SiO2 layer grown by rapid thermal oxidation and SiNx layer were used for passivating the surface of n-type silicon solar cell, instead of only SiNx layer generally used in photovoltaic industry. The rapid thermal oxidation provides the reduction of processing time and avoids bulk life time degradation during the processing. Improvement of 30 mV in Voc and 2.7 mA/cm2 in Jsc was obtained by applying these two layers. This improvement led to fabrication of a large area (239 cm2) n-type solar cell with 17.34% efficiency. Internal quantum efficiency measurement indicates that the improvement comes from the front side passivation, but not the rear side, by using SiO2/SiNx stack.
