Development and characterization of polysilicon emitter solar cells

Abstract

Solar cells with emitters consisting of a very thin (<20 nm) layer of silicon deposited in the polycrystalline phase overlaid with a thicker (≈100 nm) layer of recrystallized amorphous material were fabricated and characterized. Both layers were formed by low-pressure chemical vapor deposition with heavy in situ phosphorus doping. The highest temperature used in processing was 650 °C. Short-circuit current densities (Jsc) of 30 mA cm−2 combined with fill factors close to 0.8 were achieved under simulated 100 mW cm−2 AM1.5 illumination. Open-circuit voltages as high as 669 mV at 28 °C were obtained for cells formed on high-quality 0.1 Ω cm float zone substrates when Jsc was set to 32 mA cm−2.