CN102169856B

CN102169856B - Heat dissipation structure body

Info

Publication number: CN102169856B
Application number: CN201110034583.6A
Authority: CN
Inventors: 泉谷诚治; 原和孝; 福冈孝博; 内山寿惠; 平野仁嗣
Original assignee: Nitto Denko Corp
Current assignee: Nitto Denko Corp
Priority date: 2010-01-29
Filing date: 2011-01-30
Publication date: 2015-06-24
Anticipated expiration: 2031-01-30
Also published as: TW201139641A; KR20110089103A; US20110259565A1; CN104658994A; JP2012049496A; CN102169856A

Abstract

Provided is a heat dissipation structure body, comprising a substrate, an electronic part disposed on the substrate, a heat dissipation component used for dissipate heat generated by the electronic part, and a thermal conductive bonding sheet material disposed on the substrate in a manner of covering the electronic part. The thermal conductive bonding sheet material comprises a thermal conductive layer having sheet-shaped boron nitride particles. The heat conduction rate of the direction orthogonal with the thickness direction of the heat conductive layer is over 4W/m. the thermal conductive bonding sheet material contacts with the heat dissipation component.

Description

Heat-radiating structure

Technical field

The present invention relates to heat-radiating structure.

Background technology

In recent years, the electronic components such as memory are along with the thermal discharge increase produced during its work of high capacity, and electronic component has the possibility of deterioration thus, therefore comprise electronic component and need high-cooling property (high-termal conductivity) with the structure of the substrate installing it.

Such as propose following structure: on the multiple memories being installed on substrate, place the flat memory heat abstractor be made up of aluminium, with the structure (such as memory heat abstractor, with reference to the Internet (URL:http: //www.ainex.jp/products/hm-02.htm)) of fixture chucking substrate, each memory and memory heat abstractor.

In the structure of above-mentioned memory heat abstractor, the Internet, by the upper surface making memory heat abstractor be contacted with memory, the heat produced by memory is dispelled the heat by memory heat abstractor.

Summary of the invention

the problem that invention will solve

But, in the structure of above-mentioned memory heat abstractor, the Internet, the side surface of memory does not contact with flat memory heat abstractor, and, when the thickness of each memory is different, between the upper surface of the memory that thickness is thin and memory heat abstractor, produce gap.Therefore, the problem heat produced by memory can not being carried out fully heat radiation is had.

The object of the present invention is to provide the heat-radiating structure of thermal diffusivity excellence.

for the scheme of dealing with problems

Heat-radiating structure of the present invention, it is characterized in that, it possesses substrate, be installed on the electronic component of aforesaid base plate, for thermal diffusivity component that the heat produced by aforementioned electronic part is carried out dispelling the heat and with cover aforementioned electronic part mode be arranged at thermal conductivity adhesive sheet on aforesaid base plate, aforementioned thermal conductivity adhesive sheet possesses the thermal conductivity layer of the boron nitride particle containing sheet, the thermal conductivity in the direction orthogonal with the thickness direction of aforementioned thermal conductivity layer of aforementioned thermal conductivity layer is more than 4W/mK, aforementioned thermal conductivity adhesive sheet and aforementioned thermal diffusivity member contact.

In addition, in heat-radiating structure of the present invention, desirably, aforementioned thermal conductivity adhesive sheet possesses bond layer or the adhesive phase of at least one side being layered in aforementioned thermal conductivity layer, aforementioned bond layer or aforementioned adhesion oxidant layer bonding with aforesaid base plate or bond.

The effect of invention

In heat-radiating structure of the present invention, because electronic component is covered by thermal conductivity adhesive sheet, thus can by the heat that produced by electronic component from the upper surface of electronic component and side surface heat transfer to thermal conductivity adhesive sheet.Then, by described heat from thermal conductivity adhesive sheet heat transfer to radiating component, and can dispel the heat in radiating component to outside.

Therefore, it is possible to the heat produced by electronic component is dispelled the heat effectively by thermal conductivity adhesive sheet and radiating component.

Accompanying drawing explanation

Fig. 1 illustrates the sectional view of an execution mode of heat-radiating structure of the present invention.

Fig. 2 is the process chart of the manufacture method for illustration of thermal conductivity layer,

A () represents the operation of mixture or laminated sheet being carried out hot pressing,

B compacting sheet material is divided into multiple operations by () expression,

C () represents the folded operation of cutting plate sheet material layers.

Fig. 3 illustrates the stereogram of thermal conductivity layer.

Fig. 4 illustrates the sectional view of thermal conductivity adhesive sheet.

Fig. 5 is the process chart of the heat-radiating structure for construction drawing 1, represents to be fixed by the substrate being provided with electronic component on the housing that support framework, and prepares the operation of thermal conductivity adhesive sheet.

Fig. 6 illustrates the sectional view of other execution modes (form that thermal conductivity adhesive sheet is made up of thermal conductivity layer) of heat-radiating structure of the present invention.

Fig. 7 is the process chart of the heat-radiating structure for construction drawing 6, represents to be fixed by the substrate being provided with electronic component on the housing that support framework, and prepares the operation of thermal conductivity adhesive sheet.

Fig. 8 illustrates the sectional view of other execution modes (form of another ends contact housing of thermal conductivity adhesive sheet) of heat-radiating structure of the present invention.

Fig. 9 illustrates the sectional view of other execution modes (form that bonding adhesive layer contacts with electronic component upper surface) of heat-radiating structure of the present invention.

Figure 10 illustrates the stereogram of the experimental rig (before resistance to bend(ing) test) of the type i that resistance to bend(ing) is tested.

Figure 11 illustrates the stereogram of the experimental rig (in resistance to bend(ing) test) of the type i that resistance to bend(ing) is tested.

Embodiment

Fig. 1 illustrates the sectional view of an execution mode of heat-radiating structure of the present invention, Fig. 2 is the process chart of the manufacture method for illustration of thermal conductivity layer, Fig. 3 illustrates the stereogram of thermal conductivity layer, Fig. 4 illustrates the sectional view of thermal conductivity adhesive sheet, and Fig. 5 is the process chart of the heat-radiating structure for construction drawing 1.

In Fig. 1, this heat-radiating structure 1 possesses substrate 2, installs electronic component 3 on a substrate 2, for the framework 4 as thermal diffusivity component of the heat produced by electronic component 3 carried out dispelling the heat (Heat transmission, heat transfer) and the thermal conductivity adhesive sheet 5 that arranges on a substrate 2.

Substrate 2 is formed as roughly writing board shape, by the such as pottery such as aluminium nitride, aluminium oxide; Such as glass epoxy resin; The formation such as synthetic resin such as such as polyimides, polyamidoimide, acrylic resin, polyethers nitrile, polyether sulfone, PETG, PEN, polyvinyl chloride.

Electronic component 3 comprises such as IC (integrated circuit) chip 20, electric capacity 21, coil 22 and/or resistor 23.In addition, electronic component 3 controls such as be less than the voltage of 5V and/or be less than the electric current of 1A.Electronic component 3 is arranged on above substrate 2, in direction, face (direction, face of substrate 2, the left and right directions of Fig. 1 and depth direction.) on be arranged at intervals each other.The thickness of electronic component 3 is such as 1 μm ~ about 1cm.

The housing (not shown in FIG) that framework 4 is received substrate 2 supports, and its outside at substrate 2 (side) is arranged at intervals, and overlooks the roughly shaped as frame being formed as surrounding substrate 2.In addition, framework 4 is formed as from cross section long substantially rectangular of above-below direction.Framework 4 is formed by metals etc. such as such as aluminium, stainless steel, copper, iron.

Thermal conductivity adhesive sheet 5 is arranged on a substrate 2 in the mode of overlay electronic part 3.In addition, thermal conductivity adhesive sheet 5 is configured to an end (right part in Fig. 1) and contacts with the surface (upper surface and side surface) of electronic component 3, and another end (end, upper left in Fig. 1) contacts with the inner surface (right lateral surface) of framework 4.

Specifically, thermal conductivity adhesive sheet 5 Formation cross-section in heat-radiating structure 1 is roughly L-shaped, (central authorities of left and right directions) portion of central authorities and an end are configured to extend along direction, face on substrate 2, other end part from central portion bends upward from an end margin (left end edge) of substrate 2, and another end being configured to thermal conductivity adhesive sheet 5 extends upward in the right lateral surface (inner surface) of framework 4.

This thermal conductivity adhesive sheet 5 possess thermal conductivity layer 6 like that with reference to Fig. 4 and be laminated in the bond layer 7 at the back side (below) of thermal conductivity layer 6 or adhesive phase 7 (following, sometimes they are referred to as " bonding adhesive layer 7 ".)。

Thermal conductivity layer 6 is formed as sheet, and containing boron nitride particle.

Specifically, thermal conductivity layer 6 as neccessary composition, further, such as, contains resinous principle containing boron nitride (BN) particle.

Boron nitride particle is formed as sheet (or flakey), to be oriented in the form dispersion of prescribed direction (aftermentioned) in thermal conductivity layer 6.

