Light-soaking stability of nano-structure tailored silicon thin film solar cells

In order to overcome the light-soaking degradation of hydrogenated amorphous silicon(a-Si:H) solar cells, we have developed a novel material, called nanostructure tailored silicon, where nano-sized crystallites embedded in the amorphous silicon matrix homogeneously. Size and distribution of the crystallites can be precisely controlled by the layer-by-layer deposition. Degradation ratio of standard a-Si:H solar cells, whose degradation ratio is around 19%, can be remarkably suppressed to less than 5%. Although their initial efficiencies are not as high as standard a-Si:H solar cells, their after-light-soaked efficiencies (7.3%) exceed that of amorphous one (6.8%) on non-textured substrate.