Electronic half bridge module

• US 6,212,087 B1
• Filed: 01/31/2000
• Issued: 04/03/2001
• Est. Priority Date: 02/05/1999
• Status: Expired due to Fees

• Current Assignee: ASBU Holdings, LLC
• Original Assignee: International Rectifier Corporation (Infineon Technologies AG)
• Inventors: Grant, William, Polack, Joshua
• Primary Examiner(s): Wong, Peter S.
• Assistant Examiner(s): Laxton, Gary L.
• Application Number:
  US09/494,563
• Time in Patent Office: 428 Days
• Field of Search: 363/141, 363/144, 363/146, 363/145, 307/150, 361/679, 361/688, 361/704, 361/707, 361/714, 361/715, 361/718, 361/720, 361/722, 438/106, 438/121, 438/110, 438/133, 257/691-693, 257/696, 257/701, 257/773, 257/724, 257/704
• US Class Current: 363/144
• CPC Class Codes: H01L 2224/48472 the other connecting portion not on the bonding area also being a wedge bond, i.e. wedge-to-wedge
• CPC Class Codes: H01L 2224/49111 the connectors connecting two common bonding areas, e.g. Litz or braid wires
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/13091 Metal-Oxide-Semiconductor Field-Effect Transistor [MOSFET]
• CPC Class Codes: H02M 7/003 Constructional details, e.g. physical layout, assembly, wiring or busbar connections
• CPC Class Codes: H05K 7/1432 specially adapted for power drive units or power converters
• CPC Class Codes: H05K 7/14329 specially adapted for the configuration of power bus bars

Abstract

A metal oxide semiconductor (MOSFET) half bridge module for use in a 42 volt internal combustion engine starter/alternator circuit. The module is a compact, high power handling device which has an extremely low inductance. This low inductance module supports the current and current slew rates necessary to properly operate in an internal combustion engine starter/alternator circuit across a wide temperature range. The module has a thermally conductive base. A plurality of lower circuit boards are adjacently positioned within the base along the same plane. At least one semiconductor device has a first surface, the first surface of the semiconductor device is mounted to one of the plurality of circuit boards. A common terminal has planar portion which is coupled to each of the plurality of lower circuit boards. An upper circuit board is in electrical contact with the plurality of lower circuit boards and includes a connector providing external access for drive signals for the semiconductor device.

Claims

1. A rectifying module, comprising:

a thermally conductive base;

a plurality of lower circuit boards, each of the plurality of lower circuit boards being adjacently positioned within the thermally conductive base along a same plane;

at least one semiconductor device having a first surface, the first surface of the at least one semiconductor device being mounted to one of the plurality of lower circuit boards;

a common terminal, the common terminal having a planar portion, the planar portion being in electrical contact with each of the plurality of lower circuit boards to electrically connect the same together;

an electrical contact member; and

an upper circuit board, including a connector providing external access for drive signals for the at least on semiconductor device, the electrical contact member connecting the connector with at least one of the plurality of lower circuit boards.

2. The module according to claim 1, further comprising at least one contact pin, the contact pin being used to provide the electrical contact between the upper circuit board and one of the plurality of lower circuit boards.

3. The module according to claim 2, wherein the contact pin includes a curved portion to form a resilient contact.

4. The module according to claim 1, further comprising two voltage terminals, each of the two voltage terminals being coupled to a different one of the plurality of the lower circuit boards.

5. The module according to claim 4, wherein the two voltage terminals extend from the plurality of lower circuit boards at differing distances.

6. The module according to claim 1, wherein the at least one semiconductor device further comprises a second surface located opposite the first surface, the second surface being coupled to one of the plurality of lower circuit boards by at least one wire bond.

7. The module according to claim 6, wherein the at least one wire bond is “

S”

-shaped such that an attachment point on the one lower circuit board is angularly displaced from an attachment point on the second surface.

8. The module according to claim 7, wherein the at least one semiconductor device is a MOSFET device and the attachment point of the second surface is a source region.

