High-efficiency crystalline si thin film solar cells with Si nanopillar array textured surfaces

In this paper, high-efficiency crystalline Si thin film solar cells are reported via the incorporation of the Si nanopillar (SiNP) array textured surface. The power conversion efficiency of ~18.1% is predicted for the cell configuration of the 1000 nm thick SiNP array (array periodicity: 500 nm; SiNP diameter: 250 nm) + 800 nm thick underlying Si film with the minority carrier diffusion length of ~0.6 μm based on the optical and electrical calculations. This work points out the potential of the aforementioned cell structure in boosting the performance of Si thin film based solar cells while maintaining the low costs without using high grade raw materials. Except the device performance projection, the underlying physics responsible is also clarified.