CAREER: Microstructure Evolution and Interfacial Reaction Paths in Cu Alloy Thin Films

99844778 ramanath这项资助旨在从原子水平上理解溶质诱导的金属合金薄膜的晶粒尺寸和织构演变。目的是将微观结构和界面化学对薄膜性能的影响联系起来。根据Cu-Mg和Cu-Al的低固溶度和高固溶度选择两种模型体系进行系统研究，揭示了溶解度和过饱和度对微观结构和界面化学演变的影响。具体的相关目标是：1)揭示薄膜生长和沉积后退火过程中溶质偏析、晶粒生长和界面反应的顺序和动力学；2)揭示溶质偏析路径（例如，颗粒间和颗粒内）和表面/界面形态、结构和化学；3)了解析出相形态、析出相-基体晶体学（如相干性）和界面化学对晶粒尺寸和织构演化的影响；4)了解织构和溶质添加对电迁移的影响，以及界面化学对氧化和扩散势垒性能的影响。CAREER教育计划的总体主旨是开发创新的教学工具和方法，使学生获得高质量的技术知识，吸收独立学习的艺术，为成功的职业生涯做好准备。将“材料表征”远程学习课程转变为互动形式，并开设研究生研讨课程、薄膜材料及其加工本科选修课，以及与薄膜材料相关的计算机/视频模块，整合到上述课程的互动课堂和外展活动中。由此产生的知识将能够通过微观结构的原子水平控制和界面化学通过战略性的溶质添加和退火来定制薄膜的性能。重点是铜合金，因为铜在微电子互连应用中的重要性。向Cu中添加溶质可以防止Cu扩散到二氧化硅中，从而改善附着力和电迁移阻力。揭示溶质诱导Cu薄膜性能增强的机制对于通过合金化可重复地创建更小（更快）和更可靠的互连结构是至关重要的

9984478RamanathThis grant seeks an atomic-level understanding of solute-induced grain size and texture evolution in metal alloy films. A goal is to correlate the effects of microstructure and interface chemistry on film properties. Systematic studies are carried out on two model systems, Cu-Mg and Cu-Al, chosen based on their low and high solid-solubilities, respectively, to reveal the effects of solubility and supersaturation on microstructure and interface chemistry evolution. The specific interrelated goals are: 1) reveal the sequence and kinetics of solute segregation, grain growth, and interfacial reactions during film growth and post-deposition annealing; 2) reveal solute segregation paths (e.g., inter- vs. intra-granular) and surface/interface morphology, structure, and chemistry; 3) understand the influence of precipitate morphology, precipitate-matrix crystallography (e.g. coherency), and interface chemistry on grain size and texture evolution; and 4) understand the effects of texture and solute additions on electromigration, and interface chemistry on oxidation and diffusion barrier properties. The overall thrust of the CAREER educational plan is to develop innovative teaching tools and methods to enable students to acquire top-quality technical knowledge, assimilate the art of learning independently, and prepare them for successful professional careers. The distance-learning Materials Characterization course will be converted into an interactive format and a graduate seminar course and an undergraduate elective on thin film materials and processing will be created as well as computer/video modules related to thin film materials for integration in interactive class sessions of the above courses and outreach activities.%%%The resulting knowledge will enable the tailoring of film properties by atomic-level control of microstructure and interface chemistry through strategic solute additions and annealing. The focus is on copper alloys because of the importance of Cu for interconnect applications in microelectronics. Solute additions to Cu have shown promise for preventing Cu diffusion into silica thereby improving adhesion and electromigration resistance. It is essential to reveal the mechanisms of solute-induced film-property enhancements in Cu films to reproducibly create smaller (faster) and more reliable interconnect structures through alloying.***