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Title: Thickness-dependent electron mobility of single and few-layer MoS{sub 2} thin-film transistors

Abstract

We investigated the dependence of electron mobility on the thickness of MoS{sub 2} nanosheets by fabricating bottom-gate single and few-layer MoS{sub 2} thin-film transistors with SiO{sub 2} gate dielectrics and Au electrodes. All the fabricated MoS{sub 2} transistors showed on/off-current ratio of ∼10{sup 7} and saturated output characteristics without high-k capping layers. As the MoS{sub 2} thickness increased from 1 to 6 layers, the field-effect mobility of the fabricated MoS{sub 2} transistors increased from ∼10 to ∼18 cm{sup 2}V{sup −1}s{sup −1}. The increased subthreshold swing of the fabricated transistors with MoS{sub 2} thickness suggests that the increase of MoS{sub 2} mobility with thickness may be related to the dependence of the contact resistance and the dielectric constant of MoS{sub 2} layer on its thickness.

Authors:
; ; ; ;  [1];  [2]
  1. School of Electrical Engineering, Korea University, Seoul 02841 (Korea, Republic of)
  2. School of Advanced Materials Engineering, Kookmin University, Seoul 02707 (Korea, Republic of)
Publication Date:
OSTI Identifier:
22611531
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Advances; Journal Volume: 6; Journal Issue: 6; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; DIELECTRIC MATERIALS; ELECTRODES; ELECTRON MOBILITY; GOLD; LAYERS; MOLYBDENUM SULFIDES; NANOSTRUCTURES; PERMITTIVITY; SILICON OXIDES; THICKNESS; THIN FILMS; TRANSISTORS

Citation Formats

Kim, Ji Heon, Kim, Tae Ho, Lee, Hyunjea, Park, Young Ran, Lee, Cheol Jin, E-mail: cjlee@korea.ac.kr, and Choi, Woong, E-mail: woongchoi@kookmin.ac.kr. Thickness-dependent electron mobility of single and few-layer MoS{sub 2} thin-film transistors. United States: N. p., 2016. Web. doi:10.1063/1.4953809.
Kim, Ji Heon, Kim, Tae Ho, Lee, Hyunjea, Park, Young Ran, Lee, Cheol Jin, E-mail: cjlee@korea.ac.kr, & Choi, Woong, E-mail: woongchoi@kookmin.ac.kr. Thickness-dependent electron mobility of single and few-layer MoS{sub 2} thin-film transistors. United States. doi:10.1063/1.4953809.
Kim, Ji Heon, Kim, Tae Ho, Lee, Hyunjea, Park, Young Ran, Lee, Cheol Jin, E-mail: cjlee@korea.ac.kr, and Choi, Woong, E-mail: woongchoi@kookmin.ac.kr. 2016. "Thickness-dependent electron mobility of single and few-layer MoS{sub 2} thin-film transistors". United States. doi:10.1063/1.4953809.
@article{osti_22611531,
title = {Thickness-dependent electron mobility of single and few-layer MoS{sub 2} thin-film transistors},
author = {Kim, Ji Heon and Kim, Tae Ho and Lee, Hyunjea and Park, Young Ran and Lee, Cheol Jin, E-mail: cjlee@korea.ac.kr and Choi, Woong, E-mail: woongchoi@kookmin.ac.kr},
abstractNote = {We investigated the dependence of electron mobility on the thickness of MoS{sub 2} nanosheets by fabricating bottom-gate single and few-layer MoS{sub 2} thin-film transistors with SiO{sub 2} gate dielectrics and Au electrodes. All the fabricated MoS{sub 2} transistors showed on/off-current ratio of ∼10{sup 7} and saturated output characteristics without high-k capping layers. As the MoS{sub 2} thickness increased from 1 to 6 layers, the field-effect mobility of the fabricated MoS{sub 2} transistors increased from ∼10 to ∼18 cm{sup 2}V{sup −1}s{sup −1}. The increased subthreshold swing of the fabricated transistors with MoS{sub 2} thickness suggests that the increase of MoS{sub 2} mobility with thickness may be related to the dependence of the contact resistance and the dielectric constant of MoS{sub 2} layer on its thickness.},
doi = {10.1063/1.4953809},
journal = {AIP Advances},
number = 6,
volume = 6,
place = {United States},
year = 2016,
month = 6
}
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