X-RAY PHOTOELECTRON-SPECTROSCOPY DEPTH PROFILING OF ALUMINUM NITRIDE THIN-FILMS

Aluminium nitride thin films grown at room temperature on degenerate s ilicon (conducting) substrates have been studied using XPS. The hydrol ysis layer at the surface of the AlN was examined using valence band m easurements, and the effect of 5 kV argon ion milling used to remove t he hydrolysis layer was scrutinized using angle-resolved XPS. The N/Al ratios found from the angle-resolved measurements indicate nitrogen d epletion from the surface of the milled samples, whereas O/Al ratios i ndicate no such depletion of oxygen, After argon ion milling, carbon u ptake from the ultrahigh vacuum analysis chamber was found to be signi ficant. (C) 1997 by John Wiley & Sons, Ltd.