Evidence against surface nucleation following pulsed melting of Si

Abstract

Time-dependent measurements of the melt and solidification behavior of amorphous Si, formed by ion implantation of In, have been obtained following irradiation with ∼3 ns ruby laser pulses. The recently observed buried In sheets formed under such conditions are shown to result from internal nucleation of melt, contrary to previous interpretations. Under no conditions was surface nucleation of either amorphous or crystalline Si observed from a surface melt. These results resolve previous inconsistencies in the understanding of phase formation during rapid melting and solidification of Si.