Power electronic assembly and method of producing thereof

Patent metadata

Field	Value
Publication number	US-11632860-B2
Application number	US-201916663947-A
Country	US
Kind code	B2
Filing date	Oct 25, 2019
Priority date	Oct 25, 2019
Publication date	Apr 18, 2023
Grant date	Apr 18, 2023

Abstract

A power electronic assembly includes a board having metal layers laminated onto or between electrically insulating layers, and a power device embedded in the board. A first metal layer provides electrical contacts at a first side of the board. A second metal layer provides a thermal contact at a second side of the board. A third metal layer is positioned between the first metal layer and the power device and configured to distribute a load current switched by the power device. A fourth metal layer is positioned between the second metal layer and the power device and configured as a primary thermal conduction path for heat generated by the power device during switching of the load current. A first electrically insulating layer separates the fourth metal layer from the second metal layer so that the fourth metal layer is electrically isolated from but thermally connected to the second metal layer.

First claim

What is claimed is:

1. A power electronic assembly, comprising:
a board comprising a plurality of metal layers laminated onto or between electrically insulating layers; and
a power device embedded in the board and configured to switch a load current,
wherein a first metal layer of the board provides electrical contacts at a first side that is an outer surface of the board,
wherein a second metal layer of the board provides a thermal contact at a second side that is an outer surface of the board opposite the first side,
wherein a third metal layer of the board is positioned between the first metal layer and the power device and configured to distribute the load current switched by the power device,
wherein a fourth metal layer of the board is positioned between the second metal layer and the power device and configured as a primary thermal conduction path for heat generated by the power device during switching of the load current,
wherein a first electrically insulating layer of the board separates the fourth metal layer from the second metal layer so that the fourth metal layer is electrically isolated from but thermally connected to the second metal layer.

2. The power electronic assembly of claim 1 , wherein the fourth metal layer is thicker than both the first metal layer and the second metal layer.

3. The power electronic assembly of claim 1 , wherein the fourth metal layer has a thickness in a range of 2.1 to 4.3 times a thickness of the first metal layer and/or a thickness of the second metal layer.

4. The power electronic assembly of claim 1 , wherein the first metal layer and the second metal layer each have a thickness in a range of 35 μm to 70 μm, and wherein the fourth metal layer has a thickness in a range of 75 μm to 150 μm.

5. The power electronic assembly of claim 1 , wherein the first electrically insulating layer of the board is a layer of fiberglass impregnated with resin and has a thickness selected to electrically isolate the fourth metal layer from the second metal layer.

6. The power electronic assembly of claim 5 , wherein the layer of fiberglass impregnated with resin has a thickness in a range of 50 μm to 500 μm.

7. The power electronic assembly of claim 5 , wherein the layer of fiberglass impregnated with resin has a thickness in a range of 50 μm to 100 μm.

8. The power electronic assembly of claim 1 , wherein the first electrically insulating layer of the board comprises a different material than the other electrically insulating layers of the board.

9. The power electronic assembly of claim 1 , wherein the first electrically insulating layer of the board has a thermal conductivity greater than a thermal conductivity of the other electrically insulating layers, wherein the thermal conductivity of the first electrically insulating layer of the board is at least 2 W/mK, and wherein the other electrically insulating layers of the board each have a thermal conductivity of less than 2 W/mK.

10. The power electronic assembly of claim 1 , wherein the third metal layer comprises a first segment configured to carry the load current to the power device and a second segment configured to carry the load current away from the power device, wherein the first segment is electrically isolated from the second segment, and wherein the board further comprises a vertical structure electrically connecting the fourth metal layer to the second segment of the third metal layer.

11. A power electronic assembly, comprising:
a board comprising a plurality of metal layers laminated onto or between electrically insulating layers; and
a power device embedded in the board and configured to switch a load current,
wherein a first metal layer of the board provides electrical contacts at a surface of a first side that is an outer surface of the board,
wherein a second metal layer of the board provides a thermal contact at a surface of a second side that is an outer surface of the board opposite the first side,
wherein a third metal layer of the board is positioned between the first metal layer and the power device and configured to distribute the load current switched by the power device,
wherein a fourth metal layer of the board is positioned between the second metal layer and the power device and configured as a primary thermal conduction path for heat generated by the power device during switching of the load current,
wherein a first electrically insulating layer of the board separates the fourth metal layer from the second metal layer so that the fourth metal layer is electrically isolated from but thermally connected to the second metal layer.

12. The power electronic assembly of claim 11 , wherein the fourth metal layer is thicker than both the first metal layer and the second metal layer.

13. The power electronic assembly of claim 11 , wherein the fourth metal layer has a thickness in a range of 2.1 to 4.3 times a thickness of the first metal layer and/or a thickness of the second metal layer.

14. The power electronic assembly of claim 11 , wherein the first metal layer and the second metal layer each have a thickness in a range of 35 μm to 70 μm, and wherein the fourth metal layer has a thickness in a range of 75 μm to 150 μm.

15. The power electronic assembly of claim 11 , wherein the first electrically insulating layer of the board is a layer of fiberglass impregnated with resin and has a thickness selected to electrically isolate the fourth metal layer from the second metal layer.

16. The power electronic assembly of claim 15 , wherein the layer of fiberglass impregnated with resin has a thickness in a range of 50 μm to 500 μm.

17. The power electronic assembly of claim 15 , wherein the layer of fiberglass impregnated with resin has a thickness in a range of 50 μm to 100 μm.

18. The power electronic assembly of claim 11 , wherein the first electrically insulating layer of the board comprises a different material than the other electrically insulating layers of the board.

19. The power electronic assembly of claim 11 , wherein the first electrically insulating layer of the board has a thermal conductivity greater than a thermal conductivity of the other electrically insulating layers, wherein the thermal conductivity of the first electrically insulating layer of the board is at least 2 W/mK, and wherein the other electrically insulating layers of the board each have a thermal conductivity of less than 2 W/mK.

20. The power electronic assembly of claim 11 , wherein the third metal layer comprises a first segment configured to carry the load current to the power device and a second segment configured to carry the load current away from the power device, wherein the first segment is electrically isolated from the second segment, and wherein the board further comprises a vertical structure electrically connecting the fourth metal layer to the second segment of the third metal layer.

Assignees

• Infineon Technologies Ag

Inventors

• Palm Petteri
• Benisek Martin
• Chen Liu
• Daeche Frank
• Maerz Josef

Classifications

• H10W74/00

  Encapsulations, e.g. protective coatings · CPC title

• H10W72/884

  Die-attach connectors and bond wires · CPC title

• H10W72/874

  On different surfaces · CPC title

• H10W72/944

  Dispositions of multiple bond pads · CPC title

• H10W72/926

  Multiple bond pads having different sizes · CPC title