Role of Oxygen Vacancies at the TiO2/HfO2 Interface in Flexible Oxide‐Based Resistive Switching Memory

Abstract Flexible memory is highly desirable for data storage in portable wearable electronics. Here, a flexible bilayer TiO 2 /HfO 2 ‐architecture‐based resistive random access memory (RRAM) is fabricated a on polyethylene naphthalate (PEN) substrate, and exhibits outstanding uniformity, high durability, and excellent mechanical flexibility. The coefficients of variations for high and low resistance state are ≈3.2% and ≈3%, respectively. No performance degradation is observed under mechanical stress with bending radius ranging from 70 to 10 mm. Interestingly, the performance degradation after long‐term stability tests can be recovered. An asymmetric hourglass‐shaped oxygen vacancy (Vo) distribution at the HfO 2 /TiO 2 interface plays a key role in high performance of this flexible RRAM device. The proposed flexible RRAM devices have potential applications in wearable electronics.