Experimental Derivation of Resonant Tunneling Transit Time Using a Coupled-Quantum-Well Base Transistor

Abstract
We derive the base transit time in a GaAs/AlAs coupled-quantum-well (CQW) base transistor through its high-frequency characteristics. The estimated time should be equivalent to the resonant tunneling transit time, since the collector current in this transistor is the resonant tunneling current flowing through the CQW base and is controlled by the CQW's potential. It is found that the experimentally derived time for 2-nm AlAs barriers (3.2±0.8 ps) agrees reasonably well with the theoretically predicted one.