阻变效应的光场调控规律及机理研究

阻变存储器是一种有前途的高速、高密度和低功耗的新型非易失性存储技术。通常，阻变存储器基于存储介质中纳米导电细丝的可逆通断实现数据存储，但纳米导电细丝为本征的室温亚稳态相，使得阻变存储器难以兼具低擦写功耗和高稳定数据保持特性，严重制约了其综合性能。针对这一问题，本项目提出“利用光场来调控阻变效应”，拟选用兼具优异阻变与光电特性的铁酸铋薄膜作为存储介质构建阻变器件，通过系统表征不同电场、光场加载方式下各种构型、尺寸以及微结构器件的电阻状态演化过程，澄清电场、光场协同作用下固体介质中的离子输运与氧化还原反应过程，阐明光场对器件阻变过程与数据保持特性的调控规律和机理，进而发展出使得器件兼具低擦写功耗和高稳定数据保持特性的光场加载方式，为阻变存储器的综合性能优化提供理论依据和指导。

Resistive random access memory (RRAM) is a very promising high-speed, high-density and low-power nonvolatile memory candidate. The data are usually recorded via reversible formation and rupture of nano conducting filaments in storage media. However, nano conducting filaments are intrinsically metastable at room temperature, making RRAM almost impossible to own low-power operation and long-time data retention simultaneously. To solve this issue, we propose the modulation of resistive switching effect by light and plan to research it based on RRAM devices using BiFeO3 films with good resistive switching and photoelectric characteristics as storage media. The research will start with the fabrication of BiFeO3-based RRAM devices with various configurations, sizes and microstructures. Then, by systematically characterizing their resistance evolutions under different electric field and light loading methods, ion transport processes and redox reactions in these devices will be revealed, and the effects of light on resistive switching as well as data retention characteristics of these devices and related mechanisms will be clarified. Finally, a light loading method that enables RRAM to own low-power operation and long-time data retention simultaneously is expected to be developed. These results would provide a theoretical basis and guide for performance enhancement of RRAM.