JP6333576B2 - Thermosetting resin composition, semiconductor device and electric / electronic component - Google Patents

Description

  The present invention relates to a thermosetting resin composition, a semiconductor device manufactured using the thermosetting resin composition, and an electric / electronic component.

  The problem of heat generated during the operation of semiconductor products has become more prominent with the increase in capacity, high-speed processing, and fine wiring of semiconductor products. So-called thermal management, which releases heat from semiconductor products, is an increasingly important issue. It has become to. For this reason, a method of attaching a heat radiating member such as a heat spreader or a heat sink to a semiconductor product is generally employed, and a material having a higher thermal conductivity of the material itself to which the heat radiating member is bonded has been desired.

  On the other hand, depending on the form of the semiconductor product, in order to make thermal management more efficient, there is a method of bonding a heat spreader to the die pad portion of the lead frame to which the semiconductor element itself or the semiconductor element is bonded, or the die pad portion on the package surface. A method (for example, refer to Patent Document 1) of providing a function as a heat sink by exposing is adopted.

  Further, the semiconductor element may be bonded to an organic substrate having a heat dissipation mechanism such as a thermal via. Also in this case, high thermal conductivity is required for the material for bonding the semiconductor element. In addition, due to the recent increase in brightness of white light emitting LEDs, it has been widely used in backlight devices for full-color liquid crystal screens, lighting devices such as ceiling lights and downlights. By the way, there is a problem that the adhesive for bonding the light emitting element and the substrate is discolored by heat, light or the like, or the electrical resistance value changes with time due to high current input due to high output of the light emitting element. . In particular, in the method of completely relying on the adhesive strength of the adhesive for bonding, there is a fear of a fatal problem that the bonding material loses the adhesive strength at the solder melting temperature and peels off when the electronic component is soldered, leading to non-lighting. Further, the enhancement of the performance of the white light emitting LED leads to an increase in the amount of heat generated from the light emitting element chip, and accordingly, the LED structure and the members used therefor are also required to improve the heat dissipation.

  In particular, in recent years, the development of power semiconductor devices using wide band gap semiconductors such as silicon carbide (SiC) and gallium nitride with low power loss has become active, the element itself has high heat resistance, and has a high current of 250 ° C. or higher. High temperature operation is possible. However, in order to exhibit the characteristics, it is necessary to efficiently dissipate the heat generated by the operation, and there is a demand for a bonding material that has excellent long-term high-temperature heat resistance in addition to conductivity and heat conductivity.

  As described above, high thermal conductivity is required for materials (such as die attach paste and heat radiating member bonding material) used for bonding each member of the semiconductor device and the electric / electronic component. In addition, these materials must be able to withstand reflow processing when the product is mounted on the substrate at the same time, and in many cases, adhesion of a large area is required. It is also necessary to have a low stress property to suppress this.

  Here, usually, in order to obtain an adhesive having high thermal conductivity, a metal filler such as silver powder or copper powder or a ceramic filler such as aluminum nitride or boron nitride is used as a filler with a high content in the organic binder. It is necessary to disperse (see, for example, Patent Document 2). However, as a result, the elastic modulus of the cured product becomes high, and it has been difficult to have both good thermal conductivity and good reflow properties (that is, peeling does not easily occur after the reflow treatment).

  However, recently, as a candidate for a bonding method that can withstand such a demand, a bonding method using silver nanoparticles that enables bonding under conditions lower than that of bulk silver has come to be noted (for example, (See Patent Document 3).

JP 2006-86273 A JP 2005-113059 A JP 2011-240406 A

  However, since joining with silver nanoparticles usually requires pressurization and heating at the time of joining, there are problems such as possible damage to the element and lack of versatility due to problems with the apparatus.

  In addition, the atmosphere when forming a bonded body using silver nanoparticles is such that the organic substance covering the surface of the silver nanoparticles is removed by oxidative decomposition, so that an oxidizing atmosphere such as the atmosphere is essential. Therefore, when a base material such as copper is used, there is a possibility of causing poor adhesion of the sealing material due to its own oxidation, and this effect is considered to be remarkable particularly in a fine joined body. . Therefore, if it is possible to provide a bonding material that exhibits sufficient bonding force under an inert atmosphere such as nitrogen, it is possible to prevent oxidation of the base material, and dramatically expand the application field and possibilities of the bonding agent. It becomes possible.

  Therefore, the present invention is excellent in reliability by using a resin composition having excellent thermal conductivity, excellent low stress properties, good adhesive properties and reflow peeling resistance, and the resin composition as an adhesive material. An object is to provide a semiconductor device and an electric / electronic component.

  The thermosetting resin composition of the present invention comprises (A) plate-type silver fine particles, (B) silver powder having an average particle diameter other than the component (A) of 0.5 to 30 μm, and (C) thermosetting. Resin, and the total amount of the silver fine particles of the component (A) and the silver powder of the component (B) is 100 parts by mass, the component (C) is blended in an amount of 1 to 20 parts by mass. And

  In the thermosetting resin composition, the (A) plate-type silver fine particles preferably have a center particle diameter of 0.3 to 15 μm and a thickness of 10 to 200 nm, and are self-baked at 150 to 250 ° C. It is preferable to tie. Moreover, it is preferable that the (C) thermosetting resin is a cyanate resin, an epoxy resin, an acrylic resin, or a maleimide resin. Furthermore, it is preferable that mass ratio of (A) component and (B) component is 10: 90-90: 10.

  The semiconductor device of the present invention is characterized in that the resin composition of the present invention is used as a die attach material, and a semiconductor element is bonded onto a substrate.

  The electrical / electronic component of the present invention is characterized in that the resin composition of the present invention is used as a heat radiating member bonding material, and the heat radiating member is bonded to the heat generating member.

  Since the thermosetting resin composition of the present invention is excellent in thermal conductivity, excellent in low stress properties, excellent in adhesive properties and excellent in reflow peeling resistance, the thermosetting resin composition is used as a die attach paste for device adhesion or It is suitable as a heat radiating member bonding material. Moreover, it becomes possible to provide a semiconductor device and electrical / electronic parts having excellent reliability by using these adhesive materials.

  As described above, the thermosetting resin composition of the present invention includes (A) plate-type silver fine particles, (B) silver powder, and (C) a thermosetting resin. .

  By adopting such a configuration, when the (A) plate-type silver fine particles are sintered, the thermal conductivity is higher than that of a normal silver powder alone, and mainly sintered in the minor axis direction. Compared to those using silver nano-particles, the internal stress is small, and the silver particles are highly oriented so that the bonding material is excellent in reflectivity. This (A) plate-type silver fine particle is unlikely to be affected by the presence or absence of oxygen, unlike ordinary silver fine particles (silver nanoparticles), and thus can be sintered in an inert gas atmosphere such as nitrogen. Furthermore, the resin composition of the present invention can be bonded without applying pressure, and is excellent in adhesiveness. Therefore, the semiconductor device and the electric / electronic component produced using the thermosetting resin composition as a die attach paste or a heat dissipation member bonding material have excellent reflow resistance.

Hereinafter, the present invention will be described in detail.
(A) Plate-type silver fine particles used in the present invention, unlike spherical nanoparticles, are plate-like flaky particles having a uniform thickness obtained by greatly growing one metal crystal surface, and having a resin composition Well-known plate-type silver fine particles that can be blended into the product can be mentioned. In general, the size is on the order of microns and the thickness is about several nanometers, and it has shapes such as a triangular plate shape, a hexagonal plate shape, and a truncated triangular plate shape. Moreover, it is preferable that the upper surface is widely covered with the [111] plane.

  The (A) plate-type silver fine particles preferably have a center particle diameter of 0.3 to 15 μm. By setting it within this range, dispersibility in the resin component can be improved, and the problem of nozzle clogging and chip distortion during assembly of the semiconductor element can be suppressed. Here, the central particle size refers to a 50% integrated value (50% particle size) in a volume-based particle size distribution curve obtained by measurement with a laser diffraction particle size distribution measuring device.

  Moreover, it is preferable that the long side of the direction perpendicular | vertical to a thickness direction exists in the range of 8 to 150 times of thickness, and it is more preferable that it is 10 to 50 times. Further, the short side in the direction perpendicular to the thickness direction is preferably in the range of 1 to 100 times the thickness, and more preferably 3 to 50 times.

  The (A) plate-type silver fine particles can be self-sintered at 100 to 250 ° C. By containing silver fine particles that self-sinter at 100 to 250 ° C. in this way, the flowability of the silver fine particles is improved during thermosetting, and as a result, the number of contacts between the silver fine particles is increased and the area of the contacts is increased. Becomes larger and the conductivity is remarkably improved. Therefore, the sintering temperature of the plate-type silver particles is more preferably 100 to 200 ° C. Here, self-sinterable means that sintering is performed by heating at a temperature lower than the melting point without applying pressure or additives.

  Further, (A) the plate-type silver fine particles are preferably single crystals. By using a single crystal, it is possible to ensure conductivity at low temperature curing.

