Open AccessSelective Electron Beam Patterning of Oxygen‐Doped WSe 2 for Seamless Lateral Junction Transistors
Author(s) -
Ngo Tien Dat,
Choi Min Sup,
Lee Myeongjin,
Ali Fida,
Hassan Yasir,
Ali Nasir,
Liu Song,
Lee Changgu,
Hone James,
Yoo Won Jong
Publication year - 2022
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.202202465
Subject(s) - materials science , transistor , doping , optoelectronics , oxygen , cathode ray , electron beam induced current , nanotechnology , electron , chemistry , electrical engineering , silicon , physics , engineering , organic chemistry , quantum mechanics , voltage
Surface charge transfer doping (SCTD) using oxygen plasma to form a p‐type dopant oxide layer on transition metal dichalcogenide (TMDs) is a promising doping technique for 2D TMDs field‐effect transistors (FETs). However, patternability of SCTD is a key challenge to effectively switch FETs. Herein, a simple method to selectively pattern degenerately p‐type (p + )‐doped WSe 2 FETs via electron beam (e‐beam) irradiation is reported. The effect of the selective e‐beam irradiation is confirmed by the gate‐tunable optical responses of seamless lateral p + –p diodes. The OFF state of the devices by inducing trapped charges via selective e‐beam irradiation onto a desired channel area in p + ‐doped WSe 2 , which is in sharp contrast to globally p + ‐doped WSe 2 FETs, is realized. Selective e‐beam irradiation of the PMMA‐passivated p + ‐WSe 2 enables accurate control of the threshold voltage ( V th ) of WSe 2 devices by varying the pattern size and e‐beam dose, while preserving the low contact resistance. By utilizing hBN as the gate dielectric, high‐performance WSe 2 p‐FETs with a saturation current of −280 µA µm −1 and on/off ratio of 10 9 are achieved. This study's technique demonstrates a facile approach to obtain high‐performance TMD p‐FETs by e‐beam irradiation, enabling efficient switching and patternability toward various junction devices.