Publications by authors named "Rolf Brendel"
Editorial to the proceedings of the 11th international conference on crystalline silicon photovoltaics.
Sol Energy Mater Sol Cells
June 2022
Article Synopsis
- The study investigates how light-induced degradation affects high-efficiency solar cells made from Ga-doped Czochralski-grown silicon under varying elevated temperatures (80-160°C).
- Degradation increases with temperature up to 140°C, where it reaches 0.4% reduction in energy conversion efficiency, primarily affecting short-circuit current and fill factor.
- Unlike solar cells made from B-doped silicon, which degrade more significantly, those tested show a potential improvement in efficiency (up to 0.2%) after prolonged exposure to specific conditions, leading to stable performance above 22%.
Article Synopsis
- The study explores using simulation to identify effective cell structures that combine poly-Si on oxide junctions with industrial crystalline silicon solar cells for improved efficiency.
- The POLO BJ and POLO IBC structures show potential efficiency gains of 1.0% and 1.8% respectively compared to a baseline PERC cell, leading to discussions on process challenges.
- Concepts with poly-Si contacts for both polarities indicate even higher efficiency improvements, suggesting further research is needed in poly-Si structuring and screen-printing.
Spectrophotometers are operated in numerous fields of science and industry for a variety of applications. In order to provide confidence for the measured data, analyzing the associated uncertainty is valuable. However, the uncertainty of the measurement results is often unknown or reduced to sample-related contributions.
View Article and Find Full Text PDFWe demonstrate for the first time the successful layer transfer of an epitaxially grown monocrystalline Si film from a purely chemically etched porous Si substrate of 150 mm diameter to a glass carrier. The surface conditioning for all Si layer transfer processes based on porous Si has been, up to now without exception, carried out by electrochemical etching. In contrast, our chemical stain etching process uses an aqueous HF-rich HF/HNO₃ solution.
View Article and Find Full Text PDFWe report in detail on the luminescence imaging setup developed within the last years in our laboratory. In this setup, the luminescence emission of silicon solar cells or silicon wafers is analyzed quantitatively. Charge carriers are excited electrically (electroluminescence) using a power supply for carrier injection or optically (photoluminescence) using a laser as illumination source.
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