Design Guidelines for High Efficiency Plasmonics Silicon Solar Cells

Abstract

We report a novel solar cell design concept, for high optical absorption in the thin active layer of photovoltaic devices due to localized surface plasmon effects arising on the employed metallic nanoparticle arrays. The proposed solar cell geometry consists of sub-wavelength nanotextured surface in combination with plasmonics metal nanoparticles. The detailed balance analysis is carried out for the limiting efficiency of an optimized nanotextured surface in combination with the gold (Au) nanoparticle arrays described herein. The ultimate efficiency of the optimized nanostructured silicon surface decorated by the Au nanoparticle arrays is 39.67 %, which compares favorably with the ultimate efficiency of 31.11 % for an optimized nanotextured surface without Au nanoparticles. For the proposed geometry of the solar cell, the maximum short circuit current density (J SC) and the power conversion efficiency (PCE) of 31.57 mA/cm2 and 25.42 %, respectively, are achieved on a single-crystal silicon layer of thickness 2.8 μm, compared to the predicted J SC and PCE values of 25.45 mA/cm2 and 20.87 %, respectively, for an optimized structure of the same thickness without Au plasmonics effects. The influence of a silicon dioxide/silicon nitride (SiO2/Si3N4) stack as a dielectric spacer layer, which could also serves as a surface passivation for nanotextured surface, on the optical absorption performance of plasmonics Au nanoparticle is also presented.