High quality surface passivation is of growing importance in the field of photovoltaics because of the continuous improvement of wafer quality. Modulated Photoluminescence (MPL) is a powerful tool that allows to measure the minority carrier lifetime [1] of semiconductors. An in-house PECVD reactor with in-situ MPL tool [2] is used to study the evolution of passivating properties during annealing. The measured MPL signal was post-treated in order to take into account two important features. The lifetime calculated from phase shift of the MPL signal is a differential lifetime, from which can be extracted the effective [3]. It also varies with temperature despite the absence of changes in passivation. This dependence is modelled by a power law [4], so that in the following graph, the equivalent lifetime at 300K is plotted, in order to narrow down observations to changes in passivation properties.
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