A study of so-called oxide-induced stacking fault rings was carried out by using 2 independent techniques. The minority-carrier lifetime was mapped by using the laser microwave photoconductivity decay method, and was correlated with transmission X-ray topographic images of the wafer. Additional features of the lateral and depth-dependent stacking fault densities were revealed by preferential etching. It was found that the minority-carrier lifetime within the annular oxide-induced stacking fault ring itself was about an order of magnitude lower than that outside the ring. An intermediate lifetime was observed within the ring. Temperature-dependent laser microwave photoconductivity decay data revealed that redistribution of Fe impurity occurred via gettering by the stacking faults. This was confirmed by deep-level transient spectroscopic data.

J.Raebiger, A.Romanowski, Q.Zhang, G.Rozgonyi: Applied Physics Letters, 1996, 69[20], 3037-8