Ultralow power switching of Ta₂O₅/AlO_X bilayer synergistic resistive random access memory

In this work, an ultra low power switching is achieved in Ta₂O₅-based resistive random access memory (RRAM) device through inserting AlOx film as tunneling layer. After optimizing the thickness of the AlO_X layer, the operating current of the device with 15 nm AlO_X is reduced to lower than 100 nA with a switching window about 151, and the ultra-low power consumptions of 586 pW and 40.2 nW are achieved for set and reset process, respectively. According to the local conductive filament formation characterization from high-resolution transmission electron microscope and the calculation from Schottky emission formula, a switching mechanism based on the formation of local oxygen vacancies conductive filament in AlO_X layer is proposed to explain the ultralow power switching of the Ta₂O₅/AlO_X bilayer synergistic RRAM device. (paper)