Two-Dimensional MOF-Based High-Performance Ferroelectric Field-Effect-Transistors with an Ultralow Off-State Current

Two-dimensional (2D) ferroelectrics open a new realm of nonvolatile memory and computing devices, while metal-organic framework (MOF) materials offer tremendous possibilities to design and optimize ferroelectric performance. Building a ferroelectric field effect transistor (FeFET) by integrating a 2D MOF ferroelectric gate with a 2D semiconducting channel provides new strategies towards ultralow power nonvolatile memory devices, yet no 2D MOF was found to be ferroelectric yet. Here we successfully develop 2D ferroelectric MOF nanosheets, {CuIIL2}n-MOF, and confirm its ferroelectricity down to 7 nm. A large polarization of ~14.2 μC/cm2, a small coercive field of ~33.3 V/um, and excellent endurability >10^6 cycles are found in 2D {CuIIL2}n-MOF nanosheets. This enables us to fabricate FeFETs using 2D {CuIIL2}n-MOF as the gate and MoS2 as the channel, achieving an on/off ratio of 10^7 with the ultralow low off-state current of 100 fA and tunable memory window, making it exceptional among known FeFETs and very promising for next-generation ultralow power memories and computing devices.