采用磁束缚电感耦合等离子体溅射沉积法在不同的氧气分压下制备了Zn0.95Co0.05O和Zn0.94Co0.05Al0.01O薄膜.利用X射线吸收精细结构技术对薄膜O-K,Co-K和Co-L边进行了局域结构研究,结果表明:Co2+取代了四配位晶体场中的Zn2+而未改变ZnO的六方纤锌矿结构,高真空条件下制备的薄膜具有较多的氧空位缺陷.利用共振非弹性X射线散射研究了薄膜Co-L和O-K边电荷转移情况,结果表明:Zn0.94Co0.05Al0.01O薄膜中Co-3d与传导电子之间的电荷转移强度明显强于Zn0.95Co0.05O薄膜,在较低氧气分压下制备的Zn0.95Co0.05O薄膜的电荷转移强度强于高氧气分压下制备的薄膜.
Zn0.95 Co0.05 O and Zn0.94 Co0.05 Al0.01 O films were prepared by inductively coupled plasma enhanced physical vapor deposition with magnetic confinement system under different oxygen partial pressure.The local structure and charge transfer properties were investigated by X-ray absorption fine structure and resonant inelastic scattering spectroscopy at O-K,Co-K and Co-L edges.The Co K-edge and L-edge X-ray absorption fine structure revealed that Co 2+ ions substituted for tetrahedrally coordinated Zn 2+ ions without changing the wurtzite structure.The main defects were oxygen vacancies when the films were deposited under very low oxygen partial pressure.The resonant inelastic scattering spectroscopy indicated that the charge transfer between Co-3d and the electrons in Zn0.94 Co 0.05 Al0.01 O films was much stronger than that in Zn0.95 Co0.05 O.The oxygen partial pressure had an important effect in the charge transfer of Co-doped ZnO films.