Theoretical and Experimental Optical Spectroscopy Study of Hydrogen Adsorption at Si(111)-(7×7)

Abstract

The combination of in situ real-time surface differential reflectivity (SDR) spectroscopy and microscopic calculations has been used for the first time to investigate gas adsorption on a Si surface. The optical signatures of some microscopic structural units of Si(111)-( $7\times 7$) have been identified. The development of the corresponding features in the SDR spectra upon the amount of H exposure allowed us to demonstrate the occurrence of two different mechanisms in the hydrogenation and to determine their relative kinetics.