Double-sided heat dissipation silicon carbide power module based on high heat conduction cushion block

Abstract

The utility model belongs to the technical field of semiconductor packaging, and particularly discloses a double-sided heat dissipation silicon carbide power module based on a high heat conduction cushion block, which comprises a metalized ceramic substrate composed of a ceramic insulating layer and metalized conductive layers on the upper surface and the lower surface of the ceramic insulating layer. Heat generated when the silicon carbide chipset works is transmitted to the upper radiator through the upper high-heat-conduction cushion block and transmitted to the lower radiator through the metalized ceramic substrate and the lower high-heat-conduction cushion block, a double-face heat dissipation path is formed, direct contact heat transfer of the high-heat-conduction upper high-heat-conduction cushion block and the lower high-heat-conduction cushion block is combined, heat resistance is reduced, heat dissipation is uniform, and heat dissipation efficiency is improved. The heat dissipation effect is good, heat is dissipated through convection between the surfaces of the heat dissipation fins and air, the heat dissipation effect is improved, the ceramic insulation layer is made of aluminum nitride, the heat conductivity and strength are high, the service life is long, the metalized conductive layer is made of metal copper, the conductive effect is good, the upper high-heat-conductivity cushion block directly makes contact with the surface of the silicon carbide chip set, extra heat resistance of a traditional welding layer is avoided, and the service life is prolonged. And the heat dissipation effect is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of semiconductor packaging, and specifically discloses a double-sided heat dissipation silicon carbide power module based on high-thermal-conductivity cushion blocks. BACKGROUND

[0002] A power module is a kind of module formed by packaging and integrating a series of power semiconductor chips in a certain topology for the purpose of realizing certain functions. Compared with a topology composed of discrete power chips, the power module has high integration, and has great advantages in electrical performance, thermal performance, safety, chip life, cost and the like.

[0003] With the continuous development of semiconductor power chips, the application environment requirements of important fields such as new energy grid connection, high-voltage direct current transmission, electric vehicles, high-speed rail, aerospace, pulse power and the like are continuously improved, and the influence of energy saving. The power module is continuously developing towards miniaturization, low loss, high power density, high reliability and high integration. In particular, the emergence of a new generation of wide-bandgap semiconductor chips represented by silicon carbide and gallium nitride materials gradually replaces silicon-based chips in various industrial fields, accelerating the development of power modules, so that the power module using wide-bandgap power semiconductor chips has smaller size, can work at higher temperature, and works at higher switching frequency, thereby further reducing the size of passive chips and improving the efficiency of the converter. Among them, the power chip represented by silicon carbide MOSFET is expected to replace traditional silicon IGBT in medium and high power working conditions

[0004] Silicon carbide power modules are widely used in new energy, electric vehicles and other fields due to their high temperature, high frequency and high efficiency characteristics. Traditional SiC modules mostly adopt single-sided heat dissipation structure (such as bottom substrate welding heat sink), but are limited by the high power density of chips, have large thermal resistance and uneven temperature distribution, which easily leads to local overheating, affecting performance and service life.

[0005] In the prior art, although double-sided heat dissipation design is attempted, the following problems exist:

[0006] The thermal expansion coefficient (CTE) of the heat-conducting material does not match the chip, generating thermal stress;

[0007] The heat dissipation path is single, and it is difficult to achieve uniform heat dissipation;

[0008] The traditional heat-conducting gasket has low thermal conductivity, and it is difficult to meet the high heat conduction requirement. SUMMARY

[0009] The utility model provides a double -sided heat dissipation silicon carbide power module based on high thermal conductivity pad, double -sided heat dissipation path, the direct contact heat transfer of the upper high thermal conductivity pad and the lower high thermal conductivity pad of high thermal conductivity is combined, and heat resistance reduces, and heat dissipation is even, and the heat dissipation effect is good.

[0010] The utility model discloses a double -sided heat dissipation silicon carbide power module based on high thermal conductivity pad, including:

[0011] The metalized ceramic substrate is composed of a ceramic insulating layer and a metalized conductive layer on the upper and lower surfaces thereof;

[0012] The silicon carbide chip set is welded to the upper surface of the metalized ceramic substrate;

[0013] The upper heat dissipation unit covers the upper surface of the silicon carbide chip set and includes an upper high thermal conductivity pad and an upper heat sink.

