Solid-Phase Epitaxy - Role of Point Defects in Amorphous Solids

Abstract

AbstractA model of solid-phase epitaxial growth (SPEG), explaining enhancing effects of ion-irradiation and dopants, is presented. The crystallization is by the adjustment of atomic positions in the amorphous side of the crystalline/amorphous (c-a) interface due to self-diffusion in the amorphous solid, assisted by a freeenergy decrease associated with the transformation from the amorphous (a) to crystalline (c) phase. Irradiation and electrically active dopants increase the selfdiffusivity of a-phase by generating point defects in the amorphous layer and thus enhance crystallization. An expression for the velocity of epitaxial growth is derived. The low activation energy of ion-induced SPEG is due to recombination of point defects in the a-phase.