New insights into the thermally activated defects in n-type float-zone silicon

Abstract

Float-zone silicon has been long assumed to be bulk defect free and stable. Nevertheless, recently it was found that upon annealing between 450 °C to 700 °C detrimental defects can be activated in this material. Previous studies via deep level transient spectroscopy have identified several defect levels. However, it is still not clear which of these levels have a substantial impact on the minority carrier lifetime. In this study, we determine the recombination parameters of the dominant defect level using a combination of deep level transient spectroscopy and temperature and injection dependent lifetime spectroscopy. Additionally, we investigated the effect of hydrogenation on the thermally activated defects in ntype float-zone silicon.