Auger studies of chemical bonds and oxygen minimization in the interfaces between AlN and SiC thin films deposited by LPCVD

Abstract

In order to obtain a minimization of the oxygen concentration in the interface region between an AlN film and an SiC film, the two films were deposited successively in the same CVD reactor by changing the temperature and the nature of the gaseous precursors. Two continuous processes of successive depositions were tested. The Auger depth profiles analyses showed large depth interfaces (between 50 and 90 nm), without the usual increase in oxygen concentration generally found into the interface if the substrate is contaminated by atmosphere. Al-N, Si-C and presumably Si-N bonds were detected in the two AlN/SiC interfaces investigated in this work. C-N bonds were detected in the AlN/SiC interface after treatment of the SiC film surface by NH 3 before the deposition of AlN using NH 3 and AlCl 3 precursors.