Light‐Driven WSe2‐ZnO Junction Field‐Effect Transistors for High‐Performance Photodetection

Abstract Assembling nanomaterials into hybrid structures provides a promising and flexible route to reach ultrahigh responsivity by introducing a trap‐assisted gain (G) mechanism. However, the high‐gain photodetectors benefitting from long carrier lifetime often possess slow response time (t) due to...

Full description

Bibliographic Details
Main Authors: Nan Guo, Lin Xiao, Fan Gong, Man Luo, Fang Wang, Yi Jia, Huicong Chang, Junku Liu, Qing Li, Yang Wu, Yang Wang, Chongxin Shan, Yang Xu, Peng Zhou, Weida Hu
Format: Article
Language:English
Published: Wiley 2020-01-01
Series:Advanced Science
Subjects:
Online Access:https://doi.org/10.1002/advs.201901637
Description
Summary:Abstract Assembling nanomaterials into hybrid structures provides a promising and flexible route to reach ultrahigh responsivity by introducing a trap‐assisted gain (G) mechanism. However, the high‐gain photodetectors benefitting from long carrier lifetime often possess slow response time (t) due to the inherent G–t tradeoff. Here, a light‐driven junction field‐effect transistor (LJFET), consisting of an n‐type ZnO belt as the channel material and a p‐type WSe2 nanosheet as a photoactive gate material, to break the G–t tradeoff through decoupling the gain from carrier lifetime is reported. The photoactive gate material WSe2 under illumination enables a conductive path for externally applied voltage, which modulates the depletion region within the ZnO channel efficiently. The gain and response time are separately determined by the field effect modulation and the switching speed of LJFET. As a result, a high responsivity of 4.83 × 103 A W−1 with a gain of ≈104 and a rapid response time of ≈10 µs are obtained simultaneously. The LJFET architecture offers a new approach to realize high‐gain and fast‐response photodetectors without the G–t tradeoff.
ISSN:2198-3844