SEM and AES depth profile studies of thin titanium and titanium oxide films covered by nanoscale evaporated Au layers

Thin titanium and titanium oxide films, both covered by ultra-thin gold layers, have been compared with titanium films after analysis, using a combination of SEM and AES. The Ti films were prepared under UHV conditions by evaporation on a glass substrate. The Ti oxide layers were prepared in situ by precisely controlled oxygen sorption at 298 K on Ti film. Both Ti and Ti oxide films were then covered in situ by a very thin Au layer. Analysis was performed in a separate system after long-term exposure of the films to air. SEM analysis revealed a much smaller size grain on the Au coated Ti films than on Ti films not coated with a Au layer. The thin gold layers covering the Ti surface prevent an extensive air interaction with Ti film. The analysis of the features of the Ti Auger spectra during the sputter profile measurements allow to characterise the chemical nature of Ti-oxide formed in Ti/Au interface region. Received: 7 September 1998 / Revised: 14 January 1999 / Accepted: 2 February 1999