Polarization mechanism of oxygen vacancy and its influence on dielectric properties in ZnO

We report on the mechanism of the dielectric properties of oxygen vacancy in ZnO, using ab initio numerical simulations of oxygen vacancy on the band structure and dielectric properties, to develop photoelectric material applications. It is revealed that the appearance of oxygen vacancies leads to wider energy band gap, obvious blue shift and increase in the peak of dielectric function as compared to the intrinsic ZnO simulation. We explain these unusual phenomena and analyze the dielectric changes with the mechanism of polarization in the semiconductors. It is shown that the main mechanism of influencing dielectric properties is the electron displacement polarization. The result may be helpful for development of photoelectric materials.