Creation of ferroelectric flux-closure transistor array for non-volatile field-effect memory

Ferroelectric flux-closures are promising candidates for high-performance memories, offering reversible switching and low power consumption. However, integration of ferroelectric flux-closures into memory devices is elusive, mostly due to the constraint from the substrate on which polar film is grown. Here, we demonstrate ferroelectric field-effect transistors (Fe-FETs) based on freestanding films with identical polar flux-closures. The retention of flux-closure in the freestanding film is driven by the intrinsic self-organization of polarization to minimize the combined elastic and electrostatic energies. The flux-closure structures exhibit low coercive electric field (Ec), negligible leakage currents, and endurance up to 1010 cycles. Furthermore, the as-fabricated complementary metal-oxide-semiconductor (CMOS)-compatible Fe-FET arrays achieve reversible information writing and erasure. They set a benchmark for perovskite-structured devices by simultaneously achieving a large memory window of 0.43 V/nm and a high on/off ratio of 108, while maintaining endurance and stability. Our work paves the way for ferroelectric devices in future semiconductor industries. Ferroelectric flux-closures are promising for high-performance memory but are constrained by the substrate. Gong et al. integrate freestanding ferroelectric flux-closure arrays into field-effect transistors to demonstrate information writing and erasing, addressing whether topology-based devices can serve as functional memory.