Materials World Network: Novel Strain Control in Thick Epitaxial Nancomposite Films

材料世界网络：厚外延纳米复合材料薄膜中的新型应变控制

• 批准号: 0709831
• 负责人: Haiyan Wang
• 金额: $ 27万
• 依托单位: Texas A&M Engineering Experiment Station
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-09-01 至 2011-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0709831&HistoricalAwards=false
• 关键词: Materials; World; Network; Novel; Strain

This Materials World Network project explores the growth, structure and physical properties of vertically strain-controlled nanocomposite (VSCN) systems in epitaxial thin film form. The proposed research opens the door to a brand-new avenue for lattice strain control in two-phase nanocomposites, whereby the nanocolumns control the strain vertically in one another, independent of the interface. The elimination of interface control in the VSCN systems allows much thicker strained films (300 nm) to be grown compared to lateral heteroepitaxial systems and thus allows a whole range of novel functional device possibilities. This project involves extensive collaboration between Texas A & M University (Dr. Wang) and the University of Cambridge (Dr. Driscoll) in the United Kingdom.The goal of this joint program is to grow and understand VSCN epitaxial films for novel applications. The objectives include: 1) to develop a set of guidelines for predicting possible 2-phase nancomposite systems; 2) to utilize complementary deposition techniques to grow films of the predicted systems; 3) to determine the factors which control the VSCN architectures; and 4) to demonstrate one or two single phase property enhancements or novel multifunctionalities. This interdisciplinary effort combines research expertise from both universities. Novel VSCN systems will first be explored using chemical vapor deposition, CVD (Cambridge) and then, pulsed laser deposition, PLD (Texas). Various characterization techniques, such as high resolution XRD (Cambridge) and TEM (combined with STEM and EELS compositional analysis, Texas), as well as electrical and magnetic property measurements, will be utilized to investigate the structural, and functional properties of these VSCN systems. The intellectual merit of the proposed research is the fundamental understanding of vertical strain-control in VSCN systems, which allows growth of strained layers far in excess of the conventional critical thickness. The project will have broad impact by 1) offering international multidisciplinary training to the researchers involved in the program and 2) enhancing the materials science and engineering curricula at both universities. The research results will be quickly disseminated to a much broader audience by (a) involving high school teachers in this research project, (b) involving under-represented groups in materials science and engineering and (c) attracting high school students into Materials Science program through the outreach programs available at both universities.

该材料世界网络项目探索外延薄膜形式的垂直应变控制纳米复合材料（VSCN）系统的生长、结构和物理性质。这项研究为两相纳米复合材料中晶格应变控制开辟了一条全新途径，其中纳米柱可以独立于界面而相互垂直控制应变。与横向异质外延系统相比，VSCN 系统中消除了界面控制，可以生长更厚的应变薄膜（300 nm），从而实现一系列新颖功能器件的可能性。该项目涉及德克萨斯农工大学（王博士）和英国剑桥大学（Driscoll 博士）之间的广泛合作。该联合项目的目标是生长和了解 VSCN 外延薄膜的新颖应用。目标包括：1）制定一套用于预测可能的两相纳米复合材料系统的指南； 2）利用互补沉积技术来生长预测系统的薄膜； 3）确定控制VSCN架构的因素； 4) 展示一种或两种单相性能增强或新颖的多功能性。这项跨学科的努力结合了两所大学的研究专业知识。新型 VSCN 系统将首先使用化学气相沉积 CVD（剑桥）进行探索，然后使用脉冲激光沉积 PLD（德克萨斯州）。各种表征技术，例如高分辨率 XRD（剑桥）和 TEM（与德克萨斯州的 STEM 和 EELS 成分分析相结合）以及电学和磁学特性测量，将用于研究这些 VSCN 系统的结构和功能特性。 该研究的智力价值在于对 VSCN 系统中垂直应变控制的基本理解，该系统允许应变层的生长远远超过传统的临界厚度。该项目将通过以下方式产生广泛影响：1）为参与该项目的研究人员提供国际多学科培训；2）加强两所大学的材料科学和工程课程。研究成果将通过以下方式迅速传播给更广泛的受众：（a）让高中教师参与该研究项目，（b）让材料科学与工程领域代表性不足的群体参与进来，以及（c）吸引高中生加入材料科学项目通过两所大学提供的外展计划。