Thermal stability of deep level defects induced by high energy proton irradiation in n-type GaN
Abstract
The impact of annealing of proton irradiation-induced defects in n-type GaN devices has been systematically investigated using deep level transient and optical spectroscopies. Moderate temperature annealing (>200–250 °C) causes significant reduction in the concentration of nearly all irradiation-induced traps. While the decreased concentration of previously identified N and Ga vacancy related levels at EC − 0.13 eV, 0.16 eV, and 2.50 eV generally followed a first-order reaction model with activation energies matching theoretical values for NI and VGa diffusion, irradiation-induced traps at EC − 0.72 eV, 1.25 eV, and 3.28 eV all decrease in concentration in a gradual manner, suggesting a more complex reduction mechanism. Slight increases in concentration are observed for the N-vacancy related levels at EC − 0.20 eV and 0.25 eV, which may be due to the reconfiguration of other N-vacancy related defects. Finally, the observed reduction in concentrations of the states at EC − 1.25 and EC − 3.28 eV as a function of annealing temperature closely tracks the detailed recovery behavior of the background carrier concentration as a function of annealing temperature. As a result, it is suggested that these two levels are likely to be responsible for the underlying carrier compensation effect that causes the observation of carrier removal in proton-irradiated n-GaN.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Oct 15, 2015
- Source ID
- 10.1063/1.4933174
Entities
People
- Aaron R. Arehart
- Brian M. McSkimming
- D. M. Fleetwood
- E. C. H. Kyle
- En Xia Zhang
- Esmat Farzana
- James S. Speck
- Jiayu Chen
- Ronald D. Schrimpf
- Steven A. Ringel
- Wenyuan Sun
- Z. Zhang
Organizations
- Defense Threat Reduction Agency
- Office of Naval Research
- Ohio State University
- University of California
- Vanderbilt University