Observation of hydrogen adsorption on Si 001/ by reflectance difference spectroscopy

The kinetics of hydrogen adsorption on Si 001.has been studied by reflectance difference spectroscopy RDS.. We measured the hydrogen coverage on Si 001.estimated from the peak intensity of RDS, which is sensitive to hydrogen termination of the dangling bonds of silicon dimers. A detailed study of the adsorption kinetics showed that atomic hydrogen adsorbed on Si 001.with a ‘hot precursor’ mechanism, in which the adsorbed hydrogen can roam across the surface in search of an unoccupied dangling bond to terminate. In the hydrogen termination, the peaks of RDS changed in different ways. This indicates that the peaks have different origins. q1998 Elsevier Science B.V. All rights reserved