The average of longitudinal direction length (maximum length in the direction orthogonal with the thickness direction of sheet) of boron nitride particle is such as 1 ~ 100 μm, preferably 3 ~ 90 μm.In addition, the average out to of the longitudinal direction length of boron nitride particle more than 5 μm, is preferably more than 10 μm, more preferably more than 20 μm, be especially preferably more than 30 μm, most preferably be more than 40 μm, usually be such as less than 100 μm, be preferably less than 90 μm.

In addition, the average of thickness (the thickness direction length of sheet material, that is, the horizontal direction length of particle) of boron nitride particle is such as 0.01 ~ 20 μm, preferably 0.1 ~ 15 μm.

In addition, the aspect ratio (longitudinal direction length/thickness) of boron nitride particle is such as 2 ~ 10000, is preferably 10 ~ 5000.

Then, the average grain diameter by light scattering determining of boron nitride particle is such as more than 5 μm, is preferably more than 10 μm, more preferably more than 20 μm, especially preferably more than 30 μm, most preferably is more than 40 μm, is generally less than 100 μm.

In addition, by the average grain diameter of light scattering determining be the volume average particle size measured by dynamic light scattering formula particle size distribution device.

When the average grain diameter by light scattering determining of boron nitride particle does not meet above-mentioned scope, sometimes thermal conductivity layer 6 become fragile, treatability reduce.

In addition, the bulk density (JIS K 5101, apparent density) of boron nitride particle is such as 0.3 ~ 1.5g/cm ³, be preferably 0.5 ~ 1.0g/cm ³.

In addition, boron nitride particle can use the processed goods that commercially available product or its processing obtain.As the commercially available product of boron nitride particle, " PT " series (such as " PT-110 " etc.) that such as MomentivePerformance Materials Japan LCC manufactures can be listed, " SHOBN UHP " series (such as " SHOBN UHP-1 " etc.) that Showa electrician company manufactures etc.

Resinous principle is the material that can disperse boron nitride particle, that is, disperse the dispersion solvent (matrix) of boron nitride particle, can list the resinous principles such as such as heat-curing resin composition, thermoplastic resin elements.

As heat-curing resin composition, such as epoxy resin, Thermocurable polyimides, phenolic resins, urea resin, melmac, unsaturated polyester resin, diallyl phthalate resin, organic siliconresin, Thermocurable polyurethane resin etc. can be listed.

As thermoplastic resin elements, such as polyolefin (such as polyethylene can be listed, polypropylene, ethylene-propylene copolymer etc.), acrylic resin (such as polymethyl methacrylate etc.), polyvinyl acetate, ethylene-vinyl acetate copolymer, polyvinyl chloride, polystyrene, polyacrylonitrile, polyamide, Merlon, polyacetals, PETG, polyphenylene oxide, polyphenylene sulfide, polysulfones, polyether sulfone, polyether-ether-ketone, polyallyl sulfone (poly allyl sulfone), thermoplastic polyimide, TPU(Thermoplastic polyurethanes), PABM, polyamidoimide, Polyetherimide, bismaleimide-triazine resin, polymethylpentene, fluoride resin, liquid crystal polymer, olefin-vinyl alcohol copolymer, ionomer, polyarylate, acrylonitrile ethylene styrene copolymer, acrylonitrile-butadiene-styrene copolymer, acrylonitritrile-styrene resin etc.

These resinous principles may be used singly or two or more in combination.

In resinous principle, preferably list epoxy resin.

Epoxy resin normal temperature be liquid, semisolid and solid-state in arbitrary form.

Specifically, as epoxy resin, such as bisphenol-type epoxy resin (such as bisphenol A type epoxy resin can be listed, bisphenol f type epoxy resin, bisphenol-s epoxy resin, bisphenol-A epoxy resin, dimer acid modified bisphenol-type epoxy resin etc.), phenolic novolac (novolac) type epoxy resin (such as phenol novolak type epoxy resin, cresol novolak type epoxy resin, biphenyl type epoxy resin etc.), naphthalene type epoxy resin, fluorenes type epoxy resin (such as two aryl fluorenes type epoxy resin etc.), the fragrant family epoxy resin such as triphenylmethane type epoxy resin (such as trihydroxy benzene methane type epoxy resin etc.), such as three epoxypropyl isocyanuric acid esters (triglycidyl group isocyanuric acid ester), hydantoin epoxy resin etc. are containing azo-cycle epoxy resin, such as aliphat type epoxy resin, such as alicyclic type epoxy resin (such as the ring-like epoxy resin of dicyclo etc.), such as diglycidyl ether type epoxy resin, such as glycidyl amine type epoxy resin etc.

These epoxy resin may be used singly or two or more in combination.

Preferably list the combination of liquid-state epoxy resin and solid epoxy resin, preferably list liquid fragrant family epoxy resin and the combination etc. of solid-state fragrant family epoxy resin further.As such combination, specifically, the combination of liquid bisphenol-type epoxy resin and solid-state triphenylmethane type epoxy resin, the bisphenol-type epoxy resin of liquid state and the combination of solid-state bisphenol-type epoxy resin can be listed.

In addition, as epoxy resin, preference is enumerated and is used alone semi-solid epoxy resin, preferably lists further and is used alone semi-solid fragrant family epoxy resin.As such epoxy resin, semi-solid fluorenes type epoxy resin specifically can be listed.

If be liquid epoxy resin and the combination of solid-state epoxy resin, semi-solid epoxy resin, then can improve the difference in height tracing ability (aftermentioned) of thermal conductivity layer 6.

In addition, the epoxide equivalent of epoxy resin is such as 100 ~ 1000g/eqiv., is preferably 160 ~ 700g/eqiv.; Softening temperature (ring and ball method) is such as less than 80 DEG C (being specifically 20 ~ 80 DEG C), is preferably less than 70 DEG C (being specifically 25 ~ 70 DEG C).

In addition, the melt viscosity of epoxy resin at 80 DEG C is such as 10 ~ 20000mPas, is preferably 50 ~ 15000mPas.When combinationally using two or more epoxy resin, the melt viscosity as their mixture is set in above-mentioned scope.

In addition, combinationally use under normal temperature under solid-state epoxy resin and normal temperature for liquid epoxy resin time, combinationally use softening temperature such as being less than 45 DEG C, be preferably that the 1st epoxy resin of less than 35 DEG C and softening temperature are such as more than 45 DEG C, preferably the 2nd epoxy resin of more than 55 DEG C.Thereby, it is possible to the kinematic viscosity (according to JIS K 7233, aftermentioned) of resinous principle (mixture) to be set in the scope of hope, in addition, the difference in height tracing ability of thermal conductivity layer 6 can be improved.

In addition, epoxy resin can be made to contain such as curing agent and curing accelerator and prepare as composition epoxy resin.

Curing agent is by heating the potentiality curing agent (epoxy curing agent) making epoxy resin cure, can list such as imidazolium compounds, amines, anhydride compound, amide compound, hydrazide compound, imidazolinium compounds etc.In addition, in addition to the foregoing, phenolic compounds, urea compounds, polythiaether compound etc. can also be listed.

As imidazolium compounds, such as 2-phenylimidazole, glyoxal ethyline, 2-ethyl-4-methylimidazole, 2 phenyl 4 methyl 5 hydroxy methylimidazole etc. can be listed.

As amines, the aliphatic polyamines such as such as ethylenediamine, propane diamine, diethylenetriamines, trien can be listed; The aromatic polyamines etc. such as such as m-phenylene diamine (MPD), diaminodiphenyl-methane, diamino diphenyl sulfone.

As anhydride compound, such as phthalic anhydride, maleic anhydride, tetrabydrophthalic anhydride, hexahydrophthalic anhydride, 4-methyl-hexahydrophthalic anhydride, methylnadic anhydride (methyl nadic anhydride), PMA, dodecenylsuccinic anhydride, dichlorosuccinic acid acid anhydride, benzophenone tetracarboxylic anhydride, chlorendic anhydride (chlorendic anhydride) etc. can be listed.

As amide compound, such as dicyandiamide, polyamide etc. can be listed.

As hydrazide compound, such as adipic dihydrazide etc. can be listed.

As imidazolinium compounds, such as methylimidazole quinoline, 2-ethyl-4-methylimidazole quinoline, ethyl imidazol(e) quinoline, isopropylimdazole quinoline, 2,4-methylimidazole quinolines, benzylimidazoline, undecyl imidazole quinoline, heptadecyl imidazole quinoline, 2-phenyl-4-methylimidazole quinoline etc. can be listed.

These curing agent may be used singly or two or more in combination.

As curing agent, preferably list imidazolium compounds.

As curing accelerator, the such as tertiary amine compound such as triethylenediamine, three-2,4,6-dimethylaminomethyl phenol can be listed; The phosphorus compounds such as such as triphenylphosphine, tetraphenylboronic acid tetraphenylphosphoniphenolate, O, O-diethyldithioposphoric acid Si Zheng Ding Ji Phosphonium; Such as quarternary ammonium salt compound, organometalate compound, their derivative etc.These curing accelerators may be used singly or two or more in combination.

Relative to 100 mass parts epoxy resin, the mixing ratio of the curing agent in composition epoxy resin is such as 0.5 ~ 50 mass parts, is preferably 1 ~ 10 mass parts; The mixing ratio of curing accelerator is such as 0.1 ~ 10 mass parts, is preferably 0.2 ~ 5 mass parts.

