A proposed state-of-the-art 1-25 GHz, vacuum field emitter triode (FET) distributed amplifier (DA) of 9+or-1 dB maximum gain has been tested in a Touchstone computer simulation. Theoretical analysis reveals that the vacuum FET DA's gain-bandwidth product is limited primarily by microstripline metal interconnect losses and by low device f/sub T/ values, but surprisingly not by the internal device losses. The results suggest that a vacuum FET DA with low loss microstripline interconnect and high device f/sub T/ values is potentially of exceptionally high gain-bandwidth product. An investigation of device enhancement for high-frequency operation compares the relative merits of a lower emitter work function and a greater electric field enhancement factor beta =E/V/sub gc/.<
Published in:
Electron Devices Meeting, 1990. IEDM '90. Technical Digest., International
Date of Conference: 9-12 Dec. 1990