Field-effect transistors and intrinsic mobility in ultra-thin MoSe2 layers

S. Larentis; B. Fallahazad; E. Tutuc

doi:10.1063/1.4768218

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arXiv · 1211.3096

Field-effect transistors and intrinsic mobility in ultra-thin MoSe2 layers

S. Larentis·B. Fallahazad·E. Tutuc

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Abstract

We report the fabrication of back-gated field-effect transistors (FETs) using ultra-thin, mechanically exfoliated MoSe2 flakes. The MoSe2 FETs are n-type and possess a high gate modulation, with On/Off ratios larger than 106. The devices show asymmetric characteristics upon swapping the source and drain, a finding explained by the presence of Schottky barriers at the metal contact/MoSe2 interface. Using four-point, back-gated devices we measure the intrinsic conductivity and mobility of MoSe2 as a function of gate bias, and temperature. Samples with a room temperature mobility of ~50 cm2/V.s show a strong temperature dependence, suggesting phonons are a dominant scattering mechanism.

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S. Larentis, B. Fallahazad, E. Tutuc. 2012-11-13. Field-effect transistors and intrinsic mobility in ultra-thin MoSe2 layers. https://doi.org/10.1063/1.4768218

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