Above-mentioned curing agent and/or curing accelerator can be prepared as the solvent solution utilizing solvent to carry out dissolving and/or disperseing and/or solvent dispersions and use as required.

As solvent, the such as organic solvents etc. such as amide-type such as ester class, such as DMF such as ketone, such as ethyl acetate such as acetone, methylethylketone (MEK) can be listed.In addition, as solvent, the such as water solvents such as alcohols such as water, such as methyl alcohol, ethanol, propyl alcohol, isopropyl alcohol also can be listed.As solvent, preferably list organic solvent, more preferably ketone, amide-type.

In addition, movement viscosity test (the temperature: 25 DEG C ± 0.5 DEG C by foundation JIS K 7233 (bubble viscometer method) of resinous principle, solvent: butyl carbitol, resinous principle (solid constituent) concentration: 40 quality %) kinematic viscosity that measures is such as 0.22 × 10 ^-4~ 2.00 × 10 ^-4m ²/ s, preferably 0.3 × 10 ^-4~ 1.9 × 10 ^-4m ²/ s, further preferably 0.4 × 10 ^-4~ 1.8 × 10 ^-4m ²/ s.In addition, above-mentioned kinematic viscosity also can set is such as 0.22 × 10 ^-4~ 1.00 × 10 ^-4m ²/ s, preferably 0.3 × 10 ^-4~ 0.9 × 10 ^-4m ²/ s, more preferably 0.4 × 10 ^-4~ 0.8 × 10 ^-4m ²/ s.

When the kinematic viscosity of resinous principle exceedes above-mentioned scope, sometimes cannot give thermal conductivity layer 6 with the flexibility of excellence and difference in height tracing ability (aftermentioned).On the other hand, when the kinematic viscosity of resinous principle does not meet above-mentioned scope, boron nitride particle sometimes can not be made along prescribed direction orientation.

In addition, in the movement viscosity test according to JIS K 7233 (air bubble viscometer method), by the rate of climb of steeping in resinous principle sample compared with the rate of climb of steeping in standard sample (kinematic viscosity is known), the kinematic viscosity of standard sample consistent for the rate of climb is judged to be the kinematic viscosity of resinous principle, by measuring the kinematic viscosity of resinous principle like this.

Then, in thermal conductivity layer 6, boron nitride particle in volume be benchmark containing proportional (solid constituent, that is, boron nitride particle is relative to the percentage by volume of the cumulative volume of resinous principle and boron nitride particle) be such as 35 more than volume %, be preferably 60 more than volume %, be preferably 65 more than volume %; Usually be such as 95 below volume %, be preferably 90 below volume %.

Boron nitride particle in volume be benchmark containing proportional discontented foot above-mentioned scope time, sometimes can not make boron nitride particle in thermal conductivity layer 6 along prescribed direction orientation.On the other hand, boron nitride particle in volume be benchmark containing proportional exceed above-mentioned scope time, thermal conductivity layer 6 becomes fragile sometimes, treatability reduce.

In addition, relative to formed thermal conductivity layer 6 each composition (boron nitride particle and resinous principle) total amount (solid constituent total amount) 100 mass parts, boron nitride particle be that the mixing ratio of benchmark is such as 40 ~ 95 mass parts, is preferably 65 ~ 90 mass parts in quality; Relative to formed thermal conductivity layer 6 each composition total amount 100 mass parts, resinous principle be that the mixing ratio of benchmark is such as 5 ~ 60 mass parts, is preferably 10 ~ 35 quality in quality.In addition, boron nitride particle relative to 100 mass parts resinous principles take quality as the mixing ratio of benchmark be such as 60 ~ 1900 mass parts, be preferably 185 ~ 900 mass parts.

In addition, when combinationally using two kinds of epoxy resin (the 1st epoxy resin and the 2nd epoxy resin), the mass ratio (quality of quality/the 2nd epoxy resin of the 1st epoxy resin) of the 1st epoxy resin and the 2nd epoxy resin can set aptly according to the softening temperature etc. of each epoxy resin (the 1st epoxy resin and the 2nd epoxy resin), such as, be 1/99 ~ 99/1, be preferably 10/90 ~ 90/10.

In addition, in resinous principle, except above-mentioned each composition (polymer), comprise such as polymer precursor (such as, comprising the low-molecular weight polymer etc. of oligomer) and/or monomer.

Then, the formation method of thermal conductivity layer 6 is described.

In the method, first, above-mentioned each composition is coordinated with above-mentioned mixing ratio, and is uniformly mixed, prepare mixture thus.

In being uniformly mixed, each composition should be mixed effectively, such as, solvent and above-mentioned each composition can be mixed together or such as can make resinous principle (preferred thermoplastic resin composition) melting by heating.

As solvent, organic solvent similar to the above can be listed.In addition, when above-mentioned curing agent and/or curing accelerator are prepared as solvent solution and/or solvent dispersions, solvent can not added in being uniformly mixed, and the solvent former state of solvent solution and/or solvent dispersions is provided as the mixed solvent being used for being uniformly mixed.Or, also in being uniformly mixed, solvent can be added as mixed solvent further.

When using solvent to be uniformly mixed, after being uniformly mixed, solvent is removed.

For the removing of solvent, such as, at room temperature place 1 ~ 48 hour, or such as heat 0.5 ~ 3 hour at 40 ~ 100 DEG C, or such as heat 0.5 ~ 3 hour at 20 ~ 60 DEG C under the reduced atmosphere of 0.001 ~ 50kPa.

When making resinous principle melting by heating, heating-up temperature is such as near the softening temperature of resinous principle or exceedes this temperature, is specifically 40 ~ 150 DEG C, is preferably 70 ~ 140 DEG C.

Then, in the method hot pressing is carried out to gained mixture.

Specifically, as shown in (a) of Fig. 2, such as, carry out hot pressing by 2 mold release film (mold release film), 12 pairs of mixtures as required, obtain compacting sheet material 6A thus.The condition of hot pressing is as follows: temperature is such as 50 ~ 150 DEG C, is preferably 60 ~ 140 DEG C; Pressure is such as 1 ~ 100MPa, is preferably 5 ~ 50MPa; Time is such as 0.1 ~ 100 minute, is preferably 1 ~ 30 minute.

Preferred further vacuum hotpressing is carried out to mixture.The vacuum degree of vacuum hotpressing is such as 1 ~ 100Pa, is preferably 5 ~ 50Pa; Temperature and pressure and time, identical with those of above-mentioned hot pressing.

When temperature in hot pressing, pressure and/or time are beyond above-mentioned scope, the porosity P (aftermentioned) of thermal conductivity layer 6 cannot be adjusted to desired value sometimes.

The thickness of the compacting sheet material 6A obtained by hot pressing is such as 50 ~ 1000 μm, is preferably 100 ~ 800 μm.

Then, in the method, as shown in (b) of Fig. 2, compacting sheet material 6A be divided into multiple (such as 4) and obtain cutting plate material 6B (segmentation process).In the segmentation of compacting sheet material 6A, compacting sheet material 6A is cut along its thickness direction, is split into multiple when through-thickness is projected.In addition, the mode becoming same shape when suppressing sheet material 6A to make each segmentation sheet material 6B through-thickness project is cut.

Then, in the method, as shown in (c) of Fig. 2, by stacked in a thickness direction for each segmentation sheet material 6B, laminated sheet 6C (lamination process) is obtained.

Thereafter, in the method, as shown in (a) of Fig. 2, by laminated sheet 6C hot pressing (preferred vacuum hotpressing) (hot pressing process).The condition of hot pressing is identical with the hot pressing condition of said mixture.

The thickness of the laminated sheet 6C after hot pressing is such as below 1mm, is preferably below 0.8mm; Usually, be such as more than 0.05mm, preferably more than 0.1mm.

Thereafter, with reference to shown in Fig. 3, in order to make boron nitride particle 8 in resinous principle 9 effectively along prescribed direction orientation in thermal conductivity layer 6, repeatedly implement the series of processes of above-mentioned segmentation process ((b) of Fig. 2), lamination process ((c) of Fig. 2) and hot pressing process ((a) of Fig. 2).For the number of occurrence, there is no particular limitation, can set aptly according to the occupied state of boron nitride particle, such as, be 1 ~ 10 time, be preferably 2 ~ 7 times.

In addition, in above-mentioned hot pressing process ((a) of Fig. 2), such as, by multiple stacks etc., mixture and laminated sheet 6C can be rolled.

Thereby, it is possible to form the thermal conductivity layer 6 shown in Fig. 3 and Fig. 4.

The thickness of the thermal conductivity layer 6 formed is such as below 1mm, is preferably below 0.8mm; Usually, be such as more than 0.05mm, preferably more than 0.1mm.

In addition, boron nitride particle 8 in thermal conductivity layer 6 in volume be benchmark containing proportional (solid constituent, namely, boron nitride particle 8 is relative to the percentage by volume of the cumulative volume of resinous principle 9 and boron nitride particle 8) as mentioned above, such as, be 35 more than volume % (being preferably 60 more than volume %, more preferably 75 more than volume %); Be generally 95 below volume % (being preferably 90 below volume %).

Boron nitride particle 8 containing proportional discontented foot above-mentioned scope time, sometimes can not make boron nitride particle 8 in thermal conductivity layer 6 along prescribed direction orientation.

