Varying Photoconductivity of ZnO as a Function of Annealing Temperature

Abstract

Arsenic has been doped in MOCVD grown ZnO thin films using thermal diffusion technique from semi-insulating GaAs substrate. Hall measurements showed p-type conductivity in ZnO. XPS analyses reveal that AsZn–VZn is the shallow acceptor complex which contributes p-type conductivity of the films. As the post-growth annealing temperature increased from 600 0C to 700 0C the hole concentration also increased from 1.1x1018 cm-3 to 2.8x1019 cm-3 respectively. It shows an increase in UV-to-dark current ratio from 284 to 488 at 10 V respectively.