Emission of electrons from a patterned negative electron affinity cathode

We have developed a microelectronics process to achieve the negative electron affinity (NEA) effect on the exposed areas of a patterned p/sup ++/-GaAs chip. The process was also extended to fabricate multielectrode NEA cathodes. The ability to selectively emit electrons from small areas can have applications in NEA-based vacuum microelectronic devices, projection e-beam lithography tools, and combinations of bulk devices with vacuum electronic emitters. Such instruments can take advantage of the cold operation, monochromaticity and high brightness of NEA cathodes.<>