In addition, when resinous principle 9 is heat-curing resin composition, such as, repeatedly implement the series of processes of above-mentioned segmentation process ((b) of Fig. 2), lamination process ((c) of Fig. 2) and hot pressing process ((a) of Fig. 2) in the uncured state, former state obtains the thermal conductivity layer 6 of its uncured state.In addition, thermal conductivity adhesive sheet 5 relative to electronic component 3 and substrate 2 bonding time, make thermal conductivity layer 6 hot curing of its uncured state.

Then, in the thermal conductivity layer 6 formed like this, as shown in Fig. 3 and close-up schematic view thereof, the longitudinal direction LD of boron nitride particle 8 intersects direction, the face SD orientation of (orthogonal) along with the thickness direction TD of thermal conductivity layer 6.

In addition, the arithmetic average (boron nitride particle 8 is relative to the orientation angles α of thermal conductivity layer 6) of the longitudinal direction LD of boron nitride particle 8 and direction, the face SD angulation of thermal conductivity layer 6 is such as less than 25 degree, is preferably less than 20 degree; Be generally more than 0 degree.

In addition, boron nitride particle 8 calculates as follows relative to the orientation angles α of thermal conductivity layer 6: utilize Cross section polishing instrument (CP) that thermal conductivity layer 6 through-thickness is carried out cutting processing, use scanning electron microscopy (SEM) to the cross section occurred thus can observe more than 200 boron nitride particle 8 the visual field multiplying power under take pictures, according to gained SEM photo, obtain the inclined angle alpha of longitudinal direction LD relative to direction, the face SD (direction orthogonal with thickness direction TD) of thermal conductivity layer 6 of boron nitride particle 8, and calculate its mean value.

Thus, the thermal conductivity of direction, the face SD of thermal conductivity layer 6 is more than 4W/mK, is preferably more than 5W/mK, is more preferably more than 10W/mK, more preferably more than 15W/mK, is especially preferably more than 25W/mK, is generally below 200W/mK.

In addition, when resinous principle 9 is heat-curing resin composition, the thermal conductivity of direction, the face SD of thermal conductivity layer 6 is substantially identical in the front and back of hot curing.

When the thermal conductivity of direction, the face SD of thermal conductivity layer 6 does not meet above-mentioned scope, because the thermal conductivity of direction, face SD is insufficient, therefore sometimes can not use in the heat radiation purposes of the thermal conductivity of direction, face SD in this needs.

In addition, the thermal conductivity of direction, the face SD of thermal conductivity layer 6 is measured by PULSE HEATING method.Xenon flash lamp analyzer (xenon flashanalyzer) " LFA-447 type " (manufacture of NETZSCH company) can be used in PULSE HEATING method.

In addition, the thermal conductivity of the thickness direction TD of thermal conductivity layer 6 is such as 0.5 ~ 15W/mK, is preferably 1 ~ 10W/mK.

In addition, the thermal conductivity of the thickness direction TD of thermal conductivity layer 6 can pass through PULSE HEATING method, laser flash method or TWA method (temperature wave analysis) mensuration.In PULSE HEATING method, equipment same as described above can be used; In laser flash method, " TC-9000 " (ULVAC-RIKO, Inc. manufacture) can be used, in TWA method, " ai-Phase mobiLe " (manufacture of ai-Phase Co., Ltd.) can be used.

Thus, the thermal conductivity of direction, face SD of thermal conductivity layer 6 and the ratio (thermal conductivity of the thermal conductivity/thickness direction TD of direction, face SD) of the thermal conductivity of the thickness direction TD of thermal conductivity layer 6 are such as more than 1.5, are preferably more than 3, more preferably more than 4; Be generally less than 20.

In addition, although not shown in figure 3, in thermal conductivity layer 6, such as, hole (gap) is had to be formed.

The ratio of the hole in thermal conductivity layer 6 and porosity P can by boron nitride particle 8 containing proportional (taking volume as benchmark), and then the temperature of the hot pressing of the mixture of boron nitride particle 8 and resinous principle 9 ((a) of Fig. 2), pressure and/or time adjust, specifically, can adjust by the temperature of above-mentioned hot pressing ((a) of Fig. 2), pressure and/or time are set in above-mentioned scope.

Porosity P in thermal conductivity layer 6 is such as 30 below volume %, is preferably 10 below volume %.

Above-mentioned porosity P such as can be measured by following method: first, utilize Cross section polishing instrument (CP) that thermal conductivity layer 6 through-thickness is carried out cutting processing, the cross section scanning electron microscopy (SEM) occurred thus is observed under 200 times, obtain image, by gained image, binary conversion treatment is carried out to aperture sections and remainder, then calculates the area ratio that aperture sections is long-pending relative to the overall sectional of thermal conductivity layer 6.

In addition, in thermal conductivity layer 6, be such as less than 100% relative to the porosity P1 before solidification, the porosity P2 after solidification, be specifically preferably less than 50%.

In the mensuration of porosity P (P1), when resinous principle 9 is heat-curing resin composition, use the thermal conductivity layer 6 before hot curing.

If the porosity P of thermal conductivity layer 6 is in above-mentioned scope, then can improve the difference in height tracing ability (aftermentioned) of thermal conductivity layer 6.

In addition, thermal conductivity layer 6, in the resistance to bend(ing) test being foundation with the cylindrical mandrel method of JIS K 5600-5-1 (mandrel method), when evaluating under following experimental condition, does not preferably observe fracture.

Experimental condition

Experimental rig: type i

Axle: diameter 10mm

Angle of bend: more than 90 degree

The thickness of thermal conductivity layer 6: 0.3mm

In addition, Figure 10 and Figure 11 illustrates the stereogram of the experimental rig of type i, below, the experimental rig of type i is described.

In Figure 10 and Figure 11, the experimental rig 90 of type i comprises: the first flat board 91; Second flat board 92, itself and the first flat board 91 configure side by side; And axle (rotating shaft) 93, it is arranged to make the first dull and stereotyped 91 and second flat board 92 relatively rotate.

First flat board 91 is formed as substantially rectangular tabular.In addition, an end (movable end) of the first flat board 91 is provided with stop part 94.Stop part 94 is formed on the surface of the first flat board 91 in the mode extended along an end of the first flat board 91.

Second flat board 92 tabular in the form of a substantially rectangular configures in its mode adjacent with the first flat board 91 (one side of the other end (base end part) of the side contrary with the end being provided with stop part 94).

Axle 93 is with dull and stereotyped 92 adjacent one another are while the mode extended is formed along first dull and stereotyped 91 and second.

As shown in Figure 10, before the test of beginning resistance to bend(ing), the surface of the first flat board 91 of the experimental rig 90 of the type I and the surface of the second flat board 92 is made to be in same plane.

Further, when implementing resistance to bend(ing) test, thermal conductivity layer 6 is positioned on the surface of the first flat board 91 and the surface of the second flat board 92.In addition, thermal conductivity layer 6 is that the mode abutted with stop part 94 with it loads.

Then, as shown in figure 11, the first dull and stereotyped 91 and second flat board 92 is made to relatively rotate.Specifically, the movable end of the movable end of the first flat board 91 and the second flat board 92 is made to rotate predetermined angular centered by axle 93.In detail, make first dull and stereotyped 91 with the second flat board 92 first dull and stereotyped 91 being close with the surface of the movable end of the second flat board 92 (relative to) mode rotate.

Thus, thermal conductivity layer 6 is bending centered by axle 93 while the rotation of following the first dull and stereotyped 91 and second flat board 92.

More preferably, fracture is not observed when angle of bend is set as 180 degree by thermal conductivity layer 6 under these experimental conditions yet.

In addition, when resinous principle 9 is heat-curing resin composition, the thermal conductivity layer 6 being provided in pliability test is the thermal conductivity layer 6 of semi-solid preparation (B-stage state).

In resistance to bend(ing) test under above-mentioned angle of bend, observe thermal conductivity layer 6 when rupturing, sometimes can not give the flexibility of thermal conductivity layer 6 excellence.

In addition, this thermal conductivity layer 6 with JIS K 7171 (2008) in the three point bending test of foundation, when evaluating with following experimental condition, such as, do not observe fracture.

Experimental condition

Test film: size 20mm × 15mm

Distance between the fulcrum: 5mm

Test speed: 20mm/min (the pressing down speed of pressure head)

Angle of bend: 120 degree

Whether evaluation method: when testing at the conditions of the experiments described above, have the fractures such as crackle by the central portion of visualization experiment slice.

In addition, in three point bending test, when resinous principle 3 is heat-curing resin composition, use the thermal conductivity layer 6 before hot curing.

Then, this thermal conductivity layer 6 does not observe fracture in above-mentioned three point bending test, and therefore known difference in height tracing ability is excellent.In addition, difference in height tracing ability refers to, thermal conductivity layer 6 is arranged at difference in height object (such as aforesaid substrate 2 etc.) are set time, this difference in height (difference in height such as formed by above-mentioned electronic component 3) can be followed and carry out closely sealed characteristic.

In addition, such as can with the mark such as word, mark at thermal conductivity layer 6.That is, the mark tack of thermal conductivity layer 6 is excellent.Mark tack refers to the characteristic that above-mentioned mark reliably can be attached on thermal conductivity layer 6.

