Dopant Distribution, Motion, and Electrochemical Transfer in Resistive Switching Heterostructures

电阻开关异质结构中的掺杂剂分布、运动和电化学转移

• 批准号: 1105291
• 负责人: Marek Skowronski
• 金额: $ 44.77万
• 依托单位: Carnegie-Mellon University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-06-01 至 2014-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1105291&HistoricalAwards=false
• 关键词: Dopant; Distribution; Motion; Electrochemical; Transfer

Technical: Resistive switching in oxide-based heterostructures (metal-oxide-metal) has been known since the 1960's and has experienced a recent (since 2000) explosion of commercial and scientific interest, particularly for nonvolatile resistance-change random access memories.Resistive switching can be defined as the process in which a material or heterostructure is able to reversibly change (under electrical stimulation) between at least two resistance values that are stable with time. Most of the competing mechanisms proposed to explain resistive switching are qualitative and have only indirect observational support. However, they nearly all involve the redistribution of dopants in the oxide layer through ion motion. The project will interrogate in a quantitative fashion the electrical potential and oxygen distribution in metal-oxide-metal heterostructures, to quantify the oxygen motion within the oxide and across the metal-oxide interface, and develop a predictive computational model that captures the kinetic aspects of the switching process in three dimensions. The integrated research and education program described aims to understand, design, and produce nanoscale resistive switches appropriate for data storage and logic devices. Testing of the hypotheses that uniform ion redistribution within a heterostructure can be quantitatively characterized and ultimately optimized for resistive switching will be studied. To do so the research will determine the distribution of oxygen near, measure the oxygen exchange rates across, and quantify the electrical potential near metal-oxide junctions and oxide heterojunctions, designed and fabricated at Carnegie Mellon. A variety of characterization methods, including secondary ion mass spectroscopy, electron holography, scanning Kelvin probe microscopy, scanning electrochemical microscopy, capacitance-based methods, and spatially resolved secondary ion mass spectroscopy to interrogate ion redistribution and transfer will be used. A multi-dimensional continuum level computational model will be developed that describes the electrochemical transfer and ion redistribution in the resistive switch, which will be verified by testing of nanoscale resistive switching metal-oxide-metal devices, appropriate for future applications.Non-Technical: This project will have a broad societal impact by providing the fundamental underpinnings to device design and performance in novel ultra-high density data storage devices and reconfigurable logic technologies. The research activities will impact the education of a diverse group of Ph.D. and Undergraduate students through: laboratory and computational research, an advanced elective course, and a sophomore-level laboratory module. The new elective course, entitled 'Defect Interactions: Enabling Advanced Functional Materials and Devices,' will provide concrete examples of how defect interactions (such point defect motion near / across interfaces in memristors) act as enablers in advanced devices, including resistive switches, batteries, fuel cells, and high power electronics. A laboratory module will be implemented in the sophomore level core materials science course 'Defects in Materials.' It will demonstrate to students how point defects behave in electrochemical materials. Finally, the PIs will organize a research symposium on resistive switching at an international research conference.

技术支持：氧化物基异质结构中的电阻开关（金属-氧化物-金属）自20世纪60年代以来就已为人所知，（自2000年以来）商业和科学兴趣的激增，电阻切换可以定义为材料或异质结构能够可逆地改变的过程，（在电刺激下）在随时间稳定的至少两个电阻值之间。 大多数提出的竞争机制来解释电阻开关是定性的，只有间接的观测支持。然而，它们几乎都涉及掺杂剂通过离子运动在氧化物层中的再分布。该项目将以定量的方式询问金属-氧化物-金属异质结构中的电势和氧分布，以量化氧化物内和金属-氧化物界面上的氧运动，并开发一种预测计算模型，以三维方式捕获开关过程的动力学方面。 所描述的综合研究和教育计划旨在理解，设计和生产适用于数据存储和逻辑器件的纳米级电阻开关。测试的假设，均匀的离子再分布内的异质结构可以定量表征，并最终优化电阻开关将进行研究。为了做到这一点，研究将确定附近的氧气分布，测量氧气交换率，并量化在卡内基梅隆大学设计和制造的金属氧化物结和氧化物异质结附近的电势。将使用各种表征方法，包括二次离子质谱、电子全息、扫描开尔文探针显微镜、扫描电化学显微镜、基于电容的方法和空间分辨二次离子质谱来询问离子再分布和转移。将开发一个多维连续水平计算模型，描述电阻开关中的电化学转移和离子再分布，这将通过测试纳米级电阻开关金属-氧化物-金属器件进行验证，适用于未来的应用。该项目将通过为新的超声波设备的设计和性能提供基础，产生广泛的社会影响。高密度数据存储设备和可重构逻辑技术。研究活动将影响不同群体的博士教育。和本科生通过：实验室和计算研究，一个先进的选修课程，和一个走廊级的实验室模块。新的选修课程，题为“缺陷相互作用：使先进的功能材料和设备，”将提供具体的例子，如何缺陷相互作用（如点缺陷运动附近/跨界面忆阻器）作为先进设备，包括电阻开关，电池，燃料电池，和高功率电子。一个实验室模块将在大二核心材料科学课程“材料缺陷”中实施。它将向学生展示点缺陷在电化学材料中的表现。最后，PI将在一个国际研究会议上组织一个电阻开关研究研讨会。