Duan Research Group

Hetero-integrated Nanostructures and Nanodevices


Suppressed threshold voltage roll-off and ambipolar transport in multilayer transition metal dichalcogenide feed-back gate transistors

Yang Liu, Peiqi Wang, Yiliu Wang, Yu Huang, Xiangfeng Duan

Nano Res. 13, 1943-1947 (2020)

The layered semiconducting transition metal dichalcogenides (s-TMDs) have attracted considerable interest as the channel material for field-effect transistors (FETs). However, the multilayer s-TMD transistors usually exhibit considerable threshold voltage (Vth) shift and ambipolar behavior at high source-drain bias, which is undesirable for modern digital electronics. Here we report the design and fabrication of double feedback gate (FBG) transistors, i.e., source FBG (S-FBG) and drain FBG (D-FBG), to combat these challenges. The FBG transistors differ from normal transistors by including an extra feedback gate, which is directly connected to the source/drain electrodes by extending and overlapping the source/drain electrodes over the yttrium oxide dielectrics on s-TMDs. We show that the S-FBG transistors based on multilayer MoS2 exhibit nearly negligible Vth roll-off at large source-drain bias, and the D-FBG multilayer WSe2 transistors could be tailored into either n-type or p-type transport, depending on the polarity of the drain bias. The double FBG structure offers an effective strategy to tailor multilayer s-TMD transistors with suppressed Vth roll-off and ambipolar transport for high-performance and low-power logic applications.
UCLA, Department of Chemistry and Biochemistry
607 Charles E. Young Drive East, Box 951569
Los Angeles, CA 90095-1569
E-mail: xduan@chem.ucla.edu