Polycrystalline silicon thin-film solar cells on ZnO:Al-coated glass substrates

Polycrystalline Si (poly-Si) thin-film solar cells feature the potential to reach very high efficiencies at low costs. This paper addresses the development of poly-Si thin-film solar cells on ZnO:Al-coated glass substrates. This development is based on the fact that the properties of capped ZnO:Al layers stay the same (or even improve) upon annealing at temperatures far above the deposition temperature of the ZnO:Al. Three different approaches have been used to form the poly-Si films (solid phase crystallization, direct growth of poly-Si, and a `seed layer' concept). Solar cells have been prepared with all three approaches. So far the best results have been obtained by direct growth of poly-Si and the `seed layer' concept. Our results show that the preparation of poly-Si thin-film solar cells is compatible with the utilization of ZnO:Al-coated glass substrates.