Interface analysis of HfO2 films on 100 Si using x ray photoelectron spectroscopy

Thin layers of HfO2 grown on the 1 amp; 8201;0 amp; 8201;0 Si crystal surface using atomic layer deposition or metallo organic chemical vapour deposition were analysed using x ray photoelectron spectroscopy XPS of Hf 4f, Si 2p and O 1s electron states. The chemical indepth profiling was conducted by combining XPS with Ar ion sputtering. In addition to establishing the deposition sensitive oxide structure, Ar ion sputtering was found to lead to the formation of a metallic Hf layer on the surface of the sample. The latter observation suggests HfO2 as a feasible candidate for not only insulating applications but, thanks to the high mass and electron density of the cation, also as a material suitable for the fabrication of nanometre sized conductors by direct oxide decompositio