A polyimide film was produced in the same manner as in Example 1 except that it was blended at a molar ratio of 0.6: 0.4. Among the monomers constituting the polyimide, the carbonyl group-containing monomer is BTDA (α1: 20 mol%).

[Example 3]
Two kinds of diamines (APB, XTJ-542) and two kinds of acid dianhydrides (s-BPDA, BTDA) are converted into APB: XTJ-542: s-BPDA: BTDA = 0.8: 0.2: A polyimide film was produced in the same manner as in Example 1 except that it was blended at a molar ratio of 0.76: 0.24. Among the monomers constituting the polyimide, the carbonyl group-containing monomer is BTDA (α1: 12 mol%).

[Example 4]
Two kinds of diamines (APB, XTJ-542) and two kinds of acid dianhydrides (s-BPDA, BTDA) are converted into APB: XTJ-542: s-BPDA: BTDA = 0.8: 0.2: A polyimide film was produced in the same manner as in Example 1 except that it was blended at a molar ratio of 0.98: 0.02. Among the monomers constituting the polyimide, the carbonyl group-containing monomer is BTDA (α1: 1 mol%).

[Example 5]
Three kinds of diamines (APB, XTJ-542, DABP) and one kind of acid dianhydride (s-BPDA) were combined with APB: XTJ-542: DABP: s-BPDA = 0.8: 0.15: A polyimide film was produced in the same manner as in Example 1 except that it was blended at a molar ratio of 0.05: 1.0. Among the monomers constituting the polyimide, the carbonyl group-containing monomer is DABP (β1: 2.5 mol%).

[Example 6]
Three kinds of diamines (APB, XTJ-542, malonamide) and one kind of acid dianhydride (s-BPDA) were converted into APB: XTJ-542: malonamide: s-BPDA = 0.8: 0.15: A polyimide film was produced in the same manner as in Example 1 except that it was blended at a molar ratio of 0.05: 1.0. Among the monomers constituting the polyimide, the carbonyl group-containing monomer is malonamide (β2: 2.5 mol%).

[Example 7]
Two kinds of diamines (APB, XTJ-542) and two kinds of acid dianhydrides (s-BPDA, BTDA) are converted into APB: XTJ-542: s-BPDA: BTDA = 0.8: 0.2: A polyimide film was prepared in the same manner as in Example 1, except that the molar ratio was 0.75: 0.20, diamine: acid dianhydride = 1.0: 0.95, and polyimide was amine-terminated. did. Among the monomers constituting the polyimide, the carbonyl group-containing monomer is BTDA (α1: 7.5 mol%).

[Example 8]
Two kinds of diamines (APB, XTJ-542) and two kinds of acid dianhydrides (s-BPDA, BTDA) are converted into APB: XTJ-542: s-BPDA: BTDA = 0.8: 0.2: A polyimide film was prepared in the same manner as in Example 1 except that it was blended at a molar ratio of 1.0: 0.05, and diamine: acid dianhydride = 1: 1.05, and the polyimide was acid-terminated. Among the monomers constituting the polyimide, the carbonyl group-containing monomer is BTDA (α1: 2.5 mol%).

[Comparative Example 1]
Two kinds of diamines (APB, XTJ-542) and one kind of acid dianhydride (s-BPDA) are mixed with APB: XTJ-542: s-BPDA = 0.8: 0.2: 1.0. A polyimide film was produced in the same manner as in Example 1 except that it was blended in a molar ratio. The monomer constituting the polyimide does not include a carbonyl group-containing monomer.

[Comparative Example 2]
Two kinds of diamines (APB, XTJ-542) and two kinds of acid dianhydrides (BPDA, BTDA) are converted into APB: XTJ-542: BPDA: BTDA = 0.8: 0.2: 0.4: A polyimide film was produced in the same manner as in Example 1 except that it was blended at a molar ratio of 0.6. Among the monomers constituting the polyimide, the carbonyl group-containing monomer is BTDA (α1: 30 mol%).

