Stresses, Deformation, and Dislocations in Thin Films: Combining Modeling and Simulations with Experiments

薄膜中的应力、变形和位错：将建模、仿真与实验相结合

• 批准号: 0311848
• 负责人: Shefford Baker
• 金额: --
• 依托单位: Cornell University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-07-15 至 2008-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0311848&HistoricalAwards=false
• 关键词: Stresses; Deformation; Dislocations; Thin; Films

Under this grant, dislocation dynamics simulations and transmission electron microscopy will be used to study the behavior of dislocations in thin metal films on substrates. A major objective of the program is to simulate meso-scale behavior of ensembles of dislocation near boundaries and interfaces for comparison with the overall mechanical behavior measured using substrate curvature and x-ray methods. The program includes both a 'bottom-up' study in which the configurations adopted by interacting pairs of dislocations and the strength of those interactions are examined, and a 'top down' study in which the behavior of many dislocations is simulated to search for controlling mechanisms. This combination of experiments and modeling is expected to provide direct evidence of mechanisms that lead to non-bulk-like behavior in thin films. The goal of this work is to study the dislocation mechanisms that lead to high stresses and non-bulk-like behavior in thin metal films in detail. Such films are indispensable elements in a wide range of nanofabricated devices, but typically suffer from very high stresses, which may lead to failure by deformation, void formation, or fracture.The mechanical behavior of thin films is not like that of bulk materials and is not well understood. In this program, dislocation dynamics simulations will be conducted to study how the dimensional constraints of a thin film affect dislocation behavior and mechanical properties. Dislocation configurations seen in simulations will be compared with those observed experimentally using transmission electron microscopy. This unique combination of experiments and modeling will provide a better understanding of the mechanical behavior of thin film metallizations. The project will support outreach efforts focused on high school teachers and students, and will engage undergraduates in research.

在此赠款下，位错动力学模拟和透射电子显微镜将用于研究底物上薄金属膜中位错的行为。该程序的一个主要目的是模拟近边界和接口的脱位集合的中尺度行为，以与使用底物曲率和X射线方法测量的整体机械行为进行比较。该程序既包括一项“自下而上”的研究，其中通过相互作用对采用的配置以及这些相互作用的强度进行了检查，以及一项“自上而下”的研究，其中模拟了许多脱位的行为以搜索控制机制。实验和建模的这种组合有望提供直接证据，证明导致薄膜中非粉状行为的机制。这项工作的目的是研究详细薄膜中导致高应力和非蓬松行为的脱位机制。这些薄膜是在各种纳米构造设备中必不可少的元素，但通常会遭受很高的应力，这可能会导致变形，空隙形成或断裂。薄膜的机械行为不像散装材料的机械行为，并且不太了解。在该程序中，将进行错位动力学模拟，以研究薄膜的维数约束如何影响位错行为和机械性能。在模拟中看到的位错构型将与使用透射电子显微镜实验观察到的构型进行比较。实验和建模的独特组合将更好地了解薄膜金属化的机械行为。该项目将支持集中于高中教师和学生的外展工作，并将吸引本科生从事研究。