UNS: Nanowire Growth on inductively heated metal films: new reaction diagnostic and pathways towards roll-to-roll processing

UNS：感应加热金属薄膜上的纳米线生长：新的反应诊断和卷对卷加工途径

• 批准号: 1510024
• 负责人: Tobias Hanrath
• 金额: $ 30万
• 依托单位: Cornell University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-06-01 至 2018-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1510024&HistoricalAwards=false
• 关键词: UNS; Nanowire; Growth; inductively; heated

1510024 (Hanrath)Semiconductor nano wires (NWs) are essential building blocks of many emerging nanotechnologies. The technological impact of NWs ranges from energy technologies, optoelectronics, and new applications emerging at the intersection of nano- and biotechnology. In the case of energy storage technologies, silicon nano wires (Si NWs) present one of the most attractive electrode materials for high-capacity lithium ion batteries (LIB). Si NWs are also poised to play a key role in emerging solar energy technologies and have garnered significant interest as electrodes in next-generation photoelectrochemical cells. Beyond energy technologies, NWs also have potential as components in a range of emerging optoelectronic and nanobiotechnologies. Multicolor light emitting diodes (LEDs) have been made possible by controlling the composition of the NW, for example, GaN, CdS, and CdSe, for ultraviolet, visible, and near-infrared emission. Precise control over the NW surface functionalization has enabled the fabrication of NW-based chemical and biosensors, including multiplexed electrical detection of cancer markers and detection of single viruses. Vertical Si NW electrode arrays have also been demonstrated as a promising platform to interface with nerve cells to enable neural prosthetics and studies of neuronal circuits in vivo. To meet the growing expectations generated by the rapid progress with NW prototypes, attention in the field is now shifting to the design of scalable and cost-effective processing methodologies. The scale-up challenge is particularly prominent in battery applications requiring high production volumes; e.g.; a 85 kWh battery for en electric vehicle would require approximately 40 kg of Si NWs for the anode. The approach to fabricate NW devices introduced in this proposal is aimed at advancing that goal. Aside from the technical considerations of NW growth mechanism and fabrication methods, there are also important environmental and health aspects to consider. Due to their small size and high mobility NWs and nanotubes have raised concerns about asbestos-like effects. The NW processing technology developed in this project grows NW directly on the current collector metal; this eliminates separate processing of the NW raw material and mitigates potential exposure steps and facilitates the direct integration into the desired device structure.Intellectual Merit:The proposed research is based on recent discoveries in the PI's lab that Si and Ge NWs can be fabricated on resistively and inductively heated metal surfaces submersed in a fluid precursor environment. This approach provides an opportunity to study outstanding fundamental scientific questions concerning the mechanism and rate-determining step of NW growth. The focus on Si NW growth on Cu films as a model systems is motivated by the technological importance of Si NWs and the prospect of advancing NW processing technique to address outstanding challenges concerning scalable fabrication and device integration. The main objective is to establish the fundamental engineering principles for NW growth on flexible substrates and to enable their processing via roll-to-roll processes. The proposed research is structured along three main aims: to (i) establish the fundamental growth mechanism of NWs grown on heated metal films, (ii) understand the complex interplay between reaction kinetics and precursor transport phenomena and (iii) analyze, design and demonstrate NW growth integrated into a roll-to-roll process. The innovative character of the proposed work is in applying resistive and inductive heating of bulk metal foils as a precisely programmable activation technique to initiate NW growth. The fast dynamic response of the reactor system presents an opportunity to gain new insights into the fundamental thermodynamics and kinetics of NW nucleation and growth. The current-voltage and temperature transients of the heated metal will be investigated as a diagnostic tool to study the dynamics of NW growth. The versatility of the reactor design could provide a foundation to spur advances in other areas of nanostructure formation at heated surfaces.Broader Impacts :The technology in this project could have far-reaching industrial applicability as well as use in medical applications. In addition,the PI will leverage established connections to K-12 programs to develop interactive learning modules. The engagement of high school teachers should have effects in illustrating nano fabrication opportunities and challenges to the next generation of scientists and engineers. The PI will work with the learning lending library of the Cornell Center for Materials Research to make the module freely available to be used in high school science classes nationwide. The educational activities will integrate scientific discoveries into the undergraduate and graduate classrooms by creating a new interdisciplinary design course; this module will provide students with the required skills to conceive, design, and evaluate the feasibility of new fabrication processes and chemical products.

