Significant light absorption enhancement in silicon thin film tandem solar cells with metallic nanoparticles.

Enhancing the light absorption in microcrystalline silicon bottom cell of a silicon-based tandem solar cell for photocurrent matching holds the key to achieving the overall solar cell performance breakthroughs. Here, we present a concept for significantly improving the absorption of both subcells simultaneously by simply applying tailored metallic nanoparticles both on the top and at the rear surfaces of the solar cells. Significant light absorption enhancement as large as 56% has been achieved in the bottom subcells. More importantly the thickness of the microcrystalline layer can be reduced by 57% without compromising the optical performance of the tandem solar cell, providing a cost-effective strategy for high performance tandem solar cells.