COIL-TO-SAMPLE DISTANCE INFLUENCE ON CONTACTLESS QSSPC EFFECTIVE LIFETIME MEASUREMENTS: APPLICATION TO SILICON WAFERS PASSIVATED WITH THIN AMORPHOUS SILICON LAYERS

摘要

The quasi-steady-state photoconductance (QSSPC) technique is well established in both research andindustry for the study of crystalline silicon (c-Si) wafers passivated by thin-films for photovoltaic applications. Othermethods to passivate c-Si wafers, involving liquids such as HF or iodine-methanol have also been reported. In thiscase the QSSPC setup needs a re-calibration to avoid effect of the containers’ thickness on the measuredphotoconductance. In this paper, the dependence of the QSSPC output values on the distance between the sample andthe stage (lift-off) is studied through both analytical simulation and experimental results. We provide a simplecorrection law in order to retrieve the true effective lifetime with no need to change the factory calibration.