STRESS-INDUCED FORMATION OF STRUCTURAL DEFECTS ON THE (311) PLANES OFSILICON

Structural defects occurring on the {311} planes of single crystal sil icon have been observed near the bottom oxide corner in silicon-on-ins ulator structures formed by selective epitaxial growth. These {311} de fects exhibit a preferential orientation and are clustered near the si licon/silicon dioxide interface. This new observation provides an oppo rtunity to study the mechanism of {311} defect generation in a system with discernible microstructure and stress state. High resolution elec tron microscopy combined with analytical and numerical three-dimension al stress modeling are used to show the dependence of these {311} defe cts on the local stress field, and to establish their origin in terms of a homogeneous dislocation nucleation model.