Dual-Channel WS2/WSe2 Heterostructure with Tunable Graphene Electrodes

Two-dimensional semiconductor heterostructures provide significant research potential for electronic and optoelectronic applications because of their scaled thickness, pristine heterostructure interface, and ultrafast carrier transport. Herein, we report a dual-channel field-effect transistor based on ntype WS2 and p-type WSe2 layered heterostructure using multilayered graphene as electrodes to enable electron-dominated ambipolar electrical transport. WS2 exhibits mobility of 20 cm2 V-1 s(-1) and an on/off ratio of 105, whereas WSe2 exhibits mobility of 5 cm2 V-1 s(-1) and an on/off ratio of 104. Furthermore, our results show negative Schottky barrier heights between dual-channel heterostructure and multilayered graphene. The proposed design reduces complications in the fabrication of devices with integrated heterostructures, particularly for complementary metal-oxide semiconductor inverter applications.