Gallium nitride material processing and related device structures

• US 8,343,824 B2
• Filed: 06/20/2008
• Issued: 01/01/2013
• Est. Priority Date: 04/29/2008
• Status: Expired due to Fees

• Current Assignee: MACOM Technology Solutions Holdings, Inc.
• Original Assignee: International Rectifier Corporation (Infineon Technologies AG)
• Inventors: Piner, Edwin Lanier, Johnson, Jerry Wayne, Roberts, John Claassen
• Primary Examiner(s): Lee, Cheung
• Assistant Examiner(s): JOY, JEREMY J
• Application Number:
  US12/143,727
• Publication Number:
  US 20090267188A1
• Time in Patent Office: 1,656 Days
• Field of Search: 257/613, 257/E21.001, 257/E33.001, 257/54, 257/615, 257/E21.387, 257/E33.025, 257/E33.049, 257/E29.004, 438/45, 438/189, 438/198, 438/334, 438/336, 438/370
• US Class Current: 438/189
• CPC Class Codes: H01L 21/02381 Silicon, silicon germanium, germanium
• CPC Class Codes: H01L 21/02458 Nitrides
• CPC Class Codes: H01L 21/0251 Graded layers
• CPC Class Codes: H01L 21/0254 Nitrides
• CPC Class Codes: H01L 21/02658 Pretreatments cleaning in general H01L21/02041
• CPC Class Codes: H01L 21/02664 Aftertreatments planarisation in general H01L21/304
• CPC Class Codes: H01L 29/2003 Nitride compounds
• 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 33/007 comprising nitride compounds
• CPC Class Codes: H01L 33/0093 Wafer bonding; Removal of the growth substrate
• CPC Class Codes: H01S 5/32341 blue laser based on GaN or GaP

Abstract

Gallium nitride material devices and related processes are described. In some embodiments, an N-face of the gallium nitride material region is exposed by removing an underlying region.

Claims

1. A method of forming a gallium nitride material device structure comprising;

forming a gallium nitride material region comprising first and second gallium nitride material layers, the second gallium nitride material layer situated between the first gallium nitride material layer and an underlying region, the underlying region comprising a buffer region;

forming an implanted region, at least in part, within the first gallium nitride material layer;

removing at least a portion of the underlying region to expose an N-face of the gallium nitride material region; and

forming a feature on the N-face of the gallium nitride material region;

wherein a portion of the gallium nitride material region is removed when exposing the N-face of the gallium nitride material region.

2. The method of claim 1, wherein forming a feature comprises forming a layer on the N-face of the gallium nitride material region.

3. The method of claim 1, wherein forming a feature comprises forming a contact on the N-face of the gallium nitride material region.

4. The method of claim 3, further comprising forming a source contact, a gate contact and a drain contact on the N-face of the gallium nitride material region.

5. The method of claim 1, wherein the underlying region comprises a substrate.

6. The method of claim 5, wherein the substrate comprises silicon.

7. The method of claim 1, wherein the gallium nitride material region comprises a gallium nitride channel layer.

8. The method of claim 7, wherein the N-face of the gallium nitride channel layer is exposed.

9. The method of claim 1, wherein the underlying region is removed by etching to expose an N-face of the gallium nitride material region.

10. The method of claim 1, wherein the buffer region is removed when exposing the N-face of the gallium nitride material region.

11. The method of claim 1, further comprising forming a handle region on the gallium nitride material region.

12. The method of claim 11, wherein the handle region includes a sacrificial handle portion.

13. The method of claim 12, wherein the sacrificial handle portion comprises silicon.

14. The method of claim 1, wherein the gallium nitride material region comprises an aluminum gallium nitride layer.

15. The method of claim 1, further comprising forming another implanted region, at least in part, within the gallium nitride material region.

16. The method of claim 1, further comprising stopping removal of the underlying region based on detection of implanted species from the implanted region.

17. A method comprising:

introducing a species within a structure comprising a gallium nitride material region and a region underlying the gallium nitride material region, the region underlying the gallium nitride material region comprising a buffer region, the gallium nitride material region comprising a first gallium nitride material layer and a second gallium nitride material layer, the second gallium nitride material layer situated between the first gallium nitride material layer and the buffer region, the species introduced at least into a portion of the first gallium nitride material layer;

removing a portion of the structure including the region underlying the gallium nitride material region to expose an N-face of the gallium nitride material region; and

stopping removal of the structure based on detecting an amount of the introduced species.

18. The method of claim 17, wherein the introduced species is a dopant within the gallium nitride material region.

19. The method of claim 18, wherein the introduced species is included in the buffer region.

20. The method of claim 17, wherein a portion of the gallium nitride material region is removed.

21. The method of claim 17, wherein removing the portion comprises etching.

22. The method of claim 17, wherein stopping removal of the structure is based on detection of a pre-determined amount of the species.

23. The method of claim 17, wherein stopping removal of the structure is based on a detection of a decrease in the amount of species detected.

24. The method of claim 23, stopping removal of the structure is based on a detection of a decrease in the amount of species to an undetectable amount.

25. The method of claim 17, wherein the species is silicon.

26. The method of claim 18, wherein the species is magnesium.

27. The method of claim 18, wherein the species is iron.