[Comparative Example 3]
Two kinds of diamines (APB, XTJ-542) and two kinds of acid dianhydrides (ODPA, BTDA) are converted into APB: XTJ-542: ODPA: BTDA = 0.8: 0.2: 0.95: A polyimide film was produced in the same manner as in Example 1 except that it was blended at a molar ratio of 0.05. Among the monomers constituting the polyimide, the carbonyl group-containing monomer is BTDA (α1: 2.5 mol%).

[Comparative Example 4]
A polyimide film was produced in the same manner as in Example 1 except that the blending amount of the filler was 20 vol%.

  About the polyimide film obtained in Examples 1-8 and Comparative Examples 1-4, thermal conductivity and heat resistance were evaluated as follows. Moreover, about the polyimide film obtained by Example 1 and the comparative example 1, the presence or absence of the void was observed.

(1) Evaluation of thermal conductivity The thermal conductivity of the prepared polyimide film was evaluated. Specifically, the thermal conductivity was calculated by measuring “thermal diffusivity α”, “specific heat Cp” and “density ρ” of the sample, and applying the measured values to the following equation.
Thermal conductivity λ = thermal diffusivity α × specific heat Cp × density ρ

  The thermal diffusivity was measured by a laser flash method. The measuring apparatus was a laser flash method thermal constant measuring apparatus (TC-9000) manufactured by ULVAC-RIKO. Specific heat was measured by DSC method. The measuring apparatus was a Diamond DSC apparatus manufactured by PerkinElmer. The weight was measured with an electronic balance, the volume was calculated from the sample area and the sample thickness, and the density was calculated.

(2) Evaluation of heat resistance Copper foil (BHY-22B-T: Nikko Metal Co., Ltd.) was bonded to both sides of the prepared polyimide film under the conditions of 180 ° C. × 1 hour × 2.5 MPa, and polyimide / copper foil A laminate was obtained. After the obtained laminate is heat-treated in a dryer at 180 ° C. for 1 to 4 hours, the laminate is taken out every hour and the cross section of the laminate is observed with an optical microscope at a magnification of 250 times or more. Then, it was observed whether or not peeling occurred at the interface between the copper foil and the polyimide. For example, when it is not peeled after heating for 1 hour but peeled after heating for 2 hours, it is shown as “180 ° C. × 1 hr pass, 2 hr or more NG”.

(3) Evaluation of Void A sample piece of 50 μm thickness of the prepared polyimide film was prepared. Using a transmission electron microscope (TEM, H-7650: manufactured by Hitachi, Ltd.), a cross section obtained by cutting out this sample piece with a FIB processing apparatus (SMI2050: manufactured by Seiko Instruments Inc.), a magnification of 10,000 times or more. Observed. Thereby, the dispersion state of the filler in the sample piece was observed.

The evaluation results of Examples 1 to 8 and Comparative Examples 1 to 4 are shown in Table 1. In Table 1, those that could be varnished without gelation were marked with ◯, and those that gelled and could not be varnished were marked with ×.

  The polyimide films of Examples 1 to 8 have better thermal conductivity (5.0 W / m · K or more) than the polyimide films obtained in Comparative Examples 1 to 4 despite the same filler content. It can be seen that it has heat resistance.

  In addition, in the polyimide film of Example 1, the periphery of the inorganic filler is covered with a polyimide resin without a gap and there is no void (see FIG. 2A), whereas in the polyimide film of Comparative Example 1, the inorganic filler It was confirmed that there was a portion (void) that was not covered with polyimide resin (see FIG. 2B). Thus, it is thought that the high thermal conductivity was obtained in the polyimide films of Examples 1 to 8 because voids were significantly suppressed as compared with Comparative Examples 1 to 4.

  Furthermore, in Example 7, the heat resistance was remarkably improved by making the molecular end of the polyimide an amino group. This is presumably because the amino group at the molecular end of the polyimide reacted with a carbonyl group (other than the carbonyl group constituting the imide ring) of the polyimide to form a crosslinked structure.

