A structure is developed to help improve the TCO/p contact and efficiency of the solar cell. A p–i–n amorphous silicon (a-Si:H) solar cell with high-conversion efficiency is presented via use of a double p-type window layer composed of microcrystalline silicon and amorphous silicon carbide. The best efficiency is obtained for a glass/textured TCO/p-μc-Si:H/p-a-SiC:H/buffer/i-a-Si:H/n-μc-Si:H/GZO/Ag structure. Using a SnO 2 /GZO bi-layer and a p-type hydrogenated microcrystalline silicon (p-μc-Si:H) layer between the TCO/p-a-SiC:H interface improves the photovoltaic performance due to reduction of the surface potential barrier. Layer thickness, B 2 H 6 /SiH 4 ratio and hydrogen dilution ratio of the p-μc-Si:H layer are studied experimentally. It is clearly shown that the double window layer can improve solar cell efficiency. An initial conversion efficiency of 10.63% is achieved for the a-Si:H solar cell.