エピタキシャル成長の化学反応

Abstract

The vapor phase silicon epitaxial reaction is taken as an example of chemical reactions in the crystal growth.As growth rates are mainly controlled by gas phase mass transfer, it is particularly shown that gas concentrations near the crystal surface are affected by surface processes and thermal diffusion. Futhermore, theoretical chemical equillibrium data including the calculation method and experimental gas concentration distributions of multicomponent species are cited from references.At low pressure epitaxy the main species is simply SiCl2 of the chemical condensation type. In this case, there is the metastable region on the supersaturation diagram where homoepitaxy proceeds preferentially than hetro-epitaxy.Finally, substrate orientation effects on growth rates are illustrated from the surface kinetics.