Channel Thickness-Dependent Degradation of Field-Effect Mobility in Multilayer MoS2 Transistors

Abstract

Two-dimensional(2D) semiconductorssuch as molybdenumdisulfide(MoS2) may serve as state-of-the-artlogicdevicesas we progresstowardthe 2 nm technologynode. Here, we show that mobilitydegradationis influencedby the channelthicknessof multilayerMoS2transistors.ThickerMoS2channelsexhibitedless degradationof field-effectmobilitycaused by thetransverseelectricfield (E-field),given the considerablebulk conductioncurrent.Kelvin probe force microscopy(KPFM)was usedto measurethe channelthickness-dependentcontactpotentialdifferencegradient.Numericalsimulationconfirmedthat the verticalE-field was well screenedby the bulk conductionchannel.The results enhanceour understandingof multilayerMoS2transistoroperationand will enable performanceoptimization.