Selective Growth of Ca_2Si Film or CasSi_3 Film in Ca-Si System by R.F MS by Annealing

摘要

Ca films were deposited directly on Si(100) substrates by Radio Frequency (R.F.) magnetron sputtering system (MS) and subsequent were pre-annealed at 600°C for 2h in situ. Finally, the samples were annealed again at 750°C, 782°C, 795°C, 800°C and 850°C for 1h in a vacuum furnace by an interdiffusion process between the deposited particles and clusters and Si atoms, respectively. The structural and morphological features of the resultant films were tested by XRD, SEM, EDAX and FT-IR. The cubic phase Ca_2Si film and the tetragonal phase Ca_5Si_3 film were grown directly and individually on Si(100) substrates, respectively. The experimental results indicate that the selective growth of a single phase Ca-silicide in Ca-Si system in the existence of multiple silicide phases depends on sputtering condition and annealing in twice. In addition, the electronic structure of stressed the cubic phase Ca2Si was calculated using the first-principle methods based on plane-wave pseudo-potential theory.