As mark, specifically, can by printing or marking etc. and be attached to thermal conductivity layer 6 (coating, fixing or set).

As printing, such as ink jet printing, letterpress, intaglio printing, laser printing etc. can be listed.

In addition, when carrying out typographic(al) mark by ink jet printing, letterpress or intaglio printing, such as, fixing for the ink being used for the fixation performance improving mark layer can be arranged at the surface (printed side surface, upper surface, opposite side surfaces relative to bonding adhesive phase 7) of thermal conductivity layer 6.

In addition, when carrying out typographic(al) mark by laser printing, such as, the toner fixing layer being used for the fixation performance improving mark can be arranged at the surface (printed side surface, upper surface, opposite side surfaces relative to bonding adhesive phase 7) of thermal conductivity layer 6.

As marking, such as laser beam marking, punching press etc. can be listed.

In addition, thermal conductivity layer 6 has insulating properties and adhesiveness (microviscosity).

Specifically, the volume resistance (JIS K6271) of thermal conductivity layer 6 is such as 1 × 10 ¹⁰more than Ω cm, preferably 1 × 10 ¹²more than Ω cm; Be generally 1 × 10 ²⁰below Ω cm.

The volume resistance R of thermal conductivity layer 6 measures according to JIS K 6911 (Thermocurable plastics ordinary test method, version in 2006).

When the volume resistance R of thermal conductivity layer 6 does not meet above-mentioned scope, sometimes can not prevent the short circuit between electronic component described later.

In addition, in thermal conductivity layer 6, when resinous principle 9 is heat-curing resin composition, volume resistance R is the value of the thermal conductivity layer 6 after solidification.

In addition, thermal conductivity layer 6 in following initial bonding force test (1), such as, does not come off from adherend.That is, thermal conductivity layer 6 and adherend keep temporal hold state.

Initial bonding force test (1): add thermo-compressed thermal conductivity layer 6 and carry out temporary fixed on adherend in the horizontal direction, place after 10 minutes, adherend is reversed up and down.

As adherend, the such as above-mentioned substrate 2 etc. being provided with electronic component can be listed.Crimping such as, makes the sponge roller limit formed by resins such as organic siliconresins press the surface scrolls of thermal conductivity layer 6 limit at thermal conductivity layer 6.

In addition, when resinous principle 9 is heat-curing resin composition (such as epoxy resin), the temperature adding thermo-compressed is such as 80 DEG C.

On the other hand, when resinous principle 9 is thermoplastic resin elements (such as polyethylene), the temperature adding thermo-compressed such as the softening point of thermoplastic resin elements or fusing point add the temperature of 10 ~ 30 DEG C, the softening point being preferably thermoplastic resin elements or fusing point add the softening point of temperature, the more preferably thermoplastic resin elements of 15 ~ 25 DEG C or fusing point add 20 DEG C temperature, be specifically 120 DEG C (namely, the softening point of thermoplastic resin elements or fusing point are 100 DEG C, and these 100 DEG C add the temperature of 20 DEG C).

When thermal conductivity layer 6 comes off from adherend in above-mentioned initial bonding force test (1), that is, when thermal conductivity layer 6 and adherend temporal hold state can not be kept, sometimes thermal conductivity layer 6 reliably can not be temporarily fixed on adherend.

In addition, when resinous principle 9 is heat-curing resin composition, thermal conductivity layer 6 for initial bonding force test (1) and initial bonding force test (2) (aftermentioned) is uncured thermal conductivity layer 6, tested by initial bonding force test (1) and initial bonding force and add thermo-compressed in (2), thermal conductivity layer 6 becomes B-stage state thus.

In addition, when resinous principle 9 is thermoplastic resin elements, thermal conductivity layer 6 for initial bonding force test (1) and initial bonding force test (2) (aftermentioned) is solid-state thermal conductivity layer 6, makes thermal conductivity layer 6 be soft state by the thermo-compressed that adds in initial bonding force test (1) and initial bonding force test (2).

Preferably, thermal conductivity layer 6 does not come off from adherend in both above-mentioned initial bonding force test (1) and following initial bonding force test (2).That is, the temporal hold state of thermal conductivity layer 6 and adherend can be kept.

Initial bonding force test (2): thermal conductivity layer 6 heating be crimped on adherend in the horizontal direction and carry out temporary fixed, placing 10 minutes, then make adherend vertically (above-below direction) configuration.

The temperature added in thermo-compressed of initial bonding force test (2) is identical with the temperature added in thermo-compressed that above-mentioned initial bonding force tests (1).

Bonding adhesive layer 7 is formed at the back side of thermal conductivity layer 6 as shown in Figure 4.Specifically, bonding adhesive layer 7 be formed at as shown in Figure 1 towards the substrate 2 exposed from electronic component 3, below thermal conductivity layer 6.

Bonding adhesive layer 7 has flexibility and has cementability or adhesiveness (viscosity) in normal temperature atmosphere and heating atmosphere, be made up of the bonding agent that can be shown bonding effect by the cooling after heating or heating or the adhesive that can show adhesive effect (effect of bonding, the i.e. effect of pressure-sensitive adhesive).

As bonding agent, such as heat curable adhesive, heat molten type bonding agent etc. can be listed.

Heat curable adhesive is by solidifying by heating the hot curing caused, on a substrate 2 bonding.As heat curable adhesive, such as epoxy heat curable adhesive, polyurethane series heat curable adhesive, acrylic acid series heat curable adhesive etc. can be listed.Preferably list epoxy heat curable adhesive.

The curing temperature of heat curable adhesive is such as 100 ~ 200 DEG C.

There is melting by heating or soften and be heat fused in substrate 2 in heat molten type bonding agent, is solidified by cooling thereafter, on a substrate 2 bonding thus.As heat molten type bonding agent, such as rubber series heat molten type bonding agent, Polyester heat molten type bonding agent, olefin-based heat molten type bonding agent etc. can be listed.Preferably list rubber series heat molten type bonding agent.

The softening temperature (ring and ball method) of heat molten type bonding agent is such as 100 ~ 200 DEG C.In addition, the melt viscosity of heat molten type bonding agent is such as 100 ~ 30000mPas at 180 DEG C.

In addition, such as also thermal conductive particle can be contained as required in above-mentioned bonding agent.

As thermal conductive particle, such as thermally conductive inorganic particles, thermal conductivity organic granular etc. can be listed, preferably list thermally conductive inorganic particles.

As thermally conductive inorganic particles, the nitride particles such as such as boron nitride particle, aluminum nitride particle, silicon nitride particle, gallium nitride particle can be listed; The such as hydroxide particles such as aluminum hydroxide particles, magnesium hydroxide particle; The oxide particles such as such as silicon oxide particle, alumina particle, titan oxide particles, Zinc oxide particles, granules of stannic oxide, copper oxide particle, nickel oxide particle; The carbide particles such as such as silicon-carbide particle; The carbonate particles such as such as calcium carbonate granule; The metal acid-salt particles such as the such as titanate such as barium titanate particles, potassium titanate particle particle; The metallic particles etc. such as such as copper particle, Argent grain, gold grain, nickel particle, alumina particles, platinum particle.

These thermal conductive particles, may be used singly or in combination of two or more.

As the shape of thermal conductive particle, such as bulk, needle-like, sheet, stratiform, tubulose etc. can be listed.The average grain diameter (maximum length) of thermal conductive particle is such as 0.1 ~ 1000 μm.

In addition, thermal conductive particle has such as anisotropic thermal conductivity or isotropic thermal conductivity.Preferably there is isotropic thermal conductivity.

The thermal conductivity of thermal conductive particle is such as more than 1W/mK, is preferably more than 2W/mK, more preferably more than 3W/mK; Be generally below 1000W/mK.

The mixing ratio of thermal conductive particle relative to the resinous principle of 100 mass parts bonding agents, such as, is below 190 mass parts, is preferably below 900 mass parts.In addition, thermal conductive particle take volume as the mixing ratio of benchmark be 95 below volume %, be preferably 90 below volume %.

When thermal conductive particle is blended in bonding agent, thermal conductive particle is joined in bonding agent with above-mentioned mixing ratio, is uniformly mixed.

Thus, bonding agent is prepared as thermal conductivity bonding agent.

The thermal conductivity of thermal conductivity bonding agent is such as more than 0.01W/mK, is generally below 100W/mK.

As adhesive, such as, be selected from following known adhesive aptly: acrylic adhesive, silicon-type adhesive, elastomeric adhesive, vinyl alkyl ethers system adhesive, Polyester adhesive, polyamide-based adhesive, polyurethane series adhesive, Styrene-diene block copolymerization system adhesive etc.Adhesive can be used alone or two or more combinationally uses.As adhesive, preferably list acrylic adhesive, silicon-type adhesive, elastomeric adhesive; Preferably list acrylic adhesive, silicon-type adhesive further.In addition, also can contain above-mentioned thermal conductive particle using ratio similar to the above and adhesive be prepared as heat conductive adhesive in adhesive.The thermal conductivity of heat conductive adhesive as described above.

The thickness T of bonding adhesive layer 7 is such as less than 50 μm, is preferably less than 25 μm, more preferably less than 15 μm; Be generally more than 1 μm.When the thickness T of bonding adhesive layer 7 exceedes above-mentioned scope, sometimes can not make the heat that produced by electronic component 3 from thermal conductivity layer 6 through bonding adhesive layer 7 heat transfer to framework 4.

