Temperature-programmed-desorption study of the process of atomic deuterium adsorption onto Si(100)2×1

The process of atomic deuterium adsorption onto Si(100)2×1 surfaces was investigated by the temperature-programmed-desorption (TPD) method, whose spectrum was successfully decomposed into contributions from mono- and dihydride phases. The time evolutions of these phases were described quite well with a model that involves an initial formation of the monohydride phase from surface bare Si atoms, followed by a delayed development of the dihydride phase. Although their qualitative behavior agreed with kinematical considerations, quantitative analysis indicates a difference in the dynamical factors in these processes. The observed saturated surface coverage (1.56 ±0.18 ML) below 2 ML was also interpreted as being determined by a balance of mutual conversions between monohydride and dihydride phases.