[0014] The lower heat dissipation unit is located below the metalized ceramic substrate and includes a lower high thermal conductivity pad and a lower heat sink.

[0015] The packaging shell covers the outer wall of the metalized ceramic substrate, the silicon carbide chip set, the upper heat dissipation unit and the lower heat dissipation unit.

[0016] Preferably, the material of the upper high thermal conductivity pad and the lower high thermal conductivity pad is one of graphene, copper composite material and elastic heat-conducting silica gel, and the surface is covered with an insulating layer.

[0017] Preferably, the outer wall of the upper heat sink and the lower heat sink is fixedly connected with a plurality of evenly distributed heat dissipation fins.

[0018] Preferably, the ceramic insulating layer is made of aluminum nitride material and has a thickness of 0.3-1 mm.

[0019] As a kind of based on high thermal conductivity pad's double-sided radiating silicon carbide power module preferred of the utility model, the packaging shell is epoxy resin material, wall thickness is 2~5mm, the outer side wall of packaging shell is provided with multiple conductive terminals, the electrode of the conductive terminal and metallized ceramic substrate is welded by ultrasonic.

[0020] As a kind of based on high thermal conductivity pad's double-sided radiating silicon carbide power module preferred of the utility model, the electrode of the conductive terminal and metallized ceramic substrate is welded by ultrasonic.

[0021] The utility model has the advantages of:

[0022] The heat generated by silicon carbide chip group when working is transferred to the upper radiator through the upper high thermal conductivity pad, and is transferred to the lower radiator through the metallized ceramic substrate and the lower high thermal conductivity pad, forming a double-sided radiating path, combining the direct contact heat transfer of the upper high thermal conductivity pad and the lower high thermal conductivity pad with high thermal conductivity, reducing the thermal resistance, evenly radiating, good radiating effect, heat is dissipated through the surface of the radiating fin and air convection, improving the radiating effect, the ceramic insulation layer is made of aluminum nitride material, with high thermal conductivity and strength, long service life, the metalized conductive layer is made of copper, with good conductivity, the upper high thermal conductivity pad directly contacts the surface of the silicon carbide chip group, avoiding the additional thermal resistance of the traditional welding layer, improving the radiating effect. BRIEF DESCRIPTION OF DRAWINGS

[0023] In order to more clearly illustrate the specific embodiment of the utility model or the technical scheme in the prior art, the following will briefly introduce the drawings needed to be used in the specific embodiment or prior art description. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, each element or part is not necessarily drawn according to the actual proportion.

[0024] Fig. 1 It is the overall front view structure diagram of the utility model;

[0025] Fig. 2 It is the upper high thermal conductivity pad of the utility model stereoscopic structure diagram;

[0026] Fig. 3 It is the sectional enlarged structure diagram of the utility model metallized ceramic substrate.

[0027] In the drawing, 1, metallized ceramic substrate; 2, silicon carbide chip group; 3, upper high thermal conductivity pad; 4, upper radiator; 5, lower high thermal conductivity pad; 6, lower radiator; 7, packaging shell; 8, insulation layer; 9, metalized conductive layer; 10, ceramic insulation layer; 11, conductive terminal; 12, heat-conducting silicone grease layer. DETAILED DESCRIPTION

[0028] The utility model makes further explanation in combination with the drawings and specific embodiment, help understanding the contents of the utility model. The method used in the utility model is conventional method if no special provision, the raw material and device used are conventional market products if no special provision.

[0029] Please refer to Figs. 1-3 A double-sided heat dissipation silicon carbide power module based on high-thermal-conductivity cushion block, comprising:

[0030] The metalized ceramic substrate 1 is composed of a ceramic insulating layer 10 and a metalized conductive layer 9 on the upper and lower surfaces thereof;

[0031] The silicon carbide chip set 2 is welded to the upper surface of the metalized ceramic substrate 1;

[0032] The upper heat dissipation unit covers the upper surface of the silicon carbide chip set 2 and comprises an upper high-thermal-conductivity cushion block 3 and an upper heat sink 4, wherein the upper high-thermal-conductivity cushion block 3 is attached to the upper surface of the silicon carbide chip set 2, and the upper heat sink 4 is in close contact with the upper high-thermal-conductivity cushion block 3;

[0033] The lower heat dissipation unit is located below the metalized ceramic substrate 1 and comprises a lower high-thermal-conductivity cushion block 5 and a lower heat sink 6, wherein the lower high-thermal-conductivity cushion block 5 is attached to the lower surface of the metalized ceramic substrate 1, and the lower heat sink 6 is in close contact with the lower high-thermal-conductivity cushion block 5;

[0034] The packaging shell 7 covers the outer wall of the metalized ceramic substrate 1, the silicon carbide chip set 2, the upper heat dissipation unit and the lower heat dissipation unit.

