Al/a-Si:H bilayer thin films were deposited on glass substrate by thermal evaporation and plasma-enhanced chemical-vapor-deposition in a specially designed one-chamber deposition apparatus. Scanning electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy were used to study the morphology, crystallization and the shift of Si-2p binding energy, respectively. The crystalline silicon was formed at a low temperature of approximately 250 degreesC in, the Al/a-Si:H bilayer thin film. The intermixed layer of (Al)-(a-Si:H) plays an important role in the crystallization of silicon. The content of crystalline Si, which is related to a dome-like microstructure, increases with increasing thickness of the intermixed layer formed due to the high diffusion rate of At atoms at high temperature or larger amounts of Al diffused into a-Si:H layer with the increase in thickness of the Al sublayer. The Si-2p binding energy of c-Si is approximately 99.23 eV while a-Si:H energy shifts from approximately 98.66 to 98.87 eV in the Al/a-Si:H bilayer thin films with different thickness of the Al sublayer.