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Title: Spiral growth of few-layer MoS{sub 2} by chemical vapor deposition

Abstract

Growth spirals exhibit appealing properties due to a preferred layer stacking and lack of inversion symmetry. Here, we report spiral growth of MoS{sub 2} during chemical vapor deposition on SiO{sub 2}/Si and epitaxial graphene/SiC substrates, and their physical and electronic properties. We determine the layer-dependence of the MoS{sub 2} bandgap, ranging from 2.4 eV for the monolayer to a constant of 1.3 eV beyond the fifth layer. We further observe that spirals predominantly initiate at the step edges of the SiC substrate, based on which we propose a growth mechanism driven by screw dislocation created by the coalescence of two growth fronts at steps.

Authors:
; ; ;  [1];  [2]
  1. Department of Physics, University of Wisconsin, Milwaukee, Wisconsin 53211 (United States)
  2. Naval Research Laboratory, Washington, DC 20375 (United States)
Publication Date:
OSTI Identifier:
22594320
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 109; Journal Issue: 5; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; CHEMICAL VAPOR DEPOSITION; COALESCENCE; EPITAXY; GRAPHENE; LAYERS; MOLYBDENUM SULFIDES; SCREW DISLOCATIONS; SILICA; SILICON CARBIDES; SILICON OXIDES; SUBSTRATES; SYMMETRY

Citation Formats

Dong, X., Yan, C., Tomer, D., Li, L., E-mail: lianli@uwm.edu, and Li, C. H. Spiral growth of few-layer MoS{sub 2} by chemical vapor deposition. United States: N. p., 2016. Web. doi:10.1063/1.4960583.
Dong, X., Yan, C., Tomer, D., Li, L., E-mail: lianli@uwm.edu, & Li, C. H. Spiral growth of few-layer MoS{sub 2} by chemical vapor deposition. United States. doi:10.1063/1.4960583.
Dong, X., Yan, C., Tomer, D., Li, L., E-mail: lianli@uwm.edu, and Li, C. H. 2016. "Spiral growth of few-layer MoS{sub 2} by chemical vapor deposition". United States. doi:10.1063/1.4960583.
@article{osti_22594320,
title = {Spiral growth of few-layer MoS{sub 2} by chemical vapor deposition},
author = {Dong, X. and Yan, C. and Tomer, D. and Li, L., E-mail: lianli@uwm.edu and Li, C. H.},
abstractNote = {Growth spirals exhibit appealing properties due to a preferred layer stacking and lack of inversion symmetry. Here, we report spiral growth of MoS{sub 2} during chemical vapor deposition on SiO{sub 2}/Si and epitaxial graphene/SiC substrates, and their physical and electronic properties. We determine the layer-dependence of the MoS{sub 2} bandgap, ranging from 2.4 eV for the monolayer to a constant of 1.3 eV beyond the fifth layer. We further observe that spirals predominantly initiate at the step edges of the SiC substrate, based on which we propose a growth mechanism driven by screw dislocation created by the coalescence of two growth fronts at steps.},
doi = {10.1063/1.4960583},
journal = {Applied Physics Letters},
number = 5,
volume = 109,
place = {United States},
year = 2016,
month = 8
}
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