Structural Transitions during Catalyzed Growth of Semiconductor Nanowires

半导体纳米线催化生长过程中的结构转变

• 批准号: 1206511
• 负责人: Wei Cai
• 金额: $ 55.5万
• 依托单位: Stanford University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-07-01 至 2016-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1206511&HistoricalAwards=false
• 关键词: Structural; Transitions; during; Catalyzed; Growth

Technical Description: This computational and experimental research project aims to answer several fundamental questions in the Au-catalyzed vapor-liquid-solid growth of Ge and Si nanowires. In particular, what mechanisms control kinking of nanowires and how does metastable hexagonal-close packed Au form when growth terminates? A three-dimensional continuum phase field model connects atomistic simulations and experimental observations, which use both ex-situ and in-situ characterization methods, and a rapid thermal chemical vapor deposition system. The project also investigates methods of controlling growth to avoid defects and to facilitate synthesis of abrupt doped junctions and axial Si-Ge heterostructures.Non-technical Description: This project has a broader impact on a wide range of materials research problems in which a close connection between atomistic modeling and experiments is desirable. Results of this project provide lecture materials on atomistic simulations, thermodynamics and kinetic processes in materials synthesis. The project engages undergraduates through summer research. The science education outreach activity introduces San Jose-area high-school students to crystal growth concepts through interactive Android Apps based on a two-dimensional phase field model.

技术描述：这项计算和实验研究项目旨在回答金催化的Ge和Si纳米线的气-液-固生长中的几个基本问题。特别是，是什么机制控制着纳米线的扭结，以及当生长终止时亚稳的六角密排Au是如何形成的？三维连续相场模型连接了原子模拟和实验观察，使用了非原位和原位表征方法，以及快速热化学气相沉积系统。该项目还研究了控制生长以避免缺陷的方法，并促进了突然掺杂结和轴向Si-Ge异质结的合成。非技术描述：该项目对广泛的材料研究问题有更广泛的影响，其中原子模拟和实验之间的密切联系是可取的。该项目的成果提供了关于材料合成中的原子模拟、热力学和动力学过程的讲座材料。该项目通过暑期研究吸引了本科生。科学教育推广活动通过基于二维相场模型的互动Android应用程序，向圣何塞地区的高中生介绍晶体生长的概念。