电场调控尖晶石型铁氧体薄膜阻变与磁性及其关联特性研究

The resistive switching effect and correlated magnetic modulation in spinel ferrite thin films have expanded its physical connotation and potential application. It shows scientific importance and application potential to study the electric modulated resistive switching and magnetic and their correlation which integrate the two attributes of charge and spin in spinel ferrite thin films. In this project, we intend to fabricate spinel ferrite thin films and electrode materials to construct electrode/spinel ferrite thin film/electrode prototype devices by magnetron sputtering. The effects of preparation parameters, annealing methods, film types, device structures and electrode materials on the resistive switching and magnetic of films will be extensively explored. The magnetic corresponding to the different resistance states and the microcosmic law of resistive switching and magnetic domain reversal in films will be investigated to obtain the law of electric modulated resistive switching and magnetic in films. The magnetoresistance corresponding to the different resistance states and the effects of magnetic to resistive switching in films will be researched to figure out the law of magnetic modulated resistive switching. Moreover, studies will also be conducted on the correlation of electric modulated resistive switching and magnetic in spinel ferrite thin films in combination with electric and magnetic field to make deep understanding of the electric modulated mechanism of resistance/magnetism and provide basis of early research for new-type resistive switching/magnetic coupling devices.

尖晶石型铁氧体薄膜电致阻变效应及其与阻变相关联的磁调制，拓展了该类材料的物理内涵与应用领域，研究电场调控尖晶石型铁氧体薄膜阻变与磁性及其关联特性，融合电荷与自旋两大属性，具有重要的物理意义与应用前景。本项目拟采用磁控溅射法制备尖晶石型铁氧体薄膜与电极材料，构筑电极/尖晶石型铁氧体薄膜/电极结构原型器件。研究制备条件、退火方式、薄膜类型、器件结构、电极材料等对薄膜电致阻变与薄膜磁性的影响规律；研究薄膜不同阻态的磁性，观测电阻转变与磁畴翻转的微观规律，获得电场调控薄膜阻变与磁性的规律；研究薄膜不同阻态的磁电阻以及磁场对阻变效应的影响，获得磁场调控阻变的规律；结合电场、磁场的协同作用，获得电场调控尖晶石型铁氧体薄膜阻变与磁性的关联特性，深入理解电阻/磁性的电场调控机制，为有可能的新型阻变/磁性耦合与调制器件提供前期的研究基础。

电阻变换效应及其阻变随机存储器的研究具有重要的科学意义和应用前景，是功能材料领域研究的前沿热点，其多种潜在特性及其相关物理机制亟待深入探索。本项目制备了多种氧化物薄膜及其异质结，研究了这些薄膜异质结的电阻变换效应及其关联的磁性性质，获得电场调控薄膜电阻与磁性的规律；研究探索了电阻/磁性的电场调控机制，建立新型阻变/磁性耦合与调控器件的原始模型。本项目主要完成了以下工作内容：以反铁磁性氧化物薄膜NiO、室温顺磁性氧化物薄膜Mn3O4、Pt/Co3O4、铁磁性氧化物薄膜CuFe2O4、Fe2O3为代表性研究对象，优化了上述薄膜的制备条件，探索制备条件对薄膜性能的影响规律，所构筑的氧化物异质结器件中观察到典型的双极性电阻变换效应，阻变倍率达到104以上，具有良好的保持性与可重复性，随着施加不同极性与大小的电压脉冲，器件表现出多级阻变效应，同时不同阻态下的薄膜磁性呈现出与电阻相关联的变化，主要利用载流子注入束缚/解束缚与氧空位迁移模型来解释阻变和磁性的变化。本项目所取得的相关成果在下一代不挥发性阻变存储器及其相关磁性器件的应用等方面提供前期的研究基础。. 在本项目的资助下，在国内外重要期刊上发表了学术论文12篇。