Quantifying Growth Mechanisms in Semiconductor Nanowires using Real Time Transmission Electron Microscopy

技术支持：本项目旨在通过IV族和III-V族材料的气-液-固和气-固-固生长过程对半导体纳米线生长进行基本了解。半导体纳米线是纳米科学领域研究的主要纳米结构材料之一。由于它们与现有器件加工方法的兼容性以及通过直径选择、掺杂和异质结构创建来控制它们的电子特性，它们有望成为未来电子和光电器件中的有源元件。该项目旨在获得新的见解和新的知识，以提供原子级的理解，从而开发纳米线集成方法。该方法是使用实时透射电子显微镜技术（TEM）来定量表征半导体纳米线生长的动力学。利用超真空和低压化学气相沉积方法的组合，IV族和III-V族纳米线将在TEM中原位生长，从而能够以真实的时间和高分辨率观察纳米线生长。研究领域包括晶体生长动力学，催化剂扩散的作用，异质结构形成过程中的相互扩散，缺陷形成机制和成核过程。非技术性：该项目涉及材料科学专题领域的基础研究问题，具有很高的潜在技术相关性。这项研究将有助于材料科学知识在基础层面上的新的理解和电子设备的能力。该计划的一个重要特点是通过在一个基本和技术上重要的领域对学生进行培训来整合研究和教育。纳米电子器件提供了超越传统光刻制造方法限制的希望。基于他们的研究成果，研究人员将与一家科学可视化公司（Seyet，LLC）合作，开发纳米线生长的逼真动画。这些动画将与更多的技术描述性信息和视频片段一起沿着，以创建独立的模块，通过普渡大学的新生工程课程和普渡大学的在线“NanoHub”资源进行传播。

Technical: This project seeks fundamental understanding of semiconductor nanowire growth by Vapor-Liquid-Solid and Vapor-Solid-Solid growth processes of Group IV and Group III-V materials. Semiconductor nanowires are one of the primary nanostructured materials under investigation in the field of nanoscience. Because of their compatibility with existing device processing methods and control over their electronic properties by way of diameter selection, doping and heterostructure creation, they hold promise as active elements in future electronic and optoelectronic devices. The project aims for new insights and new knowledge to provide an atomic level understanding leading to development of nanowire integration methodologies. The approach is to use real-time transmission electron microscopy techniques (TEM) to quantitatively characterize the dynamics of semiconductor nanowire growth. Utilizing a combination of ultrahigh vacuum and low-pressure chemical vapor deposition methods, group IV and group III-V nanowires will be grown in-situ in a TEM enabling observation of nanowire growth in real time and at high resolution. Areas of study include crystal growth kinetics, the role of catalyst diffusion, interdiffusion during heterostructure formation, defect formation mechanisms, and nucleation processes. Non-Technical: The project addresses basic research issues in a topical area of materials science having high potential technological relevance. The research will contribute materials science knowledge at a fundamental level to new understanding and capabilities in electronic devices. An important feature of the program is the integration of research and education through the training of students in a fundamentally and technologically significant area. Nanoelectronic devices offer the hope of allowing advances beyond the limits imposed by traditional lithographic fabrication methods. Based on their research outcomes, the investigators will work with a scientific visualization company (Seyet, LLC) to develop realistic animations of nanowire growth. These animations will be incorporated along with more technically descriptive information and video footage to create self-contained modules for dissemination through Purdue's Freshman Engineering curricula and the Purdue-based online "NanoHub" resource.