And, in order to obtain thermal conductivity adhesive sheet 5, with reference to shown in Fig. 4, first, preparing above-mentioned thermal conductivity layer 6, then, bonding adhesive layer 7 being laminated in the back side of thermal conductivity layer 6.

Specifically, it is made to dissolve by above-mentioned solvent being matched with bonding agent (be preferably heat curable adhesive) or adhesive, prepare varnish thus, described varnish is coated on membrane surface, thereafter, the organic solvent of varnish is removed by constant pressure and dry or vacuum (decompression) drying and distilling.In addition, the solid component concentration of varnish is such as 10 ~ 90 quality %.

Thereafter, bonding adhesive layer 7 is made to fit in thermal conductivity layer 6.When bonding adhesive layer 7 is fitted with thermal conductivity layer 6, carry out as required crimping or thermo-compressed.

Then, the manufacture method of Fig. 5 to heat-radiating structure 1 is used to be described.

First, in the method, as shown in Figure 5, the substrate 2 being provided with electronic component 3 is fixed on the housing (not shown) that support framework 4, and prepares thermal conductivity adhesive sheet 5.

In addition, sharp processing is carried out to thermal conductivity adhesive sheet 5, when projecting to make its through-thickness, comprise substrate 2.Specifically, thermal conductivity adhesive sheet 5 cutting processing is following size: its central portion and an end overlapping with substrate 2, another end is not overlapping with substrate 2.

Then, in the method, as shown in Figure 5, thermal conductivity adhesive sheet 5 hot pressing is connected to electronic component 3 and substrate 2 and framework 4.

Specifically, the central portion of thermal conductivity adhesive sheet 5 and an end hot pressing are connected to electronic component 3 and substrate 2, and another end hot pressing of thermal conductivity adhesive sheet 5 is connected to framework 4.

Specifically, first, as shown in dash-dot lines in fig. 5, thermal conductivity adhesive sheet 5 and substrate 2 are configured to the central portion of bonding adhesive layer 7 and an end face to electronic component 3, and make another bend at end of thermal conductivity adhesive sheet 5.

Then, shown in the arrow of reference Fig. 5, the central portion of thermal conductivity adhesive sheet 5 is contacted with substrate 2 with electronic component 3 with an end, and another end of thermal conductivity adhesive sheet 5 is contacted with framework 4, then, add heat conductivity adhesive sheet 5, the central portion of thermal conductivity adhesive sheet 5 and an end are crimped (pressing towards substrate 2 simultaneously, i.e. thermo-compressed), and another end of thermal conductivity adhesive sheet 5 is crimped (pressing, i.e. thermo-compressed) towards framework 4.

Crimping is, such as, make pressing thermal conductivity adhesive sheet 5 limit, sponge roller limit formed by resins such as organic siliconresins roll on the surface (upper surface of thermal conductivity layer 6) of thermal conductivity adhesive sheet 5.

Heating-up temperature is such as 40 ~ 120 DEG C.

In this thermo-compressed, because the flexibility of bonding adhesive layer 7 improves, with reference to shown in Fig. 1, the electronic component 3 outstanding to table side (upside) from the surface (upper surface) of substrate 2 wears out bonding adhesive layer 7, and the surface (upper surface) of electronic component 3 contacts with the back side (below) of thermal conductivity layer 6.In addition, the gap (gap such as between resistor 23 with substrate 2) 14 formed around electronic component 3 is filled by bonding adhesive layer 7.Further, bonding adhesive layer 7 be wound around cover for connect electronic component 3 (specifically, being IC chip 20 and resistor 23) and substrate 2, not shown terminal and/or go between 15.

Specifically, the upper surface of electronic component 3 and the top of side surface are covered by thermal conductivity layer 6.

On the other hand, the bottom of the side surface of electronic component 3 is covered (bonding or bonding) by the bonding adhesive layer 7 worn out by electronic component 3.

More specifically, in thermo-compressed, when resinous principle 9 is heat-curing resin composition, resinous principle 9 becomes B-stage, and therefore thermal conductivity layer 6 is bonded in the surface (upper surface) of the substrate 2 exposed from electronic component 3.Further, when the thickness of the bonding adhesive layer of Thickness Ratio 7 of electronic component 3 is thick, in thermal conductivity layer 6, the top of electronic component 3 enters into inside from the back side of thermal conductivity layer 6.

In addition, when bonding agent is heat molten type bonding agent, by above-mentioned thermo-compressed, bonding adhesive layer 7 melting or softening, the central portion of bonding adhesive layer 7 and the surface of an end and substrate 2 and the side surface thermal welding of electronic component 3, and the inner surface thermal welding of another end of bonding adhesive layer 7 and framework 4.

When bonding agent is heat curable adhesive, by above-mentioned thermo-compressed, bonding adhesive layer 7 becomes B-stage state, central portion and an end of bonding adhesive layer 7 are temporarily fixed on the upper surface of substrate 2 and the side surface of electronic component 3, and another end of bonding adhesive layer 7 is temporarily fixed on the inner surface of framework 4.

Thereafter, when resinous principle 9 is heat-curing resin composition, make thermal conductivity layer 6 hot curing, and make the hot curing of bonding adhesive layer 7 when bonding agent is heat curable adhesive.

In order to make thermal conductivity layer 6 and bonding adhesive layer 7 hot curing, such as, the framework 4 of thermal conductivity adhesive sheet 5, substrate 2 and electronic component 3 is had to drop into drying machine by temporary fixed.The condition of hot curing is: heating-up temperature is such as 100 ~ 250 DEG C, is preferably 120 ~ 200 DEG C; Heating time is such as 10 ~ 200 minutes, is preferably 60 ~ 150 minutes.

Thus, the central portion of thermal conductivity adhesive sheet 5 and an end bonding with electronic component 3 and substrate 2, and another end of thermal conductivity adhesive sheet 5 is bonding with framework 4.

Then, in above-mentioned heat-radiating structure 1, because electronic component 3 is covered by thermal conductivity adhesive sheet 5, therefore, it is possible to by the heat that produced by electronic component 3 from the upper surface of electronic component 3 and side surface heat transfer to thermal conductivity adhesive sheet 5.Then, described heat can be made from thermal conductivity adhesive sheet 5 heat transfer to framework 4, and externally dispel the heat in framework 4.

Therefore, it is possible to the heat produced by electronic component 3 is dispelled the heat effectively by thermal conductivity adhesive sheet 5 and framework 4.

In addition, by thermal conductivity adhesive sheet 5 is arranged at so simple and easy and workability of excellence on substrate 2 in the mode of overlay electronic part 3, the heat produced can be dispelled the heat by electronic component 3.

Fig. 6 illustrates the sectional view of other execution modes (form that thermal conductivity adhesive sheet is made up of thermal conductivity layer) of heat-radiating structure of the present invention; Fig. 7 is the process chart of the heat-radiating structure for construction drawing 6; Fig. 8 illustrates the sectional view of other execution modes (form of another ends contact housing of thermal conductivity adhesive sheet) of heat-radiating structure of the present invention; Fig. 9 illustrates the sectional view of other execution modes (form of bonding adhesive layer contact electronic component upper surface) of heat-radiating structure of the present invention.

In addition, in each accompanying drawing afterwards, give identical reference marks to the component corresponding with above-mentioned each portion, description is omitted.

In the above description, although thermal conductivity adhesive sheet 5 is provided with bonding adhesive layer 7, such as shown in Figure 6, also can not establish bonding adhesive layer 7, form thermal conductivity adhesive sheet 5 by thermal conductivity layer 6.

In figure 6, the side surface of electronic component 3 contacts with thermal conductivity layer 6.Specifically, contact with thermal conductivity layer 6 with whole side surface of electronic component 3 above the substrate 2 exposed from electronic component 3.

In order to obtain this heat-radiating structure 1, as shown in Figure 7, the substrate 2 being provided with electronic component 3 is fixed on the housing (not shown) of support frame 4, and prepares thermal conductivity adhesive sheet 5.Thermal conductivity adhesive sheet 5 is made up of thermal conductivity layer 6.

Then, as shown in phantom in fig. 7, thermal conductivity adhesive sheet 5 is made to bend, then, shown in the arrow of reference Fig. 7, the central portion of thermal conductivity adhesive sheet 5 and an end hot pressing are connected to electronic component 3 and substrate 2, and another end hot pressing of thermal conductivity adhesive sheet 5 is connected to framework 4.

In the thermo-compressed of thermal conductivity adhesive sheet 5, when resinous principle 9 is heat-curing resin composition, because resinous principle 9 becomes B-stage state, the gap 14 therefore formed around electronic component 3 is filled by thermal conductivity layer 6.

Thus, thermal conductivity adhesive sheet 5 is temporarily fixed on substrate 2 and framework 4.

Thereafter, when resinous principle 9 is heat-curing resin composition, make thermal conductivity layer 6 hot curing.

Thus, the upper surface of the central portion of thermal conductivity layer 6 and end and electronic component 3 and side surface and the upper surface of substrate 2 exposed from electronic component 3 bonding, and another end of thermal conductivity layer 6 is adhered to the right lateral surface of framework 4.

