Flexible BaTiO ₃ Ferroelectric Nonvolatile Memory for Neuromorphic Computation

The use of BaTiO₃ (BTO) ferroelectric thin films in flexible ferroelectric memory offers a promising pathway for next-generation nonvolatile memory applications, given BTO's excellent ferroelectric properties, stability, high dielectric constant, and strong fatigue resistance. However, the fabrication of BTO on flexible substrates presents a significant technical challenge. In this study, we achieved high-quality, single-crystalline (111)-oriented BTO films on mica substrates through the design of buffer layers. The BTO films exhibit strong polarization properties (remnant polarization, 2<i>P</i>_r ∼15.63 μC/cm², and saturation polarization, 2<i>P</i>_s ∼36.61 μC/cm²), and the flexible BTO devices maintained exceptional stability under bending radii of 3.5 and 6 mm. After 10⁷ bipolar switching cycles, polarization showed only minor changes, with a retention time exceeding 10⁴ s. We further explored the application of flexible BTO ferroelectric memory in neuromorphic computing. The flexible BTO-based memory demonstrated adjustable synaptic behavior, effectively modulating EPSC (excitatory postsynaptic current) responses through pulse amplitude and width to simulate short-term memory. PPF (paired pulse facilitation) and LTP (long-term potentiation) behaviors verified its synaptic weight modulation capabilities, achieving 91.6% accuracy in neural network-based handwritten digit recognition after 10³ training cycles. These findings underscore the potential of flexible BTO ferroelectric memory for memory devices and neuromorphic computing, offering promising applications for wearable AI systems.