Pulsed Laser-Induced Crystallization and Amorphization of SiGe Films.

Abstract

ABSTRACTPulsed laser-induced melting followed by crystallization and amorphization were studied on silicon-germanium alloy (SiGe) films. Although amorphization was achieved on SiGe films, it was not observed in pure Ge films. Crystalline nucleation density in homogeneous solidification increased as Ge concentration increased. It was 1×1024m-3for Si0.22Ge0.78 films, while it was 4×1022m-3 for pUre si films. Electrical conductivity of laser polycrystallized films increased as Ge concentration increased. It had a maximum of 1 S/cm when Ge concentration was 0.78. This high electrical conductivity would be brought about by the increase of carrier mobility as well as the reduction of the band gap.