Analog Circuit Applications based on Ambipolar Graphene/MoTe2 Vertical Transistors

TL;DR

This paper introduces a graphene/MoTe2 vertical transistor with ambipolar behavior that overcomes previous limitations, enabling new analog circuit applications like amplifiers and frequency doublers for telecommunications.

Contribution

The study presents a novel ambipolar graphene/MoTe2 vdW vertical transistor with gate-tunable barriers, demonstrating practical analog circuit functionalities.

Findings

Achieved ambipolar transfer characteristics in the transistor.

Demonstrated output polarity controllable amplifier.

Realized a frequency doubler using the device.

Abstract

The current integrated circuit (IC) technology based on conventional MOS-FET (metal-oxide-semiconductor field-effect transistor) is approaching the limit of miniaturization with increasing demand on energy. Several analog circuit applications based on graphene FETs have been demonstrated with less components comparing to the conventional technology. However, low on/off current ratio caused by the semimetal nature of graphene has severely hindered its practical applications. Here we report a graphene/MoTe2 van der Waals (vdW) vertical transistor with V-shaped ambipolar field effect transfer characteristics to overcome this challenge. Investigations on temperature dependence of transport properties reveal that gate tunable asymmetric barriers of the devices are account for the ambipolar behaviors. Furthermore, to demonstrate the analog circuit applications of such vdW vertical transistors, we successfully realized output polarity controllable (OPC) amplifier and frequency doubler. These results enable vdW heterojunction based electronic devices to open up new possibilities for wide perspective in telecommunication field.