Chlorine Bonding Sites and Bonding Configurations on Si(100)-(2x1).

摘要

A combination of experimental methods has been employed for the study Of C12 adsorption and reaction on Si(100)-(2xl). At 100K, C12 adsorption occurs rapidly to a coverage of -0.7 CI/Si. This is followed by slower adsorption kinetics with further C12 exposure. Two Cl adsorption states are observed experimentally. One of the adsorption states is terminally bonded Cl on the inclined dangling bond of the symmetric Si2 dimer sites, with vibrational frequency, v(SiCI) of 550 - 600 cm-1. These bonded Cl atoms give four off-normal C1+ ESDIAD emission beams from the orthogonal domains of silicon dimer sites. The Si-Cl bond angle for this adsorption configuration is estimated to be inclined 25 deg + or - 4 deg off-normal. The second Cl adsorption state, a minority species, is bridge bonded Cl with v(Si2C1) of - 295 cm-1 which produces Cl+ ion emission along the surface normal direction. Both adsorption states are present at low temperatures.