Options
2009
Conference Paper
Titel
Impact of SiNx:H and Al2O3 surface passivation on interstitial iron concentration and carrier lifetime in mc-silicon wafers
Abstract
In this study we investigate and compare the influence of two different surface passivation methods on the bulk properties. As passivation layers the widely used PECVD-SiNx:H and the recently developed Al2O3 passivation layer, deposited by atomic layer deposition (ALD), are investigated. Changes in the carrier lifetime due to the applied temperature (and additionally hydrogen-passivation in the case of SiN) were assessed and special interest was paid to the interstitial iron (Fei) concentration. We could show that H-passivation, coming from the hydrogen rich SiN layer, rises lifetimes, but does not alter the Fei concentration. Nevertheless, a reduction of Fei was observed which is only caused by a temperature-driven precipitation and is not influenced by the H-passivation.