锗材料因其突出的空穴和电子迁移率，被认为是后22纳米技术代取代Si做MOSFET沟道材料的主要候选之一。然而长期以来Ge表面难于获得高质量的栅介质及低缺陷密度的界面是困扰其发展的核心问题。研究表明，这些难题有望通过复合高k介质和有效的界面调控获得解决。本项目拟选用镧系复合高k介质结合GeO2/Ge界面结构，在介质生长动力学、复合介质热力学稳定性计算、等离子体氧化动力学、GeO2/Ge界面反应等方面开展工作，围绕高k栅介质漏电流与其内部缺陷形成的物理关系以及GeO2/Ge界面反应微观机理两大科学问题进行研究。通过组分调整、结构设计、热力学计算等方法结合工艺优化，实现高质量、热稳定的高k介质；另一方面通过等离子体氧化、界面缺陷及微观结构表征、等方法结合热力学调控,实现低缺陷密度的界面。为Ge-MOS技术中所遇到的缺乏热稳定的栅介质、界面态密度过大、理论支撑不足等科学问题提供技术和理论解决方案。

Germanium is a promising candidate to replace silicon as the channel material of MOSFET in the post-22 nm node because of its high mobility. However, lacking of high-quality gate dielectric and defectless interface are important problems that hamper its development. Recent studies suggest that these problems may be solved by applying composite high-k dielectric and interfacial control. ..By focusing on the following two scientific issues, that are (i) the physical relationship between the high-k gate dielectric leakage current and the defects formation within the gate dielectric and (ii) GeO2/Ge interfacial reaction mechanism, we plan to employ lanthanum-based composite high-k dielectric together with GeO2/Ge interface structure to carry out this study through investigating the following aspects including dielectric growth kinetics, composite dielectric thermodynamic calculation, plasma oxidation kinetics, GeO2/Ge interfacial reaction and so on. On the one hand, we plan to realize the high-k dielectric for Ge with high quality and good thermal stability by changing its composition, designing its structure and thermodynamic calculation. On the other hand, in order to obtain an interface with low defects density, this project would applying plasma oxidation, interfacial defects characterization, structure characterization, and thermodynamic control. ..For Ge-MOS technology, several problems have to be overcome, such as no thermodynamically stable gate dielectric, very large interface state density, lacking of supporting theory. Towards these problems, the purpose of this project is to provide technical and theorectical solutions for them.