Ti/Al_2O_3界面的光电子能谱研究

用X射线光电子谱（XPS）和俄歇电子能谱（AES）研究了Ti／Al_2O_3界面形成的过程。研究表明，活性金属Ti在室温下能与衬底Al2O3（1102）形成约20nm强结合的界面区。从Al，O，Ti的光电子谱形状变化以及它们随着Ti覆盖度的增加而出现结合能位移表明，在界面处形成的反应层中，最初几个单层的Ti很容易被Al2O3表面的活性氧所氧化，从而使Ti／Al2O3界面逐步由具有更强相互作用的TiOx／Al2O3界面所代替，并形成由多相混合体［Ti-O相，（Ti，Al）2O3相以及金属Al相］所组成的界面区。就是说，Ti通过Al—O键的O2-离子转移其电子给Al3 并使它还原成金属Al，从而形成Ti－O键所致。本文用AES强度剖面分析观察到了这种被还原的Al。

STUDY OF THE Ti/Al_2O_3 INTERFACE BY XPS AND AES

The formation process of Ti/Al2O3(1102) interface has been studied by X-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy(AES). The results showed that the active metal titanium formed a strong interface region of 20nm with the Al2O3(1102) substrate at room temperature.The shape-change of the photoelectron spectra of Al,O and Ti, and the shift of the binding energy with increasing the coverage of Ti showed that at the interface,in the first several monolayers of Ti,titanium was oxidized due to the active oxygen anions on the surface. Therefore,the Ti/Al2O3 interface was replaced gradually by TiOx/Al2O3 interface,which has stronger interaction than the former. Reaction layer which consists of multiphase mixture:the Ti-O type phase,the (Ti,Al)2O3 phase and the reduced metallic aluminium phase. It is due to that Ti transferred its electrons to Al3 via O2- anions in the Al-O bond,and formed Ti -O bond,thereby the Al3 was reduced to metal aluminium. Our AES intensity profile proved the existence of the reduced species Al.