Top-gated multifunctional MoS2/silicon-on-insulator heterojunction

Van der Waals heterojunctions that combine materials with distinct properties enable the integration of multiple functionalities into a single device. Here, we demonstrate a top-gated n–n MoS2/silicon-on-insulator (SOI) heterojunction that can be configured into several operational modes: a thin-silicon channel transistor electrostatically modulated by a MoS2 secondary gate; a silicon channel phototransistor with a high responsivity of 64.1 A/W and a specific detectivity of 6.56 × 1012 Jones; an integrated diode-transistor showing a rectifying ratio approaching 104 and an on–off ratio up to 9600; and a self-powered photodiode featuring a fast response speed (rise/fall time of 3.2/3.6 μs). These results establish a pathway toward multifunctional electronic and optoelectronic integration using a simple commercial SOI platform.