Binding, Electronic Structure, and Growth of a Passive Interface: Ga203/GaAs(100)

该项目旨在从根本上了解GaAs上Ga 2 O3的基本形成和演变。摩托罗拉的合作者已经使用光致发光和电容-电压测量来表明Ga 2 O 3/GaAs（100）界面是未钉扎的，但界面的详细原子和电子结构是未知的。为了解除费米能级的钉扎，Ga 2 O 3与GaAs的结合必须足够强，使得干净的表面态被推入导带或价带，并且没有新的钉扎态形成。在这个项目中的方法是使用横截面和面内扫描隧道显微镜（STM）和光谱（STS），以确定化学键和电子结构的Ga 2 O 3/GaAs界面。 此外，将研究使用O、O2和O3氧化源的Ga 2 O3生长过程的化学。该项目解决了材料科学领域的基础研究问题，具有很高的潜在技术相关性。虽然硅的热氧化形成了一个很好的氧化物，以及一个电钝化的氧化物-半导体界面，但目前还没有在GaAs上形成栅极氧化物的商业工艺。 这种电介质非常重要，因为它可以支持基于GaAs的新MOS类技术，在电子学和光子学方面都具有优势。该研究将为电子/光子器件的新功能提供基础材料科学知识。在这些调查中将处理各种基本问题。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。 ***

This project aims for fundamental understanding of the basic formation and evolution of Ga2O3 on GaAs. Collaborators at Motorola have employed photoluminescence and capacitance-voltage measurements to show that the Ga2O3/GaAs(100) interface is unpinned, but the detailed atomic and electronic structure of the interface is unknown. In order to unpin the Fermi level, the binding of Ga2O3 to GaAs must be sufficiently strong that the clean surface states are pushed into either the conduction or the valence bands and no new pinning states are formed. The approach in this project is to use cross-sectional and in-plane scanning tunneling microscopy (STM) and spectroscopy (STS), to determine chemical bonding and electronic structure at the Ga2O3/GaAs interface. Additionally, the chemistry of the Ga2O3 growth process using O, O2 , and O3 oxidation sources will be investigated. %%%The project addresses basic research issues in a topical area of materials science having high potential technological relevance. While thermal oxidation of silicon forms an excellent oxidealong with an electrically passive oxide-semiconductor interface, there is no current commercialprocess to form gate oxides on GaAs. This dielectric is highly significant because it could underpin a new MOS-like technology based on GaAs with advantages in both electronics and photonics. The research will contribute basic materials science knowledge at a fundamental level to new capabilities in electronic/photonic devices. A variety of fundamental issues are to be addressed in these investigations. 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. ***