High-efficiency Multicrystalline Silicon Solar Cells using Standard High-temperature, Float-zoned Cell Processing

This paper reports recent results of fabricating multicrystalline silicon solar cells with the standard PERL (passivated emitter, rear locally-diffused) cell high-temperature processing sequence originally developed for float-zoned wafers. One of these multicrystalline silicon cells with a planar front surface demonstrated a 645-mV open-circuit voltage and 18.2% energy conversion efficiency tested at the National Renewable Energy Laboratory and Sandia National Laboratories under the 100 mW cm−2 AM1.5 global spectrum at 25°C. This is the highest confirmed voltage and one of the highest confirmed conversion efficiencies ever reported to date for a multicrystalline silicon cell. Further optimization of the standard PERL processing and texturing of the cell surfaces is expected to improve the cell efficiency to over 19% in the near future.