Absolute Characterization of Solar Cells by Electroluminescence Imaging

In this work [1], we derived a new method to map several optoelectronic parameters of solar cells from voltage dependent electroluminescence imaging. We introduce a calibration factor generally left unknown in the literature. Example is shown on Al-BSF silicon solar cell for which we map the following parameters: diffusion lengths, dopant concentration, dark saturation current, local voltages and lumped series resistances. Comparison with other electroluminescence imaging methods is also shown. Preliminary knowledge about the sample are the spectral reflection coefficient, average dopant concentration and back surface recombination. This method can also be derived for other kind of solar cell cells by using appropriate carrier collection model depending on their structure