Effects of Arsenic Doping on the Solidification Dynamics of Pulsed Laser Melted Silicon

摘要

The effects of arsenic doping on the solidification dynamics during pulsed melting of silicon have been studied using the transient conductance technique. At As concentrations below 1 at. %, the incorporation of As into the Si lattice results in negligible differences in the solidification dynamics. Between 2 and 7 at. % As, however, the interface velocity is dramatically modified as the liquid-solid interface crosses the As containing region. These velocity changes are consistent with a reduced melting temperature for Si-As alloys. For concentrations of 11 at. % As, the depression in the melting temperature is sufficient to allow the surface to solidify while considerable melt remains buried within the sample. At 16 at. %, the melting temperature is drastically reduced and internal nucleation of melt occurs prior to normal surface melting. 11 refs., 4 figs. (ERA citation 10:051858)