【International Papers】Correlation between oxygen flow-controlled resistive switching and capacitance behavior in gallium oxide memristors grown via RF sputtering

      Researchers from the Tech University of Korea have published a dissertation titled " Correlation between oxygen flow-controlled resistive switching and capacitance behavior in gallium oxide memristors grown via RF sputtering " in Heliyon.

Abstract

      We studied on the bipolar resistive switching (RS)-dependent capacitance of Ga₂O₃ memristors, grown using controlled oxygen flow via a radio frequency sputtering process. The Ag/Ga₂O₃/Pt memristor structure was employed to investigate the capacitance changes associated with RS behavior and oxygen concentration. In the low-resistance state (LRS), capacitance increased by over 60 times compared to the high-resistance state (HRS). Furthermore, in the HRS state, increasing the oxygen flow from 0 to 0.3 sccm resulted in an 80 % decrease in capacitance, while in the LRS state, capacitance increased by 128 %. These results indicate that RS-dependent capacitance in Ga₂O₃ memristors is influenced by the density of oxygen vacancies. The presence of oxygen vacancies affects charge storage capacity and capacitance, with higher oxygen concentrations leading to reduced capacitance in HRS and increased capacitance in LRS. The results contribute to the understanding of the capacitance behavior in Ga₂O₃ memristors and highlight the significance of oxygen vacancies in their operation.

Fig. 1XPS (a) O 1s and (b) Ga 3d peaks of Ga₂O₃ film grown with different oxygen flow rates. (c) O_II, Ga³⁺ and Ga¹⁺-related peak intensity of Ga₂O₃ film as a function of oxygen flow rate.

Fig. 2(a) Plot of (αhν)² against E for the Ga₂O₃ films with different oxygen flow. Inset is the absorbance spectra of the same films. (b) Energy bandgap of Ga₂O₃ films grown by different oxygen flow rates ranging from 0 sccm to 0.3 sccm in RF sputter.

Paper Link：https://doi.org/10.1016/j.heliyon.2023.e23157