Plasmon effect in Si solar cells coated with a thin polymer film containing silver or gold nanoparticles

摘要

To apply surface plasmon effects to Si solar cells, thin polymer films containing nanoparticles of silver and gold were fabricated using the spin-coating method. Advantages of this method are that it is simple, and that there is no possibility to produce additional crystal defects as surface recombination centers. Thin polymer films showed an absorption peak, anti-reflection effect and the haze ratio increase. In particular, thin polymer films containing gold nanoparticles were promising for improving Si solar cells, because the film had the longest peak wavelength and the lowest reflectance (3.84% at 800 nm), overall haze ratio increase caused by localized surface plasmon. Enhancement ratio in photocurrent conversion efficiency was 12% for single-crystal Si solar cells after being spin-coated with a thin polymer film containing gold nanoparticles. Enhancement ratio of the external quantum efficiency was 22% at the peak wavelength, caused by anti-reflection due to scattering by metal nanoparticles.