Resistive Switching Behavior in Ferroelectric Heterostructures.

Resistive random-access memory (RRAM) is a promising candidate for next-generation nonvolatile random-access memory protocols. The information storage in RRAM is realized by the resistive switching (RS) effect. The RS behavior of ferroelectric heterostructures is mainly controlled by polarization-dominated and defect-dominated mechanisms. Under certain conditions, these two mechanisms can have synergistic effects on RS behavior. Therefore, RS performance can be effectively improved by optimizing ferroelectricity, conductivity, and interfacial structures. Many methods have been studied to improve the RS performance of ferroelectric heterostructures. Typical approaches include doping elements into the ferroelectric layer, controlling the oxygen vacancy concentration and optimizing the thickness of the ferroelectric layer, and constructing an insertion layer at the interface. Here, the mechanism of RS behavior in ferroelectric heterostructures is briefly introduced, and the methods used to improve RS performance in recent years are summarized. Finally, existing problems in this field are identified, and future development trends are highlighted.