In this heat-radiating structure 1, thermal conductivity layer 6 directly contacts with the right lateral surface of framework 4 with the surface of electronic component 3.Therefore, the heat produced from electronic component 3, compared with the heat-radiating structure 1 of Fig. 1, can more effectively be dispelled the heat via thermal conductivity layer 6 by the heat-radiating structure 1 of Fig. 6.

On the other hand, in the heat-radiating structure 1 of Fig. 1, thermal conductivity layer 6 is bonding with substrate 2 and framework 4 by bonding adhesive layer 7, and therefore, compared with the heat-radiating structure 1 of Fig. 6, thermal conductivity adhesive sheet 5 is bonding more reliably, long-term performance can go out more excellent thermal diffusivity.

In addition, in the explanation of above-mentioned Fig. 1 and Fig. 6, although as the thermal diffusivity component in the present invention exemplified with framework 4, but thermal diffusivity component is not limited thereto, such as, also can exemplify housing 10 (Fig. 8), heat abstractor (not shown), reinforcement bundle (not shown) etc.

In fig. 8, what housing 10 opened on the upside of making has under casing shape, the sidewall 11 integrally possessing diapire 13 and extend upward from its peripheral end portion.Sidewall 11 is configured in substrate 2 around, and diapire 13 is configured in the downside of substrate 2.Housing 10 is formed by metals such as such as aluminium, stainless steel, copper, iron.

In addition, the other end part from central portion of thermal conductivity adhesive sheet 5 bends downwards from an end margin of substrate 2; Another end being configured to thermal conductivity adhesive sheet 5 extends downwards in the right lateral surface (inner surface) of framework 4.The bottom of another end of thermal conductivity adhesive sheet 5 and the right lateral surface of framework 4 (being specially the vicinity of sidewall 11 and the connecting portion of diapire 13) contacts.

In addition, in the above description, although bonding adhesive layer 7 to be layered in the one side (back side) of thermal conductivity layer 6, such as also as shown in the dotted line of the dotted line of Fig. 1 and Fig. 4, the two sides (surface and the back side) of thermal conductivity adhesive sheet 5 can be formed at.

In addition, in the explanation of above-mentioned Fig. 1, implement thermo-compressed and bonding adhesive layer 7 is worn out by electronic component 3, but such as also can implement with reference to shown in Fig. 9, bonding adhesive layer 7 is not worn out by electronic component 3, but is covered in the upper surface of electronic component 3.

Bonding adhesive layer 7 can be configured to and contacts with the upper surface of electronic component 3 on the one hand, does not contact on the other hand, configure with the upper surface of substrate 2 across certain intervals (gap) with the upper surface of the substrate 2 exposed from electronic component 3.

This heat-radiating structure 1 also can by the heat from electronic component 3 via bonding adhesive layer 7 heat transfer to thermal conductivity layer 6, further, this thermal conductivity layer 6 can by described heat to thermal diffusivity component 4 heat conveying.

embodiment

Preparation example, embodiment and production example are below shown, more specific description is carried out to the present invention, but the present invention is not by any restriction of embodiment.

the preparation of thermal conductivity layer

preparation example 1

Coordinate 13.42g PT-110 (trade name, the boron nitride particle of sheet, average grain diameter (light scattering method) 45 μm, Momentive Performance Materials Japan.LLC manufactures), 1.0g JER828 (trade name, bisphenol A type epoxy resin, 1st epoxy resin, liquid, epoxide equivalent 184 ~ 194g/eqiv., softening temperature (ring and ball method) is less than 25 DEG C, melt viscosity (80 DEG C) 70mPas, Japan Epoxy Resins Co., Ltd. manufacture), with 2.0g EPPN-501HY (trade name, triphenylmethane type epoxy resin, 2nd epoxy resin, solid-state, epoxide equivalent 163 ~ 175g/eqiv., softening temperature (ring and ball method) 57 ~ 63 DEG C, chemical drug Inc. of Japan makes) and 3g (solid constituent 0.15g) curing agent (Curezol 2P4MHZ-PW (trade name, four countries change into company and manufacture) 5 quality % methylethylketone dispersion liquids) (be 5 quality %s relative to the total amount of epoxy resin and JER828 and EPPN-501HY) stir, placed for 1 evening under room temperature (23 DEG C), methylethylketone (dispersant of curing agent) is volatilized, prepare semi-solid mixture.

In addition, in above-mentioned cooperation, relative to the cumulative volume of the solid constituent (that is, the solid constituent of boron nitride particle and epoxy resin) of deduction curing agent, the percentage by volume (volume %) of boron nitride particle is 70 volume %.

Then, gained mixture is clamped with 2 mould release films of organosilicon process, used vacuum hotpressing machine 80 DEG C, under the atmosphere (vacuum atmosphere) of 10Pa, carry out hot pressing in 2 minutes with the load of 5 tons (20MPa), obtain the compacting sheet material ((a) with reference to Fig. 2) that thickness is 0.3mm thus.

Thereafter, gained compacting sheet material is cut to be divided into multiple modes when projecting along the thickness direction of compacting sheet material, obtain thus splitting sheet material ((b) with reference to Fig. 2), then, laminated sheet ((c) with reference to Fig. 2) is obtained at the stacked segmentation sheet material of thickness direction.

Then, resultant layer stacks of sheets heating in vacuum press similar to the above is carried out hot pressing ((a) with reference to Fig. 2) under condition similar to the above.

Then, by the sequence of operations (with reference to Fig. 2) of above-mentioned cutting, stacked and hot pressing, repeat 4 times and obtain the thermal conductivity layer (its uncured state, reference Fig. 3) that thickness is 0.3mm.

preparation example 2 ~ 16

According to mixing ratio and the manufacturing condition of table 1 ~ table 3, carry out the process same with preparation example 1 and obtain thermal conductivity layer (preparation example 2 ~ 16, with reference to Fig. 3).

the making of thermal conductivity adhesive sheet

production example 1

The varnish (solvent: MEK, solid component concentration: 50 quality %, no-arbitrary pricing type) of acrylic adhesive is coated membrane surface, makes thickness during drying be 10 μm.Then, by vacuumize, distillation removing MEK, forms adhesive phase thus.

Then, make the adhesive phase of preparation example 1 be crimped on thermal conductivity layer, thus, make thermal conductivity adhesive sheet (with reference to Fig. 4).

production example 2 ~ 16

Except the thermal conductivity layer using preparation example 2 ~ 16 respectively, carry out same process with production example 1, obtain thermal conductivity adhesive sheet (production example 2 ~ 16) (with reference to Fig. 4) respectively.

the making of heat-radiating structure

embodiment 1

Prepare the flat-shaped substrate formed by polyimides, the electronic component (resistor of the IC chip of thickness 2mm, the electric capacity of 1mm, the coil of 4mm and 0.5mm) that it is installed, framework (reference Fig. 5).

Then, the thermal conductivity adhesive sheet of production example 1 is cut into central portion and a size that end is overlapping with substrate, another end is not overlapping with substrate.

Then, thermal conductivity adhesive sheet and substrate are configured to the central portion of adhesive phase and an end face to electronic component, then, another end of thermal conductivity adhesive sheet is bent upward, thereafter, use the sponge roller formed by organic siliconresin, by thermal conductivity adhesive sheet towards electronic component and framework crimping (temporary fixed) (with reference to Fig. 9).

Thus, the central portion of thermal conductivity adhesive sheet and end are adhered to the upper surface of electronic component, and another end of thermal conductivity adhesive sheet is adhered to framework.

In addition, at the central portion of thermal conductivity adhesive sheet with form gap (with reference to Fig. 9) between an end and the substrate exposed from electronic component.

embodiment 2 ~ 16

Except the thermal conductivity adhesive sheet of the production example 2 ~ 16 recorded in use table 4 respectively replaces except the thermal conductivity adhesive sheet of production example 1, form heat-radiating structure (embodiment 2 ~ 16) similarly to Example 1 respectively.

embodiment 17

Except not arranging except adhesive phase in the making of thermal conductivity adhesive sheet, make heat-radiating structure (with reference to Fig. 6) similarly to Example 1.

embodiment 18 ~ 32

Except not arranging except adhesive phase in the making of thermal conductivity adhesive sheet, make heat-radiating structure (embodiment 18 ~ 32) (with reference to Fig. 6) respectively in the same manner as embodiment 2 ~ 16.

evaluate

1. thermal conductivity

Thermal conductivity is measured to the thermal conductivity layer of preparation example 1 ~ 16.

That is, xenon flash lamp analyzer " LFA-447 type " (manufacture of NETZS CH company) is used to measure the thermal conductivity in direction, face (SD) according to PULSE HEATING method.

Its result is illustrated in table 1 ~ table 3.

2. porosity (P)

Measure the porosity (P1) of the thermal conductivity layer before the hot curing of preparation example 1 ~ 16 by the following method.

The assay method of porosity: first, by Cross section polishing instrument (CP), carries out cutting processing by heat conductive sheet through-thickness, observes under 200 times the cross section scanning electron microscopy (SEM) occurred thus, obtains image.After this, by gained image, binary conversion treatment is carried out to aperture sections and the part beyond it, then calculate the area ratio of the aperture sections sectional area overall relative to heat conductive sheet.

