Dependences of amorphous structure on bias voltage and annealing in silicon-carbon alloys

The amorphous silicon-carbon alloy films have been obtained by filtered cathodic vacuum arc (FCVA) technique. The typical carbon composition is about 32% in the film by using a 50% target (the atomic ratio), which is characterized by X-ray photoemission spectroscopy. The films deposited with various bias voltages and annealed in different temperature were characterized by Raman spectrometer, atomic force microscope, and X-ray diffraction. The disorder of Si-C network increased with using the high bias voltages during the deposition. This high disorder in the film with high bias voltages induces the smaller nanometer crystallites after annealed in 1000°C than low bias. The Raman peaks shift to the high frequency with increasing the annealing temperature up to 750°C due to the increasing of nanometer grain size at the same bias. A sharp transition from nanocrystalline to polycrystalline can be observed when the films annealed under 1000°C.