Open AccessLight‐Driven WSe 2 ‐ZnO Junction Field‐Effect Transistors for High‐Performance Photodetection
Author(s) -
Guo Nan,
Xiao Lin,
Gong Fan,
Luo Man,
Wang Fang,
Jia Yi,
Chang Huicong,
Liu Junku,
Li Qing,
Wu Yang,
Wang Yang,
Shan Chongxin,
Xu Yang,
Zhou Peng,
Hu Weida
Publication year - 2020
Publication title -
advanced science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.388
H-Index - 100
ISSN - 2198-3844
DOI - 10.1002/advs.201901637
Subject(s) - responsivity , materials science , optoelectronics , photodetection , photodetector , nanosheet , response time , transistor , nanotechnology , voltage , computer science , physics , computer graphics (images) , quantum mechanics
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 WSe 2 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 WSe 2 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 × 10 3 A W −1 with a gain of ≈10 4 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.