Plasmonic for photovoltaic devices

Light trapping application is crucial in thin-film silicon solar cells in order to increase light absorption particularly at wavelengths close to the band gap of silicon. In this report, we pursue the suitability of using surface plasmon light trapping scheme for enhancing the absorbance of silicon solar cells. Particularly different shapes of plasmonic nanostructure are compared using a model based on finite domain time difference (FDTD) theory.Three steps analysis are performed. Initial observation based on single particle scattering model analysis shows that sphere and hemisphere is a suitable candidate for thin film solar cell application. This result is double confirmed with a thin film plasmonic solar cell model which shows a photocurrent enhancement of 30% in the case of spherical with diameter of 150 nm and periodicity of approximately 350 nm and 10% photocurrent enhancement in the case of hemispherical shape with 100 nm radius of curvature and periodicity of approximately 380 nm whereas for the rest of shapes (square and cylindrical), no photocurrent enhancement is observed. Using an optimized parameter Au is compared to Ag. It shows that Ag is more suitable compare to Au since Au has larger imaginary permittivity compare to Ag. Absorption profile is plotted and the enhancement is attributed due to the dominancy of scattering cross section in both hemisphere and sphere once the diameter reaches above 150 nm. Dominancy of scattering cross section leads to enhanced forward scattering in both cases. It‟s also observed that the excitation of near-field localized surface plasmon in the sphere case makes it a more suitable candidate for plasmon light trapping application.Bachelor of Engineering (Materials Engineering