The microstructure and open-circuit voltage of n-i-p microcrystalline silicon solar cells were discussed. A mixed phase layer consisting of amorphous plus microcrystalline material was observed at the bottom of the solar cell and identified as one of the key microstructural features of the device. Results underlined the importance of the first stages of growth of the intrinsic (i) layer for the fabrication of high- Voc n-i-p microcrystalline solar cells.