Geometrically coupled field-controlled-injection diode, voltage limiter and freewheeling diode having the geometrically coupled field-controlled-injection diode

• US 6,410,950 B1
• Filed: 04/06/1998
• Issued: 06/25/2002
• Est. Priority Date: 04/04/1997
• Status: Expired due to Term

• Current Assignee: Infineon Technologies AG
• Original Assignee: Infineon Technologies AG
• Inventors: Taghizadeh-Kaschani, Karim-Thomas, Sittig, Roland
• Primary Examiner(s): Williams, Alexander O.
• Application Number:
  US09/055,794
• Time in Patent Office: 1,541 Days
• Field of Search: 257/247, 257/483, 257/484, 257/605, 257/626, 257/105, 257/106, 257/481, 257/551, 257/603, 257/492, 257/493, 257/495, 257/170, 257/723, 257/133, 257/138, 257/137, 257/134, 257/147, 257/347, 257/349-351, 257/354, 257/655
• US Class Current: 257/267
• CPC Class Codes: H01L 29/864 Transit-time diodes, e.g. IMPATT, TRAPATT diodes
• CPC Class Codes: H01L 29/868 PIN diodes
• 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 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00

Abstract

A pin diode includes an inner zone, a cathode zone and an anode zone. A boundary surface between the inner zone and the anode zone is at least partly curved and/or at least one floating region having the same conduction type and a higher dopant concentration than in the inner zone is provided in the inner zone. The turnoff performance in such geometrically coupled power diodes, in contrast to the turnoff performance of pin power diodes (in the Read-diode version) with spaced charge coupling, is largely temperature-independent. Hybrid diodes with optimized conducting-state and turnoff performance can be made from such FCI diodes. FCI diodes are preferably used in conjunction with switching power semiconductor elements, as voltage limiters or free running diodes.

Claims

1. A power diode, comprising a semiconductor body, having:

an inner zone of a first conduction type;

a cathode zone of the first conduction type, said cathode zone adjoining said inner zone and having a higher dopant concentration than in said inner zone;

an anode zone of a second conduction type, said anode zone adjoining said inner zone and having a higher dopant concentration than in said inner zone; and

at least one floating region of the first conduction type disposed in said inner zone, said at least one floating region has a higher dopant concentration than said inner zone.

2. The power diode according to claim 1, wherein said inner zone has an anode-side area, and said at least one floating region is disposed in said anode-side area.

3. The power diode according to 1, wherein said at least one floating region at least partly borders said anode zone.

4. The power diode according to claim 1, wherein said at least one floating region is formed of conductive material.

5. The power diode according to claim 4, wherein said at least one floating region is at least partly formed of highly-doped silicon.

6. The power diode according to claim 1, including a Read-diode structure.

11. The power diode according to claim 1, wherein said at least one floating region and said anode zone defines an at least partly curved boundary surface therebetween.

12. The power diode according to claim 1, including a further boundary surface between said inner zone and said at least one floating region.

13. The power diode according to claim 1, wherein said at least one floating region is not connected to said anode zone.

7. A hybrid diode configuration, comprising a power diode including a semiconductor body, having:

an inner zone of a first conduction type;

a cathode zone of the first conduction type, said cathode zone adjoining said inner zone and having a higher dopant concentration than in said inner zone;

an anode zone of a second conduction type, said anode zone adjoining said inner zone and having a higher dopant concentration than in said inner zone; and

at least one floating region of the first conduction type disposed in said inner zone, said at least one floating region has a higher dopant concentration than said inner zone.

8. A voltage limiter, comprising a power diode including a semiconductor body, having:

an inner zone of a first conduction type;

a cathode zone of the first conduction type, said cathode zone adjoining said inner zone and having a higher dopant concentration than in said inner zone;

an anode zone of a second conduction type, said anode zone adjoining said inner zone and having a higher dopant concentration than in said inner zone; and

at least one floating region of the first conduction type disposed in said inner zone, said at least one floating region has a higher dopant concentration than said inner zone.