  (A) The plate-type silver fine particles are oriented in the horizontal direction in the coating film, have more contacts, and can improve conductivity. This is a natural orientation so that the thickness direction is laminated in the coating film due to the compression effect due to the weight of the chip during thermosetting and the volume exclusion effect that the volume shrinks due to the reduction of the volatile component of resin composition and curing shrinkage, etc. This is because a large contact between the silver fine particles can be secured.

  Moreover, it is also preferable from a viewpoint of compatibility improvement to surface-treat the surface of (A) plate-type silver fine particles as needed. The type of surface treatment is not particularly limited and can be appropriately selected depending on the component (B) or component (C). For example, in order to improve the compatibility, stearic acid, palmitic acid, hexanoic acid, oleic acid and the like can be mentioned.

  Examples of such (A) plate-type silver fine particles include M612 (trade name; center particle diameter 6 to 12 μm, particle thickness 60 to 100 nm, melting point 250 ° C.), M27 (trade name; center) manufactured by Toxen Industries, Ltd. Particle diameter 2-7 μm, particle thickness 60-100 nm, melting point 200 ° C.), M13 (trade name; center particle diameter 1-3 μm, particle thickness 40-60 nm, melting point 200 ° C.), N300 (trade name; center particle diameter 0. 3 to 0.6 μm, a particle thickness of 50 nm or less, and a melting point of 150 ° C.). These plate-type silver fine particles may be used alone or in combination. In particular, in order to improve the filling rate, for example, among the above-described plate-type silver fine particles, it is also preferable to use a combination of relatively large silver fine particles such as M27 and M13 and small particles such as N300.

  Furthermore, in addition to (A) plate-type silver fine particles, spherical silver fine particles having an average particle diameter of 10 to 100 nm may be added. Thereby, the filling rate is further improved and low-temperature sinterability can be imparted as compared with the combination of only the plate-type silver fine particles and the silver powder described later.

  The silver powder (B) used in the present invention is a silver powder having an average particle size of 0.2 to 30 μm, and may be a silver powder as an inorganic filler that is usually added to impart conductivity to the resin adhesive. That's fine. The bonding strength between the element and the support substrate can be further improved by adding micron-order silver particles such as (B) silver powder in addition to the silver fine particles of the component (A). Moreover, as a shape of the silver particle used here, flake shape, scale shape, dendritic shape, rod shape, wire shape, spherical shape etc. are mentioned, for example. The component (B) does not include silver fine particles corresponding to the component (A).

  Here, the average particle size refers to a 50% integrated value (50% particle size) in a volume-based particle size distribution curve obtained by measurement with a laser diffraction particle size distribution analyzer.

  In addition, when the ratio of these (A) component and (B) component makes these total amount 100, mass ratio of (A) component: (B) component may be 10: 90-90: 10. Preferably, 10: 90-50: 50 is more preferable. When the component (A) is too small relative to the component (B), it is difficult to ensure high thermal conductivity, and when the component (A) is too large, voids are generated in the cured product, and thixotropy increases during mounting. There is a risk that workability may be deteriorated due to the threading phenomenon of the thread.

  The (C) thermosetting resin used in the present invention can be used without any particular limitation as long as it is a thermosetting resin generally used as an adhesive. Among these, a liquid resin is preferable, and a resin that is liquid at room temperature (25 ° C.) is more preferable. Examples of the (C) thermosetting resin include cyanate resin, epoxy resin, radical polymerizable acrylic resin, maleimide resin, and the like.

  The cyanate resin is a compound having an —NCO group in the molecule, and forms a three-dimensional network structure by the reaction of the —NCO group by heating to be cured. Specifically, 1,3-dicyanatobenzene, 1,4-dicyanatobenzene, 1,3,5-tricyanatobenzene, 1,3-dicyanatonaphthalene, 1,4-dicyanatonaphthalene, 1, 6-dicyanatonaphthalene, 1,8-dicyanatonaphthalene, 2,6-dicyanatonaphthalene, 2,7-dicyanatonaphthalene, 1,3,6-tricyanatonaphthalene, 4,4'-dicyanatobiphenyl, bis (4-cyanatophenyl) methane, bis (3,5-dimethyl-4-cyanatophenyl) methane, 2,2-bis (4-cyanatophenyl) propane, 2,2-bis (3,5-dibromo -4-Cyanatophenyl) propane, bis (4-cyanatophenyl) ether, bis (4-cyanatophenyl) thioether, bis (4-cyanatophenyl) Sulfone, tris (4-cyanatophenyl) phosphite, tris (4-cyanatophenyl) phosphate, and the like cyanates obtained by a reaction between novolak resin and a cyanogen halide. Moreover, the prepolymer which has a triazine ring formed by trimerizing the cyanate group of these polyfunctional cyanate resin can also be used. This prepolymer is obtained by polymerizing the above polyfunctional cyanate resin monomer using, for example, an acid such as a mineral acid or Lewis acid, a base such as sodium alcoholate or tertiary amine, or a salt such as sodium carbonate as a catalyst. can get.

  As the curing accelerator for the cyanate resin, generally known ones can be used. Examples include organometallic complexes such as zinc octylate, tin octylate, cobalt naphthenate, zinc naphthenate and acetylacetone iron, metal salts such as aluminum chloride, tin chloride and zinc chloride, and amines such as triethylamine and dimethylbenzylamine. However, it is not limited to these. These curing accelerators can be used alone or in combination. In addition, the cyanate resin can be used in combination with other resins such as an epoxy resin, an oxetane resin, an acrylic resin, and a maleimide resin.

  The epoxy resin is a compound having one or more glycidyl groups in the molecule, and is a resin that forms a three-dimensional network structure by the reaction of the glycidyl groups by heating and cures. It is preferable that two or more glycidyl groups are contained in one molecule, but this is because sufficient cured product characteristics cannot be exhibited even if the glycidyl group is reacted with only one compound. A compound containing two or more glycidyl groups in one molecule can be obtained by epoxidizing a compound having two or more hydroxyl groups. Examples of such compounds include bisphenol compounds such as bisphenol A, bisphenol F, and biphenol, or derivatives thereof, hydrogenated bisphenol A, hydrogenated bisphenol F, hydrogenated biphenol, cyclohexanediol, cyclohexanedimethanol, and shidilohexanediethanol. Diol having an alicyclic structure or a derivative thereof, a bifunctional one obtained by epoxidizing an aliphatic diol such as butanediol, hexanediol, octanediol, nonanediol, decanediol or the like, a trihydroxyphenylmethane skeleton, Trifunctional compounds obtained by epoxidizing compounds having an aminophenol skeleton, phenol novolak resins, cresol novolak resins, phenol aralkyl resins, biphenyls Aralkyl resins, and the naphthol aralkyl resin as polyfunctional epoxidized include, without limitation thereto. Moreover, since this epoxy resin is pasty or liquid at room temperature as a resin composition, it is preferable that it is liquid at room temperature alone or as a mixture. It is also possible to use reactive diluents as is usual. Examples of the reactive diluent include monofunctional aromatic glycidyl ethers such as phenyl glycidyl ether and cresyl glycidyl ether, and aliphatic glycidyl ethers.

  At this time, a curing agent is used for the purpose of curing the epoxy resin. Examples of the curing agent for the epoxy resin include aliphatic amines, aromatic amines, dicyandiamide, dihydrazide compounds, acid anhydrides, and phenol resins. . Examples of the dihydrazide compound include carboxylic acid dihydrazides such as adipic acid dihydrazide, dodecanoic acid dihydrazide, isophthalic acid dihydrazide, and p-oxybenzoic acid dihydrazide. Acid anhydrides include phthalic anhydride, tetrahydrophthalic anhydride, hexahydroanhydride. Examples thereof include phthalic acid, endomethylenetetrahydrophthalic anhydride, dodecenyl succinic anhydride, a reaction product of maleic anhydride and polybutadiene, and a copolymer of maleic anhydride and styrene.

  A phenol resin used as a curing agent for an epoxy resin is a compound having two or more phenolic hydroxyl groups in one molecule. In the case of a compound having one phenolic hydroxyl group in one molecule, a cross-linked structure may be taken. Therefore, the cured product characteristics deteriorate and cannot be used.

  The number of phenolic hydroxyl groups in one molecule can be used as long as it is 2 or more, but the number of phenolic hydroxyl groups is preferably 2 to 5. When the amount is larger than this, the molecular weight becomes too large, and the viscosity of the conductive paste becomes too high, which is not preferable. The number of phenolic hydroxyl groups in one molecule is more preferably 2 or 3.

  Such compounds include bisphenol F, bisphenol A, bisphenol S, tetramethyl bisphenol A, tetramethyl bisphenol F, tetramethyl bisphenol S, dihydroxy diphenyl ether, dihydroxy benzophenone, tetramethyl biphenol, ethylidene bisphenol, methyl ethylidene bis (methyl phenol). ), Bisphenols such as cyclohexylidene bisphenol and biphenol and derivatives thereof, trifunctional phenols such as tri (hydroxyphenyl) methane and tri (hydroxyphenyl) ethane, and phenols such as phenol novolac and cresol novolac A compound obtained by reacting formaldehyde with formaldehyde, which is mainly dinuclear or trinuclear and its derivatives Body and the like.