  On the other hand, in Comparative Example 2, gelation occurred during the preparation of the polyimide varnish, and the polyimide varnish could not be obtained. Since the carbonyl group-containing monomer (other than the carbonyl group constituting the imide ring) is an aromatic monomer and has a rigid skeleton, it has a low solubility in a solvent and is likely to precipitate; This is thought to be due to the fact that they are easily attracted and precipitated.

  Although the polyimide obtained in Comparative Example 3 contains a carbonyl group that does not constitute an imide ring, it can be seen that the heat resistance is low. This is considered because polyimide contains many flexible skeletons derived from ODPA. From this, in order to obtain heat resistance above a certain level, it is considered that polyimide needs to include a rigid skeleton such as a skeleton derived from BPDA to some extent.

2. Polyimide varnish formation test [Example 9]
Preparation of polyimide varnish One type of diamine (APB) and two types of acid dianhydrides (s-BPDA, BTDA) in a solvent prepared by adjusting NMP and mesitylene at a ratio of 7/3, APB: s- It was blended at a molar ratio of BPDA: BTDA = 1.0: 0.75: 0.25. Of these, the carbonyl group-containing monomer is BTDA (α1: 12.5 mol%). The obtained mixture was stirred for 4 hours or more in a flask capable of introducing dry nitrogen gas to obtain a polyamic acid solution having a resin solid content weight of 25 wt%. After sufficiently stirring, the reaction system was heated to about 180 ° C. while stirring in a flask equipped with a Dean-Stark tube, and water generated by the dehydration reaction was taken out of the system to obtain a polyimide varnish.

[Example 10]
Two kinds of diamines (APB, XTJ-542) and two kinds of acid dianhydrides (s-BPDA, BTDA) are combined into APB: XTJ-542: s-BPDA: BTDA = 0.8: 0.2: A polyamic acid solution was prepared in the same manner as in Example 9 except that a molar ratio of 0.6: 0.4 was added to obtain a polyimide varnish. Of these, the carbonyl group-containing monomer is BTDA (α1: 20.0 mol%).

[Example 11]
Two kinds of diamines (APB, XTJ-542) and two kinds of acid dianhydrides (s-BPDA, BTDA) are combined into APB: XTJ-542: s-BPDA: BTDA = 0.8: 0.2: A polyamic acid solution was prepared in the same manner as in Example 9 except that it was blended at a molar ratio of 0.25: 0.6 to obtain a polyimide varnish. Of these, the carbonyl group-containing monomer is BTDA (α1: 30.0 mol%).

[Example 12]
Two kinds of diamines (APB, XTJ-542) and two kinds of acid dianhydrides (s-BPDA, BTDA) are combined into APB: XTJ-542: s-BPDA: BTDA = 0.8: 0.2: A polyamic acid solution was prepared in the same manner as in Example 9 except that the polyamic acid solution was blended at a molar ratio of 0.4: 0.6 and the resin solid content weight of the polyamic acid solution was 5 wt% to obtain a polyimide varnish. It was. Of these, the carbonyl group-containing monomer is BTDA (α1: 30.0 mol%).

[Example 13]
Example 9 except that one kind of diamine (14EL) and one kind of acid dianhydride (s-BPDA) were blended in a molar ratio of 14EL: s-BPDA = 1.0: 1.0. A polyamic acid solution was prepared in the same manner as above to obtain a polyimide varnish. Among these, the carbonyl group-containing monomer is 14EL (β2: 50.0 mol%).

[Comparative Example 5]
Two kinds of diamines (APB, XTJ-542) and two kinds of acid dianhydrides (s-BPDA, BTDA) are combined into APB: XTJ-542: s-BPDA: BTDA = 0.8: 0.2: A polyamic acid solution was prepared in the same manner as in Example 9 except that it was blended at a molar ratio of 0.4: 0.6, and an attempt was made to obtain a polyimide varnish. Of these, the carbonyl group-containing monomer is BTDA (α1: 30.0 mol%). However, the varnish gelled and a polyimide varnish could not be obtained.

