Loading...

Seedless growth of two-dimensional disc-shaped WS2 layers by chemical vapor deposition

Rahmani Taji Boyuk, M.R ; Sharif University of Technology | 2021

367 Viewed
  1. Type of Document: Article
  2. DOI: 10.1016/j.matchemphys.2020.123837
  3. Publisher: Elsevier Ltd , 2021
  4. Abstract:
  5. Chemical processing of two-dimensional (2D) transition metal dichalcogenides has attracted immense attention due to their unique optical, electrical, and catalytic properties. In this paper, we show that under special conditions during seedless chemical vapor deposition (CVD), it is possible to grow large-area 2D WS2 layers with disc-shaped morphology, which has been scarcely reported. Detailed characterizations of the CVD-grown layers by Raman spectroscopy, atomic force microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy have revealed that a gradient in the precursor concentration in the gas phase and strain energy in the deposited hexagonal clusters favor disc-shaped growth of the 2D metal sulfide. The formation of large-area films with few millimeters in the lateral direction is also feasible by the continuation of the process. Herein, barriers against edge diffusion facilitate symmetric growth on the nucleates to develop ultrathin and large-area films. The process is attractive for the fabrication of optoelectronic devices by 2D semiconductor materials. © 2020 Elsevier B.V
  6. Keywords:
  7. Atomic force microscopy ; Chemical industry ; High resolution transmission electron microscopy ; Optoelectronic devices ; Semiconductor devices ; Strain energy ; Sulfur compounds ; Transition metals ; Tungsten compounds ; Ultrathin films ; X ray photoelectron spectroscopy ; Catalytic properties ; Chemical processing ; Chemical vapor depositions (CVD) ; Edge diffusion ; Lateral directions ; Precursor concentration ; Transition metal dichalcogenides ; Two Dimensional (2 D) ; Chemical vapor deposition
  8. Source: Materials Chemistry and Physics ; Volume 257 , 2021 ; 02540584 (ISSN)
  9. URL: https://www.sciencedirect.com/science/article/abs/pii/S0254058420311962