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In this study, we introduce a temperature screening image analysis to investigate the temperature dependence of boron-oxygen-related defect regeneration achieved by using one sample. For that purpose, we induce a temperature gradient in a single sample over a broad temperature range in our laser-based rapid thermal processing furnace, while other influencing factors are kept constant. Spatially resolved measurements of the temperature during the regeneration process (thermographic images) and photoluminescence (PL) images at different boron-oxygen-related defect states are recorded. By a pixelwise assignment of the PL images to the temperature image, the effectiveness of the regeneration process in terms of regeneration completeness is evaluated for each pixel. In this experiment, we investigate the temperature dependence of a boron-oxygen-related defect regeneration in a temperature range of 100-500 °C for different treatment times of 2-30 s at an illumination intensity of 100 kW/m². Thereby, we determine the temperature regimes that allow for efficient regeneration for the respective regeneration parameter set with a single sample. The results can be used for industrial optimization of a boron-oxygen-related defect regeneration process. Furthermore, this technique can also be applied to other temperature-dependent process optimizations and even fundamental research.

Light-induced degradation (LID) of multicrystalline silicon (mc-Si) solar cell performance has been reported to be surprisingly strong for conditions relevant under field operation. In paticular, solar cells with dielectrically passivated rear sides such as passivated emitter and rear cells are affected by this LID effect that can cause a loss of more than 10%rel in cell efficiency. With the root cause for the observed degradation being unknown to date, the underlying defect, however, has also been reported to be permanently deactivated under the same conditions at even longer time scales. However, a severe power loss due to the mc-Si specific LID is observed before the cells recover due to the long time scales of the regeneration under these conditions. Hence, regeneration on short time scales similar to the fast regeneration processes being reported for the boron–oxygen defect within p-type Czochralski-grown silicon is highly desirable also for p-type mc-Si, especially since mc-Si currently dominates industrial solar cell production. Within this work, partial regeneration of the defect causing the mc-Si specific LID is shown to be possible within less than 30 s, reducing the impact of LID by up to 60%, which leads to a significantly increased performance of the regenerated mc-Si solar cells.