The current state of field-emission electronics is reviewed and the basic types of field-emission cathodes (FECs) are analyzed (the results are presented in the form of diagrams). Special attention is paid to FECs made of carbon materials, which, in our opinion, are the most promising direction in the evolution of field-emission electronics. FEC utilization in modern electronic devices is illustrated by several examples. The main sections of the paper are devoted to analyzing the problems and prospects of FECs and field-emission electronics.
Results of experiments aimed at the creation of ion sources employing alloys as materials for field emitters are presented. Using even simple alloys it is possible to obtain ion sources for elements, from which it is difficult or impossible to make emitter directly. Using emitter surface enrichment of some component it is possible to obtain an ion source even if the content of this element is as low as fractions of a percent.
For researches on plasma physics has been designed and constructed the electronic gun with the cold cathode on energy to 300 keV. The gun have the parameters: time width of pulses - 100 ns, current amplitude - 100 A, repetition rate - 100 Hz. The desorption emitter is a set of thin mica and copper plates. Results of the fabrication and testing are reported.
Fringe effects of electric field distribution near the FEA surface in diode configuration are studied by mathematical modelling. Different anode shapes are considered: plane anode and spherical anode. Modelling results of surface electric field distribution are presented. The spherical shape of anode allows higher voltage (and higher field emission current) without destructive arcs risk.
The phenomenological model of the known so-called “low-voltage” field emission phenomenon is offered and advanced. The model is developed on the basis of an original experimental data received in researches of the “field induced” emission properties of a low-dimensional nanoheterostructures.
Created a hardware and software system employing the spatial optimization and parallelization for the simulation of relativistic and non-relativistic electron beams with arbitrary orientation of the external fields. The model is based on the implementation of large-particle method and calculation of space-charge forces by the "particle-particle" with regard of delay.
Ultrathin magnetic films of transition metal silicides are perspective for spintronics. In this work we have studied formation of Fe3Si and Co3Si films on Si(100)2×1 by the solid phase epitaxy. The experiments were performed in ultra-high vacuum using photoelectron spectroscopy with synchrotron radiation. Correlations are found out between changes of the phase composition of synthesized films and their magnetic properties.
Solving the problems associated with the improvement of single-phase earth fault (SPEF) protection devices and SPEF location determination devices on the lines is of practical interest to study the operation of cable current transformers and other sensors in the transients states. The paper discusses the principles of constructing models of current sensors in the environment Matlab.
Pressed oxide cathode with emission coating as a nickel sponge filled with earth metal carbonate with 10×10 cm2 area is described. This cathode consists of four plate 5×5 cm2 which are heated with four separate heaters, each plate and heater are fixed on thin rods to a common platform 10×10 cm2. The design allows to replace plates and increase the number of plates up to the total cathode area 20×20 cm2 and higher.
The investigation of emissive ability, lifetime, structure and component surface composition of scandate cathodes with a matrix of tungsten and of tungsten-rhenium matrix impregnated with barium-calcium aluminate (4: 1: 1 or 6: 1: 2 moles) with 0.5-5 weight nonuniform emission can be explained by formation of crystals up to 100 nm in size consisting mainly of scandium oxide, barium oxide and calcium oxide.
The binding energies of Si 2p, Fe 3p, Co 3p and Mn 3p core-shell electrons have been determined for a number of 3d-metall silicides (Fe3Si, ε-FeSi, β-FeSi2, Co3Si, Co2Si, CoSi, CoSi2, MnSi and MnSi1.7) using high-resolution photoelectron spec-troscopy with synchrotron radiation. The silicides were formed by solid-state epitaxy under identical conditions on Si(100) and Si(111) faces of silicon single crystals.
The given is the review of the basic result of experimental investigations of the electron work function of sodium. It has been shown that (i) existing data are a few and obtained in narrow temperature limits, (ii) electron work function of sodium at negative temperatures is reported in just several papers, (iii) the temperature dependence of electron work function does not reveal any noticeable breaks neither discontinuities in the area of phase transition “solid-liquid”.
Thin films from Ge-S-AgI system with various amount of AgI prepared by pulsed laser deposition and vacuum thermal evaporation method have been studied. The films are analysed with respect to their morphology, structure and roughness. The optical properties are investigated as a function of the composition and preparation method.
Micro Hollow Cathode Discharge (MHCD) arrays, fabricated in silicon with Al2O3 or titanium silicide- coated cathodes, have been investigated for use as high-current, cold-cathode electron sources. When arranged as large arrays, micron-scale MHCD's have the potential to be used as electron-beam sources with current densities up into the A-cm(-2) range. Analysis, simulations and experimental data show that a quantum-mechanical tunneling current through the aluminum oxide cathode coating (when made thin enough) allows the DC operation of a MHCD at modest vacuum using Ar. The high secondary-electron emission and low sputter yield, of Al2O3 leads to increases in the plasma electron density and cathode operating lifetimes, respectively. Preliminary data show a significant increase in current density under identical operating conditions, using the alumina dielectric-coated cathodes as compared with bare-silicon baseline cathodes.
Electron holographic apparatus is intended to obtain and analyze three-dimensional structure of organic and inorganic films, fibers and macromolecules with thickness up to 10 nm. The main units of the apparatus is a compact ultrahigh-vacuum chamber, the sample positioning system, a point coherent source of electrons and system of registration and processing of holographic images. Apparatus control and processing of holographic images using a computer system, for which we developed the appropriate software.
Oligomeric phthalocyanines and metallophthalo-cyanines are under intensive investigation because of their potential application as new photonic and electronic materials. Quantum chemical methods were used to calculate supramolecules, containing metallophthalocyanines for modeling new semiconductor materials and solar cells elements.
