Metal Semiconductor Interface Growth Using Electrochemical Atomic Layer Deposition (ALD)

技术：该项目旨在进一步了解和演示电化学原子层沉积（ALD）在环境条件下（水溶液）形成高质量的固态纳米结构。电化学ALD是一种表面受限的电化学反应，如欠电位沉积（UPD）用于ALD。金属和半导体固体界面：金属/金属、半导体/金属、金属/半导体和半导体/半导体，将在原子层之间形成，并在ALD生长过程中使用表面科学方法进行表征。预期的结果是扩大对电化学ALD的理解，以及关于哪些材料可以生长、在哪些衬底上生长和质量如何的实用信息。研究一种新型的电化学表面限制反应，即表面限制氧化还原替代（SLRR），允许金属ALD的形成，也将采用超高真空（UHV）表面分析技术（如LEED， Auger和XPS）来探索界面的形成。原位STM将用于跟踪表面原子结构。纳米结构的形成将在薄层流动电沉积系统中进行，并使用电化学石英晶体微平衡（EQCM）流动电池系统和原位STM流动电池系统进行原位表征。界面是层状电子和光子材料的主要组成部分，因此可以是原子和电子结构的决定因素。对固态界面逐层生长的研究主要局限于超高真空、高温条件下的分子束外延（MBE）。这些研究将是第一次系统地研究金属和半导体固体界面在室温下在水溶液中形成时的逐层生长。非技术：该项目涉及材料科学中具有高技术相关性的主题领域的基础研究问题，并期望为研究生和本科生在材料科学，化学和表面物理的跨学科研究方面提供独特的培训机会。这个项目的教育影响涉及到研究生、本科生和高中预科的少数民族学生。PI在与少数民族打交道方面有着良好的记录，他教过6名少数民族本科生，有6名少数民族研究生，其中两名目前在他的小组里，还有两名已经在研究机构担任教职。在高中前阶段，PI已经开始了一项名为“科学鼓专业”（DMS）的计划，旨在将科学引入以少数民族为主的小学，在他们进入初中和高中之前，在他们仍然对科学感兴趣的时候抓住年轻学生的思想。他计划将教师、研究生和本科生纳入到重复访问中。报告将包括简短的幻灯片讲座、演示、动手实验和一般的问答时间，以激发和鼓励学生的好奇心。

Technical: This project aims for further understanding and demonstration of electrochemical atomic layer deposition (ALD) for the formation of high quality solid state nanostructures under ambient conditions (aqueous solutions). Electrochemical ALD is where surface limited electrochemical reactions such as underpotential deposition (UPD) are used for ALD. Metal and semiconductor solid state interfaces: metal/metal, semiconductor/metal, metal/semiconductor, and semiconductor/semiconductor, will be formed atomic layer by atomic layer and characterized during ALD growth using surface science methodologies. Outcomes expected are an expanded understanding of electrochemical ALD, and practical information about which materials can be grown, on which substrates and with what quality. The study of a new type of electrochemical surface limited reaction, surface limited redox replacement (SLRR), allowing ALD formation of metals will also be pursued to explore interface formation using ultra high vacuum (UHV) surface analysis techniques such as LEED, Auger, and XPS. In-situ STM will be used to follow surface atomic structure. Nanostructure formation will be performed in a thin layer flow electrodeposition system, and characterized in-situ using an electrochemical quartz crystal microbalance (EQCM) flow cell system, as well as using an in-situ STM flow cell system. Interfaces are a primary component of layered electronic and photonic materials, and thus can be atomic and electronic structure determining factors. Studies of the layer by layer growth of solid state interfaces has been limited primarily to molecular beam epitaxy (MBE), in ultrahigh vacuum, at high temperatures. These studies will be the first systematic investigations of layer by layer growth of metal and semiconductor solid state interfaces as they form in aqueous solutions at room temperature. Non-technical: The project addresses basic research issues in a topical area of materials science with high technological relevance, and is expected to provide unique opportunities for graduate and undergraduate student training in interdisciplinary research across materials science, chemistry, and surface physics. Educational impacts of this project involve minority students at the graduate, undergraduate, and pre high school levels. The PI has an established record of working with minorities, having taught six minority undergraduate students, and had six minority graduate students, two of which are currently in his group, and two have gone on to faculty positions at research institutions. At the pre high school level, the PI has begun a program 'Drum Majors for Science' (DMS) designed to bring science into predominantly minority elementary schools to capture the minds of young students while they are still interested in science, before they move on through middle and High school. He plans to incorporate faculty, graduate, and undergraduate students in repeated visits. Presentations are to involve short power point lectures, demonstrations, hands on experiments, and general question and answer time to stimulate and encourage student curiosity.