Its result is illustrated in table 1 ~ table 3.

3. difference in height tracing ability (three point bending test)

To the thermal conductivity layer before the hot curing of preparation example 1 ~ 16, under following experimental condition, implement three point bending test according to JIS K7171 (2008), evaluate difference in height tracing ability according to following metewand thus.Its result is illustrated in table 1 ~ table 3.

Experimental condition

Test film: size 20mm × 15mm

Distance between the fulcrum: 5mm

Test speed: 20mm/min (the pressing down speed of pressure head)

Angle of bend: 120 degree

metewand

◎: do not observe fracture completely.

Zero: almost do not observe fracture.

×: clearly observe fracture.

4. typographic(al) mark identity (typographic(al) mark tack: by ink jet printing or the mark tack of laser printing)

By ink jet printing and laser printing, typographic(al) mark on the thermal conductivity layer of preparation example 1 ~ 16, observes described mark.

Its result, the thermal conductivity layer of preparation example 1 ~ 16 any one in, all can recognize the mark based on ink jet printing and laser printing well, confirm that typographic(al) mark tack is good.

5. volume resistance

Measure the volume resistance (R) of the thermal conductivity layer of preparation example 1 ~ 16.

That is, the volume resistance (R) of thermal conductivity layer is measured according to JIS K 6911 (the ordinary test method of Thermocurable plastics, version in 2006).

Its result is illustrated in table 1 ~ table 3.

6. initial bonding force test

6-1. is to the initial bonding force test of notebook installation base plate

For the uncured thermal conductivity layer of preparation example 1 ~ 16, initial bonding force test (1) and (2) is implemented to the notebook installation base plate being provided with multiple electronic component.

Namely, use the sponge roller formed by organic siliconresin, under 80 DEG C (preparation example 1 ~ 9 and preparation examples 11 ~ 16) or 120 DEG C (preparation example 10), the heating of thermal conductivity layer be crimped on the surface of notebook computer installation base plate in the horizontal direction and carry out temporary fixed, place after 10 minutes, then notebook installation base plate is arranged to along the vertical direction (initial bonding force test (2)).

Then, notebook computer installation base plate is arranged to thermal conductivity layer and points to downside (that is, making it reverse up and down from just temporary fixed state) (initial bonding force test (1)).

Then, in above-mentioned initial bonding force test (1) and initial bonding force test (2), according to following standard, thermal conductivity layer is evaluated.Its result is illustrated in table 1 ~ table 3.

standard

Zero: confirm that thermal conductivity layer does not come off from notebook computer installation base plate.

×: confirm that thermal conductivity layer comes off from notebook computer installation base plate.

6-2. is to the initial bonding force test of stainless steel substrate

For the uncured thermal conductivity layer of preparation example 1 ~ 16, implement initial bonding force test (1) and (2) relative to stainless steel substrate (SUS304 system) as described above.

standard

Zero: confirm that thermal conductivity layer does not come off from stainless steel substrate.

×: confirm that thermal conductivity layer comes off from stainless steel substrate.

7. volume resistance

Measure the volume resistance (R) of the uncured thermal conductivity layer of preparation example 1 ~ 16.

Its result is illustrated in table 1 ~ table 3.

8. thermal diffusivity

Make the electronic component work in the heat-radiating structure of embodiment 1 ~ 32, through 1 hour.By the surface temperature of thermal conductivity adhesive sheet in the work of infrared camera mensuration, result is 70 DEG C, confirms temperature and rises suppressed.

On the other hand, to the substrate (substrate in the heat-radiating structure of comparative example 1) not using thermal conductivity adhesive sheet, carry out same evaluation, the temperature of electronic component vertical direction is 130 DEG C.

Accordingly, the thermal diffusivity confirming the heat-radiating structure of embodiment 1 ~ 32 is excellent.

Table 1

G ^{* A}: fit quality

[volume %] ^{* B}: relative to the percentage of the cumulative volume of thermally-conductive sheet (deduction curing agent)

[volume %] ^{* C}: relative to the percentage of the cumulative volume of thermally-conductive sheet

Number of times] ^{* D}: the number of times of the hot pressing of laminated sheet

Table 2

G ^{* A}: fit quality

Number of times ^{* D}: the number of times of the hot pressing of laminated sheet

Table 3

G ^{* A}: fit quality

table 4

Numerical value in each composition in table 1 ~ table 3 represents grams when not having special record.

In addition, in the hurdle of the boron nitride particle of table 1 ~ table 3, numerical value is above the fit quality (g) of boron nitride particle, middle numerical value is relative to deducting the solid constituent of curing agent (namely in heat conductive sheet, boron nitride particle, with epoxy resin or poly solid constituent) cumulative volume, the percentage by volume (volume %) of boron nitride particle, numerical value be below relative to heat conductive sheet solid constituent (namely, boron nitride particle, with the solid constituent of epoxy resin or curing agent) cumulative volume, the percentage by volume (volume %) of boron nitride particle.

In addition, each composition of his-and-hers watches 1 ~ table 3, with the composition of ※, below records its detailed content.

PT-100 ^{※ 1}: the boron nitride particle of trade name, sheet, average grain diameter (light scattering method) 45 μm, Momentive Performance Materials Japan LLC manufacture

UHP-1 ^{※ 2}: trade name: SHOBN UHP-1, the boron nitride particle of sheet, average grain diameter (light scattering method) 9 μm, Showa electrician manufactures

Epoxy resin A ^{※ 3}: OGSOL EG (trade name), two aryl fluorenes type epoxy resin, semisolid, epoxide equivalent 294g/eqiv., softening temperature (ring and ball method) 47 DEG C, melt viscosity (80 DEG C) 1360mPas, Osaka Gas Chemicals Co., Ltd. manufactures

Epoxy resin B ^{※ 4}: JER828 (trade name), bisphenol A type epoxy resin, liquid, epoxide equivalent 184 ~ 194/eqiv., softening temperature (ring and ball method) is less than 25 DEG C, melt viscosity (80 DEG C) 70mPas, Japan Epoxy Resins Co., Ltd. manufactures

Epoxy resin C ^{※ 5}: JER1002 (trade name), bisphenol A type epoxy resin, solid-state, epoxide equivalent 600 ~ 700g/eqiv., softening temperature (ring and ball method) 78 DEG C, melt viscosity (80 DEG C) more than 10000mPas (measuring more than boundary), Japan EpoxyResins Co., Ltd. manufactures

Epoxy resin D ^{※ 6}: EPPN-501HY (trade name), triphenylmenthane type epoxy resin, solid-state, epoxide equivalent 163 ~ 175/eqiv., softening temperature (ring and ball method) 57 ~ 63 DEG C, Japanese chemical drug Inc. makes

Curing agent ^{※ 7}: the 5 quality % methyl ethyl ketone solutions of Curezol 2PZ (trade name, four countries change into company and manufacture)

Curing agent ^{※ 8}: the 5 quality % methylethylketone dispersion liquids of Curezol 2P4MHZ-PW (trade name, four countries change into company and manufacture)

Polyethylene ^{※ 9}: low density polyethylene (LDPE), weight average molecular weight (Mw) 4000, number-average molecular weight (Mn) 1700, Aldrich company manufactures

In addition, above-mentioned explanation provides as illustrative execution mode of the present invention, but this only simple illustration, can not as limited explanation.Obvious variation of the present invention, is also contained in the right of patent to those skilled in the art.

Claims

1. a heat-radiating structure, is characterized in that,

It possesses substrate, be installed on the electronic component of described substrate, for thermal diffusivity component that the heat produced by described electronic component is carried out dispelling the heat and the thermal conductivity adhesive sheet be arranged in the mode covering described electronic component on described substrate,

Described thermal conductivity adhesive sheet possesses the thermal conductivity layer of boron nitride particle containing sheet and resinous principle,

The thermal conductivity in the direction orthogonal with described thermal conductivity layer thickness direction of described thermal conductivity layer is more than 4W/mK,

The porosity of described thermal conductivity layer is 30 below volume %,

Described thermal conductivity layer and described thermal diffusivity member contact,

Described thermal conductivity layer is prepared by following operation:

The operation that hot pressing suppresses sheet material is carried out to being mixed with the mixture obtained by described boron nitride particle and described resinous principle,

Described compacting sheet material is divided into the segmentation process of multiple segmentation sheet material,

Described multiple cutting plate sheet material layers is folded the lamination process of standby laminated sheet, and

Described laminated sheet is carried out to the hot pressing process of hot pressing.

2. heat-radiating structure according to claim 1, is characterized in that,

Described thermal conductivity adhesive sheet has bond layer or the adhesive phase of at least one side being layered in described thermal conductivity layer,

Described bond layer or described adhesive phase and described substrate bonding or bonding.

3. heat-radiating structure according to claim 1, is characterized in that,

Described porosity is 10 below volume %.

4. heat-radiating structure according to claim 1, is characterized in that,

Described boron nitride particle is dispersed in described resinous principle.

5. the heat-radiating structure according to any one of claim 1-4, is characterized in that,

Described thermal conductivity layer is by repeatedly implementing the series of processes preparation of segmentation process, lamination process and hot pressing process, and the number of occurrence of these operations is 2 ~ 7 times.