Summary of the invention
Main purpose of the present invention provides a kind of Intelligent Power Module and preparation method thereof, is intended to improve the anti-noise ability and the heat dispersion that improve simultaneously Intelligent Power Module.
The present invention proposes a kind of Intelligent Power Module, comprise an aluminium base, this aluminium base upper surface is provided with insulating barrier on, insulating barrier is provided with a wiring layer on this, this wiring layer is provided with some circuit elements and pin, described aluminium base lower surface is provided with insulating barrier, this time insulating barrier is provided with a heating panel, described aluminium base, upper insulating barrier, the wiring layer, some circuit elements and pin, and insulating barrier is encapsulated in the sealing resin down, and wherein, described pin runs through described sealing resin and stretches out, the side of described heating panel is encapsulated by described sealing resin, and the lower surface of described heating panel is exposed.
Preferably, described upper insulating barrier adopts and fill Al in epoxide resin material
2O
3And make, the thermal conductivity of described upper insulating barrier is 2.0W/mk.
Preferably, described lower insulating barrier adopts filling BN in epoxide resin material and makes, and the thermal conductivity of described lower insulating barrier is 5.0W/mk.
Preferably, described Intelligent Power Module also comprises some at described circuit element, wiring layer, and sets up the metal wire that is electrically connected between the aluminium base.
Preferably, described upper insulating barrier is provided with at least one for setting up the hole of exposing that is electrically connected for described aluminium base with wiring layer or circuit element.
The present invention further also proposes a kind of manufacture method of Intelligent Power Module, comprising:
Form insulating barrier and lower insulating barrier in the upper and lower surface of aluminium base respectively;
Insulating barrier forms the wiring layer on described, and at described wiring layer some circuit elements and pin is installed;
At described lower insulating barrier heating panel is set;
Encapsulate described aluminium base, upper insulating barrier, wiring layer, some circuit elements and pin, and lower insulating barrier.
Preferably, encapsulate described aluminium base, upper insulating barrier, wiring layer, some circuit elements and pin by transfer die or the mode of injecting mould, and lower insulating barrier.
Preferably, described upper and lower surface at aluminium base also comprises before forming respectively the step of insulating barrier and lower insulating barrier:
The upper and lower surface of described aluminium base is carried out corrosion protection to be processed.
Preferably, the described step that insulating barrier forms the wiring layer on described specifically comprises:
Copper foil on the insulating barrier on described;
The described Copper Foil of etching forms described wiring layer.
Preferably, comprise before the described step that some circuit elements and pin be installed at described wiring layer:
The described aluminium base of preheating and wiring layer.
Intelligent Power Module of the present invention can reliably realize the insulation in metal aluminum substrate and the external world by lower insulator separation, and the heating panel of setting up can improve the heat dispersion of Intelligent Power Module.Because the thermal conductivity far of lower insulating barrier and heating panel is higher than sealing resin, therefore when Intelligent Power Module works the temperature of internal components far below existing product, make Intelligent Power Module have simultaneously higher anti-noise ability and heat dispersion, significantly improved job stability and the useful life of Intelligent Power Module.
Embodiment
Be described further with regard to technical scheme of the present invention below in conjunction with drawings and the specific embodiments.Should be appreciated that specific embodiment described herein only in order to explain the present invention, is not intended to limit the present invention.
The present invention proposes a kind of Intelligent Power Module.
With reference to Fig. 2, Fig. 2 is the cross-sectional view of Intelligent Power Module of the present invention
In one embodiment of this invention, this Intelligent Power Module comprises an aluminium base 10, the upper and lower surface of this aluminium base 10 arranges respectively on one insulating barrier 20 and insulating barrier 60 once, upward the upper surface of insulating barrier 20 is provided with a wiring layer 30, this wiring layer 30 is provided with some circuit elements 40 and pin 50, and the lower surface of lower insulating barrier 60 is provided with a heating panel 70.This aluminium base 10, upper insulating barrier 20, wiring layer 30, some circuit elements 40, pin 50 and lower insulating barrier 60 are encapsulated in the sealing resin 80, wherein pin 50 runs through sealing resin 80 and stretches out, sealed resin 80 encapsulation in the side of heating panel 70, the lower surface of heating panel 70 is exposed to be contacted with outside air.
The rectangular plate of the aluminium alloys such as aluminium base 10 preferred employings 1100 or 5052 is made.Wiring layer 30 and heating panel 70 preferably are made of copper.The thickness of heating panel 70 is identical with the thickness of wiring layer 30.
Comprise some pads 31 on the wiring layer 30, this pad 31 is arranged on one side of aluminium base 10, and is a plurality of alignings arrangements, and pin 50 and pad 31 welding are used for the various signals of I/O.Pin 50 preferred employing aluminium etc. have the metal of certain degree of hardness to be made, and can utilize the hardness of pin 50 when molded aluminium base 10 to be fixed.
