• Stegemann, B.; Kegel, J.; Gref, O.; Stürzebecher, U.; Laades, A.; Wolke, K.; Gottschalk, Ch.; Angermann, H.: Conditioning of Textured Silicon Solar Cell Substrates by Wet-Chemical Treatments. In: Nowak, S. [Ed.] : 27th European Photovoltaic Solar Energy Conference and Exhibition ; Frankfurt, Main: EU PVSEC ; 24.9.2012-28.9.2012München: WIP, 2012. - ISBN 3-936338-28-0, p. 547-551

10.4229/27thEUPVSEC2012-2AO.1.3

Abstract:
Different wet-chemical treatments of crystalline Si wafers for the preparation of heterojunction solar cells are optimized with respect to low reflection losses, low recombination losses and long carrier lifetimes. It is demonstrated that a joint optimization of both saw damage etch and texture etch is necessary to control the pyramid morphology. Best results are reached for intermediate saw damage removals and texture etch times. Wet-chemical preconditioning by oxidation in hot water and by using ozone at ambient temperatures is found to yield high-quality surfaces with low defect densities. These methods are considered as low-cost alternatives to conventional approaches. The surface photovoltage (SPV) technique is established as efficient tool for technology optimization and allows a fast and reliable interface characterization and the quantitative determination of interface defect densities.