Furthermore, a curing accelerator can be blended in order to accelerate curing. Examples of epoxy resin curing accelerators include imidazoles, triphenylphosphine or tetraphenylphosphine and salts thereof, amine compounds such as diazabicycloundecene, and the like. Examples thereof include salts thereof. For example, 2-methylimidazole, 2-ethylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2-phenyl-4,5-dihydroxymethyl Imidazole compounds such as imidazole, 2-C ₁₁ H ₂₃ -imidazole, and an adduct of 2-methylimidazole and 2,4-diamino-6-vinyltriazine are preferably used. Particularly preferred is an imidazole compound having a melting point of 180 ° C. or higher. The epoxy resin is also preferably used in combination with a cyanate resin, an acrylic resin, or a maleimide resin.

  The radical polymerizable acrylic resin is a compound having a (meth) acryloyl group in the molecule, and is a resin that forms a three-dimensional network structure by the reaction of the (meth) acryloyl group and cures. It is preferable that one or more (meth) acryloyl groups are contained in the molecule.

  Here, examples of the acrylic resin include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, and 3-hydroxybutyl. (Meth) acrylate, 4-hydroxybutyl (meth) acrylate, 1,2-cyclohexanediol mono (meth) acrylate, 1,3-cyclohexanediol mono (meth) acrylate, 1,4-cyclohexanediol mono (meth) acrylate, 1,2-cyclohexanedimethanol mono (meth) acrylate, 1,3-cyclohexanedimethanol mono (meth) acrylate, 1,4-cyclohexanedimethanol mono (meth) acrylate, 1,2-cyclohexanedi Tanol mono (meth) acrylate, 1,3-cyclohexanediethanol mono (meth) acrylate, 1,4-cyclohexanediethanol mono (meth) acrylate, glycerin mono (meth) acrylate, glycerin di (meth) acrylate, trimethylolpropane mono ( Has hydroxyl groups such as (meth) acrylate, trimethylolpropane di (meth) acrylate, pentaerythritol mono (meth) acrylate, pentaerythritol di (meth) acrylate, pentaerythritol tri (meth) acrylate, neopentyl glycol mono (meth) acrylate (Meth) acrylates and (meth) acrylates having a carboxy group obtained by reacting (meth) acrylates having these hydroxyl groups with dicarboxylic acids or derivatives thereof Such as theft and the like. Examples of the dicarboxylic acid usable here include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, maleic acid, fumaric acid, phthalic acid, and tetrahydrophthalic acid. Hexahydrophthalic acid and derivatives thereof.

  Furthermore, methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, isodecyl (meth) acrylate, lauryl (meth) acrylate, tridecyl (Meth) acrylate, cetyl (meth) acrylate, stearyl (meth) acrylate, isoamyl (meth) acrylate, isostearyl (meth) acrylate, behenyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, other alkyl (meth) Acrylate, cyclohexyl (meth) acrylate, t-butylcyclohexyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, benzyl (meth) acrylate, phenoxyethyl (meth) ) Acrylate, isobornyl (meth) acrylate, glycidyl (meth) acrylate, trimethylolpropane tri (meth) acrylate, zinc mono (meth) acrylate, zinc di (meth) acrylate, dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate , Neopentyl glycol (meth) acrylate, trifluoroethyl (meth) acrylate, 2,2,3,3-tetrafluoropropyl (meth) acrylate, 2,2,3,3,4,4-hexafluorobutyl (meth) ) Acrylate, perfluorooctyl (meth) acrylate, perfluorooctylethyl (meth) acrylate, ethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, 1,4-buta Diol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, 1,3-butanediol di (meth) acrylate, 1,10-decanediol di ( (Meth) acrylate, tetramethylene glycol di (meth) acrylate, methoxyethyl (meth) acrylate, butoxyethyl (meth) acrylate, ethoxydiethylene glycol (meth) acrylate, methoxypolyalkylene glycol mono (meth) acrylate, octoxypolyalkylene glycol mono (Meth) acrylate, Lauroxy polyalkylene glycol mono (meth) acrylate, Stearoxy polyalkylene glycol mono (meth) acrylate, Allyloxy polyalkylene glycol (Meth) acrylate, nonylphenoxypolyalkylene glycol mono (meth) acrylate, acryloylmorpholine, hydroxyethylacrylamide, N, N′-methylenebis (meth) acrylamide, N, N′-ethylenebis (meth) acrylamide, 1, 2-di (meth) acrylamide ethylene glycol, di (meth) acryloyloxymethyltricyclodecane, N- (meth) acryloyloxyethylmaleimide, N- (meth) acryloyloxyethylhexahydrophthalimide, N- (meta It is also possible to use acryloyloxyethyl phthalimide, n-vinyl-2-pyrrolidone, styrene derivatives, α-methylstyrene derivatives and the like.

  Particularly preferable acrylic resins include polyethers having a molecular weight of 100 to 10,000, polyesters, polycarbonates, poly (meth) acrylates having (meth) acrylic groups, hydroxyl group-containing (meth) acrylates, and hydroxyl groups. And (meth) acrylamide.

  Here, the polyether skeleton is preferably one in which an organic group having 1 to 6 carbon atoms is repeated via an ether bond, and preferably does not contain an aromatic ring. A compound having a (meth) acryl group in a polyether can be obtained by a reaction between a polyether polyol and (meth) acrylic acid or a derivative thereof.

  As the polyester skeleton, those in which an organic group having 1 to 6 carbon atoms is repeated via an ester bond are preferable, and those having no aromatic ring are preferable. A compound having a (meth) acrylic group in polyester can be obtained by a reaction between a polyester polyol and (meth) acrylic acid or a derivative thereof.

  The polycarbonate skeleton is preferably one in which an organic group having 1 to 6 carbon atoms is repeated via a carbonate bond, and preferably does not contain an aromatic ring. A compound having a (meth) acrylic group in polycarbonate can be obtained by a reaction between a polycarbonate polyol and (meth) acrylic acid or a derivative thereof.

As a poly (meth) acrylate skeleton, a copolymer of (meth) acrylic acid and (meth) acrylate, a (meth) acrylate having a hydroxyl group and a (meth) acrylate having no polar group such as a carboxyl group and a hydroxyl group; And a copolymer of (meth) acrylate having a glycidyl group and (meth) acrylate having no polar group is preferable.
The above-mentioned copolymer can be obtained by reacting with a (meth) acrylate having a hydroxyl group having a hydroxyl group or a (meth) acrylate having a glycidyl group, and (meth) acrylic acid having a hydroxyl group having no polar group and It is possible to obtain it by reacting with its derivative, and it can be obtained by reacting with (meth) acrylic acid and its derivative whose glycidyl group does not have a polar group.
And the compound which has a (meth) acryl group with poly (meth) acrylate can be obtained by reaction with a poly (meth) acrylate polyol, and (meth) acrylic acid or its derivative (s).

The (meth) acrylate or (meth) acrylamide having a hydroxyl group is a (meth) acrylate or (meth) acrylamide having at least one (meth) acryl group in one molecule, and contains a hydroxyl group. To do.
The (meth) acrylate having a hydroxyl group can be obtained by reacting a polyol compound with a (meth) acrylic acid derivative. This reaction can use a well-known reaction, and usually uses 0.5-5 times mole acrylic acid ester or acrylic acid with respect to a polyol compound.
Further, (meth) acrylamide having a hydroxyl group can be obtained by reacting an amine compound having a hydroxyl group with (meth) acrylic acid and a derivative thereof. The method of producing (meth) acrylamides by reacting (meth) acrylic acid esters with amine compounds is based on the fact that the double bonds of (meth) acrylic acid esters are extremely reactive, so amines, cyclopentadiene, alcohols In general, the compound is previously added to the double bond as a protecting group, and after completion of the amidation, the product is heated to remove the protecting group to produce the target product.
Thus, by containing a hydroxyl group, the sinterability by a reduction effect is accelerated | stimulated and adhesiveness improves.

  Moreover, the hydroxyl group here is an alcoholic group in which a hydrogen atom of an aliphatic hydrocarbon group is substituted, and the content of this hydroxyl group is preferably 1 to 50 per molecule, If the amount is within this range, it is preferable because there is no inhibition of sinterability due to excessive curing.

  Examples of the acrylic resin compound having a hydroxyl group include compounds represented by the following general formulas (I) to (IV).

（式中、Ｒ^１は水素原子又はメチル基を表し、Ｒ^２は炭素数１〜１００の２価の脂肪族炭化水素基又は環状構造を持つ脂肪族炭化水素基を表す。）

(In the formula, R ¹ represents a hydrogen atom or a methyl group, and R ² represents a divalent aliphatic hydrocarbon group having 1 to 100 carbon atoms or an aliphatic hydrocarbon group having a cyclic structure.)

（式中、Ｒ^１及びＲ^２はそれぞれ上記と同じものを表す。）

(In the formula, R ¹ and R ² are the same as described above.)

