Glow of own defects in ZnO polycrystals

Abstract

The photoluminescence of ZnO powders at room temperature upon excitation by microsecond pulses from the region of interband transitions and the region of exciton absorption has been studied. In the luminescence spectra, two regions characteristic of ZnO are observed: a short-wavelength region associated in the literature with exciton luminescence, and a long-wavelength region due to the presence of growth structural and impurity defects. The observed long-wavelength glow is divided into components with different glow durations, and several components that form this glow are identified. Experimental results and an analysis of the energy of formation and survival of the main structural defects make it possible to explain the luminescence of ZnO with allowance for the participation of only defects in the anionic sublattice and excitons in the process.