【Device Papers】Oxygen vacancy induced stability in Ga₂O₃-based resistive switching devices

      Researchers from the Jimei University have published a dissertation titled "Oxygen vacancy induced stability in Ga₂O₃-based resistive switching devices" in Materials Science in Semiconductor Processing.

Abstract

      Oxygen vacancies, as key components of conductive filaments (CFs) in metal-oxide memristors, play a critical role in their resistive switching (RS) behaviors. In this work, we investigate oxygen vacancy induced RS behaviors in four kinds of Ag/Ga₂O₃/p⁺-Si memristors. The oxygen vacancy concentration is systematically modulated through controlled oxygen flow during magnetron sputtering deposition, followed by extended low-temperature vacuum annealing. XPS analysis revealed a descending order of oxygen vacancy concentration: annealed >0 sccm > 4 sccm >8 sccm. Electrical characterizations reveal that the operational stability of Ga₂O₃-based memristors is highly dependent on oxygen vacancies. The annealed device exhibits optimal performance, including a high On/Off ratio (10⁴), excellent cycling endurance (>10³ cycles), low variability in operating voltages and resistance states, excellent retention (10⁴ s), and outstanding D2D and C2C uniformity. Increased oxygen vacancies enable the optimized device to demonstrate stable RS behavior over 1000 consecutive DC sweep cycles, further confirming its reliability. Due to the increased oxygen vacancies, the vacuum-annealed device effectively suppresses the formation of random conductive paths and promotes the development of robust and confined CFs, thereby contributing to highly stable RS. Therefore, this strategy provides an important reference for the fabrication of high-performance Ga₂O₃-based memristors.

DOI：

https://doi.org/10.1016/j.mssp.2025.110376