Pulsed Laser-Induced Amorphization of Polycrystalline Silicon Film

Abstract
A 20 nm-thick polycrystalline silicon film was completely amorphized through laser-induced melt-regrowth using a 30 ns XeCl excimer laser pulse at an energy density of over 240 mJ/cm2. Moreover, the amorphized silicon was recrystallized by irradiation by a single pulse at an energy density below 240 mJ/cm2. The transition from the amorphous to the crystalline state was reversible and governed by the laser energy density. The laser-induced amorphized film had a low optical band gap of 1.4 eV. Its electrical conductivity was characterized by variable-range hopping.