A Theoretical Study On Structure And Properties Of Doped Ga₂O₃

Wide bandgap semiconductor ?-Ga₂O₃ attracts much attention of researchers because of its excellent physical and chemical properties. People try to improve the performance of?-Ga₂O₃ by doping other atoms for years and get some success. The geometry, band structure and optical properties of intrinsic ?-Ga₂O₃ and Zn, Mg, Li doped ?-Ga₂O₃ were studied by the way of first-principles calculation based on density functional theory, and GGA+U exchange-correlation potential and theoretical analysis were also applied. The calculated results show the intrinsic ?-Ga₂O₃ is direct bandgap semiconductor with a band gap of4.827 eV. GGA+U is a viable calculated method with high degree of accuracy. The introduction of Zn, Mg, Li atoms makes intrinsic ?-Ga₂O₃ indirect and the band gap becomes narrow. The doping system shows half metallic characters with 100% spin polarization.Changing the value of Zn atoms U can adjust the size of the band gap of the doping system. In doping process, Mg, Li atoms are more inclined to replace the Ga atoms in octahedral site.The introduction of Zn, Mg, Li three kinds of atoms have some impact on the spin symmetry of the system, the spin symmetry is no more completely symmetrical. There is the possibility of preparing diluted magnetic semiconductors. The doping system can work in ultraviolet and deep ultraviolet region. The introduction of Zn, Mg, Li atoms increase the transmission rate and reduce the refractive index, reflectivity and absorption of ?-Ga₂O₃ in the ultraviolet region. The doping system can be used to prepare UV transparent conductive materials.