Contactless technique to quantify the edge-junction recombination in solar cells

This letter presents a method to determine the recombination properties of exposed edges of p-n-junction silicon devices, particularly, solar cells. The method is based on the extended analysis of injection level dependent carrier lifetime data of samples with various degrees of intentionally created edges. Its application to laser-cut edges is shown here. Values of per-length space-charge-region recombination current densities of approximately 2×10−8 and 2×10−9A∕cm have been determined for laser-cut- and laser-cut-and-etched edges. The technique is beneficial for both understanding edge recombination in solar cells and developing improved edge passivation techniques.