Materials development and current transport in vacuum microelectronic devices

A simple vacuum diode structure has been fabricated using standard microelectronic processing and the electron transport has been investigated. Tungsten and tungsten-carbon thin films have been evaluated and the work function of the tungsten-carbon emitter material was determined to be /spl sim/3.6 eV. A sharpened emitter structure was also fabricated which had a significantly lower turn-on field due to a geometric enhancement in the emitter tip. The electron transport was found to conduct along the surface of the device, which was attributed to dielectric loading of the underlying SiO/sub 2/ layer. Other contributions which affect the electron trajectory were suggested such as electron-electron Coulomb repulsion as well as dynamic surface charging.