The feasibility of low temperature processes (below 800°C), to obtain atomically clean and smooth surfaces on (100) oriented silicon on insulator material (SOI) with negligible variation of the top Si film thickness was tested. These processes were characterized by using low-energy electron diffraction (LEED) and atomic force microscopy (AFM) supplemented by conductivity measurements. The evaporation of Si at 750°C at a flux of 0.15 ML/min, the most promising method for obtaining atomically smooth and continuous SOI films was also described. It was shown that at the inner Si/SiO2 interface the formation of volatile SiO was a fast process at temperatures around 1000°C.