透明氧化物异质结的电阻开关效应研究

Based on the investigation of microstructure, optical and electrical properties of Ga2O3 films prepared by pulsed laser deposition method, the photoelectric performances of the p-n heterojunction combining with the intrinsic p- La0.67Ca0.33MnO3 films would be studied. Furthermore, the resistance switching effects of Ga2O3 film and its p-n heterojunction devices would be discussed, attempting to explore their potential application in future memory elements. The coupling relationship of heterojunction resistance memory characteristics and ferromagnetic properties will be studied. Resistance memory characteristics will be effectively regulated by the coupling relationship. In accordance with the changes of the microscopic information of the memory processes at the interface, the microscopic physical mechanism of the resistance memory characteristics will be revealed. The stability and fatigue of the Ga2O3 and its heterojunction thin film resistor memory device will be solved, and the relationship between the microstructure and performance and device functions and laws would be clarified.

本项目拟采用脉冲激光沉积法制备Ga2O3薄膜，研究薄膜的微观结构、光学性能和电学性能，开展n-Ga2O3/p- La0.67Ca0.33MnO3异质结的制备及其光电性能研究，探索Ga2O3薄膜的电阻开关性质，在此基础上，研究采用异质p-n结调整薄膜电阻开关性能，研究异质结的电阻记忆特性与铁磁特性的耦合关系，探索并利用其间的内在作用规律对电阻记忆特性进行有效调控。结合电阻记忆过程异质结界面处微观信息的变化，揭示电阻记忆特性的微观物理机制。解决Ga2O3及其异质结薄膜电阻存储器件的稳定性和耐疲劳性问题，阐明材料微观结构和性能与器件功能之间的关联和规律。

利用脉冲激光沉积方法在Al2O3衬底制备了氧化镓薄膜，研究了制备氧化镓薄膜时衬底温度对所得产物的影响，并对所制薄膜做了一定的表征。实验发现采用脉冲激光沉积技术所制得的薄膜在600℃以下以非晶态氧化镓为主，薄膜没有产生明显的结晶，而在 700℃以上时薄膜产生了的结晶。进一步研究发现，在 750℃制备的氧化镓薄膜致密均匀、质量较好。利用脉冲激光沉积技术在Al2O3衬底生长了厚度约为 150 nm Ga2O3薄膜，通过直流溅射工艺在 Al2O3衬底和Ga2O3薄膜上镀薄膜Au 电极，成功制备了 Au/Ga2O3/Al2O3/Au 结构，利用 Keithley4200 测试该器件的 I-V 曲线和阻变存储性能，在扫描过程中发现了双极型阻变行为, 发现该器件高低阻态窗口大，保持性能稳定。在Al2O3 衬底上制备了 Ga2O3/La0.67Ca0.33MnO3 异质结，测量该异质结的电学性能。