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The photogenerated current of solar cells can be enhanced by light management with surface structures. For solar cells with optically thin absorbing layers, it is especially important to take advantage of this fact through light trapping. The general idea behind light trapping is to use structures, either on the front surface or on the back, to scatter light rays to maximize their path length in the absorber. In this paper, we investigate the potential of chaotic scattering for light trapping. It is well known that the trajectories close to the invariant set of a chaotic scatterer spend a very long time inside of the scatterer before they leave. The invariant set, also called the chaotic repeller, contains all rays of in nite length that never enter or leave the region of the scatterer. If chaotic repellers exist in a system, a chaotic dynamics is present in the scatterer. As a model system, we investigate an elliptical dome structure placed on top of an optically thin absorbing lm, a system inspired by the chaotic Bunimovich stadium. A classical ray-tracing program has been developed to classify the scattering dynamics and to evaluate the absorption e ciency, modeled with Beer-Lambert's law. We nd that there is a strong correlation between the enhancement of absorption e ciency and the onset of chaotic scattering in such systems. The dynamics of the systems was shown to be chaotic by their positive Lyapunov exponents and the noninteger fractal dimension of their scattering fractals.

To reduce costs, the solar cell industry aims at producing thinner solar cells.Structuring the surfaces of optically thin devices is important for avoiding transmission-related losses and, hence, increasing their efficiency. Light trapping leads to longer optical pathlengths and increased absorption of energy. In addition, resonances in the nanostructures enhance the absorption in the energy-converting material. Further, resonances in periodic structures may couple with each other and thereby increase the absorption. Here, we establish a model system consisting of a multilayered solar cell to study resonances and coupling of resonances in a onedimensional system. We show that resonances in energy-converting and nonenergy converting layers exist, evaluate the resonances and the coupling of resonances in different thin-film systems, and show how they affect the total absorption of energy in the energy-converting layer. We optimize the parameters of the multilayered thin-film systems to achieve an increase in the amount of the absorbed energy. We find that resonances in nonabsorbing material at the top may lead to absorption enhancement, while we cannot find any enhancement effect due to the coupling of resonances. © The Authors. Published by SPIE under a Creative Commons Attribution 4.0 Unported License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its DOI.

We present the properties of Cr-doped zinc sulfide (ZnS:Cr) films deposited on Si(100) by pulsed laser deposition (PLD). The films are studied for solar cell application, and to have a high absorption a high Cr content (2.0-5.0 at.%) was intended. It is determined by energy-dispersive X-ray spectroscopy that Cr is relatively uniformely distributed, and Cr increase corresponds to Zn decrease.The results indicate that most Cr atoms substitute Zn sites. Consistently, electron energy loss and X-ray photoelectron spectroscopy (XPS) showed that the films contain mainly Cr increasing Cr content, and at a given Cr content, increases with increasing growth temperature.