Minority carrier lifetime scan maps applied to iron concentration mapping in silicon wafers

Abstract

Mapping of iron concentration is obtained in p-type monocrystalline and multicrystalline silicon by means of contactless lifetime measurements. The recombination rate induced by interstitial iron (Fe i ) and iron boron pairs (FeB), which is very sensitive to injection level, is appreciated thanks to comparison between deep level transient spectroscopy (DLTS) and lifetime measurement by the micro-wave phase-shift technique (μW-PS). Calibration is given for samples doped in the range 5×10 13–3×10 16 cm −3.