Strategies for p-type doping of ZnGeN2

Abstract

ZnGeN2 has been proposed as an attractive semiconductor for a number of applications, but doping is largely unexplored. We examine the behavior of Li, Cu, Al, Ga, In, and C as candidate acceptors using hybrid density functional theory. Cu, In, and C give rise to deep acceptor levels, but Li, Al, or Ga could potentially lead to p-type conductivity. Al is particularly attractive since it has an ionization energy of 0.24 eV, comparable to Mg in GaN. However, self-compensation due to wrong-site incorporation is a serious issue. We demonstrate that co-doping with hydrogen can be used to overcome this problem.