Light trapping is essential to improve the performance of thin film solar cells. In this paper, we performed a parametric optimization of double sided nanopyramid arrays that act as light trapping scheme to increase light absorption in thin-film c-Si solar cells. Our theoretical optimization reveals that the short-circuit current density in a solar cell employing only 1 μm silicon could reach as high as 36 mA/cm2, which is 9% and 224% higher than that of the Y-limit and unpatterned thin film counterparts, respectively. Furthermore, we analyzed the underlying physics of the light absorption enhancement through the electric field intensity profiles.