Dopants and Defects in InN and InGaN Alloys
We have performed systematic studies of the effects of high-energy particle irradiation on the properties of InGaN alloys. In agreement with the amphoteric defect model, irradiation of InN produces donor-like defects. The electron concentration increases with increasing radiation dose and saturates at 4 x 10{sup 20} cm{sup -3} at very high doses. We find that the increase of the electron concentration causes a large blue-shift of the absorption edge, which is well-explained by the Burstein-Moss effect. The maximum electron concentration decreases with increasing Ga fraction in irradiated In{sub 1-x}Ga{sub x}N alloys as the conduction band edge approaches the Fermi level stabilization energy (E{sub FS}). For x > 0.66 the conduction band edge moves above E{sub FS} and the irradiation of n-type films produces acceptor-like defects, resulting in a reduced free electron concentration. An analysis of the concentration dependence of the electron mobility in InN indicates that the dominant defects in irradiated InN are triply-charged donors. Finally, we show that InN films doped with Mg acceptors behave like undoped films above a threshold radiation dose.
- Research Organization:
- Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
- Sponsoring Organization:
- USDOE Director. Office of Science. Office of Basic EnergySciences. Materials Sciences and Engineering Division; Department ofDefense. Office of Naval Research Contract N000149910936
- DOE Contract Number:
- DE-AC02-05CH11231
- OSTI ID:
- 889899
- Report Number(s):
- LBNL-59187; R&D Project: 513360; BnR: KC0201030; TRN: US200620%%80
- Resource Relation:
- Conference: AFOSR Indium Nitride Workshop 2, Kona, Hawaii,January 9-13, 2005
- Country of Publication:
- United States
- Language:
- English
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