高k栅介质/钝化层/InGaAs叠层结构设计、界面失稳调控及性能优化

High-k/interface passivatio layer/InGaAs is the best gate stack which satisfies the demand of design in the field of high temperature communication. Such international research has just started and belongs to the frontier of current MOSFET. This project intends to start from the new device structures and new materials integration perspective and oriented by suppressing the heterointerface instability and performance optimization of MOSFET. Through the design of the gate stack, investigating on the correlation between order degree of heterointerface and process parameters, achieving the repair of interface defect states, and gaining the non fermi level pinning MOS heterointerface will be carried out. Studying the effect of rare earth and N co doping on the heterointerface and revealing the origin of heterointerface instability and performance loss of optimization will be studied. Optimized interface structure and the optimum process parameter which suppress the heterointerface instability will be determined. Suppression of oxygen vacancy and improvement in effectiveness of the order degree by co-doping will be explored. Basic problems, such as the density of interface state, the carrier mobility, and scattering mechanism will be investigated. We will solve the degradation of carrier mobility induced by gate dielectric deposition, achieve new high-k dielectrics and gate stacks with thermodynamical stability and Fermi level unpinning, and succeed in fabricating InGaAs-MOSFET prototype device. Breakthrough of this project will provide experimental foundation and theoretical basic for the device design of next generation which works in extreme environment and owns important scientific significance and practical value.

高k栅/钝化层/InGaAs是满足当前高温通讯领域MOSFET设计需求的最佳叠层结构，国际研究刚刚起步，属于当前MOSFET研究领域的前沿。本项目以抑制异质界面失稳和MOSFET性能优化为导向，通过引入钝化层优化沟道与高k栅的界面特性，研究界面有序度和工艺参数的相关性，实现对界面缺陷态的修复，获取无费米能级钉扎的异质界面；研究稀土和N共掺对异质界面的影响规律，揭示异质界面失稳和性能失优的起源，确定优化界面结构、抑制界面失稳的最佳工艺条件，探索共掺杂抑制氧空位，提高薄膜有序度的有效性；研究界面态密度、载流子迁移率及散射机制等基础问题，解决由栅介质沉积诱导的载流子迁移率退化这一难题，获取热力学稳定、无费米能级钉扎的新型高k栅与叠层结构，构筑InGaAs-MOSFET原型器件。本课题的突破, 将为满足下一代工作于极端环境的新型器件的设计提供实验基础和理论依据，有重要的科学意义和实用价值。

传统硅器件理论与技术的双重极限推动着新型高k栅材料与工艺的突破与创新，而硅基晶体管中高k栅介质的引入导致了沟道载流子迁移率下降，器件性能恶化。本项目以抑制异质界面失稳和MOSFET性能优化为导向，通过引入钝化层优化沟道与高k栅的界面特性，研究界面有序度和工艺参数的相关性，实现对界面缺陷态的修复，获取了无费米能级钉扎的异质界面；研究稀土和N共掺对异质界面的影响规律，揭示异质界面失稳和性能失优的起源，确定优化界面结构、抑制界面失稳的最佳工艺条件，探索共掺杂抑制氧空位，提高薄膜有序度的有效性；研究界面态密度、载流子迁移率及散射机制等基础问题，解决由栅介质沉积诱导的载流子迁移率退化这一难题，获取热力学稳定、无费米能级钉扎的新型高k栅与叠层结构。围绕基金研究计划目标，在过去四年中，项目组成员系统开展了不同本征态高k栅介质的制备、物性表征、界面的调控及MOS器件的性能优化；通过沉积自清洁效应的钝化层获取了准共格的界面，发展了高载流子迁移率沟道基体上稀土元素掺杂的Hf基薄膜制备技成术，找出了满足未来栅介质材料要求的叠层材料；通过引入界面钝化技术，成功实现了热力学稳定，无费米能级钉扎的新型高k材料与叠层栅结构，构筑了高载流子迁移率沟道衬底上叠层结构原型器件，确定了具有最优化性能的HfRON/IL/沟道叠层结构制备技术路线，为高性能、快速新型MOSFET应用提供理论和实验依据。 在本项目的资助下，共发表41篇国际期刊论文，其中通讯作者论文41篇。本课题的突破, 将为满足下一代工作于极端环境的新型器件的设计提供实验基础和理论依据，有重要的科学意义和实用价值。