9. A freewheeling diode, comprising a power diode including a semiconductor body, having:

an inner zone of a first conduction type;

a cathode zone of the first conduction type, said cathode zone adjoining said inner zone and having a higher dopant concentration than in said inner zone;

an anode zone of a second conduction type, said anode zone adjoining said inner zone and having a higher dopant concentration than in said inner zone; and

at least one floating region of the first conduction type disposed in said inner zone, said at least one floating region has a higher dopant concentration than said inner zone.

10. A power diode assembly, comprising a semiconductor body including:

a power diode having an inner zone of a first conduction type, a cathode zone of the first conduction type, said cathode zone adjoining said inner zone and having a higher dopant concentration than in said inner zone, an anode zone of a second conduction type, said anode zone adjoining said inner zone and having a higher dopant concentration than in said inner zone, and at least one floating region of the first conduction type disposed in said inner zone; and

a power semiconductor component connected parallel to said power diode.

14. A power diode, comprising a semiconductor body, having:

an inner zone of a first conduction type;

a cathode zone of the first conduction type, said cathode zone adjoining said inner zone and having a higher dopant concentration than in said inner zone;

an anode zone of a second conduction type, said anode zone adjoining said inner zone and having a higher dopant concentration than in said inner zone; and

at least one floating region of the first conduction type disposed in said inner zone, said inner zone has an anode-side area, and said at least one floating region is disposed in said anode-side area.

15. The power diode according to claim 14, wherein said at least one floating region has a higher dopant concentration than said inner zone.

16. The power diode according to claim 14, wherein said at least one floating region at least partly borders said anode zone.

17. The power diode according to claim 14, wherein said at least one floating region is formed of conductive material.

18. The power diode according to claim 17, wherein said at least one floating region is at least partly formed of highly-doped silicon.

19. The power diode according to claim 14, including a Read-diode structure.

20. The power diode according to claim 14, wherein said at least one floating region has a higher dopant concentration than said inner zone and said anode zone defines an at least partly curved boundary surface therebetween.

21. The power diode according to claim 14, including a further boundary surface between said inner zone and said at least one floating region.

22. The power diode according to claim 14, wherein said at least one floating region is not connected to said anode zone.

23. A power diode, comprising a semiconductor body, having:

an inner zone of a first conduction type;

a cathode zone of the first conduction type, said cathode zone adjoining said inner zone and having a higher dopant concentration than in said inner zone;

an anode zone of a second conduction type, said anode zone adjoining said inner zone and having a higher dopant concentration than in said inner zone; and

at least one floating region of the first conduction type disposed in said inner zone and at least partly borders said anode zone.

24. The power diode according to claim 23, wherein said at least one floating region has a higher dopant concentration than said inner zone.

25. The power diode according to claim 23, wherein said inner zone has an anode-side area, and said at least one floating region is disposed in said anode-side area.

26. The power diode according to claim 23, wherein said at least one floating region is formed of conductive material.

27. The power diode according to claim 26, wherein said at least one floating region is at least partly formed of highly-doped silicon.

28. The power diode according to claim 23, including a Read-diode structure.

29. The power diode according to claim 23, wherein said at least one floating region has a higher dopant concentration than said inner zone and said anode zone defines an at least partly curved boundary surface therebetween.

30. The power diode according to claim 23, including a further boundary surface between said inner zone and said at least one floating region.

31. The power diode according to claim 23, wherein said at least one floating region is not connected to said anode zone.

32. A power diode, comprising a semiconductor body, having:

an inner zone of a first conduction type;

a cathode zone of the first conduction type, said cathode zone adjoining said inner zone and having a higher dopant concentration than in said inner zone;

an anode zone of a second conduction type, said anode zone adjoining said inner zone and having a higher dopant concentration than in said inner zone; and

at least one floating region of the first conduction type disposed in said inner zone, said at least one floating region is formed of conductive material and is at least partly formed of highly-doped silicon.

33. The power diode according to claim 32, wherein said at least one floating region has a higher dopant concentration than said inner zone.

