Large photoelectric-gating effect of two-dimensional van-der-Waals organic/tungsten diselenide heterointerface

Abstract

Photo-or photoelectric-gating modulation is a promising strategy for high-performance photodetectors, which amplifies photoresponsivity by long-lived trapped charges at the interface. However, the performance is normally limited by the uncontrollable trapping process. Here, we develop a large photoelectric-gating, which enhances interfacial charge trapping process by a van-der-Waals interface with an electric-gating tunable energy barrier in the band alignment. By synergy of photo-gating and electric-gating effects, responsivity and detectivity of 1,4-bis(4-methylstyryl)benzene/tungsten diselenide (WSe 2) increase by 25-fold and 3-fold to 3.6 × 10 6 A/W and 8.6 × 10 14 Jones. High-quality two-dimensional van-der-Waals interface is of great importance. Sufficient supply of gas-phase molecules in physical vapor deposition is pivotal to obtain such interface between organic crystal and WSe 2. As an application, an electric-gating switchable photodetector has been developed, showing great potential of this strategy not only in high-performance photodetectors but also in new photoelectrical devices.

Photodetectors of 2D Materials from Ultraviolet to Terahertz Waves

“…a) Reproduced under the terms of the CC‐BY Creative Commons Attribution 4.0 International license. [ 56 ] Copyright 2018, The Authors, published by Springer Nature. b) Reproduced under the terms of the CC‐BY Creative Commons Attribution 4.0 International license.…”

“…However, the response time was on the order of tens of milliseconds. Cai et al [56] found that sufficient supply of gas-phase molecules in PVD was pivotal to obtain high-quality 2D epitaxial van-der-Waals interface of 1,4-bis(4-methylstyryl)benzene (p-MSB)/WSe 2 (Figure 7a). p-MSB/WSe 2 had an electric-gating tunable barrier at the interface, which could effectively modulate the interface charge trapping process by the gate voltage V g .…”

“…According to Equation ( 16), we know that the substrate will reduce the absorption of the 2D material, which may reduce the performance of the photodetectors. At present, the basis of [56] Copyright 2018, The Authors, published by Springer Nature. b) Reproduced under the terms of the CC-BY Creative Commons Attribution 4.0 International license.…”

“…Hybrid devices made of 2D materials and other materials: a) p-MSB/WSe 2 FET; b) graphene/Ti 2 O 3 photodetector; c) graphene/Bi 2 Te 3 nanowires detector; d) PtSe 2 /Si nanowire array heterostructure; e) schematic of the P(VDF-TrFE)/MoS 2 photodetector located on a polyimide substrate; f) QD/graphene hybrid phototransistors. a) Reproduced under the terms of the CC-BY Creative Commons Attribution 4.0 International license [56]. Copyright 2018, The Authors, published by Springer Nature.…”

Two‐Terminal Multibit Optical Memory via van der Waals Heterostructure

“…[17,18] These 2D vdWs materials and their hybrids are considered to be an ideal platform for nonvolatile optical memory owing to their strong light-matter interactions [19][20][21] and significant photogenerated charge trapping derived from their very large surface-to-volume ratio. [22][23][24] In addition, the mechanical strength and atomic thickness of 2D vdWs materials allow for device miniaturization in flexible and wearable optoelectronics. [25][26][27] The demonstration of 2D vdWs materials-based optical memory in the FETs of few-layer copper indium selenide (CuIn 7 Se 11 ) has been reported [14] along with hybrids of graphene/MoS 2 [5] on a silicon substrate.…”