| 摘要 |
A photovoltaic solar cell device comprises an amorphous semiconductor light absorbing material (Fig. 2; 34, 35), in particular a thin film hydrogenated amorphous silicon (a-Si:H) material; and a band-stop filter structure (Fig. 2; 20) with a given stop band, the structure arranged to attenuate electromagnetic radiation reaching the light absorbing material and having angular frequencies w* within the stop band such that w min < w*< w max, wherein w min and w max are such that angular frequencies w* correspond to electronic excitations hw* from valence band tail (VBT) states of the amorphous material to conduction band tail (CBT) states of the amorphous material. The band stop filter may comprise a Bragg reflector. Absorption of energies within the stop band are thought to contribute to photodegredation of the solar devices. |
