Ion beams: creating functionalities and probing interfaces in materials

离子束：在材料中创建功能和探测界面

• 批准号: RGPIN-2020-06679
• 负责人: Goncharova, Lyudmila
• 金额: $ 2.04万
• 依托单位: University of Western Ontario
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=762984
• 关键词: Ion; beams; creating; functionalities; probing

The central theme of my proposed research is unravelling the mystery of materials on the electronic level, with focus on quantum structures and other nanoscale materials, with the electronic properties modified from their bulk analogues. My group studies atomic-scale behavior of semiconductor quantum dots (QD) with emphasis on their interfaces. Advanced fabrication methods such as ion beam modification (IBM) and molecular beam epitaxy (MBE) combined with nanofabrication are used. Surface and interface characterization tools with sub-nanometer depth resolution, and the atomic lateral resolution as well as time-domain optical spectroscopy are employed. Three major themes will be pursued in the next five years: 1. Semiconductor quantum structures: interplay of quantum confinement, interface and defect states. We have established expertise in the fabrication of silicon QDs using ion beams and will further explore the difference in optical and electronic properties of these systems when doped. We are interested in the interactions of photons (visible or X-ray) with these QD assemblies studied using photoluminescence (PL), time-resolved PL and X-ray excited optical luminescence (XEOL). Special effort will be given to characterization of the QDs/matrix interfaces and description of the transport properties using various transport models. These studies will be extended to device response under non-equilibrium conditions, e.g., with applied voltage or under illumination. The results of this work will have immediate impact on semiconductor science and technology, light-emitting structures and the future generation of ultra-fast devices for signal transmission and processing. 2. Plasmonic effects. Our goal is to achieve controllable plasmonic responses for metal nanoparticles (Al, Au) and non-metal group IV plasmonic systems. By using MBE and IBM, we will design and fabricate plasmonic structures that will be optimized to operate in the UV/visible and short wavelength IR range. We will focus on the following key questions. Can plasma frequency be controlled through MBE growth combined with nanofabrication and IBM? What are the effects of geometry on plasmonic structures? How to better control the confined modes? The outcome of these studies will be applicable in quantum and chemical sensing. 3. Ultra-high resolution ion depth profiling and in-situ capabilities. We will focus on in-situ application of high-resolution ion beam analysis to electrochemical processes. New in-situ devices will be designed and employed to study the mechanisms of passive film growth on metals, corrosion in multilayer metal structures and interface effects in Li- and Na-ion batteries. New designs of in-situ cells give us opportunities to perform high-resolution depth analysis while cycling the electrochemical cells. An improved understanding of reaction mechanisms will lead to higher performance of electrodes, better passive films, more advanced corrosion protection.

我提出的研究的中心主题是在电子水平上揭开材料的神秘面纱，重点是量子结构和其他纳米级材料，其电子特性是根据其块状类似物进行修改的。我的小组研究半导体量子点 (QD) 的原子尺度行为，重点研究其界面。采用离子束改性 (IBM) 和分子束外延 (MBE) 等先进制造方法与纳米加工相结合。采用具有亚纳米深度分辨率、原子横向分辨率以及时域光谱的表面和界面表征工具。未来五年将追求三大主题： 1. 半导体量子结构：量子限制、界面和缺陷态的相互作用。我们已经在使用离子束制造硅量子点方面建立了专业知识，并将进一步探索这些系统在掺杂时光学和电子特性的差异。我们对光子（可见光或 X 射线）与使用光致发光 (PL)、时间分辨 PL 和 X 射线激发光学发光 (XEOL) 研究的这些 QD 组件的相互作用感兴趣。我们将特别致力于量子点/矩阵界面的表征以及使用各种传输模型的传输特性的描述。这些研究将扩展到非平衡条件下的器件响应，例如施加电压或光照下。这项工作的成果将对半导体科学技术、发光结构以及下一代用于信号传输和处理的超高速器件产生直接影响。 2.等离子体效应。我们的目标是实现金属纳米颗粒（Al、Au）和非金属 IV 族等离子体系统的可控等离子体响应。通过使用MBE和IBM，我们将设计和制造等离子体结构，该结构将被优化以在紫外/可见光和短波长红外范围内运行。我们将重点关注以下几个关键问题。能否通过 MBE 生长结合纳米加工和 IBM 来控制等离子体频率？几何形状对等离子体结构有什么影响？如何更好地控制受限模式？这些研究的成果将适用于量子和化学传感。 3. 超高分辨率离子深度分析和原位功能。我们将重点关注高分辨率离子束分析在电化学过程中的原位应用。将设计和采用新的原位装置来研究金属上钝化膜生长的机制、多层金属结构的腐蚀以及锂离子和钠离子电池的界面效应。原位电池的新设计使我们有机会在循环电化学电池时进行高分辨率深度分析。对反应机制的深入了解将带来更高性能的电极、更好的钝化膜和更先进的腐蚀保护。