溅射二氧化铈氧敏薄膜的XPS研究

XPS Studies of New Oxygen Sensing Thin Films Made by Sputtered Cerium Dioxide

本文用射频磁控溅射法制备了CeO2-x高温氧敏薄膜。利用X射线光电子能谱（XPS）研究了不同处理条件对CeO2-x薄膜电子组态的影响，特别是对表面的价态和吸附性质的影响。通过对Ce3dXPS谱的高斯拟合，计算了Ce3+浓度并给出了判定Ce4+还原的标志。研究结果表明，在空气中经1173K高温退火后可得到结晶完好的多晶CeO2薄膜，而薄膜的化学价态没有变化，退火前后薄膜表面总有少量Ce3+存在（15％）。退火后部分还原的CeO2表面具有极强的吸附和再氧化能力，还原程度越高，其再氧化的能力也越强。

The CeO2-x films were deposited from a sintered CeO2-x. ceramic target by reactive high frequencysputtering magnetron system. X-ray photoelectron spectroscopy of Ce3d core level was fit by Gaussion lineshapes forcalculating the different conentration of Ce3+ in the films. Influence of annealing processes and different treating conditions on the composition and structure, especially on the valence of cation and adsorption of CeO2-x films were determined by XPS. The results showed that there were always a small amount of Ce3+ in the films and their concentrationdid not changed before and after annealing process. Partially reduction films after annealing in air were most favorableto adsorption and reoxidation. The heavier extent of reduction was, the more powerful reoxidation was.