Studies of interfacial optical and electrical properties on dielectric/ZnO systems

摘要

The thermal stability of AlO_x and MgO_x on ZnO films has been studied by using photoluminescence, cathodoluminescence and current-voltage measurements. It is found that the interfaces degrade significantly upon thermal annealing, which are evident by the reduction of the band-edge emission as well as the increase of conductance with annealing temperature and duration. By using secondary ion mass spectroscopy and diffusion model, the dependence of luminescence on thermal treatment can be well simulated and the degradation of oxide/ZnO can be attributed to the out-diffusion of Zn into the oxide layer from ZnO. Our studies point out the importance of developing appropriate diffusion barrier for the fabrication of low temperature processed ZnO transistors.