An investigation of the defects that form near oxide-filled trenches during solid-phase epitaxy of amorphous silicon produced by ion implantation was conducted. It was observed that defects form near the trench edge after recrystallization. Defect formation resulted from pinning of the initial amorphous/crystalline interface at the trench edge and regrowth proceeded until triangular amorphous regions bound by the surface, trench, and (111) plane were formed. Regrowth of the triangular regions then proceeded along the [111] direction and was highly defective after recrystallization. Annealing of specimens with oxide-free trenches produced smaller defective regions compared to oxide-filled trenches. (c) 2007 The Electrochemical Society.