Relationship between resistive switching and Mott transition in atomic layer deposition prepared La2Ti2O7-x thin film. (1st January 2023)

• Record Type: Journal Article
• Authors: Wang, Yue; Kim, Minjae; Chabungbam, Akendra Singh; Kim, Dong-eun; Shao, Qingyi; Kymissis, Ioannis; Park, Hyung-Ho
• Is Part Of: Scripta materialia. Number 222(2023)
• Publication Date: 2023-01-01
• Subjects: Lanthanum titanium oxide -- Bipolar resistive switching -- Valence change memory -- Oxygen ion migration -- Mott transition; Materials -- Periodicals; Metallurgy -- Periodicals; Metalen; Legeringen; Materiaalkunde; Metals, metalworking and machinery industries; Metals; Electronic journals; 620.11
• DOI: 10.1016/j.scriptamat.2022.115050
• Languages: English
• ISSNs: 1359-6462

Abstract

Abstract: This study prepared Mott-metal state thin film La2 Ti2 O7-x on TiN substrate using atomic layer deposition, and confirmed W/La2 Ti2 O7-x /TiN clockwise forming-less resistive switching. The resistive switching mechanism was voltage-driven and oxygen vacancy doping-controlled Mott transition. Positive voltage induces the formation of oxygen vacancy in La2 Ti2 O7-x and change it from Mott-metal to Mott-insulator state, with the process reversible under negative voltage. We show that N doping can reduce the Ti 3+ ratio in La2 Ti2 O7-x film, producing a weakly correlated system compared with La2 Ti2 O7-x film without N-doping. Nitrogen doping also increased resistive switching operation voltage and reduced La2 Ti2 O7-x film on/off ratio. Thus, La2 Ti2 O7-x, was a promising candidate for the fabrication of resistive switching device based on Mott transition. Graphical abstract: Image, graphical abstract