The hydrogenated nano-crystalline silicon (nc-Si:H) films have been deposited with plasma enhanced chemical vapor deposition method. The microstructure of these films has been studied by transmission electron microscopy and high resolution transmission electron microscopy. The nc-Si:H films show fiber texture structure. The fractal dimension of this structure has been calculated with a Fourier filtered image. The relationship between conductivity and temperature has also been studied and the mechanism of electron conduction is discussed.