Design of a broadband anti-reflection coating for solar cells

Reflection of incident light from the surface of solar cells is one of the major mechanisms seriously affecting the photovoltaic transform efficiency of the solar cells.To reduce the reflection, a two dimensional submicron anti-reflection coating with the incident wavelength from 400 nm to 1 100 nm was designed.The designed structure was mainly composed of a ZnS film, an MgF2 film and a two dimensional submicron grating.The reflection efficiency of the structure was calculated by the rigorous coupled wave analysis theory.The average reflection efficiency of the designed anti-reflection coating was 7.76% when the incident angle varied from 0° to 80° with the height of the ZnS film, the MgF2 film, the depth and the pitch of the grating of 50 nm, 150 nm, 200 nm and 400 nm respectively.Results show that the designed anti-reflection coating can effectively reduce the reflection from the Si surface to improve the photovoltaic transform efficiency of the solar cells.