Molecular Dynamics Simulation of the Interactions of H Radicals with a Hydrogenated Si(001) Surface

Abstract

In order to analyze the effects of the surface H atoms on elementary surface reactions, we repeated molecular dynamics simulations in which an H radical fell onto a hydrogen-terminated Si(001) surface. As a result of the simulation, we found that high hydrogen coverage inhibits H radicals from being adsorbed within the silicon substrate. Hydrogen radicals mainly caused adsorption or the H abstraction reaction, which generated several kinds of local surface structures with dangling bonds, and it was suggested that various local surface structures coexist on a growing surface. The local surface structure significantly affected the result, and its reactivity was high when the structure had a dangling bond, although a small difference in results was observed depending on the surrounding structures. These results indicate that the change in the local surface structure caused by H radicals may induce subsequent surface reactions.