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Because the nature of wide bandgap of SiC, SiC ultraviolet photodetectors prepared under extreme conditions can be applied to biochemical detection, flammable gas plume detection, ozone monitoring, communication and missile plume shortwave ultraviolet radiation detection and other fields, and apply in the harsh environment of the light detector parts and optical sensor development. At present, for the photosensitive properties of SiC also rarely reported, so carry SiC UV Mintel research makes sense. In this study, RF magnetron sputtering technology and composite target SiC films were prepared with Mn, Co, Al-doped SiC films. By X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray energy dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), Hall (Hall) measurement systems, fluorescence spectroscopy, UV - visible spectrophotometer , UV laser and other equipment for the film structure, surface morphology, doping concentration, chemical state, the carrier concentration and conductivity type, photoluminescence, UV absorption, and the photosensitive properties were tested. The results show that: 1) SiC films exist in 2θ = 38.319 ° diffraction peaks found hexagonal crystal structure of 6H-SiC (103), Mn, Co-doped SiC lattice distortion causes, making 6H-SiC (103 ) diffraction peak intensity significantly weakened, Al-doped SiC films appeared at 2θ = 45.322 ° diffraction peak, indicating a 6H-SiC (105) planes of characteristic peaks. 2) Mn, Co-doped SiC films photoluminescence peaks are located 423nm, showed photoluminescence peak at 423nm corresponding to the optical excitation of electrons from the conduction band to the shallow acceptor Si vacancy radiative transitions between energy levels, and its strength depends on the concentration of Si vacancies. 3) Hall measurements found: undoped SiC film carrier concentration is 7.121 × 10 11 / cm 2 , and 6at% Mn, Co, Al-doped SiC sheet carrier concentration is 1.084 × 10 16 / cm 2 , 2.793 × 1015/cm 2 , 3.035 × 10 12 / cm 2 . Undoped SiC films, 4at% Mn-doped SiC films, Co-doped SiC films conductivity type is n-type. Greater 6at% Mn-doped SiC films by the n-type conductivity type into a p-type. Al-doped SiC film conductivity type is p-type. 4) Photosensitive tests found Al, Co, Mn-doped SiC films than the undoped SiC films UV absorption capacity significantly enhanced, and Mn, Co-doped SiC films doped with photosensitive sensitivity increases significantly improved response time becomes shorter. Found that Al-doped SiC films on the wavelength of 280nm ~ 300nm, Co-doped SiC films on the wavelength of 290nm ~ 310nm, Mn-doped SiC films on the wavelength range of 300nm ~ 350nm UV-sensitive, which is a wide-band UV detection device development provides the material foundation. The study also found that, 6at% Mn-doped SiC films are 6at% Co, Al-doped photosensitive sensitivity of 1.5 times and 2 times. Mn, Co, Al-doped SiC films have superior than photosensitive properties of SiC films, is an in photocatalysis, solar cells, ultraviolet sensors and other fields have research value of the film material.
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