NER: Focused Ion Beam (FIB) Micromachining and Advanced Characterization of Carbon Nanotube-Metal Junctions

该项目是响应纳米尺度科学与工程计划，NSF 01-157， NER类。本研究的目的是利用高分辨率透射电子显微镜（TEM）、电子能量损失光谱和能量过滤透射电子显微镜，发展碳纳米管-金属结的局域原子级结构和化学界面表征方法。聚焦离子束微加工将用于制造碳纳米管（CNTs）上的铂金属触点，以及用于进一步的TEM分析的局部试样横截面。本研究的目标有三个：(1)推进纳米级表征技术，以在原子水平上理解fib辅助金属沉积对CNT/Pt界面结构和化学的影响；(2)开发了碳纳米管-金属结的选择性（局部）高分辨率TEM和电子能量损失谱的样品制备技术；(3)具有原子级扩散和形貌控制的可重复金属接触制造技术的发展。该研究将把纳米物体/金属结的研究推进到对界面结构和化学的原子水平的理解。开发碳纳米管/金属局部截面技术的优化方法，对结的高分辨率化学和结构分析将有助于大多数纳米尺度物体和未来纳米器件的研究。具有已知性质的碳纳米管/金属结的可控纳米制造将有助于对纳米材料和结构进行可靠的电气测试，用于从化学传感器到场效应晶体管的各种应用，从而使新设备的制造能够服务于人们的日常生活。两名研究生将直接参与该项目，学习先进的表征技术，如透射电子显微镜、电子能量损失光谱和FIB微mashining。该计划产生的专业知识将直接用于教育过程中，以教授当前和未来的科学家/技术人员。PI将组织和举办科学研讨会，将把新的数据纳入研究生课程，以促进知识和发展的方法的传播。

This project was received in response to Nanoscale Science and Engineering initiative, NSF 01-157, category NER. The goal of the research is to develop the methodology of localized atomic-level structural and chemical interfacial characterization of carbon nanotube-metal junctions using high resolution transmission electron microscopy (TEM), electron energy loss spectroscopy and energy filtered TEM. The Focused Ion Beam micromachining will be used to fabricate platinum metal contacts onto carbon nanotubes (CNTs), and also for localized specimen cross-sectioning for further TEM analysis. The objectives of the study are threefold: (1) advancement of nanoscale characterization techniques to achieve an understanding of the effects of FIB-assisted metal deposition on the CNT/Pt interfacial structure and chemistry at atomic level; (2) development of a specimen preparation technique for selective (localized) high-resolution TEM and electron energy loss spectroscopy of CNT-metal junctions; (3) development of reproducible metal contact fabrication technique with atomic-level control of inter-diffusion and morphology. The research will advance the nanoobject/metal junction studies to the atomic-level of understanding of the interfacial structure and chemistry. Development of optimized methodology of CNT/metal localized cross-sectioning technique for high-resolution chemical and structural analysis of the junction will be useful for studies of the majority of nanoscale objects and future nano-devices. Controlled nano-fabrication of CNT/metal junctions with known properties will facilitate the reliable electrical testing of the nanosized materials and structures for variety of applications ranging from chemical sensors to field effect transistors, thus enabling fabrication of new devices to serve people in their everyday life. Two graduate student will be directly involved in the program gaining knowledge in such advanced characterization techniques as transmission electron microscopy, electron energy loss spectroscopy, and FIB micromashining. The expertise generated by this program will be utilized directly in the educational process to teach the current and future scientists/technologists. The PI will organize and carry out scientific seminars, will incorporate new data into the graduate level courses to facilitate the dissemination of knowledge and the developed methodology.