Highly reliable bipolar resistive switching of tantalum oxide-based memory using Al2O3 diffusion barrier layers

We present a novel bipolar resistive switching memory based on TaOx, featuring a Ru/Al2O3/Ta2O5/TaOx/Al2O3/W structure. Thin Al2O3 layers play a crucial role as diffusion barriers, preventing undesirable interfacial reactions at the top and bottom interfaces. They support the stable formation of the Schottky barrier near the Ru top electrode through redox reactions during operation, resulting in highly reliable bipolar resistive switching. The device exhibits excellent memory performance, including a fast operation speed (∼10 ns), good switching endurance (∼106 cycles), and robust data retention (>104 s at 200 °C).