Back Junction n-type Silicon Heterojunction Solar Cells with V2O5 Hole-selective Contact

Abstract In this work, a back junction solar cell design is explored for n-type crystalline silicon by using thermally evaporated V 2 O 5 as a rear hole contact and n + amorphous silicon (a-Si:H) as a front electron contact. Photoconductance measurements revealed an implicit open-circuit voltage ( i-V OC ) of 670 mV for the solar cell precursor (before metallization), achieved by maximizing the work function of V 2 O 5 with a thin nickel capping layer. The V OC value of the finished device was lower than projected at 617 mV, most likely due to poor passivation of the active area perimeter. Nonetheless, an efficiency of 14.2% was achieved (in polished substrates), proving the potential of such a novel structure.