KINETICS, MICROSTRUCTURE AND MECHANISMS OF ION BEAM INDUCED EPITAXIAL CRYSTALLIZATION OF SEMICONDUCTORS.

Abstract

Ion-beam induced epitaxy is shown to be essentially athermal over the temperature range 200-400 degree C, and to exhibit no dependence on substrate orientation and little dependence on doping in this regime. On the other hand, the formation and propagation of defects during growth and the interaction of the advancing crystal-amorphous interface with implanted impurities is essentially identical for both thermally induced and ion-beam induced epitaxy. These observations lead to a simple model for ion-beam induced epitaxial crystallization in which epitaxial growth is nucleated by defects generated at, or near, the crystal-amorphous interface by the ion beam. Comparisons of ion-beam induced epitaxy and thermally induced epitaxy suggest that the 2. 7 eV activation energy associated with the latter process is dominated by a 2. 0 eV nucleation step.