Buried contact solar cells on multicrystalline silicon with optimised bulk and surface passivation

This paper describes the further development of an industrial processing sequence for large area multicrystalline silicon solar cells applying the buried contact technology for solar cell metallisation. Passivation of crystal defects was investigated by remote plasma hydrogenation at different stages of the processing sequence. The reduction of emitter recombination was examined by the optimisation of the emitter diffusion as well as the growth of a thermal oxide. A record high efficiency for a large area multicrystalline silicon solar cell of 17.6% (V/sub oc/=632.5 mV, J/sub sc/=35.85 mA/cm/sup 2/, FF=77.7%, cell area 144 cm/sup 2/, independently confirmed at FhG-ISE, Germany) was achieved. For this cell, a loss analysis was done to determine the potential for further improvements in solar cell efficiency.