Native point defects and low p-doping efficiency in Mg2(Si,Sn) solid solutions: A hybrid-density functional study

We perform hybrid-density functional calculations to investigate the charged defect formation energy of native point defects in Mg2Si, Mg2Sn, and their solid solutions. The band gap correction by is found be critical determine density these materials. For Mg interstitials are dominant provide unintentional n-type conductivity. Additionally, as vacancies can dominate Mg-poor p-type conductivity possible for Mg2Sn. However, existence low such MgSn1+ IMg2+ Mg2Sn diffusion cause severe charge compensation hole carriers resulting doping efficiency thermal degradation. Our results indicate that, addition extrinsic strategy, alloying with Mg2Si under conditions would necessary enhance less compensation.