Antireflective submicrometer gratings on thin-film silicon solar cells for light-absorption enhancement

Abstract

This study reports highly efficient light-absorbing structures based on submicrometer gratings (SMGs) for thin-film crystalline silicon solar cells. The integration of SMGs into the cell structure leads to superior broadband antireflection properties compared to conventional antireflection coatings. With careful design optimization, an improvement of the cell efficiency of nearly 25.1% was obtained compared to double-layer coated solar cells. Optimized SMG structures were fabricated on a silicon substrate using interference lithography and a lenslike shape transfer process. The fabricated SMG structures exhibited low reflectivity in the wavelength range of 300-1200 nm, indicating good agreement with the simulated results. (C) 2010 Optical Society of America