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Industrial mass production of solar cells is at a transition toward carrier‐selective junction solar cells with passivating contacts such as TOPCon, POLO, or heterojunction technology (HJT). At the same time, many manufacturers consider switching from p‐type Cz‐Si to n‐type Cz‐Si wafers. This contribution indicates that Ga‐doped p‐type Cz‐Si material is still a viable option for the new type of devices while giving an opportunity to benefit from lower wafer cost. The minority carrier diffusion lengths that are an order of magnitude larger than the thickness of the studied HJT and TOPCoRE devices are reported. Stability aspects for operation in the field are discussed. Best TOPCoRE solar cells on Ga‐doped Cz‐Si show a 0.2% higher efficiency than their co‐processed n‐type counterparts. [ABSTRACT FROM AUTHOR]

The current–voltage measurement is the most important measurement in solar cell quality control. As the contacting process of cells results in mechanical stress and consumes a significant amount of measurement time, this work presents an IV characterization based on contactless measurements only. An empirical model is introduced that can derive the full IV curve and IV parameters as the open‐circuit voltage, short‐circuit current density, fill factor, and efficiency. As a basis, a series of photoluminescence and contactless electroluminescence images and spectral reflectance measurements are used. An advantage of the model's convolutional neural network design lies in the semantic compression of local image structures across the input data. Within an ablation study, it is shown that the empirical model is well suited to combine these data sources, which is the optimal input configuration for contactless IV derivation. The accuracy, e.g., with an error in efficiency of 0.035%abs and correlation of over 99%, is similar to comparing two contacting IV measurement devices. The contactless IV curves also have a close fit to their contacted counterparts. Within simulations on module level, it is demonstrated that contactless binning performs as well as contacting binning and does not result in any additional mismatch loss. [ABSTRACT FROM AUTHOR]