Light-induced degradation due to BO defects in silicon consists of a fast initial decay within a few seconds followed by a slower decay within hours to days. Determination of injection dependent charge carrier lifetime curves during the initial decay is challenging due to this short timeframe. We have developed a suitable measurement technique based on in situ photoluminescence measurements and present results of our studies of the fast degradation component. The temporal evolution of the recombination activity is studied and assessed by means of a two-level Shockley-Read-Hall statistics. A quadratic dependence of the fast defect activation on the hole concentration during illumination is demonstrated. We suggest a new parameterization of the recombination activity introduced by fast-formed BO defects featuring energy levels 0.34 eV below the conduction band and 0.31 eV above the valence band

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In this study, we present a method to predict the local temperature‐dependent performance of silicon solar cells from wafer lifetime images, which enables local investigation of silicon solar cell parameters under realistic operation conditions. The multicrystalline silicon wafers investigated underwent high‐temperature steps equivalent to emitter diffusion and contact firing for the production of a passivated emitter and rear cell (PERC) solar cell. Injection and temperature‐dependent lifetime images, gathered by calibrated photoluminescence (PL) imaging, are combined with numerical cell device simulations using Quokka3. Hereby, the spatially resolved open‐circuit voltage VOC, short‐circuit current density jSC, fill factor FF, and the efficiency η of a virtual solar cell based on the characterized material are predicted for various temperatures. These data are used to compute temperature coefficients of the aforementioned cell parameters. Our predictions are validated by a comparison with measurement results of cells made from sister wafers, which are analyzed globally and spatially resolved via PL imaging, Lock‐in Thermography, and Light‐Beam‐Induced‐Current measurements. We observed a lower temperature sensitivity of IV parameters in dislocation clusters despite of expecting high changes with temperature, which might be explainable by Shockley‐Read‐Hall (SRH) recombination of impurities like interstitial chromium.