9. The module according to claim 8, wherein the module forms a half bridge rectifier.

10. The module according to claim 9, wherein the module is implemented in a 42 volt internal combustion engine starter/alternator circuit.

11. The module according to claim 8, wherein a total package inductance of the module is less than approximately 8.4 nanoHenries.

12. The module according to claim 1, wherein a total thickness of the module is less than approximately 0.75 inches.

13. A half bridge rectifying module for use in an internal combustion engine starting/alternator circuit, the module comprising:

a thermally conductive base;

a plurality of lower circuit boards, each of the plurality of lower circuit boards being adjacently positioned within the thermally conductive base along a same plane;

at least one MOSFET semiconductor device having a first surface, the first surface of the at least one MOSFET semiconductor device being mounted to one of the plurality of lower circuit boards;

a common terminal, the common terminal having a planar portion, the planar portion being in electrical contact with each of the plurality of lower circuit boards to electrically connect the same;

an electrical contact member; and

an upper circuit board including a connector providing external access for drive signals for the at least one MOSFET semiconductor device, the electrical contact member connecting the connector with at least one of the plurality of lower circuit boards.

14. The half bridge rectifier module according to claim 13, further comprising two voltage terminals, each of the two voltage terminals being coupled to a different one of the plurality of the lower circuit boards.

15. The half bridge rectifier module according to claim 14, wherein the two voltage terminals extend from the plurality of lower circuit boards at differing distances.

16. The half bridge rectifier module according to claim 13, wherein the at least one MOSFET semiconductor device further comprises a second surface located opposite the first surface, the second surface being coupled to the one of the plurality of lower circuit boards by at least one wire bond.

17. The half bridge rectifier module according to claim 16, wherein the at least one wire bond is “

S”

-shaped such that an attachment point on the one of the plurality of lower circuit board is angularly displaced from an attachment point on the second surface.

18. The half bridge rectifier module according to claim 17, wherein the attachment point of the second surface is a source region.

19. The half bridge rectifier module according to claim 13, wherein a total package inductance of the module is less than approximately 8.4 nanoHenries.

20. The half bridge rectifier module according to claim 13, wherein a total thickness of the module is less than approximately 0.75 inches.

21. A rectifying module, comprising:

a thermally conductive base;

a lower circuit board positioned within the thermally conductive base;

at least one MOSFET semiconductor device having;

a first surface, the first surface of the at least one MOSFET semiconductor device being a drain surface mounted to the lower circuit board;

a second surface, the second surface being opposite the first surface and being coupled to the lower circuit board by at least one “

S”

-shaped wire bond, an attachment point on the lower circuit board being angularly displaced from an attachment point on the second surface;

a common terminal, the common terminal having a planar portion, the planar portion being in electrical contact with the lower circuit board;

a plurality of voltage terminals, each of the plurality of voltage terminals being coupled to the lower circuit board and extending at different distances therefrom;

an electrical contact member; and

an upper circuit board, including a connector providing external access for drive signals for the at least one MOSFET semiconductor device, the electrical contact member connecting the connector with the lower circuit board.

22. A module having a reduced inductance comprising:

a first circuit board and a second circuit board each having defined on an electrically conductive layer thereof a common source bus for electrical connection to a source region of at least one power semiconductor device, a common drain bus for electrical connection to a drain region of said at least one power semiconductor device, and a gate connection pad for electrical connection to a gate region of the at least one semiconductor device; and

a common terminal including an upper portion spaced from a lower portion, the lower portion being narrower than the upper portion to reduce the induction of the module, the lower portion being in electrical contact with the first and the second circuit boards.

23. The module of claim 22, further comprising a plurality of semiconductor power switching devices each having a source region thereof electrically connected to one of the common source buses of the first and second circuit boards.

24. The module of claim 22, further comprising a plurality of semiconductor power switching devices each having a drain region thereof electrically connected to one of the common drain buses of the first and second circuit boards.

25. The module of claim 22, further comprising a negative terminal and a positive terminal each in electrical contact with one of the common source bus of the second circuit board and the common drain bus of the first circuit board.

