Au and Au3 ions in CeO2 rf-sputtered thin films

作者：Matolin V^*; Cabala M; Matolinova I; Skoda M; Libra J; Vaclavu M; Prince K C; Skala T; Yoshikawa H; Yamashita Y; Ueda S; Kobayashi K

来源：Journal of Physics D: Applied Physics , 2009, 42(11): 115301.

DOI：10.1088/0022-3727/42/11/115301

The interaction of gold with CeO2 layers was investigated using photoelectron spectroscopy. 65 nm thick Au doped CeO2 layers were deposited by rf-magnetron sputtering on a Si(001) substrate by using a composite CeO2-Au target. The laboratory XPS and synchrotron radiation soft x-ray and hard x-ray photoemission spectra showed the formation of stoichiometric Ce4+ (CeO2) and the appearance of new Au-+,Au-3+ states with ionized Au species in excess of 50% of the total Au amount. Depth resolved measurements, by varying the emission angle or photon energy, indicated the formation of an Au-0 overlayer and deeper Au-+,Au-3+ species. The formation of Au-+,Au-3+ ions was found to be strongly dependent on the cerium oxide stoichiometry. The amount of ionized Au can be reversibly decreased and increased by surface reduction (removal of O by sputtering) and subsequent surface re-oxidation.

• 出版日期2009-6-7