AES and EELS study of aluminium oxide thin films

Amorphous aluminium oxide films were prepared by vapor deposition using a special molybdenum evaporation cell heated by electron bombardment. The Al/O stoichiometry of layers was controlled in situ by Auger Electron Spectroscopy (AES) and by Electron Energy Loss Spectroscopy (EELS) that permitted to monitor the increase of Al/AlOx Auger intensity ratio and the presence of metallic aluminium in the deposit (Al degrees rich layer) via an excitation of Al plasmon. We investigated the surface stoichiometry by comparing the AES and EELS spectra of deposited layers with the bulk alpha-alumina and oxidized aluminium. It has been demonstrated that the vapor deposition method gave good quality layers without their contamination by crucible material. (C) 1998 Elsevier Science S.A.