2D Ferroelectric Metal–Organic Frameworks for Ultralow Power Field Effect Transistors

Abstract 2D ferroelectrics open a new realm of nonvolatile memory and computing devices, while metal–organic frameworks (MOF) offer tremendous possibilities to design and optimize ferroelectric performance. Integrating a MOF ferroelectric gate with a semiconducting channel provides new strategy toward ultralow power ferroelectric field effect transistors (FeFETs), yet no 2D MOF is experimentally demonstrated to be ferroelectric yet. Here, the study successfully develops 2D ferroelectric MOF nanosheets, {CuL 2 (H 2 O) 2 (NO 3 ) 2 (H 2 O) 1.5 ·(CH 3 OH)} ∞ wherein L denotes PhPO(NH 4 Py) 2 , abbreviated as {Cu II L 2 } n ‐MOF, and confirm its ferroelectricity down to 7 nm thickness. A large polarization of ≈14.2 µC cm −2 , small coercive field of ≈33.3 V µm −1 , and excellent endurability >10 6 cycles are found in 2D {Cu II L 2 } n ‐MOF nanosheets. This enables to fabricate FeFETs using 2D {Cu II L 2 } n ‐MOF as the gate and MoS 2 as the channel, achieving an on/off ratio of 10 7 with ultralow 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