18.2% efficient multicrystalline silicon cell

This paper reports an 18.2% energy conversion efficiency and a 645 mV open-circuit voltage from a multicrystalline silicon cell with a planar front surface tested at the National Renewable Energy Laboratory and Sandia National Laboratories under the 100 mW/cm/sup 2/ AM1.5 global spectrum at 25/spl deg/C. This is one of the highest confirmed conversion efficiencies and the highest confirmed open-circuit voltage ever reported to date for a multicrystalline silicon cell. Significantly, these HEM (heat exchange method) multicrystalline silicon solar cells were processed with the standard PERL (passivated emitter, rear locally-diffused) cell high-temperature processing sequence originally developed for float zoned wafers. The high temperature PERL cell processing did not damage the substrate properties.