Effects of As impurities on the solidification velocity of Si during pulsed laser annealing

The effect of As dopants on the solidification velocity during pulsed laser annealing of Si was measured using the transient conductance technique. At high concentrations, As is found to decrease the solidification velocity; for 7 at. % As, the velocity decreases ∼20% as the interface approaches the peak of the As distribution, followed by a velocity increase when the interface exits the region of maximum As concentration. The measurements are interpreted in terms of a decrease in the melting temperature. The observation of surface nucleation to produce buried molten layers and internal nucleation of melt at higher As concentrations supports this interpretation.