Interface Electronic Properties and Growth Parameters of Heterovalent Semiconductor Heterojunctions

9711851布里尔森该项目旨在促进对锌硒/砷化镓、砷化镓/锗硅和氮化镓/氧化铝界面和生长过程的了解，重点是界面能带对齐和深能级的控制。提出了一种优化异质结界面电学性质的综合方案，包括界面能带不连续性和抗缺陷形成和热降解的化学稳定性。分子束外延生长、掩埋界面的低能阴极发光和光致发光光谱、表面敏感的X射线和软X射线光电子能谱以及亚表面的光学陷阱光谱将被用来优化生长工艺，以改善电学性能和化学稳定性。它有望将界面的化学和电子特征与导致深能级和偶极形成的原子运动联系起来。对改变的覆盖层、衬底化学计量和外延中间层的使用进行光谱评估，以制定优化异质结界面特性的一般生长原则。%该项目致力于具有高度技术相关性的材料科学主题领域的基础研究问题。这项研究将在基础水平上为电子/光子器件的重要方面贡献基本的材料科学知识。此外，从研究中获得的基本知识和理解有望通过为设计和生产改进的材料和材料组合提供基本的理解和基础，从而有助于提高先进器件和电路的性能和稳定性。该计划的一个重要特点是通过在一个具有根本意义和技术意义的领域对学生进行培训，将研究和教育结合起来。***

9711851 Brillson This project seeks to advance understanding of ZnSe/GaAs, GaAs/GeSi, and GaN/Al2O3 interfaces and growth processes with emphasis on control of interface band alignment and deep levels. A comprehensive plan is presented for optimizing heterovalent heterojunction interface electronic properties, including both interfacial band discontinuities and chemical stability against defect formation and thermal degradation. The combination of molecular beam epitaxial growth, low energy cathodoluminescence and photoluminescence spectroscopies of buried interfaces, surface-sensitive x-ray and soft x-ray photoemission spectroscopies, and optical trap spectroscopies of subsurfaces will be employed to optimize growth processes for both improved electrical properties and chemical stability. It is expected to link interface chemical and electronic features with the atomic movements leading to deep level and dipole formation. Use of altered overlayer, substrate stoichiometries, and epitaxial interlayers will be assessed spectroscopically to develop general growth principles for optimizing heterojunction interface properties. %%% The project addresses basic research issues in a topical area of materials science having high technological relevance. The research will contribute basic materials science knowledge at a fundamental level to important aspects of electronic/photonic devices. Additionally, the fundamental knowledge and understanding gained from the research is expected to contribute to improving the performance and stability of advanced devices and circuits by providing a fundamental understanding and a basis for designing and producing improved materials, and materials combinations. 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. ***