| Silicon carbide (SiC) is a promising semiconducting material because of its excellent physical and electrical properties, such as the wide band gap, high electrical breakdown field, high thermal conductivity and so on. These properties make SiC suitable for high-power, high-frequency, high-temperature applications, surface coating, as well as corrosion-resistant coating. SiC is also a very good luminescent material emitting in the visible spectral range from blue to yellow to achieve the optoelectronic integrated circuit. But due to its indirect band gap, SiC based light-emitting diode (LED) could not emit light so efficiently as GaN based LED and GaP based LED. Naturally, people are eager to seek effective means to improve its luminescent efficiency.SiC films, SiC films doped with aluminum (Al), SiC/ZnO/Si system, ZnO/SiC/Si system, andZnO/SiC muti-lay were prepared by the RF-magnetron sputtering technique on p-Si substrates. The as-deposited films were annealed in the temperature range of 400°C～1000°C under nitrogen ambient. The thin films have been characterized by X-Ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-Ray photoelectron spectroscopy (XPS) and Photoluminescence (PL).The results showed the quality of SiC films was significantly improved by increasing the annealing temperature. Annealing is a crucial factor to synthesize SiC. The Si-C peak located at 780 cm-1 shifts to the higher wave numbers due to the change of stoichiometry of the SiC films. The introduction of Al into films hinders the Si particles from reacting completely with C particles to synthesize SiC and hinders the crystalline formation process. The more Al in the films, the more apparent this phenomenon. When more Al was doped in the films, the Si-C peak is shifted to the lower wave numbers (735 cm-1), and more Si particleshave formed which have an important part in the properties of photoluminescence. As to the SiC/ZnO/Si system, we have observed a strong ultraviolet (UV) emission (370nm) from the as-deposited film and an intense violet emission (412nm) from the film...
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