Semiconductor structure including a field modulation body and method for fabricating same

• US 20110049569A1
• Filed: 09/02/2009
• Published: 03/03/2011
• Est. Priority Date: 09/02/2009
• Status: Abandoned Application

• Current Assignee: Infineon Technologies Americas Corp. (Infineon Technologies AG)
• Original Assignee: International Rectifier Corporation (Infineon Technologies AG)
• Inventors: He, Zhi
• Application Number:
  US12/584,293
• Publication Number:
  US 20110049569A1
• Time in Patent Office: Days
• US Class Current: 257/192
• CPC Class Codes: H01L 29/2003 Nitride compounds
• CPC Class Codes: H01L 29/402 Field plates
• CPC Class Codes: H01L 29/4238 characterised by the surface lay-out
• CPC Class Codes: H01L 29/66219 with a heterojunction, e.g. resonant tunneling diodes [RTD]
• CPC Class Codes: H01L 29/66462 with a heterojunction interface channel or gate, e.g. HFET, HIGFET, SISFET, HJFET, HEMT
• CPC Class Codes: H01L 29/7787 with wide bandgap charge-carrier supplying layer, e.g. direct single heterostructure MODFET
• CPC Class Codes: H01L 29/861 Diodes

Abstract

According to one embodiment, a semiconductor structure including an equipotential field modulation body comprises a trench surrounding an active region of a group III-V power device fabricated in the semiconductor structure, and the equipotential field modulation body formed in the trench and extending over a portion of the active region. The equipotential field modulation body is electrically coupled to a terminal of the group III-V power device. In one embodiment, a method for fabricating a semiconductor structure including an equipotential field modulation body comprises fabricating a trench surrounding an active region of the semiconductor structure, forming the equipotential field modulation body in the trench, the equipotential field modulation body extending over a portion of the active region, and electrically coupling the equipotential field modulation body to a terminal of a group III-V power device fabricated in the active region.

Claims

1. A semiconductor structure including a field modulation body, said semiconductor structure comprising:

a trench surrounding an active region of a group III-V power device fabricated in said semiconductor structure;

said field modulation body formed in said trench and extending over a portion of said active region;

said field modulation body being electrically coupled to a terminal of said group III-V power device.

2. The semiconductor structure of claim 1, wherein said trench is fabricated in an isolation region surrounding said active region of said group III-V power device.

3. The semiconductor structure of claim 1, further comprising a trench dielectric formed in said trench and extending over said portion of said active region, said field modulation body overlying said trench dielectric.

4. The semiconductor structure of claim 1, wherein said field modulation body comprises a metal.

5. The semiconductor structure of claim 1, wherein said group III-V power device comprises a III-nitride heterostructure field-effect transistor (HFET).

6. The semiconductor structure of claim 5, wherein said terminal of said group III-V power device to which said field modulation body is electrically coupled is a gate of said III-nitride HFET.

7. The semiconductor structure of claim 1, wherein said group III-V power device comprises a III-nitride diode.

8. The semiconductor structure of claim 7, wherein said terminal of said group III-V power device to which said field modulation body is electrically coupled is an anode of said III-nitride diode.

9. The semiconductor structure of claim 1, wherein a contact pad of another terminal of said group III-V power device is formed within a perimeter determined by said field modulation body.

10. The semiconductor structure of claim 9, wherein said contact pad is either an HFET drain contact or a diode cathode contact.

11. A method comprising:

fabricating a trench surrounding an active region of a semiconductor structure, said active region including a group III-V power device;

forming a field modulation body in said trench, said field modulation body extending over a portion of said active region; and

electrically coupling said field modulation body to a terminal of said group III-V power device.

12. The method of claim 11, wherein said trench is fabricated in an isolation region surrounding said active region.

13. The method of claim 11, further comprising forming a trench dielectric in said trench and extending over said portion of said active region, said field modulation body overlying said trench dielectric.

14. The method of claim 11, wherein said field modulation body comprises a metal.

15. The method of claim 11, wherein said group III-V power device comprises a III-nitride heterostructure field-effect transistor (HFET).

16. The method of claim 15, wherein said terminal of said group III-V power device to which said field modulation body is electrically coupled is a gate of said III-nitride HFET.

17. The method of claim 11, wherein said group III-V power device comprises a III-nitride diode.

18. The method of claim 17, wherein said terminal of said group III-V power device to which said field modulation body is electrically coupled is an anode of said III-nitride diode.

19. The method of claim 11, further comprising forming a contact pad of another terminal of said group III-V power device within a perimeter determined by said field modulation body.

20. The method of claim 19, wherein said contact pad is either an HFET drain contact or a diode cathode contact.