High-efficiency screen-printed silicon ribbon solar cells by effective defect passivation and rapid thermal processing

A conversion efficiency of 15.9% has been achieved on low-cost edge-defined film-fed grown silicon ribbon solar cells. This represents an improvement over the previously reported efficiencies for silicon ribbon solar cells with manufacturable screen-printed contacts and single layer silicon nitride (SiNx) antireflection coating. Two separate rapid thermal processing cycles with fast ramp-up and cooling rates contributed to the enhancement in cell efficiency. The fast ramp-up rate improved the quality of back surface field and contacts; and a short firing time with a fast cooling rate improved contacts and the SiNx-induced hydrogen passivation of defects, resulting in bulk lifetime enhancement from similar to2 to similar to50 mus. (C) 2003 American Institute of Physics.