Design Of Plasmonic Back Structures For Effciency Of Thin-Film Solar Cells

In recent years, the study of thin films solar cell has attracted much interest, because their easy of fabrication, procession temperatures and low cost has obtained great achievements. In order to improve the energy conversion efficiency of solar cells. Light trapping is particularly critical in tin films solar cells in order to increase light absorption and enhance cell efficiency. We investigate the possibility to enhance the absorption in solar cell by employing localized plasmon polaritons excited in metallic nanoparticles. We identify two reasons for increased absorption, namely, the giant near-field enhancement and enhanced scattering cross section upon exciting localized plasmon polaritons. In this paper, We use monocrystalline silicon as the substrate material, the surface of the substrate covered with a layer of silver cylindrical nanoparticles, then optimize the structure of the particles with a finite difference time domain(FDTD)method to study the surface plasmon resonance on the impact of solar absorptance. We also should calculate absorption factor as the change of structural parameters of nanoparticles, and analyze that the particles in the back play an important role in light absorption.Studied have shown that at the interface between monocrystalline silicon and metal materials, the excitation of surface plasmons polaritons leads to obvious absorption enhancements for different cylindrical nanoparticles and periods. We founded that the optimized structure for period is120nm, radius is100nm, height is60nm, can achieve an absorption factor is1.6.