Publication at Faculty of Mathematics and Physics |
2009
Abstract
STM and PES study of the Ta/Si(111)-7x7 system after deposition of 0.05-2 ML Ta at substrate temperatures from 300 to 1250 K is presented. STM shows that at 300 K and coverage less than 1 ML, a disordered chemisorbed phase is formed.
Deposition on a hot surface (above 500 K) produces round 3D clusters randomly distributed on the surface. Analysis of photoemission data of the Si 2p core levels shows that at room temperature and at coverage {=1 ML core level binding energy shifts are observed, which clearly indicate that the reaction starts already at 300 K.
Changes of the peak shapes of the Ta 4f doublet at higher temperatures can be explained by the formation of stable silicide on the surface.