Hydrogenated microcrystalline silicon (μc-Si:H) films play different types of roles in the fabrication of single and multi-junction amorphous silicon (a-Si) solar cells and also act as an active layer in microcrystalline cells which forms the bottom cell of micromorph solar cells. The detailed study of doped microcrystalline layers have not been done properly and there is uncertainty about the role of n-microcrystalline layer on the performance of single junction a-Si solar cells (Poissant et al., 2003).