Absorption enhancement in thin film a-Si solar cells with double-sided SiO₂ particle layers

Light absorption enhancement is very important for improving the power conversion efficiency of a thin film a-Si solar cell. In this paper, a thin-film a-Si solar cell model with double-sided SiO₂ particle layers is designed, and then the underlying mechanism of absorption enhancement is investigated by finite difference time domain (FDTD) simulation; finally the feasible experimental scheme for preparing the SiO₂ particle layer is discussed. It is found that the top and bottom SiO₂ particle layers play an important role in anti-reflection and light trapping, respectively. The light absorption of the cell with double-sided SiO₂ layers greatly increases in a wavelength range of 300 nm-800 nm, and the ultimate efficiency increases more than 22% compared with that of the flat device. The cell model with double-sided SiO₂ particle layers reported here can be used in varieties of thin film solar cells to further improve their performances.