Multi-type particle layer enhanced absorption for photovoltaics

We discuss regular particle arrays as nanostructured front layers for 3rd generation photovoltaic devices. A rigorous plane-wave method is used to investigate multi-type particle layers combining different radii and configurations. The absorbance is enhanced compared to the bare wafer and on mixing particles we demonstrate a broadband boost in the absorbance within the photo-active region. Efficiency enhancement in terms of short circuit current is studied for varying geometries. Si multi-type layers achieved up to 33% improvement without yet standard anti-reflection coatings. Metal multi-type layers show strong parasitic absorption and boost the absorbance only in narrow wavelength regions and no efficiency enhancement is observed.