Dependent of switching polarity for HfOx-based memory on doping content and current

• Published in: Solid-state electronics Vol. 178; p. 107979
• Main Authors: Guo, Tingting, Tan, Tingting, Duan, Li, Wang, Yuxuan, Wang, Zizhe
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.04.2021
• Subjects: Doping concentration; Forming process; HfOx film; Switching polarity; Forming process; Doping concentration; HfOx film; Switching polarity
• ISSN: 0038-1101; 1879-2405
• DOI: 10.1016/j.sse.2021.107979

[Display omitted] •BRS and URS behaviors of HfOx:Cu samples under different conditions were studied.•Better control of filaments led to the uniform switching performance of BRS sample.•Forming processes under different voltage polarities were investigated.•The type and number of defects showed a crucial role on switching behaviors. Dopants-dependent polarity transition of switching behaviors for HfOx:Cu-based RRAM were investigated. By inducing different concentrations of Cu dopants and setting compliance current, the BRS and URS behaviors of HfOx:Cu films were demonstrated. The chemical bonding states and the doping concentrations of HfOx:Cu films were analyzed by XPS technology. The electroforming processes of BRS and URS behaviors under different polarity of applied voltage were explored to understand the different behaviors of HfOx:Cu films. The uniform distribution of resistances and switching voltages, large memory window and good reliability can be observed for BRS sample. While the excess dopants in the film resulted in the poor reliability of URS sample. The different switching behaviors was closely related to the type and number of defects in the film and their migration may show some effect on multi-level behavior. The switching mechanisms of BRS and URS behaviors of HfOx:Cu films were clarified in the view of oxygen vacancies and Cu ions, and the physical models were proposed.