Title :
Comparison of spatially resolved carrier lifetimes in mc-Si with solar cell and material characteristics
Author :
Glunz, S.W. ; Hebling, Ch ; Warta, W. ; Wettling, W.
Author_Institution :
Fraunhofer-Inst. fur Solare Energiesysteme, Freiburg, Germany
Abstract :
We introduce a novel application of modulated free carrier absorption (MFCA) for measuring minority carrier lifetimes in multicrystalline silicon with high spatial resolution. The improved lateral resolution compared to other contactless techniques allows the correlation between these lifetime maps and solar cell characteristics as well as microscopic properties, like dislocations, precipitates, oxygen concentration, etc. Comparisons of the lifetime maps measured on the starting material and light beam induced current (LBIC) maps exhibit a very good qualitative correlation of the structures observed in both cases. In addition, correlations to microscopic characteristics like high dislocation density in regions with low lifetimes are investigated and a comparison with spatially resolved FT-IR measurements of the interstitial oxygen concentration is performed
Keywords :
Fourier transform spectroscopy; OBIC; carrier lifetime; dislocation density; elemental semiconductors; infrared spectroscopy; minority carriers; semiconductor materials; silicon; solar cells; Si; contactless techniques; dislocations; high dislocation density; high spatial resolution; interstitial oxygen concentration; lateral resolution; material characteristics; microscopic properties; minority carrier lifetimes measurement; multicrystalline silicon; oxygen concentration; precipitates; solar cell characteristics; spatially resolved FT-IR measurements; spatially resolved carrier lifetimes; Absorption; Charge carrier lifetime; Crystalline materials; Current measurement; Density measurement; Microscopy; Optical modulation; Photovoltaic cells; Silicon; Spatial resolution;
Conference_Titel :
Photovoltaic Energy Conversion, 1994., Conference Record of the Twenty Fourth. IEEE Photovoltaic Specialists Conference - 1994, 1994 IEEE First World Conference on
Conference_Location :
Waikoloa, HI
Print_ISBN :
0-7803-1460-3
DOI :
10.1109/WCPEC.1994.520528