34. The power diode according to claim 32, wherein said inner zone has an anode-side area, and said at least one floating region is disposed in said anode-side area.

35. The power diode according to claim 32, wherein said at least one floating region at least partly borders said anode zone.

36. The power diode according to claim 32, including a Read-diode structure.

37. The power diode according to claim 32, wherein said at least one floating region has a higher dopant concentration than said inner zone and said anode zone defines an at least partly curved boundary surface therebetween.

38. The power diode according to claim 32, including a further boundary surface between said inner zone and said at least one floating region.

39. The power diode according to claim 32, wherein said at least one floating region is not connected to said anode zone.

40. A power diode, comprising a semiconductor body, having:

an inner zone of a first conduction type;

a cathode zone of the first conduction type, said cathode zone adjoining said inner zone and having a higher dopant concentration than in said inner zone;

an anode zone of a second conduction type, said anode zone adjoining said inner zone and having a higher dopant concentration than in said inner zone;

at least one floating region of the first conduction type disposed in said inner zone; and

a further boundary surface between said inner zone and said at least one floating region.

41. The power diode according to claim 40, wherein said at least one floating region has a higher dopant concentration than said inner zone.

42. The power diode according to claim 40, wherein said inner zone has an anode-side area, and said at least one floating region is disposed in said anode-side area.

43. The power diode according to claim 40, wherein said at least one floating region at least partly borders said anode zone.

44. The power diode according to claim 40, wherein said at least one floating region is formed of conductive material.

45. The power diode according to claim 44, wherein said at least one floating region is at least partly formed of highly-doped silicon.

46. The power diode according to claim 40, including a Read-diode structure.

47. The power diode according to claim 40, wherein said at least one floating region has a higher dopant concentration than said inner zone and said anode zone defines an at least partly curved boundary surface therebetween.

48. The power diode according to claim 40, wherein said at least one floating region is not connected to said anode zone.

49. A power diode, comprising a semiconductor body, having:

an inner zone of a first conduction type;

a cathode zone of the first conduction type, said cathode zone adjoining said inner zone and having a higher dopant concentration than in said inner zone;

an anode zone of a second conduction type, said anode zone adjoining said inner zone and having a higher dopant concentration than in said inner zone; and

at least one floating region of the first conduction type disposed in said inner zone, said at least one floating region is not connected to said anode zone.

50. The power diode according to claim 49, wherein said at least one floating region has a higher dopant concentration than said inner zone.

51. The power diode according to claim 49, wherein said inner zone has an anode-side area, and said at least one floating region is disposed in said anode-side area.

52. The power diode according to claim 49, wherein said at least one floating region at least partly borders said anode zone.

53. The power diode according to claim 49, wherein said at least one floating region is formed of conductive material.

54. The power diode according to claim 53, wherein said at least one floating region is at least partly formed of highly-doped silicon.

55. The power diode according to claim 49, including a Read-diode structure.

56. The power diode according to claim 49, wherein said at least one floating region has a higher dopant concentration than said inner zone and said anode zone defines an at least partly curved boundary surface therebetween.

57. The power diode according to claim 49, including a further boundary surface between said inner zone and said at least one floating region.

58. A power diode, comprising a semiconductor body, having:

an inner zone of a first conduction type;

a cathode zone of the first conduction type, said cathode zone adjoining said inner zone and having a higher dopant concentration than in said inner zone;

an anode zone of a second conduction type, said anode zone adjoining said inner zone and having a higher dopant concentration than in said inner zone; and

at least one floating region of the first conduction type disposed in said inner zone, said at least one floating region and said anode zone defines an at least partly curved boundary surface therebetween.

59. A power diode, comprising a semiconductor body, having:

an inner zone of a first conduction type;

a cathode zone of the first conduction type, said cathode zone adjoining said inner zone and having a higher dopant concentration than in said inner zone;

an anode zone of a second conduction type, said anode zone adjoining said inner zone and having a higher dopant concentration than in said inner zone; and

at least one floating region of the first conduction type disposed in said inner zone and formed of a conductive metal or metal silicide.