Phase transition in two-dimensional monolayer (1L)-molybdenum disulfide induced by atomic S-basal plane gliding via synchrotron X-ray monochromatic beam radiation for superior electronic performance
Journal
Materials Today
Journal Volume
84
Start Page
28
End Page
38
ISSN
1369-7021
Date Issued
2025-05
Author(s)
Abstract
Here, we report a novel approach to reduce the channel resistance by inducing a phase transition behavior from 2H to 1T in a monolayer MoS2 (1L-MoS2) by a synchrotron X-ray monochromatic beam (mono-beam) radiation. The effects of the biphase structure by the mono-beam on the 1L-MoS2 film were investigated using Raman spectra, photoluminescence (PL) spectra, scanning tunneling microscopy, and scanning tunneling spectroscopy, respectively. Through material characterization, we identified that the lateral sliding of S-vacancies along the S-plane in the 1L-MoS2 is the key reason for the origin of unidirectional phase transition. The precise phase engineering triggered by the mono-beam radiation process allows the realization of field-effect transistors (FET) with 2X improvement in mobility toward a high on/off ratio (∼108) and a near-ideal subthreshold swing of ∼88 mV per decade. The validity of the phase engineering could be further extended for its application as a memory device, exhibiting a gate tunable conduction modulation behavior and a high resistance ratio of ∼ 102 at a gate bias of 5 V with endurance of ∼100 cycles. Furthermore, an artificial neural network using the synaptic weight update with accuracy of ∼93 % was achieved.
Subjects
Defect engineering
Memtransistor
Sulfur vacancies
Transition metal dichalcogenide
X-ray monochromatic beam (mono-beam) radiation
Publisher
Elsevier BV
Type
journal article