Atomistic Control over Functional Defects in van der Waals Nanostructures

范德华纳米结构功能缺陷的原子控制

• 批准号: 2315397
• 负责人: Eli Sutter
• 金额: $ 54.29万
• 依托单位: University of Nebraska-Lincoln
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-01 至 2026-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2315397&HistoricalAwards=false
• 关键词: Atomistic; Control; over; Functional; Defects

Part 1: Non-Technical Summary Imperfections (defects) in materials have traditionally been seen as undesirable, especially in electronic materials such as semiconductors. Hence, efforts in science and engineering have focused on eliminating defects in materials for technological applications. With support from the Solid State and Materials Chemistry program in the Division of Materials Research, Profs. Eli and Peter Sutter and their groups at the University of Nebraska pursue a fundamentally different approach, namely to (i) identify possible mechanisms by which specific defects can be generated during materials synthesis; (ii) determine ways of controlling the placement and type of the imperfection in its host crystal; and (iii) uncover the properties emerging from such controlled defects. To realize this vision, the project focuses on a particular class of materials, layered crystals consisting of atomically thin sheets held together by weak van der Waals forces, as well as a "vapor-liquid-solid" synthesis process that promises manifold opportunities for manipulating single defects. If successful, the research could fundamentally change our view of defects in electronic materials, with potentially transformative impact in basic science as well as key sectors of technology. In addition to pursuing these technical objectives, the project provides far-reaching opportunities for training and career development to the participating students. And it aims to help enhance education, diversity, and the participation of underrepresented groups – in particular girls from rural and Native American tribal communities – in Science, Technology, Engineering, and Math (STEM) by organizing annual summer workshops for student/teacher teams from rural Nebraska communities and by developing microprocessor-based teaching aids for use in middle- and high school science classrooms.Part 2: Technical SummaryDefects have traditionally been perceived as detrimental (and thus undesirable) in electronic and functional materials. Recent research showed that point defects may provide important new functionality, e.g., for quantum information processing. Extended defects could similarly harbor emerging properties of interest for technology, but identifying and ultimately harnessing functionality from extended defects faces major challenges, including the development of synthesis protocols with innate control over defect placement, orientation, and configuration; and the positioning of tailored single defects in a small host volume so that the defect dominates the overall properties. This project supported by the Solid State and Materials Chemistry program in the NSF’s Division of Materials Research addresses these challenges by taking advantage of opportunities presented by the reduced symmetry of van der Waals crystals and by developing vapor-liquid-solid nanostructure growth processes to obtain a fundamental understanding of extended defect formation and tuning combined with measurements of emerging properties such as electronic structure, optoelectronics, charge transport, and ferroelectricity. Specifically, the research will examine the materials chemistry underlying the formation of defects such as dislocations and stacking faults in nanostructures of layered monochalcogenide semiconductors, their alloys, as well as axial and radial heterostructures. And it aims to identify approaches for transcribing tailored defects into a wide range of other materials, including other layered crystals and conventional 3D-crystalline semiconductors. This will set the stage for systematically exploring the emerging properties of tailored individual line and planar defects in a wide range of nanostructured materials. The successful realization of the project goals could pave the way for a paradigm shift toward the pursuit of crystalline materials where new functionality emerges from single defects with controlled properties.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

第 1 部分：非技术总结 传统上，材料中的缺陷（缺陷）被认为是不受欢迎的，尤其是在半导体等电子材料中，因此，在技术应用的支持下，科学和工程领域的努力一直集中在消除材料中的缺陷。内布拉斯加大学材料研究部的固态和材料化学项目，Eli 和 Peter Sutter 教授及其团队采用了一种根本不同的方法，即 (i) 确定材料在加工过程中产生特定缺陷的可能机制。合成；（ii）确定控制其主体晶体中缺陷的位置和类型的方法；以及（iii）揭示此类受控缺陷所产生的特性，该项目重点关注一类特定的材料，即分层材料。由弱范德华力结合在一起的原子薄片组成的晶体，以及“气-液-固”合成过程，有望为操纵单一缺陷提供多种机会。如果成功，这项研究可能会从根本上改变我们对缺陷的看法。电子材料，与除了追求这些技术目标外，该项目还为参与的学生提供了深远的培训和职业发展机会，旨在帮助加强教育、多样性和职业发展。通过为内布拉斯加州农村社区的学生/教师团队组织年度夏季研讨会以及开发基于微处理器的教学，让代表性不足的群体（特别是来自农村和美洲原住民部落社区的女孩）参与科学、技术、工程和数学 (STEM)中、高年级使用的辅助工具学校科学课堂。第 2 部分：技术摘要电子和功能材料中的缺陷传统上被认为是令人痛苦的（因此是不受欢迎的）。最近的研究表明，点缺陷可能提供重要的新功能，例如，对于量子信息处理来说，扩展缺陷同样可能存在。技术感兴趣的新兴特性，但识别并最终利用扩展缺陷的功能面临着重大挑战，包括开发对缺陷放置、方向和配置进行固有控制的合成协议，以及在小主机体积中定位定制的单个缺陷；以便该项目由美国国家科学基金会材料研究部的固态和材料化学项目支持，通过利用范德华晶体对称性降低和开发气液-缺陷所带来的机会来解决这些挑战。固体纳米结构生长过程，以获得对扩展缺陷形成和调整的基本了解，并结合电子结构、光电子学、电荷传输和铁电性等新兴特性的测量。具体来说，该研究将研究其背后的材料化学。层状单硫族化物半导体及其合金以及轴向和径向异质结构的纳米结构中缺陷的形成，例如位错和堆垛层错，其目的是确定将定制缺陷转录到各种其他材料中的方法，包括其他层状晶体和材料。这将为系统地探索各种纳米结构材料中定制的单独线和平面缺陷的新兴特性奠定基础。该项目的目标可以为追求晶体材料的范式转变铺平道路，其中新功能是从具有受控特性的单一缺陷中产生的。该奖项反映了使命，并通过使用基金会的智力优点和更广泛的影响进行评估，被认为值得支持审查标准。