Real Time Investigation Of The Growth Of Silicon Carbide Nanocrystals On Si(1 0 0) Using Synchrotron X-ray Diffraction

摘要

The growth of silicon carbide nanocrystals on Si(1 0 0) is studied by synchrotron surface X-ray diffraction (SXRD) during annealing at high temperature. A chemisorbed methanol monolayer is used as carbon source, allowing to have a fixed amount of carbon atoms to feed the growth. At room temperature, minor changes in the 2 × 1 reconstruction of silicon are observed due to the formation of Si-O-CH_3 and Si-H bonds from methanol molecules. When annealed at 500 ℃, carbon incorporation into the silicon leads only to local modifications of the surface structure. Above 600 ℃, tri-dimensional silicon carbide nanocrystals growth takes place, together with surface roughening and sharp decrease of domain sizes of the 2 × 1 reconstruction. The different processes taking place at each temperature are clearly distinguished and identified during the real time SXRD measurements.