Circuit element 40 is fixed on the allocated circuit that consists of on the wiring layer 30, circuit element 40 adopts active element or the passive components such as electric capacity or resistance such as transistors or diode, also can be fixed on the aluminium base 10 by the radiator circuit element 40 that the caloric values such as power component is large of being made by copper etc.
Sealing resin 80 can use thermosetting resin molded by the transfer die mode, also can use injection mould mode to use thermoplastic resin molded.
Intelligent Power Module of the present invention can reliably realize the insulation in metal aluminum substrate 10 and the external world by lower insulating barrier 60 isolation, and the heating panel 70 of setting up can improve the heat dispersion of Intelligent Power Module.Because the thermal conductivity far of lower insulating barrier 60 and heating panel 70 is higher than sealing resin 80, therefore when Intelligent Power Module works the temperature of internal components far below existing product, make Intelligent Power Module have simultaneously higher anti-noise ability and heat dispersion, significantly improved job stability and the useful life of Intelligent Power Module.
In the above-described embodiments, upper insulating barrier 20 adopts at resin material middle and high concentrations such as epoxy resin and fills Al
2O
3And make, owing to filled Al
2O
3Can effectively improve the thermal conductivity of upper insulating barrier 20, further improve the heat-sinking capability of Intelligent Power Module.The thermal conductivity of upper insulating barrier 20 is preferably 2.0W/mk, is complementary with the coefficient of expansion and the sealing resin 80 that guarantees upper insulating barrier 20, has prevented that upper insulating barrier 20 from coming off because being heated.
In the above-described embodiments, lower insulating barrier 60 adopts at resin material middle and high concentrations such as epoxy resin and fills BN and make, owing to filled the thermal conductivity that BN can effectively improve lower insulating barrier 60, has further improved the heat-sinking capability of Intelligent Power Module.The thermal conductivity of lower insulating barrier 60 is preferably 5.0W/mk, is complementary with the coefficient of expansion and the sealing resin 80 that guarantees lower insulating barrier 60, has prevented that time insulating barrier 60 from coming off because being heated.
In the above-described embodiments, Intelligent Power Module also comprises some at some circuit elements 10, wiring layer 30, and sets up the metal wire 90 that is electrically connected between the aluminium base 10.This metal wire 90 is preferably aluminum steel, gold thread or copper cash.
In the above-described embodiments, upper insulating barrier 20 is provided with at least one hole 21 of exposing, and this exposes hole 21 and is used for passing for metal wire 90, to be electrically connected wiring layer 30 and aluminium base 10 or circuit element 40.This exposes hole 21 and is arranged on the position close with the earth potential of wiring layer 30, and its degree of depth need run through insulating barrier 20 exposes aluminium base 10.This exposes the 0.5mm place that hole 21 preferably is arranged on the earth potential edge of wiring layer 30.
The present invention further also proposes a kind of manufacture method of Intelligent Power Module.
With reference to Fig. 3, Fig. 3 is the schematic flow sheet of the manufacture method of Intelligent Power Module of the present invention.
In one embodiment of this invention, the manufacture method of Intelligent Power Module comprises:
Step S10 forms insulating barrier and lower insulating barrier in the upper and lower surface of aluminium base respectively;
Circuit layout is as required prepared sizeable aluminium base, the preferred aluminium base that adopts 64mm * 30mm, the surface arranges insulating barrier thereon, and at least one hole of exposing of upper insulating barrier Drilling, this formation of exposing the hole can transfer to form by the smooth milling cutter high-speed rotary of front end.Because this exposes the hole and is used for aluminium base is connected with earth potential, so exposing the position in hole should approach with the earth potential of wiring layer, but can not be excessively near, otherwise be damaged to easily the wiring layer during boring, the beeline that preferably will expose the earth potential edge of bore edges and wiring layer is controlled at 0.5mm.This degree of depth of exposing the hole is just to run through upper insulating barrier as good, if too dark, tying up head in the time of may causing wiring can't test.Because upper insulating barrier is comparatively firm, so the wearing and tearing of milling cutter are very fast.And it is more remarkable to expose the less cutter wear of bore dia.Therefore when batch production, preferably use the thicker milling cutter of diameter, to reduce production costs.In addition, take into account the miniaturization of aluminium base, the diameter of milling cutter should not be too thick, to reduce to expose the area in hole.So preferably adopting diameter is that the milling cutter of Φ 1.5mm forms and to expose the hole.Both can reduce to expose the occupied area in hole, can significantly reduce again the wearing and tearing of milling cutter, thereby improve productivity.By methods such as application, pressings, the lower insulating barrier that will be in softening attitude is formed at the lower surface of aluminium base, because softening attitude lower has certain flowability, lower surface at aluminium base evenly distributes easily, but its flowability should not be excessively strong, otherwise is difficult to moulding, the lepidiod BN filler of preferred employing, make it be at normal temperatures semi-cured state, pine for entering molten state in follow-up adding, form cure states after the cooling.This moment, the size of formed lower insulating barrier should be slightly larger than heating panel, but slightly less than aluminium base.
