Transferable Highly Crystalline Perovskite Ferroelectrics for Low-Power Memory

Data-centric applications demand low-power and compact memory solutions. Ferroelectric field-effect transistors (FeFETs) are promising candidates due to the high energy efficiency of ferroelectric switching and the elimination of selectors. However, ferroelectric materials that simultaneously demonstrate a low switching energy and compatibility with FeFET fabrication processes remain limited. In this work, we show that the transferable perovskite ferroelectric bismuth ferrite (BiFeO₃) with high crystal quality can be integrated with two-dimensional materials to realize low-power FeFETs. The transferred BiFeO₃ films exhibit a coercive field of 30 kV/cm and a leakage current of under 10^-5 A/cm² (at 1 MV/cm), resulting in a switching energy of 0.05 J/cm³. Leveraging the high-quality interface between transferred BiFeO₃ with molybdenum disulfide (MoS₂), we fabricate two types of FeFETs: a metal-ferroelectric-semiconductor (MFS) structure showing volatile memory and a metal-ferroelectric-metal-insulator-semiconductor (MFMIS) structure showing nonvolatile memory. Both device architectures exhibit low power consumption (1.5 fJ bit^-1 μm^-2 for MFS and 11.2 fJ bit^-1 μm^-2 for MFMIS). Utilizing these volatile and nonvolatile FeFETs, we constructed a low-power, compact, and all-FeFET computing system for pattern classification tasks, highlighting the potential of transferable BiFeO₃ for low-power memory and computing systems.