Well-aligned b-phase W~100! nanorods having square-base pyramidal apexes were grown on oxidized Si~100! substrate using glancing angle deposition technique with substrate rotation. The field emission characteristics of nanorods were measured using scanning tunneling microscope ~STM! tip as an extraction anode. A highly confined emission current of about 23 mA was obtained at a low extraction vo...

Behavior of the xenon dispenser hollow cathode is complex, exhibiting high through-anode ion emission, unusual particle energy distributions, and high plume erosion rates. The device may find new application as an ion micro-thruster. A flight-type hollow cathode was characterized using several diagnostic methods. Measurements involved a retarding potential analyzer, quadrupole mass spectrometer...

2014 The pure-hydrogen discharges in surface-plasma sources with a semiplanotron electrode configuration are described. In short pulse (10-3 s) mode the extracted Hemission density was up to 1.1 A/cm2 at cathode discharge current density 60 A/cm2. The multi-slit short pulse extraction delivered the Houtput with current of up to 1 A. In the long pulse (0.6 s) mode the Hyield was 0.15 A at discha...

A nanolaboratory—a prototype nanomanufacturing system—is presented, which is composed with a nanorobotic manipulation system with 4 units and 16 degrees-offreedom (DOFs), a nano fabrication system based on electron-beam-induced deposition (EBID) with an internal or external precursor evaporation reservoir equipped with a thermal field emission electron source or a nanotube cold cathode, and a r...

Principle of electroluminescence The light emission in the presented OLED is based on the formation of electron-hole-pairs within conjugated polymers with semiconducting properties. Therefore a suitable polymer like PPV (fig. 1) has to be placed between a transparent anode and a metallic cathode (fig. 2). By application of an electric voltage electrons (on the cathode side) and holes (on the an...

This work is devoted to the study of the electrical characteristics of microhollow cathode discharges (MHCD) at moderate to high pressure in argon and air for different geometries. High-pressure glow discharges can be operated in MHCD devices with μm electrode spacing. Experiments have been performed to determine the so-called Paschen curves, i.e. the dependence of the breakdown voltage on the ...

Femtosecond ultrabright electron sources with spatially structured emission are an enabling technology for free-electron lasers, compact coherent X-ray sources, electron diffractive imaging, and attosecond science. In this work, we report the design, modeling, fabrication, and experimental characterization of a novel ultrafast optical field emission cathode comprised of a large (>100,000 tips),...

Vertically aligned carbon nanofibers ~VACNFs! are extremely promising cathode materials for microfabricated field emission devices, due to their low threshold field to initiate electron emission, inherent stability, and ruggedness, and relative ease of fabrication at moderate growth temperatures. We report on a process for fabricating gated cathode structures that uses a single in situ grown ca...