GaAs transferred electron devices and field effect transistors in monolithic integrated circuits

Abstract

Analog-to-digital conversion is being extended to data rates of up to a few giga-samples per second, by advancements in materials, device and process technology. Specific improvements in the material are the result of improved substrate qualification procedures. The primary process improvements include improved annealing and capping for repeatability in ion implantation and selective implantation for reduced contact resistance in ohmic regions. Further, selective ion implant and isolation implants have shown promise for planar processing. TRW has combined the technological developments to fabricate high frequency mesa and planar circuits using transferred electron devices (TED’s) and metal–semiconductor field effect transistors (MESFET’s) as the principal circuit elements.