Growth mechanism and defect structures in epitaxial silicon

Abstract

Abstract Thin layers of silicon have been grown epitaxially on silicon substrates by hydrogen reduction of trichlorosilane. The initial mode of growth of these films has been studied using electron microscopic methods to examine substrates and surfaces exposed to slow growth rate conditions for short periods. These observations have been supplemented by glancing angle electron diffraction studies of the same surfaces, and have shown that growth commences by a three-dimensional nucleation process, probably as a result of slight residual surface contamination. Chemical etching of grown surfaces has revealed that defect structures are present in the epitaxial layers. The nature and origin of these defects have been investigated by transmission electron microscopy and electron diffraction.