POWER MODULE WITH HOUSED POWER SEMICONDUCTORS FOR CONTROLLABLE ELECTRICAL POWER SUPPLY OF A CONSUMER, AND METHOD FOR PRODUCING SAME

Abstract

A power module for the controllable electrical power supply of a consumer includes a plurality of housed power semiconductors each with an electrically non-insulated heat discharge surface, a printed circuit board, a heat sink, one or more insulation plates, wherein the printed circuit board is arranged on a side of the power semiconductor in an orthogonal direction opposite the heat sink, wherein the insulation plate is arranged between the housed power semiconductors and a cooling surface of the heat sink, wherein one insulation plate in each case is interlockingly connected by one side to one electrically non-insulated heat discharge surface of a housed power semiconductor and is interlockingly connected by the other side to the heat sink.

Claims

1. A power module for controllable electrical power supply of a consumer, wherein the power module has: a plurality of housed power semiconductors each comprising an electrically non-insulated heat dissipation surface; a printed circuit board; a heat sink; and at least one insulation plate wherein the printed circuit board is arranged on a side of the power semiconductors which is opposite to the heat sink in an orthogonal direction, wherein the at least one insulation plate is arranged between the housed power semiconductors and a cooling surface of the heat sink, and wherein the at least one insulation plate is connected with one side to a electrically non-insulated heat dissipation surface of at least one housed power semiconductor of the plurality of housed power semiconductors in a form-fitting manner and is connected with another side to the heat sink in a form-fitting manner.

2. The power module as claimed in claim 1, wherein the at least one insulation plate has an electrically conductive metallization on a side facing the at least one housed power semiconductor and on a side facing the cooling surface of the heat sink.

3. The power module as claimed in claim 1 wherein the at least one insulation plate is made of a ceramic.

4. The power module as claimed in claim 1 further comprising connection elements that electrically contact connecting surfaces on the printed circuit board and run parallel to the connecting surfaces.

5. The power module as claimed in claim 1 further comprising connection elements that electrically contact connecting surfaces in through holes of the printed circuit board.

6. The power module as claimed in claim 1, wherein the power module has a sealant which covers the plurality of housed power semiconductors and at least partial regions of the printed circuit board against an environment.

7. A method for producing a power module, the method comprising: providing a heat sink; fitting at least one first solder preform onto a cooling surface of the heat sink; fitting at least one insulation plate onto the at least one first solder preform; fitting at least one second solder preform onto the at least one insulation plate; fitting at least one housed power semiconductor with an electrically non-insulated heat dissipation surface onto the at least one second solder preform; and carrying out a soldering process in which the at least one insulation plate is soldered to the at least one housed power semiconductor and to the heat sink.

8. The method as claimed in claim 7, further comprising: providing a printed circuit board that is connected to connection elements of the at least one housed power semiconductor.

9. The method as claimed in claim 7, wherein the at least one insulation plate has an electrically conductive metallization on a side facing the at least one housed power semiconductor and on a side facing the cooling surface of the heat sink

10. The method as claimed in claim 7, wherein the at least one insulation plate is made of a ceramic.

11. The method as claimed in claim 8, wherein the connection elements run parallel to connecting surfaces of the printed circuit board.

12. The method as claimed in claim 8, wherein the connection elements electrically contact connecting surfaces of the printed circuit board in through holes of the printed circuit board.

13. The method as claimed in claim 8, further comprising: covering the plurality of housed power semiconductors and at least partial regions of the printed circuit board against an environment a sealant.

Description

[0033] Exemplary embodiments of the invention are described in a detailed manner hereinafter with reference to the accompanying figures.

[0034] FIGS. 1 and 2 show sectional views through power modules according to different embodiments of the present invention.

[0035] FIG. 3 shows a schematic sequence of the method according to the invention.

[0036] There reference numbers used in the figures and their meaning are listed in summary form in the list of reference numbers. In principle, identical or similar parts are provided with the same reference numbers. The figures are merely schematic and not to scale.

[0037] FIGS. 1 and 2 each show sectional views through a power module 1 for controllable electrical power supply of a consumer (not represented) such as an electric motor in an electrically driven vehicle, for example. FIG. 2 shows a sectional view through a slightly modified variant of the power module 1 from FIG. 1.

[0038] The power module 1 comprises a plurality of housed power semiconductors 3, a plurality of insulation plates 50, a printed circuit board 5, a heat sink 7, as well as a sealant 9. The heat sink 7 can be designed as a cooling plate made of a metal such as copper, for example, and may optionally possess cooling structures 21. Electrical and/or electronic components 11 are provided on the printed circuit board 5 which form a control circuit 13 for controlling the power semiconductors 3. Electrical power can, for example, be fed in from a battery via external connections (not represented) and then delivered, controlled by the power module 1, via other external connections (not represented), to motor phases of an electric motor, for example.

[0039] Each of the power semiconductors 3 has a heat dissipation surface 15 on its outer side directed toward the heat sink 7. On this heat dissipation surface 15, on the housed power semiconductor 3, a metallic surface or plate is provided, via which heat which is generated inside the housed power semiconductor 3, for example by a power-controlling semiconductor component located there such as an IGBT, a SiC or a power MOSFET, can be discharged.

