Emergence of ferroelectricity in P‐Type 2D In1.75Sb0.25Se3

P‐type Two‐dimensional ferroelectric semiconductors (2D FeSs) play an increasingly essential role in the advanced nonvolatile and morphotropic beyond‐Moore electronic devices with high performance and low power consumption. But reliable p‐type 2D FeS with holes as majority carriers are still scarce. Here, we report the first experimental realization of room‐temperature ferroelectricity in van der Waals layered β‐In1.75Sb0.25Se3 down to fewlayer. The origin of ferroelectricity in β‐In1.75Sb0.25Se3 comes from aliovalent elemental substitution –antimony substituting to the indium sites (SbIn)– changing the local environment of the central‐layer Se atoms. Thanks to the intrinsic ferroelectric and semiconducting natures, ferroelectric semiconductor field‐effect transistor (FeSFET) devices based on β‐In1.75Sb0.25Se3 exhibits reconfigurable, multilevel nonvolatile memory (NVM) states, which can be successively modulated by gate voltage stimuli. Furthermore, the inherent operation mechanism, owing to the switchable polarization, indicates that a neuromorphic memory is also possible with our 2D FeSFETs. These presented results facilitate the technological implementation of versatile 2D FeS devices for next‐generation logic‐in‐memory approach for Internet‐of‐Things (IoT) entities.This article is protected by copyright. All rights reserved.