| abstract |
One embodiment of the present invention provides a solar cell. The solar cell includes a substrate; a polycrystalline Si (poly-Si) thin-film layer which includes a p + layer situated above the substrate, wherein the poly-Si thin-film layer is hydrogenated; a contact under-layer situated between the foreign substrate and the poly-Si thin-film layer; a metal layer situated below the contact layer, wherein part of the metal layer reaches the p + layer through the contact under-layer; an n-type doped amorphous-Si (a-Si) thin-film layer situated above the poly-Si thin-film layer forming a heterojunction; an optional intrinsic layer situated between the poly-Si thin-film layer and the n-type doped a-Si thin-film layer; a transparent conductive layer situated above the n-type doped a-Si thin-film layer; and a front-side electrode situated above the transparent conductive layer. |