INTEGRATION OF RESONANT-TUNNELING TRANSISTORS AND HOT-ELECTRON TRANSISTORS

We have integrated a tunneling hot-electron transfer amplifier (THETA) and a novel resonant-tunneling hot-electron transfer amplifier (RTHET A) within a single epitaxial growth. At room temperature, the THETA ex hibits a common-emitter current gain of greater than six and a voltage swing of 800 mV when measured in an inverter configuration. The RTHET A exhibits similar common-emitter current gain and a four-state voltag e transfer characteristic with an output voltage swing of 1 V. In cont rast to the resonant-tunneling hot-electron transistor (RHET), the RTH ETA exhibits current gain both before and after the resonant peak volt age. From on-wafer S-parameter measurements, the current-gain cut-off frequency (f(T)) and the maximum frequency of oscillation (f(max)) for both transistors are approximately 20 GHz and 9 GHz, respectively.