Observed Hafnium Nanocrystals in HfTiO Compound Film Bring Excellent Performance for Flexible Selector in Memory Integration
In this study, HfTiO compound film on polyethylene naphthalate (PEN) has been investigated and designed as the selective layer material to fabricate flexible selector device since selector is considered as a promising candidate for solving the sneak current issue in high-density memory integration. According to material analysis, hafnium nanocrystals have been observed in the HfTiO film to play a key role in performance improvement of the selector. The correlation between the HfTiO material and the corresponding current conduction mechanisms and the proposed physical mechanism model with hafnium nanocrystals have been thoroughly investigated to clarify and explain the enhanced selective behavior including high uniformity, excellent endurance and fast operation speed. Moreover, the selector with HfTiO film exhibits superior bending reliability with no working performance degradation under a bending radius ranging from 50 mm to 30 mm, indicating this selector’s excellent flexibility and its applicability in flexible application scenarios. These achievements for Pt/HfTiO/ITO selector induced by HfTiO film with hafnium crystals offer great potential for material and interfaces design in future memory integrations and flexible applications.