Doping in Non-Planar Heterostructures

非平面异质结构中的掺杂

• 批准号: 1308654
• 负责人: Lincoln Lauhon
• 金额: $ 38.08万
• 依托单位: Northwestern University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-09-01 至 2016-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1308654&HistoricalAwards=false
• 关键词: Doping; Non; Planar; Heterostructures

Technical Description: Non-planar heterostructures, particularly core-shell nanowires, exhibit a number of comparative advantages for optoelectronic applications with respect to conventional planar heterostructures. The analysis of dopant distribution and interface morphology is extremely challenging, however, limiting the understanding of fundamental growth processes that is needed to optimize the structure and properties. This project investigates the driving forces that control dopant and alloy element incorporation, diffusion, and segregation in non-planar heterostructures consisting of both Si-Ge and GaAs-AlGaAs core-shell nanowires. To this end, atom probe tomography, Hall effect measurements, Kelvin probe force microscopy, and micro-photoluminescence are used to relate doping levels, and fluctuations in composition, to electronic and optical properties. Numerical modeling of dopant diffusion during processing and electrical transport in device structures is based on and compared with quantitative, atomic scale composition information provided by the atom probe studies.Non-technical Description: New materials, and conventional materials in new forms, can improve existing technologies and lead to the creation of new technologies. This project is developing a fundamental understanding of how known semiconductor materials, such as silicon and gallium arsenide, can be put together in new ways to better perform important functions, such as the efficient conversion of light to electrical energy and vice versa. The research activity is specifically focused on non-planar heterostructures, where "heterostructure" indicates the combination of two distinct materials and "non-planar" indicates that the junction between these materials has a complex three-dimensional form so as to better carry out key device functions. To analyze the shape of non-planar heterostructures and the distribution of tiny quantities of charge-controlling dopant atoms within them, a highly specialized microscope known as an atom probe tomographic is employed. The atom probe can look inside the very smallest devices that have ever been made and map out the distribution of all the elements that are present. The project incorporates an industrial perspective on the development of materials for new technologies by including a "co-op on campus" program, in which undergraduate research projects of relevance to the larger goals of the research are solicited from industrial partners.

技术描述：非平面异质结构，尤其是核心壳纳米线，在传统的平面异质结构方面具有光电应用的许多比较优势。但是，对掺杂剂分布和界面形态的分析极具挑战性，但是限制了对优化结构和特性所需的基本增长过程的理解。该项目研究了由SI-GE和GAAS-ALGAAS CORE-SHELL纳米线组成的非平面异质结构中控制掺杂剂和合金元素掺入，扩散和隔离的驱动力。为此，原子探针断层扫描，霍尔效应测量，开尔文探针力显微镜和微透明发光用于将掺杂水平以及组成的波动与电子和光学特性相关联。设备结构中的掺杂剂扩散的数值模型是基于原子探针研究提供的定量，原子量表组成信息的基础，并将其与新形式的新材料和新形式的常规材料进行比较，可以改善现有技术并导致创建新技术。该项目正在对已知的半导体材料（例如硅和砷化凝胶）进行基本了解，以新的方式将其放在一起，以更好地执行重要功能，例如将光的有效转化为电能，反之亦然。研究活动专门集中在非平面异质结构上，其中“异质结构”表明两种不同的材料和“非平面”的组合表明这些材料之间的连接具有复杂的三维形式，以便更好地执行关键设备功能。为了分析非平面异质结构的形状以及其中的小量控制掺杂剂原子的分布，采用了一种高度专业的显微镜，称为原子探针断层扫描。原子探针可以看一下制造有史以来最小的设备，并绘制出存在的所有元素的分布。该项目通过包括一个“校园合作社”计划，其中包含了有关新技术材料开发的工业视角，在该计划中，本科研究项目与研究的更大目标是从工业合作伙伴中征求的。