Nanoscale doping heterogeneity in few-layer WSe2 exfoliated onto noble metals revealed by correlated SPM and TERS imaging

Deep Jariwala, Andrey Krayev, Joeson Wong, A. Edward Robinson, Michelle C. Sherrott, Shuo Wang, Gang-yu Liu, Mauricio Terrones, Harry A. Atwater

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

While extensive research effort has been devoted to the study of the 2D semiconductor-insulator interfaces in transition metal dichalcogenides (TMDCs), there is little knowledge about the electronic quality of the semiconductor-metal interface in the atomically thin limit. Here, we present the first correlated nanoscale mapping of the interface of atomically thin WSe2 with noble metals using co-localized scanning probe microscopy and tip-enhanced optical spectroscopy (TEOS), such as tip-enhanced Raman spectroscopy (TERS). Nanoscale maps of the topography, surface potential, Raman spectra, and the photocurrent amplitude of the WSe2/metal interfaces reveal striking results. Specifically, correlations between surface potential, resonant Raman signatures and photocurrents that indicate the presence of inhomogeneities within interfacial electronic properties, which we attribute to variations in the local doping of the WSe2 likely caused by intrinsic compositional fluctuations or defects. Our results suggest that local electrostatic variations at a lateral scale of 10-100 nm are present even in the highest quality of TMDC crystals and must be considered towards understanding of all interfacial phenomena, particularly in device applications that rely on the buried metal-semiconductor junction interface.

Original languageEnglish (US)
Article number035003
Journal2D Materials
Volume5
Issue number3
DOIs
StatePublished - Apr 10 2018

Fingerprint

Precious metals
noble metals
Raman spectroscopy
Metals
Doping (additives)
Surface potential
Photocurrents
Imaging techniques
Transition metals
Semiconductor junctions
Semiconductor materials
Scanning probe microscopy
photocurrents
Electronic properties
Topography
transition metals
Raman scattering
Electrostatics
metals
metal crystals

Keywords

  • metal-semiconductor contact
  • photocurrent
  • scanning probe microscopy
  • surface potential mapping
  • tip-enhanced Raman spectroscopy
  • transition metal dichalcogenides
  • tungsten diselenide

ASJC Scopus subject areas

  • Chemistry(all)
  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering

Cite this

Jariwala, D., Krayev, A., Wong, J., Robinson, A. E., Sherrott, M. C., Wang, S., ... Atwater, H. A. (2018). Nanoscale doping heterogeneity in few-layer WSe2 exfoliated onto noble metals revealed by correlated SPM and TERS imaging. 2D Materials, 5(3), [035003]. https://doi.org/10.1088/2053-1583/aab7bc

Nanoscale doping heterogeneity in few-layer WSe2 exfoliated onto noble metals revealed by correlated SPM and TERS imaging. / Jariwala, Deep; Krayev, Andrey; Wong, Joeson; Robinson, A. Edward; Sherrott, Michelle C.; Wang, Shuo; Liu, Gang-yu; Terrones, Mauricio; Atwater, Harry A.

In: 2D Materials, Vol. 5, No. 3, 035003, 10.04.2018.

Research output: Contribution to journalArticle

Jariwala, D, Krayev, A, Wong, J, Robinson, AE, Sherrott, MC, Wang, S, Liu, G, Terrones, M & Atwater, HA 2018, 'Nanoscale doping heterogeneity in few-layer WSe2 exfoliated onto noble metals revealed by correlated SPM and TERS imaging', 2D Materials, vol. 5, no. 3, 035003. https://doi.org/10.1088/2053-1583/aab7bc
Jariwala, Deep ; Krayev, Andrey ; Wong, Joeson ; Robinson, A. Edward ; Sherrott, Michelle C. ; Wang, Shuo ; Liu, Gang-yu ; Terrones, Mauricio ; Atwater, Harry A. / Nanoscale doping heterogeneity in few-layer WSe2 exfoliated onto noble metals revealed by correlated SPM and TERS imaging. In: 2D Materials. 2018 ; Vol. 5, No. 3.
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