Type-Switchable Inverter and Amplifier Based on High-Performance Ambipolar Black-Phosphorus Transistors

Black phosphorus (BP), an emerging 2D layered material, is promising for nanoelectronic applications due to its high carrier mobility and saturation velocity. A high performance ambipolar BP field-effect transistor (FET), fully assembled from 2D materials, is demonstrated. It exhibits two-terminal mobility of 540 cm(2) V-1 s(-1) for holes and 250 cm(2) V-1 s(-1) for electrons at room temperature. The ambipolar charge transport of the BP FET allows it to operate as a p- and n-type switchable inverter with operating frequency up to 160 kHz through simply changing the polarity of the supply voltage. At the same time, the voltage gain of the inverter is higher than 1, suggesting that it is suitable for logic-circuit applications. Moreover, it is shown that the ambipolar BP FET can function as an output-polarity controllable amplifier through tuning of the input and supply voltages. This demonstration paves the way for future BP applications in logic circuits.