Radiation-Hard Vacuum Field Emission Triode Using a Diamond Microtip Cathode

Vacuum microelectronics will allow production of a new class of devices with distinct advantages over solid state electronic devices in radiation tolerance, high temperature operation, compactness, and high specific power and efficiency. Devices like vacuum field emission transistors (VFETs) have the advantages of vacuum tubes, can be size compatible to silicon microelectronic technology, and utilize field-electron emission. Present field emission cathodes suffer from many problems including lack of emission uniformity and reproducibility. The relatively high work function of the emissive material, capacitance of the device, and space charge effects also adversely effect device performance. Further development of field emission cathodes is the key technology for improved performance of VFETs and other such devices.Systems & Processes Engineering Corporation (SPEC) proposes to develop a VFET using a novel diamond microtip array cathode for improved performance. This cathode has the advantages of metal microtip field emission arrays while eliminating many of the problems associated with metal tips. In Phase I, SPEC will construct and test a "bench top" VFET using the diamond microtip cathodes and compare performance with "standard" field emission arrays and FETs. In Phase II, we will develop process technology to integrate VFETs into standard microelectronic processes.