Reduction of the surface reflectance of an amorphous silicon solar cell by a moth-eye structure

Résumé

Hydrogenated amorphous silicon (a-Si:H) is widely used as absorber layer in thin-film silicon solar cells. The performances of a-Si:H solar cells can be enhanced by reducing the surface reflection of the active layer. Here, we propose a moth-eye antireflective structure with conical profile to reduce the surface reflection of a-Si:H. By optimizing the dimensional parameters of the conical nipple arrays, it is found that  the average reflectance from the a-Si:H surface can be reduced up to 1.26% under normal incidence in the wavelength range 300-900nm, allowing to expect a relatively high short-circuit current density of 17.123 mA/cm² in the same wavelength range. It is also observed that the reflectance is below 3% for angles of incidence lower than 50° and for two types of light polarisation.