Impacts of Point Defects on Shallow Doping in Cubic Boron Arsenide: A First Principles Study

Cubic boron arsenide (BAs) stands out as a promising material for advanced electronics, thanks to its exceptional thermal conductivity and ambipolar mobility. However, effective control of p- and n-type doping in BAs poses a significant challenge, mostly as a result of the influence of defects. In the present study, we employed density functional theory to explore the impacts of the common point defects and impurity on p-type doping Be_B and Si_As, and n-type doping Si_B and Se_As. We find that the most favorable points defects formed by C, O, and Si are C_As, O_BO_As, Si_As, C_AsSi_B, and O_BSi_As, which have formation energies of less than 1.5 eV. For p-type doping, C, O, and Si impurities do not harm the shallow state of Be_B doping, while only O impurity detrimentally affects Si_As doping. However for n-type dopings, C, O, and Si impurities are all harmful. Interestingly, the antisite defect pair As_BB_As benefits both p- and n-type doping. The doping limitation analysis presented in this study can potentially pave the way for strategic development in the area of BAs-based electronics.