Study Of Nano-diamond Coating FED Cathode And The Improvement Of Its Preparation Technics

FED devices with all the advantages of CRT and flat panel displayers have become a hot study issue nowadays .Diamond materials have very good physical and chemical abilities . Using diamond to work as cathode material is an important direction in the development of novel FED devices.The preparation technics of the nanocrystalline-diamond powder coating FED cathode is researched. The diamond dispersant formation is improved . The uniformity of the diamond coating becomes better by improving the coating method . The heat uniformity for annealing is also improved . RF plasma techniques is used to improve the effects and efficiency of hydrogen plasma treatment.The influences of thicknesses of the TiC interface layer and diamond coating on the field emission properties are primarily explored and the ideal combination of annealing temperature and coating thickness is decided. The mechanism of electron's transportation in the diamond coating is researched . The emission capability is improved by mixing Ti nano-particles into the diamond coating. The plasma treatment time , pressure and the temperature of substrate are optimized and the active mechanism between hydrogen plasma and diamond coating is researched . A lot of emission photos are taken and the main reasons influencing the uniformity of lighting are analysed.XRD, SEM, EDS, AFM, Raman Spectra are used to test and analyse the prepared FED cathodes . Using the best preparation technics , we achieve a best threshold voltage of 1.9 V/μ m and the biggest current density of 61 u A/cm2 under an electric field of 18 V/μm.