Surface solidification and impurity segregation in amorphous silicon

Abstract
Real-time measurements of the melt and solidification dynamics during pulsed laser irradiation have permitted elucidation of the processes which lead to the formation of very thin (∼2 nm) buried impurity layers in amorphous silicon. These novel structures are found to result from interfacial segregation at two moving liquid silicon-amorphous silicon interfaces—one propagating toward the surface and the other propagating from the surface inward. The velocities of these interfaces are found to be remarkably low, ranging from 1 to 8 m/s for melts of <20 ns duration.
Keywords