Simplified method for the conversion of luminescence signals from silicon wafers and solar cells into implied voltages

Electroluminescence and photoluminescence imaging of crystalline silicon solar cells are powerful characterization techniques for research and industrial applications. Both techniques can provide spatially resolved data of the implied open-circuit voltage, a critical parameter for photovoltaic devices. However, the conversion of luminescence intensities into implied voltages often requires a challenging calibration process, which must be performed separately for distinct sample types. Here, we present a novel voltage calibration method for silicon wafers and cells, which eliminates the need for sample-specific calibration. We demonstrate that with a suitable selection of optical filters, the error in the implied open-circuit voltage for typical textured silicon solar cells and wafers can be limited to 3 mV.