26. The module of claim 25, wherein the negative terminal and the positive terminal are positioned close to one another to reduce the inductance of the module.

27. The module of claim 23, wherein the source region on each one of the semiconductor devices is connected to the respective common source bus via at least one bonding wire.

28. The module of claim 24, wherein the gate region on each one of the semiconductor devices is connected to the respective gate connection pad via at least one bonding wire.

29. The module of claim 22, wherein at least one of the circuit boards includes a source sense pad for connecting to the source region of the at least one semiconductor device, the source sense pad being disposed near the gate pad.

30. The module of claim 22, wherein the upper portion of the common terminal is positioned over the lower portion.

31. The module of claim 22, wherein the common terminal is in electrical contact with the common source bus of the first circuit board, and the drain bus of the second circuit board.

32. The module of claim 22, wherein at least one of the circuit boards has defined on an electrically conductive layer thereof contact pads for a thermistor.

33. A module having a reduced inductance comprising:

a first circuit board and a second circuit board each having defined on an electrically conductive layer thereof a common source bus for electrical connection to a source region of at least one power semiconductor device, a common drain bus for electrical connection to a drain region of said at least one power semiconductor device, and a gate connection pad for electrical connection to a gate region of the at least one semiconductor device;

a negative terminal in electrical contact with the first circuit board; and

a positive terminal in electrical contact with the second circuit board;

wherein the positive terminal and the negative terminal are positioned close to one another to reduce the inductance of the module.

34. The module of claim 33, further comprising a common terminal including an upper portion spaced from a lower portion, the lower portion being narrower than the upper portion and in electrical contact with a contact region of the common source bus of the first circuit board, and a contact region of the drain bus of the second circuit board.

35. The module of claim 34, wherein the upper portion of the common terminal is positioned over the lower portion to reduce the inductance of the module.

36. The module of claim 35, wherein the negative terminal is in electrical contact with the common drain bus of the first circuit board, and the positive terminal is in electrical contact with the common source bus of the second circuit board.

37. A module having a reduced inductance comprising:

at least one semiconductor power switching device;

a circuit board having defined on an electrically conductive layer thereof a common source bus electrically connected to a source region of the at least one semiconductor device via at least one bond wire, the at least one bond wire being connected at a first end thereof to a source connection point on the source region of the at least one semiconductor device and connected at a second end thereof to a bus connection point on the common source bus, wherein the bond wire is shaped so that the source connection point and the bus connection point are angularly displaced so that they are not directly opposite one another to reduce the inductance of the module.

38. The module of claim 37, wherein the source connection point and the bus connection point are slightly offset to reduce the inductance of the module.

39. A rectifying module comprising:

at least one circuit board having defined on an electrically conductive layer thereof,

a common drain bus, the common drain bus including at least two substantially parallel spaced apart portions for electrical connection with a drain region of a semiconductor power device, the parallel portion being integral with a contact portion for making electrical contact with a terminal;

a common source bus substantially parallel to the parallel portions of the common drain bus and disposed therebetween for connecting to a source region of a semiconductor device, the common source bus including a contact portion for making electrical contact with another terminal; and

at least one gate pad for making electrical connection with a gate region of a semiconductor device, the gate pad being disposed near one of the parallel portions of the common drain bus.

40. The module of claim 39, further comprising a source sense pad defined on the at least one circuit board, the source pad being defined near the gate pad.

41. The module of claim 39, wherein the circuit board is an insulated metal substrate.

42. A module comprising:

a circuit board having defined on a conductive layer thereof at least one gate pad for electrical connection to a gate region of a power semiconductor device and at least one source sense pad for electrical connection with a source region of the at least one semiconductor device, wherein the gate pad and the source sense pad are disposed as closed as possible to one another to reduce the inductance of the module.

43. The module of claim 42, wherein the gate pad is connected to the gate region via a wire bond having a length, and the source sense pad is connected to the source region by another wire bond having a length, the length of the wire bonds being as short as possible to reduce the inductance of the module.