Firing and gettering dependence of effective defect density in material exhibiting LeTID

The investigation of LeTID effects in mc-Si material requires repeated measurements of the minority charge carrier lifetime τeff. Due to the inhomogeneous nature of mc-Si, measurements of τeff should be carried out in a spatially resolved way. In this work, we show results for the impact of firing and gettering on LeTID in high quality mc-Si material and analyse them in terms of the effective defect density Neff while retaining the spatial information. We show that especially for low peak firing temperature degradation is not homogeneous and that firing and gettering influence the degree of spatial inhomogeneity.The investigation of LeTID effects in mc-Si material requires repeated measurements of the minority charge carrier lifetime τeff. Due to the inhomogeneous nature of mc-Si, measurements of τeff should be carried out in a spatially resolved way. In this work, we show results for the impact of firing and gettering on LeTID in high quality mc-Si material and analyse them in terms of the effective defect density Neff while retaining the spatial information. We show that especially for low peak firing temperature degradation is not homogeneous and that firing and gettering influence the degree of spatial inhomogeneity.