Faceted Melting and Superheating of Crystalline Si Irradiated with Incoherent Light

Abstract

ABSTRACTWe report and analyze the breakup of a crystalline silicon surface into solid and molten faceted segments by radiative heating. Melting starts at discrete sites since there is a nucleation barrier requiring superheating of the surface. Once started, the melt remains localized and does not encompass the entire surface because of the changes in optical properties of Si upon melting. It is estimated that superheating by <0.5 K should be sufficient to stabilize faceted melt regions spaced 200 μm apart. The preliminary measurements, however, indicate superheating by several degrees.