Advances in MIS inversion layer solar cells

Recent advances, suited to economic industrial production, are reported for high efficiency MIS inversion layer solar cells with plasma silicon nitride as the dielectric. Substantial improvements in open circuit voltage and reliability of the cells as well as in reproducibility could be achieved by preparing the thin oxide in a chlorine-containing ambient (trichlorethane). The fabrication of silicon nitride/silicon oxynitride double layer AR coatings and their advantages are outlined. As a very important result concerning the interconnection of MIS-IL solar cells into modules it has been demonstrated that the Al/SiO(x)/Si MIS contacts can be reliably bonded with Al ribbons by ultrasonic welding. As to the Al contact grid, line widths as narrow as 8 microns have been realized by simple mask evaporation.