Modulated Photoluminescence Lifetime Measurement of Bifacial Solar Cells

The frequency response of photoluminescence (PL) emission in a semiconductor sample is influenced by the effective carrier lifetime. As it is easy to induce and capture PL in solar cells at different stages of processing, modulated PL poses as a versatile technique to track the progression of effective lifetime in silicon wafer solar cells in the production line. This paper demonstrates the application of modulated PL to extract the effective carrier lifetime in n-type silicon bifacial solar cell samples before and after metalization. For nonmetalized samples, good agreement is found in the lifetime curves generated by modulated PL and the more established microwave photoconductance decay technique. For single and double-side metalized samples, the deduced lifetime is also consistent with the implied open-circuit voltage obtained by steady-state PL imaging.