Novel High Current Switch for Spacecraft Power Bus Control

The proposed semiconductor-insulator-semiconductor ("SIS") is herein defined as a structure consisting of two semiconductor layers separated by an insulator. PTS proposes such a SIS structure as a latching on/off switch consisting of a GaN-AlGaN emitter orcathode and a SiC anode. The GaN cathode will be designed as an efficient electron gun or cathode. The SiC anode will be designed as both an efficient electron receiver as well as a hole emitter. The design will take advantage of the high thermalconductivity of SiC to dissipate the anode heat. The SIS insulator will be a vacuum, gas or solid. Both anode and cathode emitting/receiving surfaces will be designed as a low work function or negative electron affinity emitter. This microminiature vacuumswitch will turn on and off within nanoseconds. The switch will conduct high current, block high voltage, and will accrue the advantages of ballistic charge transfer at operating temperatures approaching 500 degrees Centigrade. The device will be used foraerospace applications and will replace less efficient solid state and spark gap switches. The device will also be useful in pulse power applications with unlimited Di/Dt and blocking voltage.