Electron beam irradiation enhanced varistor properties in ZnO nanowire

摘要

Through a combination of atomic and electronic structure characterization studies based on aberration-corrected transmission electron microscopy and varistor property tests, we quantitatively investigated the growth process and oxygen vacancy generation in ZnO quantum dots induced by irradiating ZnO nanowires with high-energy electron beams. These processes are associated with improved varistor performance in single-crystalline ZnO nanowires. Quantitative strain measurements revealed the formation of a strong tensile strain of up to 4.4% in the region of the ZnO quantum dots. Electron energy loss spectroscopy demonstrated a rapid increase in oxygen vacancies in ZnO under electron beam irradiation. These two major changes greatly decreased carrier transport, resulting in a 34% reduction in leakage current after irradiation at a beam voltage of 2 MeV. These experimental results suggest that ZnO is an exceDent semiconductor material and shows promise for practical application in electronics.