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Quality and cost of the silicon absorber lay the foundation for high-performance low cost solar cells and modules.In every part of the value chain,evolutionary process improvements are taking place,sometimes even close to revolutionary ones.Our presentation aims to give an overview on respective current activities,and an outlook to possible future trends.Feedstock: Improvements in upgraded metallurgical silicon (umg-Si) and respective crystallization / cell processes let the technological advantage of the currently market dominating Siemens poly-silicon feedstock shrink.Due to the better cost reduction and scaling perspective of umg-Si,it remains a very relevant material for future feedstock supply.Crystallization: Progress in crystallization originates from both higher throughput and higher crystal quality.Continuous feeding,multi-pulling,less oxygen incorporation are some current R&D topics of Czrochalski ingot growth.Vertical gradient freeze (VGF)methods also show exciting improvements: batch loads up to 1 ton,"cast-mono"ingots enabling solar cell efficiencies over 19%,or contamination reduced crucible systems for higher performance.Conventional wafering: Current research focus lies on increased throughput by multi wire cutting with diamond wire or slurry-based structured wires.Progress is made by material improvement,parameter optimization and process modeling.Reduction of kerf seems to find a severe limitation due to the strength of the wire steel,thus opening further R&D fields in wire material research.Kerfless wafering: Significant progress has been reported in silicon epitaxy required for several kerfless wafering approaches.High throughput epitaxy reactors have been developed,making large-area high-quality silicon films or ultrathin wafers possible at low cost.