MBE growth of high quality GaN on LiGaO2

Abstract

We report on the growth of high structural quality (as determined by x-ray diffraction) GaN on a near lattice matched substrate, lithium gallate (LiGaO2 or LGO). Low temperature growth conditions are described that result in very thin GaN films (<0.3 µm) with (0004) x-ray diffraction rocking curves full width at half maximum (FWHM) of 145 arc-sec and thicker films (1 µm) resulting in 85 arc-sec FWHM. The effect of growth temperature is examined and found to result in a broad minimum in x-ray FWHM around 690°C. Detailed growth conditions and descriptions of the reflection high energy electron diffraction patterns observed during growth are given. Additionally, we report very highly resistive material and doped material with bulk electron mobilities in excess of 100 cm2/V-sec.