Formation of heterovalent interfaces: A combined photoemission and ab initio DFT study of GaP/Si heterostructures

异价界面的形成：GaP/Si 异质结构的光电发射和从头算 DFT 组合研究

基本信息

批准号：
391502515
负责人：
Professor Dr. Thomas Hannappel
金额：
--
依托单位：
Fyzikální ústav AV ČR
依托单位国家：
德国
项目类别：
Research Grants
财政年份：
2018
资助国家：
德国
起止时间：
2017-12-31 至 2021-12-31
项目状态：
已结题

来源：
https://gepris.dfg.de/gepris/projekt/391502515?language=en
关键词：
Formation heterovalent interfaces combined photoemission

项目摘要

Integration of III-V semiconductors on silicon is desirable for a new generation of microelectronic power devices, high-efficiency multi-junction solar cells and photolytic tandem absorbers for the renewable generation of hydrogen. GaP/Si(001) is the ideal candidate for a pseudomorphic virtual substrate, a generic element for high-efficiency optoelectronic device structures. The goal is to overcome the today limiting challenges, which are related to polar-on-nonpolar heteroepitaxy, prior further III-V integration in order to grow low-defect active material. The preparation of sharp GaP/Si(001) interfaces thereby is the critical technological step in metalorganic chemical vapor deposition (MOCVD), because it strongly impacts the quality of subsequently grown epitaxial films and the final device performance. Preliminary work showed that the additional group-V element arsenic plays a decisive role for tuning the interfacial structure. Today, interface formation mechanisms are not well understood at the atomic scale and the electronic structure of these buried interfaces has not yet been resolved. Recently, there has been much progress to reduce defect formation considerably at buried GaP/Si(001) heterointerfaces. Therefore, this interface is not only significant as generic element for optoelectronic application, but also as model structure, which is the key to enable comparative experimental and ab initio studies of the interface electronic structure. In this bilateral project, we will join our complementary expertise in industrially scalable, state-of-the-art epitaxial growth by MOCVD, in advanced interface analysis and in ab initio theory to provide all essential elements for a comprehensive heterointerface study. Thereby, we aim to resolve a historic open question in polar-on-nonpolar heteroepitaxy: How can interfaces form as sharp as possible, while compensating interface charges in order to get well-defined electronic properties across the interface? We will apply a unique methodology combining preparation, optical in situ spectroscopy, lab-based as well as synchrotron-based photoelectron spectroscopy techniques, depth profiling and ab initio density functional theory calculations in order to establish a conclusive atomic-scale understanding of the structural and electronic properties of GaP/Si(001) and GaP/Si(001):As heterointerfaces. The structure of the interface will be studied both with bottom-up, top-down and in situ approaches. We will introduce dedicated modifications of the atomic structure in order to understand how the electronic properties of the heterointerface can be tuned and how this can be controlled in situ. The objective of this project is to gain a fundamental understanding of III-V/IV heterointerface formation on the atomic scale with direct implications for high-performance device applications.

对于新一代的微电子功率设备，高效效率的多开关太阳能电池和光解串联吸收剂，对于可再生生成的氢而言，III-V半导体在硅上的整合是可取的。 gap/si（001）是伪型虚拟底物的理想候选者，这是高效光电设备结构的通用元素。目的是克服与当今的限制挑战，这些挑战与非极性杂音杂质的相关，此前是III-V的进一步集成，以增强低缺陷的活性材料。因此，尖锐的间隙/Si（001）界面的制备是金属有机化学蒸气沉积（MOCVD）的关键技术步骤，因为它强烈影响随后成长的外延膜和最终设备性能的质量。初步工作表明，附加的组V元素砷在调整界面结构时起着决定性的作用。如今，界面形成机制在原子量表上尚未得到充分了解，并且尚未解决这些埋入界面的电子结构。最近，在埋入的GAP/SI（001）异质方面大大减少了缺陷形成。因此，该界面不仅是光电应用的通用元素，而且是模型结构，这是启用界面电子结构的比较实验和AB启动研究的关键。在这个双边项目中，我们将加入MOCVD，高级界面分析和从头算理论中的可扩展性，最先进的外观增长的互补专业知识，为全面的异性界面研究提供了所有基本要素。因此，我们旨在解决一个历史性的开放问题，以极地非极性杂质结构：如何尽可能清晰地形成接口，同时补偿界面电荷以在界面上获得明确的电子特性？我们将采用一种独特的方法，结合制备，光学原位光谱，基于实验室以及基于同步加速器的光电子光谱技术，挖掘和启动密度的功能理论计算，以建立对gap/si（001）和gap/si的结构和电源的结论性原子级的理解。界面的结构将通过自下而上，自上而下和原位方法研究。我们将介绍原子结构的专用修改，以了解如何调整异源面的电子特性以及如何原位控制它。该项目的目的是在原子量表上获得对III-V/IV杂界形成的基本理解，对高性能设备应用的影响直接影响。