（式中、Ｒ^１は上記と同じものを表し、ｎは１〜５０の整数を表す。）

(Wherein, ^{R 1} represents the same as above, n is an integer of 1 to 50.)

（式中、Ｒ^１及びｎはそれぞれ上記と同じものを表す。）

(Wherein R ¹ and n each represent the same as above)

As this (meth) acrylate or (meth) acrylamide, the above-mentioned compounds can be used alone or in combination of two or more. In general formulas (I) and (II), the carbon number of R ² is preferably 1 to 100, more preferably 1 to 36, and the carbon number of R ² is in such a range. This is preferable because there is no inhibition of sinterability due to excessive curing.

  Here, when the component (C) is an acrylic resin, a polymerization initiator is generally used for the polymerization. However, as the polymerization initiator, a thermal radical polymerization initiator is preferable, and a known thermal radical polymerization initiator is used. If there is no particular limitation, it can be used. In addition, as the thermal radical polymerization initiator, those having a decomposition temperature of 40 to 140 ° C. in a rapid heating test (decomposition start temperature when 1 g of a sample is placed on an electric heating plate and heated at 4 ° C./min). preferable. When the decomposition temperature is less than 40 ° C., the preservability of the conductive paste at room temperature deteriorates, and when it exceeds 140 ° C., the curing time becomes extremely long. Specific examples of the thermal radical polymerization initiator satisfying such characteristics include methyl ethyl ketone peroxide, methylcyclohexanone peroxide, methyl acetoacetate peroxide, acetylacetone peroxide, 1,1-bis (t-butylperoxy) 3, 3,5-trimethylcyclohexane, 1,1-bis (t-hexylperoxy) cyclohexane, 1,1-bis (t-hexylperoxy) 3,3,5-trimethylcyclohexane, 1,1-bis (t- Butylperoxy) cyclohexane, 2,2-bis (4,4-di-t-butylperoxycyclohexyl) propane, 1,1-bis (t-butylperoxy) cyclododecane, n-butyl-4, 4-bis (t-butylperoxy) valerate, 2,2-bis (t-butyl) -Oxy) butane, 1,1-bis (t-butylperoxy) -2-methylcyclohexane, t-butyl hydroperoxide, p-menthane hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide , T-hexyl hydroperoxide, dicumyl peroxide, 2,5-dimethyl-2,5-bis (t-butylperoxy) hexane, α, α'-bis (t-butylperoxy) diisopropylbenzene, t -Butyl cumyl peroxide, di-t-butyl peroxide, 2,5-dimethyl-2,5-bis (t-butylperoxy) hexyne-3, isobutyryl peroxide, 3,5,5-trimethylhexa Noyl peroxide, octanoyl peroxide, lauroyl peroxide, cinnamic acid Oxide, m-toluoyl peroxide, benzoyl peroxide, diisopropyl peroxydicarbonate, bis (4-t-butylcyclohexyl) peroxydicarbonate, di-3-methoxybutyl peroxydicarbonate, di-2-ethylhexyl Peroxydicarbonate, di-sec-butylperoxydicarbonate, di (3-methyl-3-methoxybutyl) peroxydicarbonate, di (4-t-butylcyclohexyl) peroxydicarbonate, α, α ′ -Bis (neodecanoylperoxy) diisopropylbenzene, cumylperoxyneodecanoate, 1,1,3,3-tetramethylbutylperoxyneodecanoate, 1-cyclohexyl-1-methylethylperoxyneo Decanoate, t-heki Luperoxyneodecanoate, t-butylperoxyneodecanoate, t-hexylperoxybivalate, t-butylperoxybivalate, 2,5-dimethyl-2,5-bis (2-ethylhexanoyl) Peroxy) hexane, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate, 1-cyclohexyl-1-methylethylperoxy-2-ethylhexanoate, t-hexylperoxy 2-ethylhexanoate, t-butylperoxy-2-ethylhexanoate, t-butylperoxyisobutyrate, t-butylperoxymaleic acid, t-butylperoxylaurate, t-butyl Peroxy-3,5,5-trimethylhexanoate, t-butylperoxyisopropyl monocarbo Tate, t-butylperoxy-2-ethylhexyl monocarbonate, 2,5-dimethyl-2,5-bis (benzoylperoxy) hexane, t-butylperoxyacetate, t-hexylperoxybenzoate, t -Butylperoxy-m-toluoylbenzoate, t-butylperoxybenzoate, bis (t-butylperoxy) isobutarate, t-butylperoxyallyl monocarbonate, 3,3 ', 4,4'-tetra (t -Butylperoxycarbonyl) benzophenone and the like can be mentioned, but these can be used alone or in combination of two or more in order to control curability. The radical polymerizable acrylic resin is also preferably used in combination with a cyanate resin, an epoxy resin, or a maleimide resin.

  These polymerization initiators may be used alone or in combination of two or more in order to control curability. Furthermore, various polymerization inhibitors can be added in advance in order to improve the storage stability of the die attach paste.

  As for the compounding quantity of this thermal radical initiator, 0.1-10 mass parts is preferable with respect to 100 mass parts of radically polymerizable acrylic resin components. If the amount exceeds 10 parts by mass, the change in the viscosity of the die attach paste may increase with time, which may cause problems in workability. If the amount is less than 0.1 parts by mass, the curability may be significantly reduced.

  The maleimide resin is a compound that contains one or more maleimide groups in one molecule, and forms a three-dimensional network structure when the maleimide group reacts by heating, and is cured. For example, N, N ′-(4,4′-diphenylmethane) bismaleimide, bis (3-ethyl-5-methyl-4-maleimidophenyl) methane, 2,2-bis [4- (4-maleimidophenoxy) phenyl ] A bismaleimide resin such as propane may be mentioned. More preferred maleimide resins are compounds obtained by reaction of dimer acid diamine and maleic anhydride, and compounds obtained by reaction of maleimidated amino acids such as maleimide acetic acid and maleimide caproic acid with polyols. The maleimidated amino acid is obtained by reacting maleic anhydride with aminoacetic acid or aminocaproic acid. As the polyol, polyether polyol, polyester polyol, polycarbonate polyol, poly (meth) acrylate polyol is preferable, and an aromatic ring is formed. What does not contain is especially preferable.

  Since the maleimide group can react with an allyl group, the combined use with an allyl ester resin is also preferable. The allyl ester resin is preferably an aliphatic one, and particularly preferred is a compound obtained by transesterification of a cyclohexane diallyl ester and an aliphatic polyol. The number average molecular weight of the allyl ester compound is not particularly limited, but is preferably 500 to 10,000, and particularly preferably 500 to 8,000. When the number average molecular weight is within the above range, curing shrinkage can be particularly reduced, and deterioration of adhesion can be prevented. Moreover, combined use with cyanate resin, an epoxy resin, and an acrylic resin is also preferable.

The maleimide resin is a bismaleimide resin having an aliphatic hydrocarbon group in the main chain, and the main chain connecting two maleimide groups has an aliphatic hydrocarbon group having 1 or more carbon atoms. Those are particularly preferred.
Here, the aliphatic hydrocarbon group may be any of linear, branched and cyclic forms, preferably having 6 or more carbon atoms, more preferably 12 or more carbon atoms, It is particularly preferable that the number of carbon atoms is 24 or more. The aliphatic hydrocarbon group is preferably directly bonded to the maleimide group.

（式中、Ｑは炭素数６以上の２価の直鎖状、分枝鎖状又は環状の脂肪族炭化水素基を示し、Ｐは２価の原子又は有機基であって、Ｏ、ＣＯ、ＣＯＯ、ＣＨ_２、Ｃ（ＣＨ_３）_２、Ｃ（ＣＦ_３）_２、Ｓ、Ｓ_２、ＳＯ及びＳＯ_２から選ばれる２価の原子又は有機基を少なくとも１つ以上含む基であり、ｍは１〜１０の整数を表す。）も好ましく用いられる。 Moreover, as a maleimide resin, for example, a compound represented by the following general formula (V)

(In the formula, Q represents a divalent linear, branched or cyclic aliphatic hydrocarbon group having 6 or more carbon atoms, P is a divalent atom or organic group, and O, CO, M is a group containing at least one divalent atom or organic group selected from COO, CH ₂ , C (CH ₃ ) ₂ , C (CF ₃ ) ₂ , S, S ₂ , SO and SO _2; Represents an integer of 1 to 10.) is also preferably used.

Here, examples of the divalent atom represented by P include O and S, and examples of the divalent organic group include CO, COO, CH ₂ , C (CH ₃ ) ₂ , C (CF ₃ ) ₂ , S ₂ , SO, SO _{2 and the} like, and organic groups containing at least one or more of these atoms or organic groups are exemplified. Examples of the organic group including the above-described atom or organic group include those having a hydrocarbon group having 1 to 3 carbon atoms, a benzene ring, a cyclo ring, a urethane bond, etc. as a structure other than the above, and as P in that case Examples include groups represented by the following chemical formula.

