Plasmonic and Dielectric Nanostructures for Improved Performance of Ingan thin Film Solar Cells

In this study, we present Indium-rich InGaN thin film solar cells containing a periodic array of various plasmonic and dielectric nanostructures such as Ag nanogratings (NGs), ITO nanogratings, and Ag nanodiscs (NDs). Finite-difference time-domain (FDTD) simulations were carried out for solar cells containing nanostructures on the back side and on the front side of the solar cells, and an improvement in the performance of the solar cells was compared for the different geometries of these nanostructures. FDTD simulation results demonstrate a broadband absorption enhancement in the active-medium after employing a combination of Ag nanodiscs and ITO nanogratings. The Ag NDs lead to an enhanced surface plasmon-based scattering of longer wavelengths of light, while the ITO NGs lead to enhanced scattering of shorter wavelengths of light. This leads to a significant enhancement in optical absorption in the active medium, as well as in the short circuit current density, $\mathrm{J}_{\text{sc}}$, of these solar cells.