[0035] In this embodiment, the heat generated by the silicon carbide chip set 2 during operation is transferred to the upper heat sink 4 through the upper high-thermal-conductivity cushion block 3, and is also transferred to the lower heat sink 6 through the metalized ceramic substrate 1 and the lower high-thermal-conductivity cushion block 5, thereby forming a double-sided heat dissipation path. In combination with the direct contact heat transfer of the upper high-thermal-conductivity cushion block 3 and the lower high-thermal-conductivity cushion block 5, the thermal resistance is reduced, the heat dissipation is uniform, the heat dissipation effect is good, the heat is dissipated through the convection of the surface of the heat dissipation fins and the air, the heat dissipation effect is improved, the ceramic insulating layer 10 is made of aluminum nitride material, has high thermal conductivity and high strength, and has long service life, the metalized conductive layer 9 is made of metal copper, has good conductive effect, the upper high-thermal-conductivity cushion block 3 directly contacts the surface of the silicon carbide chip set 2, avoids the additional thermal resistance of the traditional welding layer, and improves the heat dissipation effect.

[0036] As a technical optimization scheme of the utility model, the material of the upper high-thermal-conductivity cushion block 3 and the lower high-thermal-conductivity cushion block 5 is one of graphene, copper composite material and elastic heat-conducting silica gel, and the surface is covered with an insulating layer 8, the insulating layer 8 is an aluminum oxide ceramic film, and the thickness of the insulating layer is 10-50 μm.

[0037] In the embodiment, the insulating layer 8 blocks the current leakage between the upper high-thermal-conductivity pad 3 and the lower high-thermal-conductivity pad 5 and the heat sink, while maintaining high thermal conductivity, the alumina ceramic film has high bonding strength with the pad, and layering failure is avoided.

[0038] As a technical optimization scheme of the utility model, the outer walls of the upper heat sink 4 and the lower heat sink 6 are fixedly connected with a plurality of uniformly distributed heat dissipation fins.

[0039] In the embodiment, heat is dissipated through the surface of the heat dissipation fins and air convection, improving the heat dissipation effect.

[0040] As a technical optimization scheme of the utility model, the ceramic insulating layer 10 is made of aluminum nitride, with a thickness of 0.3-1 mm; and the metalized conductive layer 9 is made of copper, with a thickness of 0.2-0.5 mm.

[0041] In the embodiment, the ceramic insulating layer 10 is made of aluminum nitride, with high thermal conductivity and strength, and long service life; and the metalized conductive layer 9 is made of copper, with good conductive effect.

[0042] As a technical optimization scheme of the utility model, the packaging shell 7 is made of epoxy resin, with a wall thickness of 2-5 mm; a plurality of conductive terminals 11 are arranged on the outer side wall of the packaging shell 7, and the conductive terminals 11 are ultrasonically welded with the electrodes of the metalized ceramic substrate 1.

[0043] In the embodiment, the packaging shell 7 is injection molded from high-fluidity epoxy resin, improving the protection effect of the packaging shell 7, and the conductive terminals 11 are ultrasonically welded with the electrodes of the metalized ceramic substrate 1.

[0044] As a technical optimization scheme of the utility model, a heat-conductive silicone grease layer 12 is filled between the metalized ceramic substrate 1 and the lower high-thermal-conductivity pad 5.

[0045] In the embodiment, the heat-conductive silicone grease layer 12 is filled between the metalized ceramic substrate 1 and the lower high-thermal-conductivity pad 5, with good heat conduction effect, strong high-temperature resistance, and low aging.

