Nonvolatile logic inverters based on 2D CuInP₂S₆ ferroelectric field effect transistors

With the capability of in-memory computing, integrated nonvolatile logic devices can mitigate the back-and-forth movement of data between storage and logic units, thus effectively enhancing computational speed and reducing power consumption. In this work, two-dimensional (2D) CuInP₂S₆, which reveals robust polarization within a few nanometer thicknesses, was utilized as gate dielectric for ferroelectric field effect transistor (FeFET). Device with a ReS₂ channel demonstrated a high on/off ratio of current of 10⁵, accompanied by a substantial hysteresis window of 2.8 V. Additionally, ReS₂ FETs, gated with an h-BN layer, exhibited a switch ratio of 10⁸ and minimal hysteresis of 61.6 mV at room temperature, attributed to the atomically flat heterointerface with negligible traps. Leveraging the performance of these devices enabled the creation of a nonvolatile logic inverter, wherein the ReS₂/h-BN FET acts as the load transistor, and ReS₂/h-BN/CIPS FeFET serves as the driving unit. This configuration stably operates with low power consumption of 0.45 μW and outstanding retention exceeding 1000 s. This work presents a viable device architecture for designing nonvolatile logic circuits applicable in in-memory computing.