[Comparative Example 6]
One kind of diamine (14EL) and two kinds of acid dianhydrides (s-BPDA, BTDA) are blended at a molar ratio of 14EL: s-BPDA: BTDA = 1.0: 0.4: 0.6 Except for this, a polyamic acid solution was prepared in the same manner as in Example 9 to obtain a polyimide varnish. Of these, the carbonyl group-containing monomer is BTDA (α1) 30.0 mol% / 14 EL (β2) 50.0 mol%; the rigid skeleton monomer is s-BPDA 20.0 mol%. However, the varnish gelled and a polyimide varnish could not be obtained.

Table 2 shows the results of whether or not varnishing is possible in Examples 9 to 13 and Comparative Examples 5 to 6. In Table 2, those that could be varnished without gelation were marked with ◯, and those that gelled and could not be varnished were marked with ×. Moreover, about what could be varnished, what was able to produce the polyimide film was made into (circle); what was not able to be produced was set as x.

  As shown in Table 2, whether or not a polyimide can be varnished depends on the monomer (carbonyl group-containing monomer) skeleton (aromatic or aliphatic) containing a carbonyl group other than the carbonyl group constituting the imide ring; It turns out that it depends on the skeleton monomer content; the resin solid content concentration of the polyamic acid and the like.

  From Examples 9 to 10 and Comparative Example 5, when the carbonyl group-containing monomer is aromatic, it can be varnished if the content is less than 30 mol% with respect to the total monomer, but when it is 30 mol% or more It turns out that it gelatinizes and cannot be varnished. On the other hand, Example 13 shows that when the carbonyl group-containing monomer is aliphatic, it can be varnished even with a content of 50 mol% with respect to the total monomers.

  From Example 11 and Comparative Example 5, it can be seen that even when the content of the aromatic carbonyl group-containing monomer is 30 mol%, the varnish can be formed if the acid / diamine ratio is small. Moreover, it can be seen from Example 12 and Comparative Example 5 that even when the content of the aromatic carbonyl group-containing monomer is 30 mol%, the polyamic acid can be varnished by reducing the resin solid content concentration.

  A laminate can be obtained by using the adhesive resin composition of the present invention as an adhesive between a conductor layer and a film. The laminate can be applied to, for example, a circuit board, a heat dissipation board, a component built-in board, and the like. The laminate can be a circuit board having particularly high thermal conductivity and further high heat resistance. In addition, when the element (such as an LSI chip) is mounted on the circuit board, heat from the element can be efficiently dissipated.

DESCRIPTION OF SYMBOLS 10 Semiconductor device 12 Heat sink 14 Adhesive resin composition layer 16 Conductor circuit 18 Solder 20 Power device

Claims (11)

