Multifunctional anti-ambipolar p-n junction based on MoTe2/MoS2 heterostructure

Abstract

The discovery of atomically thin two-dimensional materials enables building numerous van der Waals heterostructures with original and promising properties for potential electronic and optoelectronic applications. Among them, the antiambipolar characteristic is one of the most appealing ones, which refers to the inverse “V” shape of the transfer curve of the heterojunction. As a result, it is expected to implement various important logic functions, such as double-frequency and multivalue. In this work, we modulated an ambipolar MoTe2/MoS2 heterojunction to show prominent antiambipolar behavior by simply annealing the device at elevated temperature. The on-off ratio and on-state current of the antiambipolar characteristic can be tuned as large as 106 and approximately microamperes, respectively, by optimizing the annealing temperature. Furthermore, we preliminarily demonstrated a self-powered photodetector and a ternary inverter based on this device. The photodetector showed a short-current circuit and an open-circuit voltage of 0.4 μA and 7.5 mV, respectively, at incident light intensity of 2.54 mW/cm2, and gate tunable photocurrent ranging from 0 to 380 pA under zero source-drain bias. The ternary inverter can output three distinct values varying on the order of subvolt as the input voltage (gate bias) ranges from −60 V to 60 V.

Polarity‐Switchable and Self‐Driven Photo‐Response Based on Vertically Stacked Type‐III GeSe/SnS2 Heterojunction

“…[ 17–19 ] As a novel NDR‐like device, it can reproducibly implement both positive and negative transconductance in a single heterojunction device, being switched sharply between two operation modes. [ 20–24 ] For example, Hu et al. demonstrated a ternary inverter by using MoTe 2 FET as a load resistor and 2H‐MoTe 2 /MoS 2 p‐n junction as a driver to achieve multi‐valued output function.…”

“…However, up to now, the anti‐ambipolarity is mainly realized in the heterojunctions with type‐II band arrangement. [ 25 ] Moreover, the most combination categories are based on transition metal dichalcogenides vdWs (MoTe 2 ‐MoS 2 , [ 21 ] WSe 2 ‐WS 2 [ 26 ] ). In previous, anti‐ambipolar characteristic is low repeatability and hindered by the traditional substrate (mostly Si/SiO 2 substrate causing large gate voltage region).…”

Reconfigurable Multivalue Logic Functions of a Silicon Ellipsoidal Quantum-Dot Transistor Operating at Room Temperature

“…For instance, negative-differential conductance (NDC) devices and negative-differential transconductance (NDT) transistors, which comprise diverse kinds of materials ( e.g. , biomolecule complexes, − organic materials, − carbon nanotubes, graphene, , van der Waals heterostructures, − oxide composites, , silicon (Si) nanostructures, − etc . ), are typical examples that can realize the MVL computing system beyond modern binary digital technology.…”

Tunable Intermediate-Logic Ternary Circuits based on MoSe2-WSe2 Heterojunction

“…However, previously reported vdW-H-based ternary circuits include: (1) incomplete output voltage swing [25][26][27] and (2) narrow margin for the intermediate-logic state. [28][29][30] These issues must be addressed to make the ternary circuit suitable to practical applications. Therefore, it is necessary to investigate how to implement vdW-H-based logic more systematically.…”