Mg doping and diffusion in (010) beta-Ga2O3 films grown by plasma-assisted molecular beam epitaxy

In this work, we report the growth of Mg-doped (010) beta-Ga2O3 via plasma-assisted molecular beam epitaxy. Mg concentrations from 2 x 10(16) to 8 x 10(20) cm(-3) with sharp doping profiles were realized. The Mg doping incorporation in beta-Ga2O3 showed little dependence on the growth temperature and Ga:O flux ratio. Annealing at temperatures from 925 to 1050 & DEG;C resulted in significant diffusion, thus limiting the application of Mg-doped beta-Ga2O3 to lower temperature growth techniques and processing. Mg accumulation near the sample surface after diffusion gives insight into the rich point-defect interaction that may play an important role in Mg diffusion.