A thermally conductive adhesive resin composition comprising a polyimide resin (A) and 25 to 60% by volume of an inorganic filler (B),
The polyimide resin (A) includes a polycondensation unit of tetracarboxylic dianhydride and diamine,
The tetracarboxylic dianhydride may contain an aromatic tetracarboxylic dianhydride (α1) having a carbonyl group other than the carbonyl group constituting the imide ring,
The diamine includes an aromatic diamine having a carbonyl group (β1) (excluding 2,5-bis (4-aminobenzoyl) thiophene),
Wherein among the tetracarboxylic acid dianhydride of the total of the diamine, the total proportion of 1.0 mol% 29.0 mol of the aromatic tetracarboxylic dianhydride ([alpha] 1) and the aromatic diamine (.beta.1) %, And a carbonyl group other than a carbonyl group constituting the imide ring of the aromatic tetracarboxylic dianhydride (α1) constitutes a keto group, an oxycarbonyl group or a dioxycarbonyl group,
The carbonyl group of the aromatic diamine (β1) is a keto group, an oxycarbonyl group, a dioxycarbonyl group, or an amide group (however, the nitrogen atom contained in the amide group is a nitrogen atom constituting an imide ring) )
Before Kite tetracarboxylic dianhydride comprises a tetracarboxylic dianhydride represented by the formula (1), thermally-conductive adhesive resin composition.
[M in Formula (1) is an integer of 0 or more] A thermally conductive adhesive resin composition comprising a polyimide resin (A) and 25 to 60% by volume of an inorganic filler (B),
The polyimide resin (A) includes a polycondensation unit of tetracarboxylic dianhydride and diamine,
The tetracarboxylic dianhydride may include an aliphatic tetracarboxylic dianhydride (α2) having a carbonyl group other than the carbonyl group constituting the imide ring,
The diamine includes an aliphatic diamine having a carbonyl group (β2),
Of the total of the diamine and the tetracarboxylic dianhydride, the total proportion of the aliphatic tetracarboxylic dianhydride ([alpha] 2) and the aliphatic diamine (.beta.2) is 1.0 mol% or more 50.0 And a carbonyl group other than the carbonyl group constituting the imide ring of the aliphatic tetracarboxylic dianhydride (α2) comprises a keto group, an oxycarbonyl group or a dioxycarbonyl group,
The carbonyl group of the aliphatic diamine (β2) is a keto group, an oxycarbonyl group, a dioxycarbonyl group, or an amide group (wherein the nitrogen atom contained in the amide group is a nitrogen atom constituting an imide ring) )
Before Kite tetracarboxylic dianhydride comprises a tetracarboxylic dianhydride represented by the formula (1), thermally-conductive adhesive resin composition.
[M in Formula (1) is an integer of 0 or more] A thermally conductive adhesive resin composition comprising a polyimide resin (A) and 25 to 60% by volume of an inorganic filler (B),
The polyimide resin (A) includes a polycondensation unit of tetracarboxylic dianhydride and diamine,
The tetracarboxylic dianhydride may contain a tetracarboxylic dianhydride (α) having a carbonyl group other than the carbonyl group constituting the imide ring,
The diamine includes a diamine (β) having a carbonyl group (excluding 2,5-bis (4-aminobenzoyl) thiophene),
Wherein of the total of the tetracarboxylic dianhydride and the diamine, the total proportion of the tetracarboxylic dianhydride (alpha) and the diamine (beta) is 1.0 mol% or more 50.0 mol% Yes (Of these, the total ratio of the aromatic tetracarboxylic dianhydride (α1) having a carbonyl group other than the carbonyl group constituting the imide ring and the aromatic diamine (β1) having a carbonyl group is 1.0 mol% A carbonyl group other than the carbonyl group constituting the imide ring of the tetracarboxylic dianhydride (α) is a keto group, an oxycarbonyl group or a dioxycarbonyl group. Configure
The carbonyl group of the diamine (β) is a keto group, an oxycarbonyl group, a dioxycarbonyl group, or an amide group (however, the nitrogen atom contained in the amide group is a nitrogen atom constituting an imide ring). Configure
Before Kite tetracarboxylic dianhydride comprises a tetracarboxylic dianhydride represented by the formula (1), thermally-conductive adhesive resin composition.
[M in Formula (1) is an integer of 0 or more] The said inorganic filler (B) is boron nitride, and the heat conductivity of the said heat conductive adhesive resin composition is 5.0 W / m * K or more, It is any one of Claims 1-3. Thermally conductive adhesive resin composition. The tetracarboxylic dianhydride represented by said Formula (1) is a tetracarboxylic dianhydride represented by Formula (1A)-(1C), It is any one of Claims 1-4. Thermally conductive adhesive resin composition.
  The heat conductive adhesive resin composition as described in any one of Claims 1-5 whose molecular terminal of the said polyimide resin (A) is an amino group.   The heat conductive adhesive resin composition according to any one of claims 1 to 6, wherein the inorganic filler (B) has an aspect ratio of 9 or more. A resin layer comprising the thermally conductive adhesive resin composition according to any one of claims 1 to 7,
And a conductor layer disposed on one side or both sides of the resin layer. A resin layer comprising the thermally conductive adhesive resin composition according to any one of claims 1 to 7,
A conductor layer disposed on one or both sides of the resin layer and having a predetermined circuit pattern;
A semiconductor device comprising: a semiconductor element joined to the conductor layer.   The semiconductor device according to claim 9, wherein the semiconductor element is a power semiconductor element having an output capacity of 100 VA or more.   The semiconductor device according to claim 9, wherein the resin layer is disposed on a heat sink.