Phase Transitions in Amorphous Si Produced by Rapid Heating

Abstract

Amorphous Si layers have been melted by pulsed electron irradiation. Implanted As has been used as a marker for determining melt duration. Systematic differences between As diffusion in initially amorphous or crystalline Si are interpreted in terms of different enthalpies of melting between amorphous (1220 J/g) and crystalline (1790 J/g) Si. The implanted amorphous layers melt and crystallize at significantly lower electron energies than those required to melt and recrystallize crystalline Si, indicating that amorphous Si melts at 1170 K compared to 1685 K for crystalline Si.