Grating structures are expected to have considerably better spectral response to short wavelengths than in conventional diffused structures. This paper reviews the experimental results and design principles of grating Si cells. Numerical simulations were done to analyze the Si grating cell performance. The deep junction concept is in contrast to the conventional shallow junction cells. The computational results indicate that BSF are essential to be incorporated in the grating structure and the current output of a grating cell can be substantially increased by the incorporation of minority carrier mirrors.