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Vacuum microelectronic devices with field emitters possess many advantages over vacuum devices and solid-state devices. Applications of field emitter devices can be largely found in flat panel displays and RF power amplifiers. For such applications, the field emitters must have a high yield and relatively low cost. Among the various field emitter structures, gated cone-type emitters provide the highest emission current density. For various applicatios in microelectonics and in particular vacuum microelectronics, negative electron affinity (NEA) is a highly desired property of the material used in devices. Either obtaining the NEA property or lowering surface and interface barriers can substantially increase the operational efficiency and reduce the power consumption of the entire device. Selecting proper materials such as a diamond can cahieve such an objective. In light of above concerns, this investingation fabricates the gated cone-shaped diamond field emitter array by using bias-assisted microwave plasma chemical vapoor deposition system (BAMPCVD) with a two-step deopositon method. A cone-shaped diamond is grown on 8μm gated circle patterned silicon substrates, which are fabricated with. standard photolithography and RIE techniques. the reactive gases used in depostiton are a mixture of CH4-H2 Scanning electron microscopy (SEM), Raman spectroscopy, Auger electron spectroscopy (AES) are used to examine the morphology, crystallity and quality of the as-deposited cone-shaped diamond. According to our results. the cone-shaped diamond's density increases with an increasing negative bias Voltage. In addition, the change of methane concentration influences the quality of conic diamond, deposition rate and size. Also discussed herein is the possible mechanism and some phenomena associated with the formation of a cone-shaped diamond by BAMPCVD system.
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