[0040] In this case, the housed power semiconductors 3 each possess electrically conductive connection elements 23. The connection elements 23 are used to electrically connect power-controlling structures, for example in the form of semiconductor components inside the housed power semiconductors 3, in order to provide them with control signals and/or the electrical power which is to be controlled.

[0041] Each of the housed power semiconductors 3 is connected to an insulation plate 50. In this case, the insulation plate 50 is arranged between the housed power semiconductor 3 and the heat sink 7. The insulation plate 50 has a metallization 51 on an upper side 51a facing the housed power semiconductor 3 and on a lower side 51b facing the heat sink 7 respectively. Solder preforms 52 are further arranged between the metallization 51 and the housed power semiconductor 3 as well as between the metallization 51 and the heat sink 7 respectively.

[0042] The solder preforms 52 are thermally connected to the metallizations 51 on the respective sides 51a, 51b of the insulation plate 50. During a soldering process, on the one side 51a of the insulation plate 50, the solder preforms 52 connect the insulation plate 50 to the heat dissipation surface 15 of the power semiconductor 3. On the other side 51b of the insulation plate, the solder preforms 52 connect the insulation late 50 to the cooling surface 17 of the heat sink 7. The insulation plate 50 is therefore connected to the cooling surface 17 of the heat sink 7 in a thermally conductive manner. Furthermore, the heat dissipation surface 15 of the housed power semiconductor 3 is connected to the cooling surface 17 of the heat sink 7 in a thermally conductive manner via the insulation plate 50.

[0043] The printed circuit board 5 is arranged on a side of the power semiconductors 3 which is opposite in an orthogonal direction to the side on which the heat sink 7 is arranged. In other words, the power semiconductors 3 are located between the heat sink 7 and the printed circuit board 5.

[0044] The connection elements 23 of the power semiconductors 3 are arranged in such a way that the connection elements 23 electrically contact connecting surfaces 25 on the printed circuit board 5. In the embodiment represented in FIG. 1, the elongated connection elements 23 are arranged laterally adjacent to the power semiconductor 3 for this purpose and contact the connecting surfaces 25 there.

[0045] FIG. 2 shows a variant of the embodiment represented in FIG. 1. In order to avoid repetitions, only the changes to FIG. 1 are mentioned in the description of FIG. 2.

[0046] The printed circuit board 5 has through holes 60. These through holes 60, also referred to as vias or via holes, have a metallization and therefore serve as connecting surfaces 25 for the connection elements 23 of the power semiconductors 3, in addition to connecting surfaces 25 on the lower and/or upper side of the printed circuit board 5. In this case, the through holes 60 are designed in such a way that the connection elements 23 can reach through the printed circuit board 5. This makes it possible for the connection elements 23 to be able to be attached, for example soldered, to the connecting surfaces 25 on a side of the printed circuit board 5 which is opposite to the power semiconductors 3.

[0047] FIG. 3 shows a schematic sequence of the method according to the invention.

[0048] In a first method step S1, a heat sink 7 is provided. In a step S2, the cooling surface 17 of the heat sink 7 is subsequently fitted with one or a plurality of solder preforms 52. These solder preforms 52 are fitted with insulation plates 50 in a third step S3. In a fourth step S4, the insulation plates 50 are subsequently fitted with solder preforms 52. In a subsequent fitting step S5, the housed power semiconductors 3 with the electrically non-insulated heat dissipation surface 15 are arranged on the solder preforms 52.

[0049] In a subsequent soldering process S6, the solder preforms 52 are melted in such a way that the insulation plates 50 are soldered to the housed power semiconductors 3 and to the heat sink 7. As a result, a thermal connection between the heat dissipation surface 15 of the power semiconductors 3 and the heat sink 7 is achieved.

[0050] In a step S7, a printed circuit board 5 is provided and in a step S8, the connection elements of the housed power semiconductors are connected to the printed circuit board 5.

[0051] In addition, it should be noted that “comprising” does not exclude any other elements or steps and “a” does not exclude a multiplicity. It should further be noted that features or steps that have been described with reference to one of the previous exemplary embodiments can also be used in combination with other features or steps from other exemplary embodiments described previously. Reference numbers in the claims are not to be regarded as a limitation.

REFERENCE NUMBERS

[0052] 1 power module

[0053] 3 power semiconductor

[0054] 5 printed circuit board

[0055] 7 heat sink

[0056] 9 sealant

[0057] 11 components

[0058] 13 control circuit

[0059] 15 heat dissipation surface

[0060] 17 cooling surface

[0061] 21 cooling structures

[0062] 23 connection elements

[0063] 25 connecting surfaces

[0064] 50 insulation plate

[0065] 51 metallization

[0066] 51a upper side of the insulation plate der

[0067] 51b lower side of the insulation plate

[0068] 52 solder preform

[0069] 60 through hole

[0070] S1-S8 method steps