CONDITIONING OF TEXTURED SILICON SOLAR CELL SUBSTRATES BY WET-CHEMICAL TREATMENTS

摘要

Different wet-chemical treatments of crystalline Si wafers for the preparation of heterojunction solarcells are optimized with respect to low reflection losses, low recombination losses and long carrier lifetimes. It isdemonstrated that a joint optimization of both saw damage etch and texture etch is necessary to control the pyramidmorphology. Best results are reached for intermediate saw damage removals and texture etch times. Wet-chemicalpreconditioning by oxidation in hot water and by using ozone at ambient temperatures is found to yield high-qualitysurfaces 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 afast and reliable interface characterization and the quantitative determination of interface defect densities.