Effect of oxygen vacancies injection on the resistance switching properties of Hf0.5Zr0.5O2

The regulation of oxygen vacancies (Vo) concentration has become an important research direction for further improving the resistance switching (RS) performance of materials and developing RS memory devices. In this study, the Pt/ Hf0.5Zr0.5O2/LaNiO3 (Pt/HZO/LNO) structure is prepared via a sol-gel method using LNO as the oxide electrode and Vo reservoir layer. Pt/HZO/Pt and Pt/HZO/LiNbO3(LN)/LNO structures are also prepared as a comparison. The current density-voltage (J-V) characteristics and RS effects of these materials are presented in detail. Both the Pt/HZO/Pt and Pt/HZO/LNO structures demonstrate obvious RS effect, and their RS mechanisms can be attributed to the formation of a Vo conductive-filament (CF) channel. However, in the Pt/HZO/LNO structure, Vo originate from two mechanisms under different negative voltages, i.e., from the HZO itself and through injection into HZO from LNO, resulting in its RS characteristics being different from the Pt/HZO/Pt structure. Excessive Vo injected into HZO from the LNO layer leads to a further decrease in the resistance of the Pt/HZO/LNO structure under a negative electric field. Moreover, there is no significant RS effect in the Pt/HZO/LN/LNO structure because it is difficult to form CF channel in the LN film.