The origin of minority carrier trapping centres in multicrystalline material was studied in gettered and non-gettered samples. The results suggested that there were 2 types of trap present. One species could be removed by gettering, and was related to the presence of B-impurity pairs or complexes. The other type was impervious to gettering and was related to the dislocation density. Annealing experiments revealed that the trapping centres which were caused by B-impurity complexes could be dissociated, and that these trapping centres did not contribute to recombination.

Understanding Carrier Trapping in Multicrystalline Silicon. D.MacDonald, A.Cuevas: Solar Energy Materials and Solar Cells, 2001, 65[1-4], 509-16