Er_2O_3/Si外延薄膜表面和界面组分研究

Surface and Interface of Er_2O_3 Films Epitaxially Grown on Si Substrate:An X-Ray Photoelectron Spectroscopy Study

利用X射线光电子能谱方法对Si基Er2O3外延薄膜的化学组分进行了分析。在X射线照射样品和氩离子轰击使样品减薄的过程中没有诱发其他的化学反应。研究了清洁的Si和有氧化层的Si衬底上外延生长的Er2O3薄膜的表面和界面化学组分情况,并对上述两种不同的衬底上外延生长Er2O3薄膜的生长模式进行初步探讨。

The Er2O3 films were grown by molecular beam expitaxy （MBE） on p-type Si（001） and Si（111） sub- strates. The microstructures and stoichiometries of the films, before and after cleaning with argon ion sputtering, were characterized with x-ray photoelectron spectroscopy （XPS）. No chemical reaction induced by X-ray irradiation or by Ar ion sputtering was observed. The preliminary results show that the silicon oxide coverage on Si substrates strongly affects the stoiehiometries of the Er2O3 films. For instance, a SiOx layer was found to be on top of the Er2O3 films grown on oxidized Si（001） substrate;in contrast, no such SiOx layer exists on Er2O3 films grown on clean Si substrates. Possible mechanisms were also tentatively discussed.