Ab initio derived kinetic Monte Carlo model ofsdesorption from Si(100)-2×1

Using an ab initio derived kinetic Monte Carlo model, we show that within the framework of a mechanism involving the systematic conversion of monohydrides to dihydrides and the prepairing assumption, (Formula presented) desorption from Si(100)-2×1 via isolated dihydrides follows first-order kinetics. Our model predicts that the kinetic order is invariant with respect to coverage, temperature, and surface features (e.g., steps and defects). However, we show that the concentration of defects on the surface has a profound effect on the desorption rate constant. The dependence of the rate constant on surface quality might explain the wide range of experimental values reported for the desorption rate constant.