Stability of the dimer structure formed on Si(100) by ultraclean low-pressure chemical-vapor deposition

Abstract
Stability against air exposure of the dimer structure formed on Si(100) by ultraclean low‐pressure chemical‐vapor deposition was investigated. A 2×1‐reconstructed dimer structure was clearly observed on the epitaxial Si film on Si(100) by reflection high‐energy electron diffraction even after air exposure for 180 min. The dissociation process of the dimer structure and the oxidation process in the air depended on the cooling atmosphere in the reactor after chemical‐vapor deposition as well as on the humidity of the air. It is proposed that the dissociation of the dimer structure in the air is suppressed by hydrogen adsorption and coincides with the oxidation of H‐terminated or dangling bonds due to H2O adsorption.