Persons

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A promising material for cold cathodes creation are carbon films with both acceptable emission properties and satisfactory adhesion to the substrate. It is known that inclusions of metallic elements (chromium, titanium, etc.) improve the adhesion of the carbon film to the substrate. One of the methods for producing coatings based on carbon and titanium is electric arc spraying of a Ti/C composite cathode in an argon atmosphere. The disadvantage of this method is the presence in the total plasma flow of carbon microparticles, which are sources of structural defects in the growing film. Magnetic separation of carbon plasma solves the above problem. In this work, composite metal-carbon films were obtained by simultaneous electric arc spraying of graphite in a magnetic field and of titanium from two evaporators. The composition of the films was studied by Raman spectroscopy (RS) and X-ray photoelectron spectroscopy (XPS). It has been established that the samples obtained are composite films consisting of graphite nanoparticles, TiC nanoclusters or TiC, titanium oxides, and titanium carbide TiC Ncompounds.

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The results of studying the field emission properties of various conductors show the perspective of their use in the devices of microelectronics, X-ray tubes and light sources. For smooth conductor surfaces with an electron work function of about 2 to 5 eV, the electric field, at which an insignificant emission appears, is extremely high (about 107 V/cm), which creates certain limitations on the methods of the cathode formation. The existing methods of obtaining the cathodes with the low values of field permit to create the device structures, complying with the requirements of the developers of the systems. Therefore, in connection with this studying the methods of creating auto-emission cathodes of large area with homogeneous emission properties of the working surface and low operating voltages (<1 keV) is actual. In the paper the Spindt cathode with an amount of silicon micro-tips up to 6000 and the packing density 0f 1×10 cm has been studied. By an electric arc method the arc of titanium and carbon nitride films was deposited on the micropoint. It has been shown that the cathode has low emission uniformity due to the problem of reproducing the micro-points of the same shape and size. A cathode has been constructed on the basis of a microchannel plate with 6µ diameter channels, inside of which the graphite-like nanostructures were formed by the electric arc method. It has been found that as a result of the enhancement of the electron flux in the channel of the multichannel plates it is possible to significantly reduce the operating voltage (<1 keV) and to obtain a high emission uniformity at the maximum permissible value of the output current.

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