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[en] A ring-shaped electrode with numerous functions has been tested: it provides angular confinement of the electron emission and protects the tip against breakdown; the lifetime of the tip may reach a thousand hours. The qualities of the field-emitted beam are preserved as is shown by the results obtained when a transmission electron microscope was equipped with this device. In spite of their remarkable properties such as high brightness and low energy spread, field-emission sources of electrons have had rather poor commercial success up to now. This can be understood because of the technological problems associated with their use and particularly, with the vacuum requirements. In practice it seems that the real difficulties are to achieve a sufficiently stable and high beam current and to obtain a reasonable cathode lifetime. The technique presented here does not solve all the problems but it is a new approach to a part of the solution. (orig.)
[en] We study the effect of the band structure on the energy distributions of field emitted electrons from AB and ABC graphene multilayers. The characteristic sub-peaks are found to appear for each type of stacking. The experimental discovery of these peaks in field emission experiments from carbon few-layer systems can provide important information about a type of stacking.
[en] Highlights: • Graphite is made from graphite oxide with well-defined basal plane and edges. • The edges have demonstrated inferior field emission performance. • The sparse wrinkles on the basal plane play important roles as emission sites. • The oxygen-containing groups lead to deterioration in field emission performance.
[en] This bibliography, covering the period 1993, includes references related to the following topics: atom probe field ion microscopy (APFIM), field emission (FE), and field ion microscopy (FIM). Technique-oriented studies and applications are included. The references contained in this document were compiled from a variety of sources including computer searches and personal lists of publications. To reduce the length of this document, the references have been reduced to the minimum necessary to locate the articles. The references are listed alphabetically by authors, an Addendum of references missed in previous bibliographies is included
[en] A novel field emission cathode process has been developed to produce cathode arrays with individual emitter structures having gates with <300 nm diameters. Ion tracking lithography was utilized to pattern submicron features, which can be controlled over the range 30-300 nm, and to create self-aligned and nanosized, gated emitter structures. Nanocone emitter tips were deposited into the gate structure using a variation of the Spindt process. Field emitter arrays having ∼300 nm gate diameters and an emitter density of 108/cm2 exhibited a current density of 4 mA/cm2 for a 45 V gate bias. This ion tracking lithographic approach is suitable and scalable for large flat panel video displays and appears to be commercially viable. (c) 2000 American Vacuum Society
[en] Arrays of gold nanocones have been fabricated by the nanotransfer printing (nTP) method and we have utilized these nanocones for field emission. By the nature of the printing, any shape of metal structure can be fabricated only at desired locations and a step-and-repeat process, which enables large-area fabrication, is possible. We demonstrate step-and-repeat printing with gold nanocone patterns occupying an area of 9 mm x 8 mm
[en] The problem of determining the emission current as a function of voltage, radius of the micropoint curvature, and the distance between the micropoint and a conducting plane is considered on the basis of the theoretical method developed for determining the electric field in the vicinity of a paraboloidal micropoint near a plane metal surface. The universal current–voltage characteristics for a copper micropoint, which are considered for various distances between the micropoint and the plane, can be used for obtaining quantitative estimates of currents in various physics problems.
[en] Cathodes made of thin-film field emission arrays (FEA) have the advantages of high current density, pulsed emission, and low bias voltage operation. The authors have developed a technology to fabricate knife-edge field emission cathodes on (110) silicon wafers. The emitter geometry is optimized for efficient modulation at high frequency. Cathode fabrication progress and preliminary analysis of their applications in RF power sources are presented
[en] A gas permeable electrode is arranged to project into an evacuated space with the vacuum side of the electrode coated with a gas impervious material except at the tip of the electrode. The other end of the electrode is exposed to an ionizable gas that is caused to diffuse through the electrode and be ionized at the tip of the electrode on the high vacuum side by an electrical field created between the gas permeable electrode and an extraction electrode in the high vacuum space