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Title: Low resistance electrical contacts to few-layered MoS 2 by local pressurization
Abstract The performance of electronic and optoelectronic devices is dominated by charge carrier injection through the metal–semiconductor contacts. Therefore, creating low-resistance electrical contacts is one of the most critical challenges in the development of devices based on new materials, particularly in the case of two-dimensional semiconductors. Herein, we report a strategy to reduce the contact resistance of MoS 2 via local pressurization. We fabricated electrical contacts using an atomic force microscopy tip and applied variable pressure ranging from 0 to 25 GPa. By measuring the transverse electronic transport properties, we show that MoS 2 undergoes a reversible semiconducting-metallic transition under pressure. Planar devices in field effect configuration with electrical contacts performed at pressures above ∼15 GPa show up to 30-fold reduced contact resistance and up to 25-fold improved field-effect mobility when compared to those measured at low pressure. Theoretical simulations show that this enhanced performance is due to improved charge injection to the MoS 2 semiconductor channel through the metallic MoS 2 phase obtained by pressurization. Our results suggest a novel strategy for realizing improved contacts to MoS 2 devices by local pressurization and for exploring emergent phenomena under mechano-electric modulation.  more » « less
Award ID(s):
2130552
PAR ID:
10447095
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Date Published:
Journal Name:
2D Materials
Volume:
10
Issue:
2
ISSN:
2053-1583
Page Range / eLocation ID:
021003
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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