Characterization of epitaxial and oxidation-induced stacking faults in silicon: The influence of transition-metal contamination

Abstract

Photoluminescence (PL) spectroscopy, transmission electron microscopy (TEM), and defect etching have been used to characterize epitaxial stacking faults (ESF) in silicon epilayers grown by low-pressure chemical vapor deposition (LPCVD) and oxidation-induced stacking faults (OISF) in high-purity float-zone (FZ) Si. No dislocation-related luminescence was observed from either ESFs or OISFs grown under clean conditions. Deliberate surface contamination, followed by annealing with Cu, Fe, Ni, Ag, or Au in the range 4×1012–2×1016 atoms cm−2 introduced dislocation luminescence features, with a maximum intensity at ≊4×1012 atoms cm−2. TEM examination revealed that there was no evidence for precipitation at low levels of contamination but as the contamination level increased metal-related precipitates were observed on the bounding partial dislocations.