Structural Transitions during Catalyzed Growth of Semiconductor Nanowires

技术说明：这个计算和实验研究项目的目的是回答几个基本问题，在金催化气-液-固生长的锗和硅纳米线。特别是，什么机制控制扭结的纳米线，以及如何亚稳六方密堆积Au的形式时，生长终止？一个三维连续相场模型连接原子模拟和实验观察，使用非原位和原位表征方法，和一个快速的热化学气相沉积系统。该项目还研究了控制生长的方法，以避免缺陷，并促进突然掺杂结和轴向硅锗heterostructures.Non-technical Description的合成：该项目具有广泛的影响广泛的材料研究问题，其中原子建模和实验之间的密切联系是可取的。本计画之成果提供材料合成中原子模拟、热力学与动力学过程之演讲材料。该项目通过暑期研究吸引本科生。科学教育推广活动通过基于二维相场模型的交互式Android应用程序向圣何塞地区的高中学生介绍晶体生长概念。

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.