Record Efficiencies for EFG and String Ribbon Solar Cells

摘要

Solar cells have been processed on Edge-defined Film-fed Growth and String Ribbon silicon. Based on a standard process developed for different types of multicrystalline materials including evaporation of contacts and photolithography for front-contact formation, optimizations have been implemented to deal with the special needs of these low-cost ribbon materials. Especially a remote plasma hydrogenation step and a change from evaporated to screen-printed aluminium back-surface-field improved cell parameters drastically. Independently confirmed stable efficiencies of 16.7 percent (EFG) and 17.7 percent (String Ribbon) have been achieved on 4cm~2 cells (full area). These values represent the highest stable efficiencies obtained for multicrystalline silicon ribbons so far. Copyright ~C 2003 John Wiley & Sons, Ltd.