Multi-emitter field ion source based on a nanostructural carbon material

THE INVESTIGATIONS OF A PECULIARITIES OF PYROCARBON GAS PHASE DENSIFICATION OF POWDERS OF THE CATALYTIC CARBON FORMATIONS (CCFs), OBTAINED ON NICKEL

“…In the National Science Center Kharkov Institute of Physics and Technology (NSC KIPT) the first experiments on the synthesis of SWNTs by the CVD method were carried out in 1982-1987 [5], at a gas-phase installation "AGAT-1.6". Later on, the numerous studies of the methods of obtaining, properties and areas of practical application of SWNTs and CNM, based on them, were carried out on the installations AGAT-1.6, AGAT-2.0, AGAT-3.2 [6][7][8][9]. Almost all SWNTs described in the literature are covered at both ends by catalyst and CNM particles.…”

High-field formation of multipoint field-electron emitters

“…This interest is primarily due to the possibility of using these emitters as active ele ments in various ion and electro optical devices [1][2][3][4][5]. There is a general tendency toward the develop ment of technology for obtaining emitters operating at possibly low voltages, which is mostly ensured by reducing the radii of emitting points down to a nanometer level.…”

“…The main difficulties encountered in the implementation of these sources are related to the nonuniformity of emis sion [6]. Because of the mutual local screening, the average current per emitter decreases with an increase in their number so that the total emission current is not proportional to this number in the array.The existing high field methods used for decreas ing the dispersion of local field factors in multipoint emitter arrays are based on self consistent variation of the curvature radius at the point vertex depending on the mutual screening factor [5]. However, the effi ciency of these methods is significantly limited by the probability of emitter fracture and electric breakdown in the course of field evaporation [7].…”

“…The existing high field methods used for decreas ing the dispersion of local field factors in multipoint emitter arrays are based on self consistent variation of the curvature radius at the point vertex depending on the mutual screening factor [5]. However, the effi ciency of these methods is significantly limited by the probability of emitter fracture and electric breakdown in the course of field evaporation [7].…”

“…In order to reduce the variance of the local field enhancement factors and form an atomically smooth surface of emitters, we have used the method of low temperature field evaporation [5] based on the expo nential dependence of the rate of material evaporation from the emitter point tip on the electric field strength. The local field enhancement factors in multipoint emitters were leveled by increasing the applied voltage up to a level that ensured attainment of the evaporat ing field strength at the emitter point tips with the maximum radii of curvature.…”