Energetics and electronic structure of native point defects in α-Ga2O3

We report first-principles calculations that clarify the formation energies and charge transition levels of native point defects (Ga and O vacancies, interstitials, and a Ga vacancy-O vacancy pair) in corundum structured alpha-Ga2O3. Either under a Ga- or O-rich growth condition, the negativelycharged Ga vacancy and the positively-charged Ga interstitial on a site surrounded by six O atoms are dominant when the Fermi level approaches the conduction and valence band edges, respectively. These defects would compensate carrier electrons and holes, respectively. Ga-rich conditions relatively suppress the formation of the Ga vacancy and, therefore, are suited for extrinsic n-type doping of alpha-Ga2O3. (C) 2019 The Japan Society of Applied Physics