High current dc and pulsed field emission from single crystal ZrC[100] emitters mounted in apertures

Summary form only given. We have been working for several years on field emission from transition metal carbides. These studies have covered emission from solid carbide field emitters as well as thin film carbide overcoatings on single tip field emitters and field emitter arrays. These carbide materials have emission properties making them attractive candidates for uses requiring high currents, small spot sizes, and cold cathodes for operation in poor vacuum. Uses might include microwave devices, electron accelerators, free-electron lasers, and other high current applications. We report on field emission studies using [100] oriented ZrC field emitters configured in an extraction or gate aperture. This geometry can allow for efficient confinement and a high brightness beams. Stable high-current emission has been obtained in the 2 mA range dc and pulsed currents as high as 50 mA are demonstrated.