Use of a bismaleimide resin having an aliphatic hydrocarbon group in the main chain is preferable because it provides a thermosetting resin composition for semiconductor adhesion that is excellent in heat resistance and good in heat bond strength after moisture absorption at low stress. .
Specific examples of such maleimide resins include BMI-1500 (manufactured by Designer Molecules, trade name; molecular weight 1500), BMI-1700 (manufactured by Diginer Molecules, trade name: molecular weight 1700), and the like. Is mentioned.

  Further, the maleimide resin is particularly preferably used in combination with an allylated epoxy resin which is a polymer of allylated bisphenol and epichlorohydrin or a radical polymerizable acrylic resin containing the hydroxy group.

  Here, an allylated epoxy resin that is a polymer of allylated bisphenol and epichlorohydrin is, for example, a polyhydric phenol compound dissolved in a solvent such as alcohols such as methanol, isopropanol and n-propanol, or ketones such as acetone and methyl ethyl ketone. Then, after reaction with an allyl halide such as allyl chloride or allyl bromide using a base such as sodium hydroxide or potassium hydroxide to obtain an allyl ether of a polyhydric phenol compound, an allylated polyphenol compound and an epihalohydrin Can be obtained by reacting at 20 to 120 ° C. for 0.5 to 10 hours while adding or gradually adding solids of alkali metal hydroxides such as sodium hydroxide and potassium hydroxide as a catalyst to the mixture. .

（式中、Ｒ^３〜Ｒ^１０は、それぞれ独立に水素原子、置換又は無置換のアルキル基及び置換又は無置換のアリル基から選ばれる基であって、そのうちの少なくとも１つは置換又は無置換のアリル基であり、ＸはＳＯ、ＳＯ_２、ＣＨ_２、Ｃ（ＣＨ_３）_２、Ｃ（ＣＦ_３）_２、Ｏ、ＣＯ及びＣＯＯから選ばれる２価の原子又は有機基であり、ｋは０又は１である。）が好ましく用いられる。 An allylated epoxy resin is a compound represented by the following general formula (VI)

Wherein R ^{3 to} R ¹⁰ are each independently a group selected from a hydrogen atom, a substituted or unsubstituted alkyl group and a substituted or unsubstituted allyl group, at least one of which is substituted or unsubstituted X is a divalent atom or organic group selected from SO, SO ₂ , CH ₂ , C (CH ₃ ) ₂ , C (CF ₃ ) ₂ , O, CO and COO, and k is 0 or 1) is preferably used.

  When the maleimide resin and the allylated epoxy resin are used in combination, the blending ratio is preferably 50/50 to 95/5, and more preferably 65/35 to 90/10.

  When the maleimide resin and the radical polymerizable acrylic resin are used in combination, the blending ratio is preferably 5/95 to 95/5.

  Here, (C) component is mix | blended so that it may become 1-20 mass parts, when the total amount of the silver fine particle of said (A) component and the silver powder of (B) component is 100 mass parts. When the component (C) is less than 1 part by mass, the silver component is excessively increased, so that the viscosity is too high and handling is difficult, which is not preferable as an adhesive. When the component (C) exceeds 20 parts by mass, the ratio of the silver component is reduced, so that high thermal conductivity is insufficient and heat dissipation is reduced. In addition, since the organic component is large, the lifetime of the light emitting device is deteriorated, which is deteriorated by light and heat, and as a result, coloring and strength are reduced. By setting it as such a blending range, it is possible to easily prevent the silver particles from contacting each other and to maintain the mechanical strength of the entire adhesive layer by utilizing the adhesive performance of the acrylic resin.

  The present invention essentially contains the components (A) to (C) as essential components, but may contain components (D) to (F) described below as necessary. .

  In the present invention, (D) an organic substance as a flux component may be added. Here, a flux component means what has the flux activity which removes the oxide film of a base material. Examples of the (D) flux component include carboxylic acids.

  The carboxylic acids may be either aliphatic carboxylic acids or aromatic carboxylic acids. Examples of the aliphatic carboxylic acid include malonic acid, methylmalonic acid, dimethylmalonic acid, ethylmalonic acid, allylmalonic acid, 2,2′-thiodiacetic acid, 3,3′-thiodipropionic acid, 2,2′- (Ethylenedithio) diacetic acid, 3,3′-dithiodipropionic acid, 2-ethyl-2-hydroxybutyric acid, dithiodiglycolic acid, diglycolic acid, acetylenedicarboxylic acid, maleic acid, malic acid, 2-isopropylmalic acid , Tartaric acid, itaconic acid, 1,3-acetone dicarboxylic acid, tricarbaric acid, muconic acid, β-hydromuconic acid, succinic acid, methyl succinic acid, dimethyl succinic acid, glutaric acid, α-ketoglutaric acid, 2-methylglutaric acid, 3-methylglutaric acid, 2,2-dimethylglutaric acid, 3,3-dimethylglutaric acid, 2,2-bis (hydroxymethyl) ) Propionic acid, citric acid, adipic acid, 3-tert-butyladipic acid, pimelic acid, phenyloxalic acid, phenylacetic acid, nitrophenylacetic acid, phenoxyacetic acid, nitrophenoxyacetic acid, phenylthioacetic acid, hydroxyphenylacetic acid, dihydroxyphenylacetic acid, Mandelic acid, hydroxymandelic acid, dihydroxymandelic acid, 1,2,3,4-butanetetracarboxylic acid, suberic acid, 4,4′-dithiodibutyric acid, cinnamic acid, nitrocinnamic acid, hydroxycinnamic acid, dihydroxycinnamic acid, Coumaric acid, phenylpyruvic acid, hydroxyphenylpyruvic acid, caffeic acid, homophthalic acid, tolylacetic acid, phenoxypropionic acid, hydroxyphenylpropionic acid, benzyloxyacetic acid, phenyllactic acid, tropic acid, 3- (phenylsulfonyl) propiate Acid, 3,3-tetramethylene glutaric acid, 5-oxoazeleic acid, azelaic acid, phenylsuccinic acid, 1,2-phenylenediacetic acid, 1,3-phenylenediacetic acid, 1,4-phenylenediacetic acid, benzyl Malonic acid, sebacic acid, dodecanedioic acid, undecanedioic acid, diphenylacetic acid, benzylic acid, dicyclohexylacetic acid, tetradecanedioic acid, 2,2-diphenylpropionic acid, 3,3-diphenylpropionic acid, 4,4-bis (4 -Hydroxyphenyl) valeric acid, pimaric acid, parastrinic acid, isopimaric acid, abietic acid, dehydroabietic acid, neoabietic acid, agatic acid and the like. Examples of the aromatic carboxylic acid include benzoic acid, 2-hydroxybenzoic acid, 3-hydroxybenzoic acid, 4-hydroxybenzoic acid, 2,3-dihydroxybenzoic acid, 2,4-dihydroxybenzoic acid, 2,5- Dihydroxybenzoic acid, 2,6-dihydroxybenzoic acid, 3,4-dihydroxybenzoic acid, 2,3,4-trihydroxybenzoic acid, 2,4,6-trihydroxybenzoic acid, 3,4,5-trihydroxy Benzoic acid, 1,2,3-benzenetricarboxylic acid, 1,2,4-benzenetricarboxylic acid, 1,3,5-benzenetricarboxylic acid, 2- [bis (4-hydroxyphenyl) methyl] benzoic acid, 1- Naphthoic acid, 2-naphthoic acid, 1-hydroxy-2-naphthoic acid, 2-hydroxy-1-naphthoic acid, 3-hydroxy-2-naphthoic acid, 6- Droxy-2-naphthoic acid, 1,4-dihydroxy-2-naphthoic acid, 3,5-dihydroxy-2-naphthoic acid, 3,7-dihydroxy-2-naphthoic acid, 2,3-naphthalenedicarboxylic acid, 2, Examples include 6-naphthalenedicarboxylic acid, 2-phenoxybenzoic acid, biphenyl-4-carboxylic acid, biphenyl-2-carboxylic acid, and 2-benzoylbenzoic acid. Among these, from the viewpoint of storage stability and availability, succinic acid, malic acid, itaconic acid, 2,2-bis (hydroxymethyl) propionic acid, adipic acid, 3,3′-thiodipropionic acid, 3 , 3′-dithiodipropionic acid, 1,2,3,4-butanetetracarboxylic acid, suberic acid, sebacic acid, phenylsuccinic acid, dodecanedioic acid, diphenylacetic acid, benzylic acid, 4,4-bis (4- Hydroxyphenyl) valeric acid, abietic acid, 2,5-dihydroxybenzoic acid, 3,4,5-trihydroxybenzoic acid, 1,2,4-benzenetricarboxylic acid, 1,3,5-benzenetricarboxylic acid, 2- [Bis (4-hydroxyphenyl) methyl] benzoic acid or the like is preferably used. These compounds may be used alone or in combination of two or more.

