Thickness-dependent carrier mobility of ambipolar MoTe_2： Interplay between interface trap and Coulomb scattering

摘要

The correlation between the channel thickness and the carrier mobility is investigated by conducting static and low frequency (LF) noise characterization for ambipolar carriers in multilayer MoTe_2 transistors. For channel thicknesses in the range of 5-15 nm, both the low-field carrier mobility and the Coulomb-scattering-limited carrier mobility (µ_c) are maximal at a thickness of ~10nm. For LF noise, the inteplay of interface trap density (N_(sT)), which was minimal at ~10nm, and the interracial Coulomb scattering parameter (x_(5c))» which decreased up to 10nm and saturated above 10nm, explained the mobility (µ_c) peaked near 10nm by the carrier fluctuation and charge distribution.