Growth of high quality N-polar n-GaN on vicinal C-face n-SiC substrates for vertical conducting devices

Abstract

High quality N-polar n-type GaN films were deposited on vicinal C-face n-SiC substrates by metal organic chemical vapor deposition for vertical conducting devices. We employed the SiNx interlayer to N-polar GaN growth and studied the effect of SiNx interlayer on the properties of N-polar GaN. We found that the properties of N-polar films were greatly improved by using SiNx interlayer as characterized by X-ray diffraction, photoluminescence, and I-V measurements. N-polar n-type GaN films with SiNx interlayer exhibited a full width at half maximum of 422 arcsec for (0002) omega scan and 335 arcsec for (101¯2) omega scan, respectively. Integrated intensity ratio of near-band-edge emission and yellow-luminescence was increased by a factor of 4 by using SiNx interlayer. Besides, the resistance of the vertical structure with SiNx interlayer was reduced by 25% in comparison with that without SiNx interlayer.