Explosive Recrystallization Of Ion Implantation Amorphous Silicon Layers

Abstract

ABSTRACTExplosive recrystallization of amorphous layers, induced by scanned electron or CW Ar+ laser beams, has been investigated in arsenic implanted (100) specimens. We have studied the microstructural changes using plan-view and crosssection electron microscopy to obtain the mechanism of explosive recrystallization phenomenon. The confinement of heat in the amorphous layers during laser irradiation and the nature of amorphous silicon determine the modes of explosive recrystallization. We indicate that, depending upon the degree of undercooling, two distinct modes of liquid-phase recrystallization are observed: one occurring at a velocity of, ∼2 ms−1 and the other at ∼10ms−1. Explosively recrystallized grains contain <110> and <110> as surface normal and growth direction respectively. We present a model for unseeded crystallization to explain the <110> texture observed in diamond cubic lattices.