  (D) As for a flux component, dicarboxylic acid is especially preferable, and the thing whose decomposition temperature is 100-300 degreeC, Preferably 150-290 degreeC is preferable. Not only the removal of the oxide film on the bonding substrate, but also the surface treatment agent of component (A) and component (B) by exchange reaction during bonding heating, the removal of the oxide film and silver oxide contained in it, and the dicarboxylic acid Since it decomposes or evaporates, it does not interfere with the subsequent sintering of silver. By this, the sintering promotion effect that silver sinters at a lower temperature than before addition is obtained. If the boiling point of this (D) flux component is less than 100 ° C., the volatility will be high even at room temperature, so that the reduction ability is likely to decrease due to volatilization of the dispersion medium, and stable adhesive strength can be obtained. There is a risk of disappearing. Further, when the boiling point of the flux component (D) exceeds 300 ° C., it is difficult to sinter the conductive film, and it is not preferable because the flux component remains in the film without being dense and not volatile.

  (D) As content of a flux component, it is preferable that it is 0.01-5 mass parts with respect to a total of 100 mass parts of (A) component and (B) component. If the content exceeds 5 parts by mass, the reliability due to the generation of voids may be adversely affected. If the content is less than 0.01 parts by mass, the flux activity may not function, which is not preferable.

  Further, in the present invention, (E) a solvent may be used. (E) If a solvent functions as a reducing agent, a well-known solvent can be used. As this solvent, alcohol is preferable, and examples thereof include aliphatic polyhydric alcohols. Examples of the aliphatic polyhydric alcohol include glycols such as ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 1,4-butanediol, glycerin, and polyethylene glycol. These solvents can be used alone or in combination of two or more.

  (E) As a solvent, an alcohol solvent that functions as a reducing agent is heated to a high temperature by heat treatment during paste curing (sintering), thereby increasing the reducing power of the alcohol and partially present in silver powder and silver fine particles. Silver oxide and metal oxide on the metal substrate (for example, copper oxide) are reduced by alcohol to become pure metal, and as a result, a hardened film having higher density and higher conductivity and high adhesion to the substrate can be formed. It is thought that. In addition, the alcohol is partly refluxed during the heat treatment when curing the paste by being sandwiched between the semiconductor element and the metal substrate, and the alcohol as the solvent is not immediately lost from the system due to volatilization, and the paste has a boiling point or higher. The metal oxide is reduced more efficiently at the curing temperature.

  (E) Specifically, the solvent has a boiling point of 100 to 300 ° C, preferably 150 to 290 ° C. If the boiling point is less than 100 ° C., the volatility is high even at room temperature, so that the reduction ability is easily reduced due to volatilization of the dispersion medium, and stable adhesive strength cannot be obtained. On the other hand, if the boiling point exceeds 300 ° C., it is difficult to sinter the conductive film, it lacks denseness, and does not volatilize, leaving the solvent in the film, which is not preferable.

  (E) It is preferable that the compounding quantity of a solvent is 7-20 mass parts, when the total amount of (A) component and (B) component is 100 mass parts. If the amount is less than 7 parts by mass, the viscosity may be increased and workability may be reduced. If the amount exceeds 20 parts by mass, the viscosity may be reduced, and silver settling and reliability in the paste may be reduced.

(F) The resin particles are not particularly limited as long as they are resin particles.
The average particle size of the resin particles (F) used in the present invention is preferably 0.5 to 50 μm, more preferably 0.8 to 20 μm, more preferably 0.8 to 10 μm, and particularly preferably 0.8. 8-5 μm.

  (F) When the average particle diameter of the resin particles is within this range, silver in a high temperature environment can be obtained by “physical obstacle effect” that restricts the sintering path between silver particles without impairing workability and bonding strength. It becomes possible to suppress the progress of sintering of the fine particles. Thereby, since generation | occurrence | production of a firing void is suppressed and it is excellent in reflow peeling tolerance and heat cycle tolerance, it is preferable. Furthermore, it is preferable because the thermal shock resistance is improved by the stress relaxation ability.

  In addition, it becomes easy to disperse | distribute uniformly in the sintered joining layer by making the average particle diameter of (F) resin particle small particle diameter, for example, 20 micrometers or less, and suppression of sintering progress is more effective. It can be carried out. Here, the average particle size of (F) resin particles refers to the number average particle size calculated from the particle size distribution measured by a laser diffraction particle size distribution measuring device.

  (F) The material of the resin particles is not particularly limited as long as it is made of resin as described above, but, for example, silicone powder and a crosslinked polymer can be preferably used. Further, if the progress of the sintering can be suppressed, the shape of the (F) resin particles is not particularly limited, and a spherical shape, an indefinite shape, or the like is used. In order to effectively suppress the progress of sintering, it is preferable to disperse and blend in (F) thermosetting resin, as in (A) silver fine particles, (B) silver powder, and the like. Therefore, it is preferable that the spherical shape has good dispersibility.

Examples of the silicone powder include silicone rubber particles having a structure in which linear dimethylpolysiloxane is crosslinked, and a silicone resin that is a cured product of polyorganosilsesquioxane having a structure in which siloxane bonds are crosslinked in a three-dimensional network. Examples include particles and silicone composite particles in which the surface of silicone rubber particles is coated with a silicone resin. From the viewpoint of heat resistance and dispersibility, silicone resin or silicone composite particles are more preferable.
Specific examples of commercially available silicone powders include, for example, silicone composite powders (KMP-600, KMP-601, KMP-602, KMP-605, X-52-7030, etc.) manufactured by Shin-Etsu Chemical Co., Ltd. Silicone rubber powder (KMP-597, KMP-598, KMP-594, X-52-875, etc.), silicone resin powder (KMP-590, KMP-701, X-52-854, X-52-1621, etc.) These may be used alone or in combination of two or more.

  Examples of the crosslinked polymer include divinylbenzene, methyl methacrylate resin (PMMA), ethyl methacrylate resin (PEMA), butyl methacrylate resin (PBMA), methyl methacrylate-ethyl methacrylate copolymer, and mixtures thereof. Among them, a divinylbenzene crosslinked polymer and a methyl methacrylate resin, which are excellent in heat resistance and stability, are preferable.

  Furthermore, (F) resin particles may be metal-coated with gold or silver on the surface. When the resin particles are coated with metal, in addition to the “physical obstacle effect” that restricts the sintering path between the silver particles, the sintering progress of the silver particles reaches the metal coating on the surface of the resin particles (F) The “termination effect” that stops at is preferable because it is possible to suppress the progress of sintering of silver fine particles in a high-temperature environment, the generation of firing voids is suppressed, and reflow peeling resistance and heat cycle resistance are excellent. Examples of such metal-coated resin particles include trade name “Micropearl AU series” manufactured by Sekisui Fine Chemical Co., Ltd.

In addition, in the (F) resin particles of the present invention, in addition to suppressing the generation of voids, the compression elastic modulus (30% K value) is 500 to 4000 N / mm ² , and the compression recovery rate is 5% from the viewpoint of improving the adhesion. It is preferable to use resin particles having a characteristic of ˜40%. The characteristics of the resin particles are more preferably a compression elastic modulus (30% K value) of 500 to 3000 N / mm ² and a compression recovery rate of 5% to 30%.
When the compression elastic modulus and the compression recovery rate are in the above ranges, the generation of voids can be suppressed during the heat curing and sintering of the resin composition, and the adhesion between the resin and silver particles, chips, etc. is improved. Thus, a resin composition capable of suppressing the occurrence of distortion and deformation of the chip at the time of mounting or holding at a high temperature can be obtained.

If the compression elastic modulus (30% K value) of the resin particles is less than 500 N / mm ² , the degree of cross-linking is insufficient, the heat resistance is low, and the resin particles are easily deformed due to the volume shrinkage during sintering. Therefore, if the effect of suppressing deformation of the chip becomes weak and the compressive elastic modulus exceeds 4000 N / mm ² , it cannot follow the sintering shrinkage at the time of curing the composition, so that there is a risk of lowering adhesion and generating voids.

  If the compression recovery rate of the resin particles is less than 5%, the sintering shrinkage at the time of curing the composition cannot be followed, and there is a risk that the sintered voids remain or the adhesiveness decreases. On the other hand, if the compression deformation rate exceeds 40%, the chip may be deformed without being able to follow the volume shrinkage during sintering, thereby causing the chip to be deformed.

ここで、Ｆは３０％圧縮変形における荷重値（Ｎ）、Ｓは３０％圧縮変形における圧縮変位（ｍｍ）、Ｒは樹脂粒子の半径（ｍｍ）を示す。 The compression modulus (30% K value) is defined by the following mathematical formula (1).

Here, F represents a load value (N) in 30% compression deformation, S represents a compression displacement (mm) in 30% compression deformation, and R represents a radius (mm) of the resin particles.

The compression modulus (30% K value) is measured as follows.
Using a micro compression tester (for example, Shimadzu Dynamic Ultra Micro Hardness Tester DUH-W201 (manufactured by Shimadzu Corporation)), spherical resin particles are compressed at a smooth end surface of a cylinder made of diamond having a diameter of 50 μm at a compression speed of 2.6 mN / sec. , And a maximum test load of 10 g, and a load value (N) at 30% compression deformation and a displacement (mm) at 30% compression deformation are measured and calculated by the above formula (1).

