The impact of oxygen on Ga doped ZnO film
Yufeng Zhang, Wenxiong Zhao, Qiuchen Wu, Xinlu Lin, Ziyao Zhu, Ruchun Li, Yuhang Liu, Kai Huang, Xiangxin Liu
Abstract
appeared and disappeared in GZO films during the increase of oxygen partial pressures. Analogously, conductivity decayed and optical bandgap decreased abruptly as oxygen was introduced, which enhanced self-compensation of donors and acceptors. The energy band structures of GZO and ZnO films were determined by using UPS, and the results showed that oxygen had little effect on the electron affinity of the GZO film, but a significant difference in electron affinity between the ZnO and GZO films was observed. This result indicated that although the electron affinity of ZnO could be effectively tuned by doping with Ga, it remained quite stable for GZO under oxygen-rich conditions.