High-Frequency and High-Power Performance of n -Type GaN Epilayers with Low Electron Density Grown on Native Substrate.

The n -type GaN epilayers with low electron density were developed on a native substrate using the metalorganic vapour phase epitaxy method and investigated under pulsed electric fields until material breakdown and optically in the spectrum range from 0.1 THz to 60 THz at two temperatures of 77 K and 300 K. The epilayers demonstrated the low-field electron mobility and density values reaching up to 1021 cm 2 /V·s and 1.06 × 10 16 cm -3 (at 300 K) and 2652 cm 2 /V·s and 0.21 × 10 16 cm -3 (at 77 K), respectively. Maximum injected electric power value till the damage of the GaN epilayer was found to be up to 1.8 GW/cm 3 and 5.1 GW/cm 3 at 77 K and 300 K, respectively. The results indicate new practical possibilities of the GaN material controlled by an external electric field.