1510024(Hanrath)半导体纳米线(NW)是许多新兴纳米技术的重要组成部分。NWS的技术影响范围从能源技术、光电子学，以及纳米技术和生物技术交汇处出现的新应用。在储能技术方面，硅纳米线是高容量锂离子电池最具吸引力的电极材料之一。硅纳米管还将在新兴的太阳能技术中发挥关键作用，并作为下一代光电化学电池的电极引起了人们的极大兴趣。除了能源技术，核电还具有在一系列新兴的光电子和纳米生物技术中作为组件的潜力。通过控制用于紫外光、可见光和近红外发射的NW的组成，例如GaN、CDS和CdSe，已经使得多色发光二极管(LED)成为可能。对NW表面功能化的精确控制使基于NW的化学和生物传感器的制造成为可能，包括癌症标志物的多路电子检测和单个病毒的检测。垂直的Si NW电极阵列也被证明是一种很有前途的平台，可以与神经细胞对接，从而实现神经假体和体内神经元电路的研究。为了满足对NW原型的快速发展所产生的日益增长的期望，该领域的注意力现在正转移到可扩展和具有成本效益的处理方法的设计上。扩大规模的挑战在需要高产量的电池应用中尤为突出；例如，用于EN电动汽车的85千瓦时电池需要大约40公斤硅纳米钨作为阳极。本提案中介绍的制造NW器件的方法旨在推进这一目标。除了对NW生长机制和制备方法的技术考虑外，还需要考虑重要的环境和健康方面。由于它们的小尺寸和高迁移率，纳米管和纳米管引起了人们对石棉类效应的担忧。在本项目中开发的NW处理技术直接在集电体金属上生长NW；这消除了对NW原材料的单独处理，减少了潜在的曝光步骤，并促进了直接集成到所需的器件结构中。智能优点：拟议的研究基于PI实验室的最新发现，即可以在浸没在流体前体环境中的电阻和感应加热的金属表面上制造Si和Ge NW。这种方法提供了一个机会来研究有关西北增长机制和速率决定步骤的悬而未决的基础科学问题。作为一个模型系统，人们关注于在铜薄膜上生长Si NW，是因为Si NW的技术重要性以及发展NW工艺技术以解决可扩展制造和器件集成方面的突出挑战的前景。主要目标是建立柔性衬底上NW生长的基本工程原理，并通过卷到卷的工艺实现它们的加工。建议的研究围绕三个主要目标进行：(I)建立在加热的金属薄膜上生长NW的基本机制，(Ii)了解反应动力学和前体传输现象之间的复杂相互作用，以及(Iii)分析、设计和演示集成到卷到卷过程中的NW生长。这项工作的创新之处在于将块状金属箔的阻性加热和感应加热作为一种精确可编程的激活技术来启动NW生长。反应堆系统的快速动态响应提供了一个机会，使我们有机会对NW形核和生长的基本热力学和动力学有新的见解。被加热金属的电流-电压和温度瞬变将被作为研究NW生长动力学的诊断工具。反应堆设计的多功能性可以为促进在加热表面形成纳米结构的其他领域的进步提供基础。广泛的影响：该项目中的技术可能具有深远的工业适用性，以及在医疗应用中的应用。此外，PI将利用已建立的与K-12课程的联系来开发互动学习模块。高中教师的参与应该会对说明纳米制造给下一代科学家和工程师带来的机会和挑战产生影响。PI将与康奈尔材料研究中心的学习借阅图书馆合作，免费提供该模块，供全国高中科学课堂使用。教育活动将通过创建一门新的跨学科设计课程，将科学发现融入本科生和研究生的课堂；该模块将为学生提供构思、设计和评估新制造工艺和化学产品的可行性所需的技能。