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Carbon nanotubes and fibers are studied with the help of an electron projector and dispersion field-emitted energy analyzer. Probe current-voltage characteristics of samples are exhibited wave-like modulation caused by periodic variations in field-emitted electron energy spectra observed with increasing emission voltage. The explanation relies on the model of Young's interference from two coherent...
In this paper we present the method to produce the multibeam field-emission structure with cylindrical projections made from glassy carbon and coated with thin film of carbon nanotubes. The design of the 7-beam cathode-gate unit consisting of a flat field emission cathode with metal film gate on insulating substrate and 19-beam field emission electron gun with beam compression is performed. It is...
For the analysis of CNT based field emitters a precise calculation of effective emission area is quite important. However, its calculation still involves a lot of uncertainty. Some work was done towards calculating the effective emission area by simulating a single tip CNT cathode using CST Particle Studio. In the model developed, the hemispherical CNT tip was divided into several areas. Electron...
The advantages of argon-ion-irradiated reticulated vitreous carbon (RVC) as a cold-cathode electron source are investigated in the context of a high current density, medium energy, low energy spread, high brightness electron gun.
Field emission cathodes have been a research topic for many decades, with recent interest centering on carbon nanotube (CNT) and carbon fiber structures. These cathodes may well prove useful for a variety of applications, ranging from compact millimeter and THz vacuum electronic devices (VEDs), flat panel displays, and compact x-ray sources. In this presentation we describe experiments performed by...
Using the tunneling effect under high electric field, field emission cold cathode could obtain an emission current which is large enough. In this paper, we reported the large field-emission from CNTs and ZnO tetrapods composited field emitters. Screen-printing method is used in our experiment and more than 15 mA field-emission current is obtained with 0.5 mm gap.
High power terahertz (THz) sources and amplifiers hold the potential to greatly improve remote sensing and high bandwidth communication. To enable these applications, a Traveling Wave Tube (TWT) operating at 0.22 THz and a multi-cathode Field Emission (FE) electron gun are developed and characterized using a Particle-in-Cell simulation. Three candidate high current density cathode materials, Halfnium...
The field-emission cathode has potential application in the field emission display panels, high frequency amplifiers, X-ray sources, cathodoluminescent light sources. In a field-emission display device, the field-emission has to be modulated sensitively. Therefore, a few kinds of field-emission triode, such as normal-gate, under-gate and lateral-gate have been proposed. To simplify the fabrication...
In this work, a carbon nanotube-based microtriode has been realized. It is characterized by an emission area covered with carbon nanotubes and an extracting grid integrated on the same substrate. The two are separated with an insulating layer. The DC characteristics were measured both in a diode and in a triode configuration.
Summary form only given. We present the development of a plasma-enhanced chemical vapor deposition (PECVD) system for deposition of multi-walled, vertically aligned Carbon Nano-Tubes (CNT) as cathode field emitter sites in a large (1000 x 1000), 1 cm2 area array. The CNT deposition is compatible with the use of Si wafers containing the individual emitter site ballasts in the form of Si n-type JFETs...
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