| Přispěvatelé: |
Brendel, Rolf, Ballif, Christophe, Dubois, Sebastien, Glunz, Stefan, Hahn, Giso, Poortmans, Jef, Verlinden, Pierre, Weeber, Arthur |
| Zdroj: |
De Guzman, J A T, Markevich, V P, Mullins, J, Grant, N, Murphy, J D, Hiller, D, Halsall, M P & Peaker, A R 2022, Formation and Elimination of Electrically Active Thermally-Induced Defects in Float-Zone-Grown Silicon Crystals . in R Brendel, C Ballif, S Dubois, S Glunz, G Hahn, J Poortmans, P Verlinden & A Weeber (eds), SiliconPV 2021-11th International Conference on Crystalline Silicon Photovoltaics ., 130003, AIP Conference Proceedings, vol. 2487, American Institute of Physics, 11th International Conference on Crystalline Silicon Photovoltaics, SiliconPV 2021, Hamelin, Virtual, Germany, 19/04/21 . https://doi.org/10.1063/5.0089287 |
| Popis: |
Understanding the origins of the phenomena that limit the minority carrier lifetime in float-zone-grown silicon (FZ-Si) is an important area in photovoltaics research. Although FZ silicon has been applauded for its stability, purity, and high minority carrier lifetime, it has been found recently that severe degradation of the minority carrier lifetime occurs in FZ-Si crystals upon thermal treatments in the temperature range 400-700 °C and upon light soaking at elevated (~100 °C) temperatures. In this work, deep level transient spectroscopy (DLTS) and high-resolution Laplace DLTS have been used to elucidate the formation and elimination processes of the electrically active thermally-induced defects. Float-zone-grown n-type Si crystals with and without added nitrogen from different suppliers have been studied. It has been found that the spectra of deep levels from thermally-induced defects are different in FZ-Si crystals from different manufacturers. Significant qualitative changes were observed in the DLTS spectra after heat-treatments of the FZ-Si samples at different temperatures for different treatment duration. These results indicate various defect reactions occurring upon heat-treatments in FZ-Si materials with varying ensembles of intrinsic defects, doping, and residual impurities in the as-grown state. Also, we have found that hydrogenation from a remote plasma source with subsequent low-temperature annealing has resulted in the total deactivation of thermally-induced defects in FZ silicon. |
