FRG: Morphological Electronic and Chemical Structure of Lattice-Mismatched III-V Heterojunctions

FRG：晶格失配 III-V 异质结的形态电子结构和化学结构

• 批准号: 0076362
• 负责人: Leonard Brillson
• 金额: $ 96.24万
• 依托单位: Ohio State University Research Foundation -DO NOT USE
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-09-01 至 2004-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0076362&HistoricalAwards=false
• 关键词: FRG; Morphological; Electronic; Chemical; Structure

This FRG project involves a cross-disciplinary group of PIs to explore underlying properties that dictate ultimate device-viability of lattice-mismatched heterojunctions. Lattice mismatch not only determines the growth morphology but also affects thermodynamic stability, creation of localized electronic states, and transport barriers at band edge discontinuities. Techniques for lattice matching lattice-mismatched materials can manipulate electronic and optical properties on an atomic scale. Control of these issues may remove constraints imposed by standard materials (e.g., GaAs and InP) on the functionality attainable from the full range of semiconductor materials. The perceived challenges are to achieve planar growth and thermal compatibility with simultaneous control of mechanical, chemical, and electronic structure. The inter-relationships between these properties and growth parameters must be understood at a fundamental level to achieve significantly greater utilization of lattice-mismatched heterostructures. The project strives to not only understand each set of properties, but also to discover how they result from specific variations in growth conditions. The approach incorporates (i) growth by molecular beam epitaxy (MBE), (ii) direct measurement of the atomic structure of the created materials, (iii) in-situ and ex-situ measurements of electronic, atomic-scale and optical properties, and (iv) theoretical calculations of electronic structure of the actual materials. A few model systems based on III-V compounds were chosen both for the technological importance of these material systems in advanced devices and as precisely controlled sample sets necessary to interpret the measurements and calculations. The project focus is primarily on InAlAs, InGaAs and InAsP mismatched heterostructures grown on InP, InGaP and InAlP grown on GaAs, and a few choice binary combinations of varying misfit to provide precisely controlled measurement data for correlation with theoretical calculations of properties. %%%The project addresses basic research issues in a topical area of materials science with high technological relevance. The project builds on recent advances in representative heterojunction systems, while adding new capabilities for characterizing electronic properties of mismatched films as they evolve with growth. The basic knowledge and understanding gained from the research is expected to contribute to improving semiconductor materials performance in current and future device and circuit applications. An important feature of the program is the integration of research and education through the training of students in a fundamentally and technologically significant area. The multidisciplinary (materials science, electrical engineering, physics) nature of this FRG project offers unique educational opportunities for students to experience a teamwork-oriented research environment. ***

这个FRG项目涉及一个跨学科的PI小组，以探索决定晶格失配异质结最终器件可行性的潜在特性。晶格失配不仅决定了生长形态，还影响热力学稳定性、局域电子态的产生以及带边不连续处的输运垒。晶格失配材料的晶格匹配技术可以在原子尺度上操纵电子和光学性质。控制这些问题可以消除标准材料施加的限制（例如，GaAs和InP）对从全系列半导体材料可获得的功能的影响。所感知的挑战是实现平面生长和热兼容性，同时控制机械，化学和电子结构。这些属性和生长参数之间的相互关系必须在一个基本的水平上理解，以实现更大的利用晶格失配异质结构。该项目不仅致力于了解每一组属性，而且还试图发现它们是如何从生长条件的特定变化中产生的。该方法包括（i）通过分子束外延（MBE）生长，（ii）直接测量所创建材料的原子结构，（iii）电子、原子尺度和光学性质的原位和非原位测量，以及（iv）实际材料的电子结构的理论计算。选择了一些基于III-V族化合物的模型系统，这既是因为这些材料系统在先进设备中的技术重要性，也是因为它们是解释测量和计算所需的精确控制的样品集。该项目的重点主要是在InP上生长的InAlAs，InGaAs和InAsP失配异质结，在GaAs上生长的InGaP和InAlP，以及几个选择不同失配的二元组合，以提供精确控制的测量数据与理论计算的属性。该项目解决了材料科学领域的基础研究问题，具有高度的技术相关性。该项目建立在代表性异质结系统的最新进展的基础上，同时增加了表征失配薄膜随着生长而演变的电子特性的新能力。从研究中获得的基本知识和理解预计将有助于改善当前和未来器件和电路应用中的半导体材料性能。该计划的一个重要特点是通过在一个基本和技术上重要的领域对学生进行培训来整合研究和教育。该FRG项目的多学科（材料科学，电气工程，物理学）性质为学生提供了独特的教育机会，体验以团队合作为导向的研究环境。***