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

摘要

The layered semiconducting transition metal dichaloogenides(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(Vn)shit 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 t0 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 mutilayer MoSg exhibit nearly negligible VIn rlloff at large source drain bias,and the D-FBG mutilayer 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 Vn roll-off and ambipolar transport for high-performance and low-power logic applications.