Internal gettering in epi-silicon prepared under different conditions

Abstract

The efficiency of internal gettering in epi-silicon was studied in samples prepared under different conditions as compared to external gettering and p + gettering. The parameters changed were substrate resistivity, oxygen content and presence/absence of poly-Si on the back-side. The efficiency of internal gettering was assessed by measurement of the electron-beam-induced-current contrast versus temperature and applying existing models for interpreting the results. Internal gettering is effective also in p + substrates with poly-Si on the back-side when the density of oxygen precipitates is high and their size small. Internal gettering is not effective for low density of oxygen precipitates when either p + substrates or poly-Si or both are used.