Modeling the phase-change processes in pulsed laser-irradiated InSb

Both theoretical and experimental analyses of pulsed laser-induced phase-ch ange processes in the near surface region of monocrystalline bulk InSb are treated in the paper. In the theoretical part, thermal equilibrium and none quilibrium models of melting, recrystallization, and evaporation are formul ated to describe transport phenomena in the material induced by laser irrad iation. In the experimental part, (110) and (111) InSb samples irradiated b y ruby [694nm, 80 ns full width at half maximum (FWHM)], and ArF (193 nm, 1 0 ns FWHM) lasers were studied. Time-resolved reflectivity measurements wer e performed in order to determine the melting thresholds and surface-melt d urations. Auger electron spectroscopy and low-energy electron diffraction m ethods were employed to monitor surface modifications. A combination of exp erimental measurements and computer simulations reveals that, while for rub y laser the material remains crystalline after irradiation, for ArF laser t he InSb sample is amorphized; the amorphization threshold is estimated to b e similar to 4-5 m/s. The decomposition of InSb at temperatures close to it s melting point was also observed, the decomposition temperature being esti mated within the range 900-950 K. [S0163-1829(99)09915-4].