Back to Search
Start Over
Substrate induced tuning of compressive strain and phonon modes in large area MoS 2 and WS 2 van der Waals epitaxial thin films
- Source :
- Journal of Crystal Growth. 470:51-57
- Publication Year :
- 2017
- Publisher :
- Elsevier BV, 2017.
-
Abstract
- Large area MoS2 and WS2 van der Waals epitaxial thin films with control over number of layers including monolayer is grown by pulsed laser deposition utilizing slower growth kinetics. The films grown on c-plane sapphire show stiffening of A(1g) and E-2g(1) phonon modes with decreasing number of layers for both MoS2 and WS2. The observed stiffening translate into the compressive strain of 0.52% & 0.53% with accompanying increase in fundamental direct band gap to 1.74 and 1.68 eV for monolayer MoS2 and WS2, respectively. The strain decays with the number of layers. HRTEM imaging directly reveals the nature of atomic registry of van der Waals layers with the substrate and the associated compressive strain. The results demonstrate a practical route to stabilize and engineer strain for this class of material over large area device fabrication. (C) 2017 Elsevier B.V. All rights reserved.
- Subjects :
- Condensed Matter - Materials Science
Materials science
Condensed matter physics
Phonon
Band gap
Materials Science (cond-mat.mtrl-sci)
FOS: Physical sciences
Nanotechnology
02 engineering and technology
Substrate (electronics)
021001 nanoscience & nanotechnology
Condensed Matter Physics
01 natural sciences
Pulsed laser deposition
Inorganic Chemistry
symbols.namesake
0103 physical sciences
Monolayer
Materials Chemistry
symbols
Direct and indirect band gaps
van der Waals force
010306 general physics
0210 nano-technology
High-resolution transmission electron microscopy
Subjects
Details
- ISSN :
- 00220248
- Volume :
- 470
- Database :
- OpenAIRE
- Journal :
- Journal of Crystal Growth
- Accession number :
- edsair.doi.dedup.....605d4c78615e116d2dc952d5f2786984