Morphology Optimization of Silver Nanoparticles Used to Improve the Light Absorption in Thin-Film Silicon Solar Cells

Silver nanoparticle (NP) arrays are used as antireflection coating to enhance light trapping capability of thin-film silicon solar cells. In this paper, we theoretically investigate the differences of light absorption distribution between the silver NP (spherical and hemispherical) array layer and the crystalline silicon (CS) substrate. Compared to the naked silicon of the same thickness, the results show that only the flattened hemispherical silver NPs can really improve the light trapping ability and make the light absorption of CS body increase by 26%; the optimum ratio of lateral (NP diameter divided by the array periodicity) and longitudinal (NP height divided by diameter) are 0.86 and 0.22, respectively.