A-Si:H solar cells with embedded silver nanoparticles

Abstract

The application of a light trapping technique based on light scattering by metal nanoparticles through excitation of localized surface plasmons was studied. Our objective was to investigate experimentally the most suitable location for the metal nanoparticles inside hydrogenated amorphous silicon (a-Si:H) solar cells for efficient light scattering. Silver nanoparticles were embedded either at the front, inside, or at the rear of the a-Si:H absorber layer. Embedding the nanoparticles at the back of the absorber layer turned out to be most promising. We found that when the size of the particles was increased, the external quantum efficiency increased for wavelengths longer 600 nm. This was caused by increased light scattering and reduced parasitic absorption for the larger particles. Nonetheless, it proved challenging to enhance the performance of a-Si:H solar cells by embedding silver nanoparticles when state-of-the-art light trapping techniques are already applied.