First-principles calculations of effective mass of impurity-doped Ga₂O₃

Gallium oxide (Ga₂O₃) is a promising material for high-power electronic devices owing to its wide bandgap and high breakdown field; however, its relatively low carrier mobility remains one of the factors limiting device development. Since carrier mobility is fundamentally governed by the electronic band structure, understanding the intrinsic factors that determine carrier transport properties is essential. In this study, first-principles calculations were performed to investigate the effects of impurity doping on the effective masses of α- and β-Ga₂O₃. Changes in the electron and hole effective masses induced by impurity doping were analyzed through detailed band-structure calculations. Si and Sn doping were found to increase the electron effective mass in both polymorphs, whereas F doping exhibited different behaviors between the two polymorphs, showing a slight reduction in α-Ga₂O₃ and only a minor influence in β-Ga₂O₃. For hole transport in β-Ga₂O₃, N doping caused pronounced modifications in the anisotropy of the hole effective mass.