High Mobility <i>n</i>-type Field-Effect Transistors Based on WSe<sub>2</sub>/PdSe<sub>2 </sub>Heterostructures

ORAL

Abstract

Recently, group-10 transition metal dichalcogenides (TMDs) such as PtSe2 and PdSe2 have emerged as 2D materials with a theoretically predicted electron mobility significantly higher than that of group-6 TMDs. However the performance of field-effect transistors (FETs) based on few-layer PdSe2 has been limited by the presence of a Schottky barrier at the drain/source contacts. In this work, we utilize a 2D-semiconductor interlayer at the metal/PdSe2 contacts to significantly lower the Schottky barrier. As a result, our FETs based on PdSe2/WSe2 heterostructures exhibit a two-terminal effective mobility exceeding 200 cm2 V-1 s-1 at room temperature and approaching 700 cm2 V-1 s-1 at 77 K, consistent with phonon-limited electron transport. By contrast, the two-terminal effective mobility of FETs based on few-layer PdSe2 (without WSe2) decreases with decreasing temperature, suggesting that the electron transport is limited by the contacts. Our PdSe2/WSe2 heterostructure FET consisting of a trilayer PdSe2 and a bilayer WSe2 concurrently exhibits a high ON/OFF ratio of ~ 107 and significantly enhanced two-terminal electron mobility compared to FETs based on a trilayer PdSe2 or a bilayer WSe2 alone.

*This work was supported by NSF Grant No. DMR-2004445 and Kaskas Scholarship Funds.

–

Presenters

  • Arthur Bowman

    • Wayne State University

Authors

  • Arthur Bowman

    • Wayne State University

  • Kraig J Andrews

    • Wayne State University

  • Amanda Haglund

    • University of Tennessee
    • Materials Science and Engineering, The University of Tennessee

  • David George Mandrus

    • Materials Science and Technology Division, Oak Ridge National Labratory
    • Materials Science and Engineering, University of Tennessee
    • Department of Materials Science and Engineering, University of Tennessee
    • University of Tennessee
    • Department of Materials Science and Engineering, University of Tennessee Knoxville
    • Department of Materials Science & Engineering, University of Tennessee, Knoxville, Tennessee 37996, USA
    • Oakridge National Laboratory
    • Materials Science and Engineering, University of Tennessee, Knoxville
    • Oak Ridge National Laboratory
    • University of Tennessee - Knoxville
    • Materials Science and Technology Division, Oak Ridge National Laboratory
    • Department of Physics, University of Tennessee Knoxville
    • Materials Science and Technology, Oak Ridge National Laboratory
    • Oak Ridge National Laboratory, Materials Science and Technology Division
    • Department of Materials Science, The University of Tennessee
    • University of Tennessee, Knoxville

  • Zhixian Zhou

    • Wayne State University