A New Resonant Tunneling Logic Gate Employing Monostable-Bistable Transition

This letter describes a new resonant tunneling logic gate. The concept of the proposed gate has two features: 1) to employ the monostable-to-bistable transition of a circuit consisting of two N-type negative differential resistance (NDR) devices connected serially, and 2) to drive the logic gate by oscillating the bias voltage to produce the transition. This mode of operation has a significant advantage in that a large number of fanouts is possible without sacrificing the high-speed operation. Serially connected resonant tunneling field effect transistors having p+-junction gates were fabricated to test the above operation principle. The inverter operation of the proposed logic gate has been successfully achieved at room temperature.