Employing dielectric diffractive structures in solar cells - a numerical study

We study numerically in detail optical effects occurring during the interaction of light with dielectric gratings and explain how they can be exploited to enhance light absorption in thin-film solar cells. We analyze in depth two scenarios with practical relevance where dielectric gratings are incorporated. The first is an one-dimensional, binary grating, which can be manufactured lithographically. The second is a two-dimensional grating of dielectric spheres that can be fabricated employing self organization processes on pre-textured substrates. From a universally valid point of view, we finally outline strategies to optimize the geometry of textured surfaces permitting for a maximization of absorption in a solar cell. Absorption enhancement in a solar cell due to the presence of a grating. The right picturre shows the electric field distribution if a plane wave illuminates this grating. (C) 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim