Highly efficient SiO2 trapezoidal grating-based thin-film solar cell

Abstract

A crystalline silicon thin-film solar cell (c-Si TFSC) with a trapezoidal grating is newly introduced and analyzed. The three-dimensional (3D) finite-difference time-domain (FDTD) method is employed to optimize the geometrical parameters of the trapezoidal grating and hence maximize the light absorption. The proposed trapezoidal grating TFSC offers an optical ultimate efficiency ( η ) of 32.3%, with an enhancement of 81% relative to the conventional TFSC. The light absorption enhancement within wavelength range (300–1100 nm) is based on the diffraction grating, which supports Bloch modes through the suggested solar cell. The electrical characteristics of the proposed design are also studied using the finite-element method. The cell doping concentration, junction thickness, and recombination process are also investigated to further enhance the power conversion efficiency (PCE). The reported design offers a short circuit current density J s c of 24.8 m A / c m 2 and PCE of 12.5% with an improvement of 83% over the conventional TFSC.