First-principles study of point defects in LiGaO2

The native point defects are studied in LiGaO2 using hybrid functional calculations. We find that the relative energy of formation of the cation vacancies and the cation antisite defects depends strongly on the chemical potential conditions. The lowest energy defect is found to be the Ga-Li(2+) donor. It is compensated mostly by V-Li(-1) and in part by Li-Ga(-2) in the more Li-rich conditions. The equilibrium carrier concentrations are found to be negligible because the Fermi level is pinned deep in the gap and this is consistent with insulating behavior in pure LiGaO2. V-Ga has high energy under all reasonable conditions. Both Ga-Li and V-O are found to be negative U centers with deep 2+ /0 transition levels. Published under license by AIP Publishing.