High-current Field Emitter Arrays for Directed Energy Weapons

Field emission electron emitting arrays hold promise for use in high current density electron beam devices and can replace power consuming thermionic emitters. While single emitters can emit currents up to milliamps, large field emitter arrays are limited in total current due to non-uniformity and resulting instability problems. Solutions to these problems have been attempted using current limiting devices, including a field effect transistor (FET) for each emitter. This is a promising approach but so far has only been used for small total currents. Based on previous work ISSI in cooperation with the University of Southern California (USC) proposes to further develop both experimentally and by modeling whole arrays existing concepts and devices to meet the required total current. The work will be based on the successful demonstration of the fabrication of field effect transistor arrays combined with carbon nanotube array field emitters by USC.