[0046] The working principle and use process of the utility model are as follows: the heat generated by the silicon carbide chip set 2 during work is transmitted to the upper heat sink 4 through the upper high-thermal-conductivity pad 3, and is transmitted to the lower heat sink 6 through the metalized ceramic substrate 1 and the lower high-thermal-conductivity pad 5, forming a double-sided heat dissipation path; the direct contact heat transfer of the high-thermal-conductivity upper high-thermal-conductivity pad 3 and the lower high-thermal-conductivity pad 5 reduces the thermal resistance, and the heat is evenly dissipated, with good heat dissipation effect; the heat is dissipated through the surface of the heat dissipation fins and air convection, improving the heat dissipation effect; the ceramic insulating layer 10 is made of aluminum nitride, with high thermal conductivity and strength, and long service life; the metalized conductive layer 9 is made of copper, with good conductive effect; and the upper high-thermal-conductivity pad 3 directly contacts the surface of the silicon carbide chip set 2, avoiding the additional thermal resistance of the traditional welding layer and improving the heat dissipation effect.

[0047] In the description of the utility model, need understanding is, the orientation or position relation that the terms "left", "right", "up", "down", "top", "bottom", "front", "back", "inner", "outer", "back", "intermediate" etc. indicate is based on the orientation or position relation shown in the drawing, only for the convenience of describing the utility model and simplifying the description, and is not indicating or implying that the indicated device or element must have a specific orientation, is constructed and operated in a specific orientation, therefore can not be understood as limiting the utility model.

[0048] Only the above is the specific embodiment of the utility model, and cannot limit the range of the utility model implementation, so the replacement of equivalent components, or equivalent changes and modifications made in the protection range of the utility model patent, should still belong to the scope covered by the claims of the utility model.

Claims

1. A double-sided heat dissipating silicon carbide power module based on high thermal conductivity pads, characterized by: It comprises: a metalized ceramic substrate (1) composed of a ceramic insulating layer (10) and a metalized conductive layer (9) on its upper and lower surfaces; a silicon carbide chip set (2) welded to the upper surface of the metalized ceramic substrate (1); an upper heat dissipation unit covering the upper surface of the silicon carbide chip set (2) and comprising an upper high-thermal-conductivity pad (3) and an upper heat sink (4), the upper high-thermal-conductivity pad (3) being attached to the upper surface of the silicon carbide chip set (2), and the upper heat sink (4) being in close contact with the upper high-thermal-conductivity pad (3); a lower heat dissipation unit located below the metalized ceramic substrate (1) and comprising a lower high-thermal-conductivity pad (5) and a lower heat sink (6), the lower high-thermal-conductivity pad (5) being attached to the lower surface of the metalized ceramic substrate (1), and the lower heat sink (6) being in close contact with the lower high-thermal-conductivity pad (5); an encapsulating shell (7) covering the outer walls of the metalized ceramic substrate (1), the silicon carbide chip set (2), the upper heat dissipation unit and the lower heat dissipation unit.

2. The double-sided thermal management silicon carbide power module based on high thermal conductivity spacer of claim 1, wherein: The upper high-thermal-conductivity pad (3) and the lower high-thermal-conductivity pad (5) are made of one of graphene, copper composite material and elastic heat-conducting silica gel, and have an insulating layer (8) of alumina ceramic film on their surfaces, the thickness of the insulating layer being 10-50 μm.

3. The double-sided thermal management silicon carbide power module based on high thermal conductivity spacer of claim 1, wherein: The upper heat sink (4) and the lower heat sink (6) are fixedly connected with a plurality of evenly distributed heat dissipation fins on their outer walls.

4. The double-sided thermal management silicon carbide power module based on high thermal conductivity spacer of claim 1, wherein: The ceramic insulating layer (10) is made of aluminum nitride and has a thickness of 0.3-1 mm; the metalized conductive layer (9) is made of copper and has a thickness of 0.2-0.5 mm.

5. The double-sided thermally enhanced carbonized silicon carbide power module of claim 1, wherein: The encapsulating shell (7) is made of epoxy resin and has a wall thickness of 2-5 mm, and a plurality of conductive terminals (11) are arranged on the outer wall of the encapsulating shell (7), the conductive terminals (11) being ultrasonically welded to the electrodes of the metalized ceramic substrate (1).

6. The double-sided thermally enhanced carbonized silicon carbide power module of claim 1, wherein: A heat-conducting silicone grease layer (12) is filled between the metalized ceramic substrate (1) and the lower high-thermal-conductivity pad (5).

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