The compression recovery rate is defined by the following mathematical formula (2).

Compression recovery rate (%) = [(L1-L2) / L1] × 100 (2)

The compression recovery rate is the shape recovery rate from the compression deformation state in an atmosphere of 20 ° C., and the calculation is based on the method described in Japanese Examined Patent Publication No. 7-95165. Shimadzu Dynamic Ultra Hardness Tester DUH-W201 (manufactured by Shimadzu Corporation)), spherical resin particles were compressed at a compression speed of 2.6 mN / sec and a maximum test load of 10 g on a smooth end surface of a 50 μm diameter cylinder made of diamond. It is the value which expressed in% the ratio of the total deformation amount (L1) and the plastic deformation amount (L2) obtained by compressing under conditions and obtaining from the hysteresis curve of the load and the deformation amount.

  Such resin particles are preferably the above-mentioned crosslinked polymer. Further, spherical particles are preferable because compression recovery can function uniformly in all directions. Furthermore, when a crosslinked polymer is used, the size of the resin particles can be controlled according to the synthesis conditions, and spherical particles having a desired size can be easily produced. In this case, it is preferable because the resin particles need not be post-processed after synthesis.

  Further, in addition to the suppression of the above-described sintering progress, when mounting the semiconductor chip on the support substrate, in order to suppress the deformation and distortion of the chip, the (F) resin particles have an average particle diameter of 10 to 50 μm. It is preferred to use particles. At this time, as the resin particles used for suppressing deformation and distortion of the chip, (B) resin particles having an average particle size larger than the average particle size of the silver powder are preferable, and (B) the maximum particle size of the silver powder. Resin particles having a large average particle diameter are more preferred. Furthermore, in order to suppress the deformation and distortion of the chip, monodisperse particles having high particle uniformity are preferable. In the present specification, monodisperse particles refer to particles having a uniform particle diameter, and refer to particles having a coefficient of variation (CV value) of 30% or less. This coefficient of variation (CV value) is preferably 20% or less, more preferably 10% or less.

  In addition, in the (D) resin particles, relatively small particles having an average particle diameter smaller than the average particle diameter of the silver powder (B) are preferable for suppressing the progress of the sintering. B) Relatively large particles having an average particle size larger than the average particle size of silver powder are preferred. Therefore, in order to obtain both effects, two types of particles having different average particle diameters can be used in combination as (D) resin particles. Thus, when two types of resin particles having different sizes are used, the resin particles having a large average particle diameter and the resin particles having a small average particle diameter are in a range of 10: 1 to 1:10 by mass ratio. It is preferable to use together.

  And (D) resin particle is 0.01-1 mass part, when the total amount of silver fine particles of (A) component and (B) component is 100 mass parts in a composition. Blended. When the component (D) is less than 0.01 parts by mass, the suppression of the sintering of silver particles does not function and the thermal shock resistance is also lowered, which is not preferable. In addition, when the amount exceeds 1 part by mass, in addition to the decrease in workability due to the increase in viscosity, the interfacial bonding force accompanying the increase in the volume of the organic component decreases, and accordingly, the high thermal conductivity cannot be ensured sufficiently and the heat dissipation performance decreases. .

  In the thermosetting resin composition of the present invention, in addition to the above-mentioned components, a low amount of a curing accelerator, rubber, silicone or the like generally blended in this type of composition as long as the effects of the present invention are not impaired. Stress agents, coupling agents, antifoaming agents, surfactants, colorants (pigments, dyes), various polymerization inhibitors, antioxidants, solvents, and other various additives may be added as necessary. it can. Each of these additives may be used alone or in combination of two or more.

  Such additives include silane coupling agents such as epoxy silane, mercapto silane, amino silane, alkyl silane, clade silane, vinyl silane, sulfide silane, titanate coupling agent, aluminum coupling agent, aluminum / zirconium coupling agent. Coupling agents such as carbon black, colorants such as carbon black, solid stress reducing components such as silicone oil and silicone rubber, and inorganic ion exchangers such as hydrotalcite.

  The thermosetting resin composition of the present invention includes the components (A) to (C) described above, components (D) to (F) blended as necessary, other additives such as coupling agents, solvents, and the like. Can be prepared by further kneading with a disperser, kneader, three-roll mill, etc., and then defoaming.

  The thermosetting resin composition of the present invention obtained in this way is excellent in high thermal conductivity and heat dissipation, and when used as a bonding material to a substrate of an element or a heat radiating member, the heat inside the device is transferred to the outside. Dispersibility is improved and product characteristics can be stabilized.

Next, the semiconductor device and electric / electronic parts of the present invention will be described.
The semiconductor device of the present invention is formed by adhering a semiconductor element onto a substrate serving as an element support member using the above-described thermosetting resin composition. That is, here, the thermosetting resin composition is used as a die attach paste.

  Here, the semiconductor element may be a known semiconductor element, and examples thereof include a transistor and a diode. Furthermore, examples of the semiconductor element include light emitting elements such as LEDs. The type of the light emitting element is not particularly limited. For example, a light emitting element in which a nitride semiconductor such as InN, AlN, GaN, InGaN, AlGaN, or InGaAlN is formed as a light emitting layer on a substrate by MOCVD or the like can be given. It is done. Examples of the element support member include copper, silver-plated copper, PPF (pre-plating lead frame), glass epoxy, and ceramics.

  By using the thermosetting resin composition of the present invention, a base material not subjected to metal plating can be bonded. In the semiconductor device thus obtained, the connection reliability with respect to the temperature cycle after mounting is drastically improved as compared with the conventional one. In addition, since the electrical resistance value is sufficiently small and the change with time is small, there is an advantage that the output does not decrease with time even when driving for a long time and the life is long.

  Moreover, the electric / electronic component of the present invention is formed by adhering a heat radiating member to a heat generating member using the above-described thermosetting resin composition. That is, here, the thermosetting resin composition is used as a heat radiating member bonding material.

  Here, the heat generating member may be the above-described semiconductor element, a member having the semiconductor element, or another heat generating member. Examples of the heat generating member other than the semiconductor element include an optical pickup and a power transistor. Examples of the heat radiating member include a heat sink and a heat spreader.

  Thus, by adhering the heat dissipation member to the heat generating member using the thermosetting resin composition described above, the heat generated by the heat generating member can be efficiently released to the outside by the heat dissipation member. Temperature rise can be suppressed. Note that the heat generating member and the heat radiating member may be directly bonded via a thermosetting resin composition, or may be indirectly bonded with another member having high thermal conductivity interposed therebetween.

  EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited to these Examples at all.

(Examples 1-11, Comparative Examples 1-3)
Each component was mixed according to the composition of Table 1 and Table 2, and kneaded with a roll to obtain a resin paste. The obtained resin paste was evaluated by the following method. The results are also shown in Table 1 and Table 2. In addition, the material as used in the Example and the comparative example used the commercial item as follows.

(A): Plate-type silver fine particles (manufactured by Toxen Industry Co., Ltd., trade name: M13; center particle diameter: 2 μm, thickness: 50 nm or less)
(A ′): spherical silver fine particles (manufactured by Mitsuboshi Belting Ltd., trade name: MDot; average particle diameter: 50 nm)
(B): Silver powder (Fukuda Metal Foil Powder Co., Ltd., trade name: AgC-212D; average particle size: 5 μm)
(C1): Hydroxyethylacrylamide (manufactured by Kojin Co., Ltd., HEAA)
(C2): Imide-expanded bismaleimide (manufactured by Designa Molecules, Inc., trade name: BMI-1500; number average molecular weight 1500)
(C3): diallyl bisphenol A diglycidyl ether type epoxy resin (manufactured by Nippon Kayaku Co., Ltd., trade name: RE-810NM; epoxy equivalent 223, hydrolyzable chlorine 150 ppm (1N KOH-ethanol, dioxane solvent, reflux 30 minutes)
Polymerization initiator: Dicumyl peroxide (manufactured by NOF Corporation, trade name: Park Mill D; decomposition temperature in rapid heating test: 126 ° C.)
(D): Malic acid (manufactured by Tokyo Chemical Industry Co., Ltd.)
(E): Diethylene glycol (manufactured by Tokyo Chemical Industry Co., Ltd.)
(F1): Spherical resin particles 1 (manufactured by Shin-Etsu Chemical Co., Ltd., trade name: KMP-600; average particle size: 1 μm, compression modulus (30% K value): 5300 N / mm ² , compression recovery rate: 100 %)
(F2): Spherical resin particles 2 (manufactured by Soken Chemical Co., Ltd., trade name: MX-1500; average particle size: 15 μm, compression modulus (30% K value): 1500 N / mm ² , compression recovery rate: 25% , CV value 2%)
(F3): Spherical resin particles 3 (manufactured by Sekisui Chemical Co., Ltd., trade name: Micropearl AUEZ-035A; average particle size: 35 μm, Au layer: 20 nm, intermediate Ni layer: 30 nm, compression modulus (30% K value) ): 1000 N / mm ² , compression recovery rate: 10%, CV value 5%)
(F4): Spherical resin particles 4 (manufactured by Sekisui Chemical Co., Ltd., trade name: Micropearl AUE-035A; average particle size: 35 μm, Au layer: 20 nm, intermediate Ni layer: 30 nm, compression modulus (30% K value) ): 4100 N / mm ² , compression recovery rate: 55%, CV value 5%)

<Evaluation method>
[viscosity]
The value at 25 ° C. and 5 rpm was measured using an E-type viscometer (3 ° cone).
[Pot life]
The number of days until the viscosity when the resin paste was left in a constant temperature bath at 25 ° C. increased 1.5 times or more of the initial viscosity was measured.

