Study of photoluminescence from defects in electron-irradiated beta-Ga2O3

Research on the defects of β-Ga2O3 is the first step toward its application in high-end fields. However, there is still controversy over which defect structure is the origin of the 660–850 nm (near-infrared) photoluminescence (PL) band. The low-temperature PL spectrum was employed to study the PL properties of the 660–850 nm band. In addition, the intrinsic defects were artificially introduced into the (100) plane β-Ga2O3 crystal by electron irradiation, resulting in significant enhancement of the 660–850 nm band. Deconvolution fitting analysis combined with lattice relaxation theory indicated that the band was caused by both zero and single or multiple phonon transitions. According to the crystal structure and formation energy simulation, it was considered that the 660–850 nm PL band was related to oxygen vacancies at the three equivalent positions in the lattice.