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.