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Tuning the Polarity of MoTe₂ FETs by Varying the Channel Thickness for Gas-Sensing Applications.

ABSTRACT: In this study, electrical characteristics of MoTe₂ field-effect transistors (FETs) are investigated as a function of channel thickness. The conductivity type in FETs, fabricated from exfoliated MoTe₂ crystals, switched from p-type to ambipolar to n-type conduction with increasing MoTe₂ channel thickness from 10.6 nm to 56.7 nm. This change in flake-thickness-dependent conducting behavior of MoTe₂ FETs can be attributed to modulation of the Schottky barrier height and related bandgap alignment. Change in polarity as a function of channel thickness variation is also used for ammonia (NH₃) sensing, which confirms the p- and n-type behavior of MoTe₂ devices.

SUBMITTER: Rani A

PROVIDER: S-EPMC6603731 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature

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Tuning the Polarity of MoTe2 FETs by Varying the Channel Thickness for Gas-Sensing Applications.

Rani Asha A DiCamillo Kyle K Khan Md Ashfaque Hossain MAH Paranjape Makarand M Zaghloul Mona E ME

Sensors (Basel, Switzerland) 20190604 11

In this study, electrical characteristics of MoTe2 field-effect transistors (FETs) are investigated as a function of channel thickness. The conductivity type in FETs, fabricated from exfoliated MoTe2 crystals, switched from p-type to ambipolar to n-type conduction with increasing MoTe2 channel thickness from 10.6 nm to 56.7 nm. This change in flake-thickness-dependent conducting behavior of MoTe2 FETs can be attributed to modulation of the Schottky bar ...[more]

PMID: 31167486

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