Role of Fe impurity complexes in the degradation of GaN/AlGaN high-electron-mobility transistors
Abstract
Recent experiments show that GaN/AlGaN high-electron-mobility transistors suffer from significant current collapse, which is caused by an increase in the concentration of traps with energy levels 0.5–0.6 eV below the conduction-band edge. This increase in trap concentration is consistent with thermally activated defect diffusion, but the responsible defect complexes have not been identified. It has been suggested that the defect complex may contain iron because of the proximity of the Fe-doped GaN substrate. Here, we report first-principles density-functional calculations of substitutional iron complexes, investigate their properties, and show that the FeGa-VN complex has properties that account for the observed degradation.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Feb 02, 2015
- Source ID
- 10.1063/1.4907675
Entities
People
- D. M. Fleetwood
- Ronald D. Schrimpf
- S. T. Pantelides
- Y. S. Puzyrev
Organizations
- Oak Ridge National Laboratory
- Office of Naval Research
- Vanderbilt University