Nano Research

, Volume 11, Issue 2, pp 722–730 | Cite as

High-performance multilayer WSe2 field-effect transistors with carrier type control

  • Pushpa Raj Pudasaini
  • Akinola Oyedele
  • Cheng Zhang
  • Michael G. Stanford
  • Nicholas Cross
  • Anthony T. Wong
  • Anna N. Hoffman
  • Kai Xiao
  • Gerd Duscher
  • David G. Mandrus
  • Thomas Z. Ward
  • Philip D. RackEmail author
Research Article


In this study, high-performance multilayer WSe2 field-effect transistor (FET) devices with carrier type control are demonstrated via thickness modulation and a remote oxygen plasma surface treatment. Carrier type control in multilayer WSe2 FET devices with Cr/Au contacts is initially demonstrated by modulating the WSe2 thickness. The carrier type evolves with increasing WSe2 channel thickness, being p-type, ambipolar, and n-type at thicknesses <3, ∼4, and >5 nm, respectively. The thickness-dependent carrier type is attributed to changes in the bandgap of WSe2 as a function of the thickness and the carrier band offsets relative to the metal contacts. Furthermore, we present a strong hole carrier doping effect via remote oxygen plasma treatment. It non-degenerately converts n-type characteristics into p-type and enhances field-effect hole mobility by three orders of magnitude. This work demonstrates progress towards the realization of high-performance multilayer WSe2 FETs with carrier type control, potentially extendable to other transition metal dichalcogenides, for future electronic and optoelectronic applications.


transition metal dichalcogenide field-effect transistors carrier control plasma treatment carrier mobility 


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P. D. R. and M. G. S. acknowledge support by U.S. Department of Energy (DOE) under Grant No. DOE DE-SC0002136. P. R. P. and D. G. M. acknowledge funding by the Gordon and Betty Moore Foundation’s EPiQS Initiative through Grant GBMF4416. T. Z. W. acknowledges support U.S. Department of Energy (DOE), Office of Basic Energy Sciences (BES), Materials Sciences and Engineering Division. A. T. W. acknowledges support by Laboratory Directed Research and Development Program of Oak Ridge National Laboratory, managed by UT-Battelle, LLC, for the U.S. Department of Energy. N. C. acknowledges support by National Science Foundation (NSF) (No. DMR- 1410940). The authors acknowledge that the device synthesis and Raman mapping were conducted at the Center for Nanophase Materials Sciences, which is a DOE Office of Science User Facility.

Supplementary material

12274_2017_1681_MOESM1_ESM.pdf (1.5 mb)
High-performance multilayer WSe2 field-effect transistors with carrier type control


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Copyright information

© Tsinghua University Press and Springer-Verlag GmbH Germany 2018

Authors and Affiliations

  • Pushpa Raj Pudasaini
    • 1
    • 2
  • Akinola Oyedele
    • 2
    • 3
  • Cheng Zhang
    • 1
    • 2
  • Michael G. Stanford
    • 1
  • Nicholas Cross
    • 1
  • Anthony T. Wong
    • 1
  • Anna N. Hoffman
    • 1
  • Kai Xiao
    • 2
  • Gerd Duscher
    • 1
    • 4
  • David G. Mandrus
    • 1
    • 4
  • Thomas Z. Ward
    • 4
  • Philip D. Rack
    • 1
    • 2
    Email author
  1. 1.Department of Materials Science and EngineeringUniversity of TennesseeKnoxvilleUSA
  2. 2.Center for Nanophase Materials SciencesOak Ridge National LaboratoryOak RidgeUSA
  3. 3.Bredesen Center for Interdisciplinary Research and Graduate EducationUniversity of TennesseeKnoxvilleUSA
  4. 4.Materials Science and Technology DivisionOak Ridge National LaboratoryOak RidgeUSA

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