Effects of magnesium film thickness and annealing temperature on formation of Mg_2Si films on silicon (111) substrate deposited by magnetron sputtering

摘要

Magnesium films of various thicknesses were first deposited on silicon (111) substrates by magnetron sputtering method and then annealed in annealing furnace filled with argon gas. The effects of the magnesium film thickness and the annealing temperature on the formation of Mg_2Si films were investigated by means of X-ray diffraction (XRD) and scanning electron microscopy (SEM). The Mg_2Si thin films thus obtained were found to be polycrystalline and the Mg_2Si (220) orientation is preferred regardless of the magnesium film thickness and annealing temperature. XRD results indicate that high quality magnesium silicide films are produced if the magnesium/silicon samples are annealed at 400℃ for 5 h. Otherwise, the synthesized films annealed at annealing temperatures lower than 350℃ or higher than 450℃ contain magnesium crystallites or magnesium oxide. SEM images have revealed that microstructure grains in the polycrystalline films are about 1-5μm in dimensions, and the texture of the Mg_2Si films becomes denser and more homogeneous as the thickness of the magnesium film increases.