Collaborative Research: Transport Imaging of Semiconductor Nanowires

合作研究：半导体纳米线的传输成像

• 批准号: 0804646
• 负责人: Roya Maboudian
• 金额: $ 25.71万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-07-01 至 2013-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0804646&HistoricalAwards=false
• 关键词: Collaborative; Research; Transport; Imaging; Semiconductor

Technical: This project combines VLS (vapor-liquid-solid) growth/processing of bridged SiC and Si nanowires with a nanoscale imaging technique to study relationships between synthesis, processing, and contact/transport behavior. Transport imaging combines the scanning resolution of near field optics with the charge generation beam control of a scanning electron microscope (SEM). A goal is to "image transport" by monitoring the motion of charge via the recombination emission of light. The technique builds upon standard cathodoluminescence (CL), but is significantly different, since it maintains spatial information of the emitted light, which allows for direct measurement of spatially resolved minority carrier diffusion, mobility-lifetime products under applied fields, and contact resistance--parameters otherwise difficult to measure on a single nanowire. The project aims to take this imaging to the ~ 50-100 nm scale with the use of an atomic force microscope (AFM)/near field scanning optical microscope (NSOM) operating inside an SEM. By decoupling the e-beam excitation from the optical collection, one can image transport of charge over distances from ~ 100 nm to microns along wire lengths. A Nanonics MultiView 2000 system will be used, which allows for independent scanning of fiber tip or sample. Measurements will be performed on individually bridged SiC and Si nanowires, as well as ZnO and GaN wires. VLS nanowire synthesis/processing research is an integral part of the collaborative research. This technique has been successfully demonstrated for the growth of solid whiskers and nanowires; bridged growth has been demonstrated within silicon microtrenches. The bridged structures have been found to make rigid connections to the receiving side of the trench, making them of interest for large scale device fabrication. They also provide ideal structures for application of external bias for transport imaging. Specific goals include 1) demonstration of direct transport imaging in semiconductor nanowires, 2) transport measurements as a function of nanowire diameter, 3) measurement of contact resistance and carrier injection, 4) study of the role of VLS process catalyst and surface passivation on optical and transport properties. Non-technical: The project addresses basic research issues in a topical area of electronic/photonic materials science with high technological relevance. Additionally, the project provides education and training for three graduate students and a minimum of 6-8 undergraduate and high school students. NPS educates active duty officers in all branches of the US forces, as well as students from 30+ countries. The students reflect the full diversity of the US active duty force and many take their technical education into positions of leadership in the regular workforce upon completion of their service. A UC Berkeley graduate student will work in collaboration, and UCB will take advantage of its SUPERB ((Summer Undergraduate Program in Engineering Research at Berkeley) program to involve undergraduate and summer students. Special emphasis will be placed on recruitment of women and underrepresented students. Both PIs have strong records of mentoring women and underrepresented groups and have been active in undergraduate and K-12 outreach. The results will be disseminated through publication and presentation, as well as public outreach venues at both NPS and UCB.

技术：该项目将桥接SIC和SI纳米线的VLS（蒸气 - 液体固体）与纳米级成像技术结合在一起，以研究合成，加工和接触/传输行为之间的关系。传输成像结合了近场光学器件的扫描分辨率与扫描电子显微镜（SEM）的电荷产生光束控制。一个目标是通过通过光的重组发射监测电荷的运动来“图像传输”。该技术建立在标准的阴极发光（CL）的基础上，但有显着差异，因为它保持了发射光的空间信息，从而可以直接测量空间分辨的少数载体扩散，在应用领域中持续性的产物，并且在施加的磁场下产生了移动性，并且可以在单个NanoWire上进行诸如单个NanoWire的参数测量。该项目旨在通过使用原子力显微镜（AFM）/近场扫描光学显微镜（NSOM）将该成像降低到50-100 nm量表。通过将电子束激发与光学集合解耦，可以在沿线长度沿从〜100 nm到微米的电荷的电荷传输。将使用纳米学多视期2000系统，该系统允许对纤维尖端或样品进行独立扫描。测量将对单独桥接的SIC和SI纳米线以及ZnO和GAN电线进行测量。 VLS纳米线合成/加工研究是协作研究的组成部分。该技术已成功证明了固体晶须和纳米线的生长。在硅微晶格中已经证明了桥接生长。已经发现桥接的结构可以与沟槽的接收侧建立刚性的连接，从而使它们对大型设备制造很感兴趣。它们还提供了用于运输成像外部偏见的理想结构。具体目标包括1）在半导体纳米线中进行直接运输成像的演示，2）传输测量作为纳米直径的函数，3）测量接触电阻​​和载体注入的测量，4）研究VLS过程催化剂和光学和运输特性的VLS过程催化剂和表面厌氧的作用。非技术：该项目解决了具有高技术相关性的电子/光子材料科学主题领域的基础研究问题。此外，该项目为三名研究生提供教育和培训，至少有6-8名本科生和高中生。 NP在美军所有分支机构以及来自30多个国家 /地区的学生中教育现役官员。学生们反映了美国现役军队的全部多样性，许多人在完成服务后将其技术教育置于常规劳动力中的领导地位。 UC伯克利分校的研究生将合作，UCB将利用其出色的（（伯克利的夏季本科课程）计划，涉及本科生和夏季学生。将特别强调招募妇女和少数人的妇女和不足的妇女和不足的成员的招募和不足的成员。通过出版和演讲以及NPS和UCB的公共外展场所进行传播。