Ion beam induced epitaxy experiments in silicon under channeling and random alignments

This paper examines issues arising in ion beam induced epitaxial crystallis ation (IBIEC) of both surface and buried amorphous silicon layers at 320 de grees C under random and channeled alignment of MeV C+ beams. These issues include: random versus channeled energy loss, multiple scattering in amorph ous layers, direct displacement versus cascade effects on IBIEC and Rutherf ord backscattering depth scales. Multiple scattering within amorphous layer s and channeled energy loss for MeV He+ and C+ beams were directly measured using Rutherford backscattering/channeling (RBS-C) and markers. When the a bove issues were taken into account the IBIEC measurements indicated that e pitaxial growth is stimulated by silicon displacements very close to the am orphous-crystalline interface. However, effects in buried amorphous layers show that displacements at the interface due to cascades rather than primar y ion displacements play a major role in determining random versus channele d behaviour. (C) 2000 Elsevier Science B.V. All rights reserved.