[Heat bond strength]
A backside gold chip provided with a gold vapor deposition layer on a 4 mm × 4 mm joining surface is mounted on a solid copper frame and PPF (Ni-Pd / Au plated copper frame) using a resin paste for semiconductor, and 200 ° C., Cured in 60 minutes. After curing and moisture absorption treatment (85 ° C., relative humidity 85%, 72 hours), the hot die shear strength at 260 ° C. was measured using a mount strength measuring device.

[Heat bond strength after high-temperature heat treatment]
The back gold chip provided with a gold vapor deposition layer on the 4 mm × 4 mm joining surface was mounted on a Mo substrate whose surface was Ni—Pd / Au plated using a semiconductor resin paste, and cured at 200 ° C. for 60 minutes. As high-temperature heat treatment, heat treatment (250 ° C. heat treatment, 100 hours and 1000 hours) and cooling cycle treatment (operation to raise the temperature from −40 ° C. to 250 ° C. and cool to −40 ° C. is one cycle, About each after 100 cycles and 1000 cycles), the die strength at the time of heating at 260 ° C. was measured using a mount strength measuring device.

[Thermal conductivity]
According to JIS R 1611-1997, the thermal conductivity of the cured product was measured by a laser flash method.
[Electric resistance]
The conductive paste was applied to a glass substrate (thickness 1 mm) to a thickness of 200 μm by screen printing and cured at 200 ° C. for 60 minutes. The electrical resistance of the obtained wiring was measured by a 4-terminal method using a product name “MCP-T600” (manufactured by Mitsubishi Chemical Corporation).

[Cold and thermal shock resistance]
Mounted on a copper frame and PPF using a resin paste obtained from a backside gold silicon chip provided with a gold vapor deposition layer on a 6 mm × 6 mm bonding surface, and heat-cured (HP curing at 200 ° C. for 60 seconds on a hot plate ) Or an oven, and heat curing (OV curing) at 200 ° C. for 60 minutes. This was subjected to a moisture absorption treatment at 85 ° C. and a relative humidity of 85% for 168 hours using an epoxy sealing material (trade name: KE-G3000D) manufactured by Kyocera Chemical Co., Ltd., followed by an IR reflow treatment ( 260 ° C., 10 seconds) and a cooling cycle treatment (the operation of raising the temperature from −55 ° C. to 150 ° C. and cooling to −55 ° C. as one cycle, which is 1000 cycles), and after each treatment, The number of internal cracks was observed with an ultrasonic microscope. The number of samples in which cracks occurred for five samples is shown.

Package: 80pQFP (14mm x 20mm x 2mm thickness)
Chip: Silicon chip and gold-plated chip on the back surface Lead frame: PPF and copper Molding of sealing material: 175 ° C., 2 minutes Post mold cure: 175 ° C., 8 hours

[Energization test]
A conductive paste is applied to an aluminum oxide substrate for a light-emitting device having a concave reflector structure on its side by a stamping method, a light-emitting element provided with a 600 μm-square silver deposited layer is mounted, and heat curing is performed at 200 ° C. for 60 minutes. went. Subsequently, the electrode of the light emitting element and the electrode of the substrate were wired with a gold wire and sealed with a silicone resin (manufactured by Shin-Etsu Chemical Co., Ltd.). In this state, a decrease in the reflectance with respect to the initial value after 500 hours, 1000 hours, and 2000 hours after the energization test (test condition 25 ° C., 50 mA) was calculated by the following formula.
(Reduction in reflectance with respect to the initial value) = (Reflectance after time t) ÷ (Initial reflectance)

[Void rate]
Observation using a microfocus X-ray inspection apparatus (SMX-1000, manufactured by Shimadzu Corporation), the void ratio is less than 5% “◯”, 5% to less than 8% “Δ”, and 8% or more “×”. ". The void ratio was calculated by the following equation by observing the solder joint from a direction perpendicular to the joint surface with an X-ray transmission device, obtaining the void area and the joint area.

Void ratio (%) = void area / (void area + joint area) × 100

[Chip distortion]
A backside gold chip provided with a gold vapor deposition layer on an 8 mm × 8 mm joint surface is mounted on a Mo substrate whose surface is Ni—Pd / Au plated using a semiconductor resin paste, and cured at 200 ° C. for 60 minutes. The package warpage of the manufactured semiconductor package was measured at room temperature. The measurement was performed in accordance with JEITA ED-7306 of the Japan Electronics and Information Technology Industries Association standard using a shadow moiré measuring device (Thermoire AXP: manufactured by Akrometrix). Specifically, a virtual plane calculated by the least square method of all data of the substrate surface in the measurement region is set as a reference plane, the maximum value in the vertical direction from the reference plane is A, and the minimum value is B The value of A | + | B | (Coplanarity) was taken as the package warpage value and evaluated as follows.
○: Less than 5 μm, Δ: 5 μm or more and less than 10 μm, ×: 10 μm or more

  From the above results, it was found that the thermosetting resin composition of the present invention was excellent in thermal conductivity, excellent in low stress property, excellent in adhesive properties and excellent in reflow peeling resistance. In addition, it was found that the generation of voids can be suppressed by containing resin particles, and that the use of specific resin particles is also effective in suppressing chip distortion. Therefore, by using this thermosetting resin composition as a die attach paste for element adhesion or a material for adhering heat dissipation members, a highly reliable semiconductor device and electric / electronic device can be obtained.

Claims (12)

(A) plate-type silver fine particles having a uniform thickness, (B) silver powder having an average particle size other than the component (A) of 0.5 to 30 μm, and (C) a thermosetting resin,
The (A) plate-type silver fine particles have one metal crystal plane grown, and the long side in the direction perpendicular to the thickness direction is in the range of 8 to 150 times the thickness,
When the total amount of the silver fine particles of the component (A) and the silver powder of the component (B) is 100 parts by mass, 1 to 20 parts by mass of the component (C) is blended. Resin composition. (A) plate-type silver fine particles having a uniform thickness, (B) silver powder having an average particle size other than the component (A) of 0.5 to 30 μm, and (C) a thermosetting resin,
(A) One surface of the plate-type silver fine particles is covered with a [111] surface,
When the total amount of the silver fine particles of the component (A) and the silver powder of the component (B) is 100 parts by mass, 1 to 20 parts by mass of the component (C) is blended. Resin composition. The thermosetting resin composition according to claim 1 or 2, wherein the (A) plate-type silver fine particles have a center particle diameter of 0.3 to 15 µm and a thickness of 10 to 200 nm. The thermosetting resin composition according to any one of claims 1 to 3 , wherein the (A) plate-type silver fine particles self-sinter at 100 ° C to 250 ° C. The thermosetting resin composition according to any one of claims 1 to 4 , wherein the (C) thermosetting resin is a cyanate resin, an epoxy resin, an acrylic resin, or a maleimide resin. The thermosetting resin composition according to any one of claims 1 to 5 , wherein a mass ratio of the component (A) to the component (B) is 10:90 to 90:10. The compound in which the component (C) is selected from the following general formulas (I) to (IV)

(In the formula, R ¹ represents a hydrogen atom or a methyl group, and R ² represents a divalent aliphatic hydrocarbon group having 1 to 100 carbon atoms or an aliphatic hydrocarbon group having a cyclic structure.)

(In the formula, R ¹ and R ² are the same as described above.)

(Wherein, ^{R 1} represents the same as above, n is an integer of 1 to 50.)

(Wherein R ¹ and n each represent the same as above)
The thermosetting resin composition according to any one of claims 1 to 6 , which is a compound containing a (meth) acryloyl group containing at least one of the following. Furthermore, when (D) flux is contained and the total amount of the silver fine particles of the component (A) and the silver powder of the component (B) is 100 parts by mass, the component (D) is 0.01 to 5 parts by mass. The thermosetting resin composition of any one of Claims 1 thru | or 7 mix | blended. Furthermore, when (E) a solvent is contained and the total amount of the silver fine particle of the said (A) component and the silver powder of the said (B) component is 100 mass parts, the said (E) solvent is mix | blended 7-20 mass parts. The thermosetting resin composition according to any one of claims 1 to 8 . 10. A semiconductor device, wherein the resin composition according to claim 1 is used as a die attach material, and a semiconductor element is bonded onto a substrate. The semiconductor device according to claim 10 , wherein the semiconductor element is a light emitting element. An electric / electronic device comprising the resin composition according to claim 1 as a heat radiating member bonding material, and the heat radiating member bonded to a heat-generating component.