Step S20 forms the wiring layer at upper insulating barrier;
Upper surface at upper insulating barrier is pasted with as the wiring layer.This wiring preferably is made of copper.
Step S30 installs some circuit elements and pin at the wiring layer;
At first, by scolders such as scolding tin circuit element and pin are installed in the assigned position of wiring layer.Secondly, the mode by pressure welding links together pin and wiring layer.The welding temperature of pressure-welding head is preferably 300 ℃, guarantees that tin cream fully melts, and the pressure welding time should not surpass 5 seconds, guarantees that aluminium base is to be locally heated.At last, utilize metal wire to carry out circuit element and be connected wiring with the wiring layer and connect, utilize metal wire that aluminium base is connected with earthy wiring, this metal wire is preferably aluminum steel, gold thread or copper cash.
Step S40 arranges heating panel at lower insulating barrier;
At lower insulating barrier heating panel is set, or under heating panel forms insulating barrier, its effect is identical, does not repeat them here.
Step S50, encapsulation aluminium base, upper insulating barrier, wiring layer, some circuit elements and pin, and lower insulating barrier.
At first, in oxygen-free environment aluminium base is toasted, stoving time should be less than 2 hours, and baking temperature is preferably 125 ℃, to remove the aqueous vapor of aluminium base and electric component surface attachment; Under the oxygen-free environment condition, heat, to prevent aluminium base and electric component surface oxidation.Secondly, the integral body that aluminium base, upper insulating barrier, wiring layer, some circuit elements, pin, lower insulating barrier and heating panel are formed is as in the mould, and positions.At last, annotate and water sealing resin, encapsulation is finally finished in cooling.After finishing, encapsulation according to the needs that use length pin is cut off moulding.
Above-mentioned steps S40 can finish before or after any step between step S10 and the step S50, is preferably to carry out simultaneously with step S10 or finish after step S10.
The manufacture method of Intelligent Power Module of the present invention is by adopting the lower insulating barrier that is in softening attitude before encapsulation, its flowability can guarantee the uniformity between aluminium base and heating panel, again because the thermal conductivity far of lower insulating barrier is higher than sealing resin, so to the not very strict requirement of its THICKNESS CONTROL, significantly reduced the technology difficulty of molding equipment, and need not to use the patrix thimble, the special constructions such as counterdie clamping device, when molded also not to wiring, the positions such as circuit element claim, reduce manufacturing cost and the design cost of Intelligent Power Module, improved the rate of finished products of Intelligent Power Module.
In the above-described embodiments, encapsulate aluminium base, upper insulating barrier, wiring layer, some circuit elements and pin by transfer die or the mode of injecting mould, and lower insulating barrier.
Fig. 4 is the schematic flow sheet that forms the wiring layer in the manufacture method of Intelligent Power Module of the present invention;
In the above-described embodiments, step S20 specifically comprises:
Step S21, copper foil on upper insulating barrier;
Upper surface copper foil at upper insulating barrier.
Step S22, the etching Copper Foil forms the wiring layer.
According to circuit layout etching Copper Foil, remove partly etched Copper Foil, form the wiring layer.
With reference to Fig. 5, Fig. 5 is the schematic flow sheet of another embodiment of manufacture method of Intelligent Power Module of the present invention.
Based on above-described embodiment, before step S10, also comprise:
Step S60 carries out corrosion protection to the upper and lower surface of aluminium base and processes.
Respectively the upper and lower surface of aluminium base is carried out corrosion protection and process, prevent that aluminium base is corroded, to improve the useful life of aluminium base.
Fig. 6 is the schematic flow sheet of the another embodiment of manufacture method of Intelligent Power Module of the present invention.
In the above-described embodiments, before step S30, also comprise:
Step S70, preheating aluminium base and wiring layer.
At first, aluminium base and wiring layer are placed on the plane of a heating and carry out preheating, heating plane temperature can not be too low, otherwise do not have the effect of preheating, can not be too high, otherwise the tin that has welded is melted, be preferably 100 ℃.Then, the part that pin is prepared to contact with the wiring layer is stained with tin cream, in order to improve welding quality, sometimes also can be stained with scaling powder, and be placed on the appropriate location.
The above only is the preferred embodiments of the present invention; be not so limit claim of the present invention; every equivalent structure transformation that utilizes specification of the present invention and accompanying drawing content to do; or directly or indirectly be used in other relevant technical fields, all in like manner be included in the scope of patent protection of the present invention.