Incorporation of Carbon in Free-Standing HVPE-Grown GaN Substrates
- 4 Downloads
Carbon doping is a viable approach for compensating the unintentional donors in GaN and achieving semi-insulating substrates necessary for high-frequency, high-power devices. In this work, bulk material properties and point defects are studied in mm-thick free-standing carbon-doped GaN to understand the efficacy of the carbon dopant. Temperature-dependent Hall measurements reveal high resistivity and low carrier concentrations at temperatures as high as 560°C in a 6 × 1017 cm−3 C-doped sample, and electron paramagnetic resonance (EPR) indicates that carbon acts as the compensating defect. Photoluminescence, in agreement with photo-EPR, suggests that the compensating center is CN; however, additional defects, which possibly limit compensation, are formed at carbon concentrations greater than 5 × 1017 cm−3.
KeywordsGaN carbon hydride vapor phase epitaxy electron paramagnetic resonance photoluminescence Hall effect
Unable to display preview. Download preview PDF.
The work performed at NRL was supported by the Office of Naval Research and that at UAB by NSF DMR-1606765. We also thank Dr. Jack Lyons (NRL) for helpful discussions and Mr. Will Willoughby for some data analysis. The research in Poland was supported by the Department of the Navy, Office of Naval Research (ONRG-NICOP-N62909-17-1-2004) and by the Polish National Science Center through Project No. 2017/25/B/ST5/02897.
- 19.J.A. Weil, J.R. Bolton, and J.E. Wertz, Elementary Theory and Practical Applications (New York: Wiley, 1994).Google Scholar