First-principles investigation of the influence of point defect on the electronic and optical properties of α-Ga2O3

The Ga2O3 is a promising semiconductor, which is used in electric vehicles and 5G. However, the role of point defect of alpha-Ga2O3 is unknown. To solve the problem, here, the influence of vacancy on the electronic and optical properties of alpha-Ga2O3 is studied by the first-principles calculations. Two typical vacancies, O vacancy and Ga vacancy, were designed. The calculated results show that the alpha-Ga2O3 prefers to form O vacancy in comparison to the Ga vacancy. Furthermore, the calculated band gap of alpha-Ga2O3 is 2.970 eV. However, the calculated band gap of O vacancy and Ga vacancy is 3.556 and 3.201 eV, which is bigger than the perfect alpha-Ga2O3. Essentially, the wide band gap is that the removed atom results in a band shift from the Fermi level to the high-energy regions. The change of band gap of these oxides is affirmed by the dielectric function. Finally, it is found that the alpha-Ga2O3 oxide shows ultraviolet properties, which are in good agreement with the Ping and Berhanuddin's result. However, the calculated optical adsorption coefficient shows that the O vacancy induces the movement from the ultraviolet region to the visible light. The O vacancy and Ga vacancy weaken the storage optical properties of alpha-Ga2O3 based on the analysis of loss function functional.

Automated summary

The influence of vacancies on the electronic and optical properties of alpha-Ga2O3 semiconductor was studied using first-principles calculations. The results demonstrated that vacancies have a significant impact on the band gap and optical properties of alpha-Ga2O3.