Control and Manipulation of Polarization and Electric Fields at Complex Oxide-Semiconductor Interfaces

复杂氧化物-半导体界面的极化和电场的控制和操纵

• 批准号: 1006256
• 负责人: Charles Ahn
• 金额: $ 33.75万
• 依托单位: Yale University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-07-01 至 2013-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1006256&HistoricalAwards=false
• 关键词: Control; Manipulation; Polarization; Electric; Fields

Technical: The goal of the project is to control and manipulate polarization and electric fields at interfaces of crystalline oxides and semiconductor material. Key to achieving this goal is atomic level control of the microscopic form and structure of the interface, which requires advanced oxide molecular beam epitaxy (MBE) growth techniques. The research requires specialized characterization tools to probe buried epitaxial interfaces with the highest reciprocal space resolution, including high speed methods of measuring the crystal truncation rods of interface structures using synchrotron x-ray diffraction. Other physical and electrical structure characterization techniques include in-situ electrical transport measurements, in-situ surface diffraction and photoelectron spectroscopy, x-ray absorption spectroscopy, and transmission electron microscopy. The PIs combine these synthesis and characterization tools to develop new functional behavior in three specific areas: band offsets (interface dipoles), interface polarization, and single layer interface ferroelectrics. Each research direction is focused on a materials system suited to the relevant property under investigation: BaO for band offsets, SrTiO3 for interface polarization, and MX2-type layered films for ferroelectricity. The research addresses the fundamentals of how form (structure) affects function (electrical properties) at crystalline oxide-semiconductor interfaces. By considering crystalline oxides, one can apply a battery of atomic level control and structural characterization techniques to achieve a level of understanding of the microscopic structure that is not possible with amorphous oxides. Non-technical: The project addresses basic research issues in a topical area of materials science with high technological relevance. The research has the potential to transform the utility of semiconductor structures by engineering and tailoring the properties of crystalline oxide-semiconductor interfaces at the atomic layer level. A key component of the project involves undergraduate and post-baccalaureate STEM (science, technology, engineering, and mathematics) participation in the implementation and practice of these techniques. Undergraduates grow materials using oxide MBE in both classroom and research environments and characterize these materials using synchrotron scattering techniques. The STEM graduates are involved in the engineering development and improvement of the synthesis and characterization techniques. This project is aimed at enhancing the technical skills of STEM graduates whose career goals are to transition to permanent technical positions in industry.

技术：该项目的目标是控制和操纵晶体氧化物和半导体材料界面上的极化和电场。实现这一目标的关键是原子水平控制界面的微观形式和结构，这需要先进的氧化物分子束外延(MBE)生长技术。这项研究需要专门的表征工具来探测具有最高倒数空间分辨率的掩埋外延界面，包括使用同步加速器X射线衍射法测量界面结构的晶体截断棒的高速方法。其他物理和电子结构表征技术包括原位电传输测量、原位表面衍射和光电子能谱、X射线吸收光谱和透射电子显微镜。PI结合了这些合成和表征工具，在三个特定领域开发新的功能行为：带偏移(界面偶极子)、界面极化和单层界面铁电。每个研究方向都集中在与所研究的相关性质相适应的材料体系上：BaO用于带偏移，SrTiO_3用于界面极化，MX2型层状薄膜用于铁电。这项研究探讨了晶态氧化物-半导体界面的形态(结构)如何影响功能(电学性质)的基本原理。通过考虑晶态氧化物，人们可以应用原子水平控制和结构表征技术的电池，以达到对微观结构的理解水平，这是非晶态氧化物无法实现的。非技术性：该项目解决了材料科学中具有高度技术相关性的专题领域的基础研究问题。这项研究有可能通过在原子层水平上对晶体氧化物-半导体界面的性质进行工程设计和定制来改变半导体结构的用途。该项目的一个关键组成部分是本科生和毕业后的STEM(科学、技术、工程和数学)参与这些技术的实施和实践。本科生在课堂和研究环境中使用氧化物分子束外延生长材料，并使用同步辐射散射技术对这些材料进行表征。STEM毕业生参与合成和表征技术的工程开发和改进。该项目旨在提高STEM毕业生的技术技能，他们的职业目标是过渡到工业中的长期技术职位。