Advanced Multifunctional Field Effect Devices Using Common Gate for Both 2D Transition‐Metal Dichalcogenide and InGaZnO Channels

Abstract

AbstractVarious functions are introduced from a unique field‐effect device structure which combines or merges transition metal dichalcogenide (TMD) and InGaZnO (IGZO) channels together on one common gate: multivalue field effect transistors (FETs), photodetecting devices, and signal frequency doublers. Judging by the individual transfer characteristics of two FET devices, the n‐IGZO FET always shows higher drain current and more positive‐side turn‐on voltage than those of n‐TMD channel FETs. As a result, a combined transfer characteristic presents two‐step drain current levels, so that their load‐resistance inverter might demonstrate three value output voltage signals. Those ternary value inverter devices with n‐IGZO/n‐ReSe2 or n‐IGZO/n‐WSe2 combination also operate as a photodetector, responding to visible/near infrared (IR) photons with a fast photodynamics of 30 ms rising/falling time. The most interesting is the ambipolar device achieved from n‐IGZO FET/p‐MoTe2 FET combination circuit. The ambipolar device circuit operates as an alternating current (AC) signal frequency doubler and demonstrates twofold organic light emitting diode blinking in one AC period. This unprecedented technique for the multifunctional field effect TMD devices incorporating n‐IGZO FETs will open a new path toward future electronics.