Dopants and Defects in InN and InGaN Alloys

Conference · Fri Apr 01 04:00:00 EST 2005

OSTI ID:889899

Walukiewicz, W; Jones, R E; Li, S X; Yu, K M; Ager, III, J W; Haller, E E; Lu, H; Schaff, W J

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: Ernest Orlando Lawrence Berkeley NationalLaboratory, Berkeley, CA (US)
• 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: AC02-05CH11231
• OSTI ID: 889899
• Report Number(s): LBNL--59187; BnR: KC0201030
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ABSORPTION
ALLOYS
DEFECTS
ELECTRON MOBILITY
ELECTRONS
FERMI LEVEL
INDIUM NITRIDES
IRRADIATION
RADIATION DOSES
STABILIZATION