Engineering Interfaces in No-Common-Atom Heterostructures

非共原子异质结构中的工程接口

• 批准号: 0412736
• 负责人: Roy Clarke
• 金额: $ 11.93万
• 依托单位: Regents of the University of Michigan - Ann Arbor
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-09-01 至 2006-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0412736&HistoricalAwards=false
• 关键词: Engineering; Interfaces; No; Common; Atom

A one-year program of research is proposed on the synthesis and atomic level characterization of short period superlattices (SPS) in which the constituent layers do not share a common element. These no-common-atom systems, such as InAs/GaSb, have attracted significant interest for applications in infrared optoelectronics technology, offering the possibility to tune electronic band structure by manipulating the low-symmetry interface structure. The goal is to achieve understanding of the epitaxial growth conditions and processes required to synthesize no-common-atom SPS with well-defined interface structures. This calls for a high level of control over atomistic mechanisms of interface formation and the ability to characterize the interface structure with atomic resolution. A unique feature of the project is the use of a novel direct method to image buried interfaces using x-ray synchrotron radiation. This technique, Coherent Bragg Rod Analysis (COBRA), is capable of providing, non-destructively, a three-dimensional map of epitaxial thin-film structures with sub-Angstrom resolution of atomic positions. COBRA maps will be used to seek sufficiently detailed structural and compositional information to control growth conditions enabling specific interface structures with tailored optoelectronic properties. Theoretical predictions of the interface composition distributions are available with which experimentally determined interface structures can be compared. These kinetic models will serve as a useful guide for experiments. %%% The project addresses basic research issues in a topical area of electronic materials with high technological relevance. The tunability of electronic properties inherent in no-common-atom short period superlattices (SPS) systems may impact infrared device technology in areas where there are important societal needs, for example in health care, communications, and national security. An important element of the project is the integration of research and education through the training of students in a fundamental and technologically significant area. The project offers exciting research opportunities for graduate training and also for more junior students to become interested in science and engineering. A program of research activities which are integrated with the proposed research, but which are also accessible to less experienced students has been devised. The use of national research facilities (Advanced Photon Source) will expose students to forefront programs in materials research, and provide opportunities to network with a broad range of educational and training activities in different fields. The U. MI joint Beam Line Sector with Howard University at the Advanced Photon Source is a focal point for encouraging research participation of students from underrepresented groups. ***

提出了为期一年的研究计划，该计划涉及短期超晶格（SP）的合成和原子水平表征，其中组成层不具有共同元素。这些无通用原子系统（例如INAS/GASB）对红外光电技术的应用引起了重大兴趣，从而通过操纵低对称性界面结构来调整电子带结构的可能性。目的是了解与具有明确定义的界面结构合成无常见原子SP所需的外延生长条件和过程。这要求对界面形成的原子机制进行高水平的控制，并具有通过原子分辨率表征界面结构的能力。该项目的一个独特特征是使用一种新型的直接方法使用X射线同步子辐射来掩埋界面。该技术是连贯的bragg杆分析（COBRA），能够在非毁灭性上提供三维外延薄膜结构的图，具有原子位置的亚角分辨率。眼镜蛇地图将用于寻求足够详细的结构和组成信息，以控制生长条件，从而实现具有定制光电特性的特定界面结构。可以通过比较实验确定的界面结构的界面组成分布的理论预测。这些动力学模型将作为实验的有用指南。 %%％该项目解决了具有高技术相关性的电子材料主题领域的基础研究问题。在不常见原子短期超晶格（SPS）系统中固有的电子属性的可调节性可能会影响有重要社会需求的领域的红外设备技术，例如医疗保健，通讯和国家安全。该项目的重要组成部分是通过在基本和技术意义的领域中培训学生来整合研究和教育。该项目为研究生培训提供了令人兴奋的研究机会，还为更多的初级学生对科学和工程感兴趣。与拟议的研究集成在一起的研究计划，但已经设计了经验不足的学生。国家研究设施的使用（高级光子来源）将使学生进入材料研究中的最前列计划，并为在不同领域提供广泛的教育和培训活动提供机会。美国与霍华德大学在高级光子源的联合束线领域是鼓励来自代表性不足的群体的学生参与的焦点。 ***