叠层结构对新型MOS场效应晶体管的界面调控和性能优化研究

The limit of the theory and technology of traditional silicon devices promotes breakthroughs and innovation of the new high k gate dielectric materials and processes. In the silicon field effect transistor, the introduction of high-k gate dielectric could cause degradation of the channel carrier mobility, which may reduce the device performance. A high carrier mobility of the material as a new channel material, a rare earth element and N doped Hf-based high-k films as gate dielectric, and the interfacial layer be introduced between the channel layer and the gate dielectric materials are expected to build new field effect transistors with high carrier mobility. The project intends to take atomic layer deposition technique to in situ prepare high-k gate dielectric/interface stacks and build a new channel MOSFET structure. Study the effect of the interfacial layer and high-k gate dielectric film on the interfacial properties, optical properties, band offsets and electrical properties of the gate stack structure; thus reveal the influence of parameters of gate stacks on the carrier mobility; and find out the best preparation process route with high carrier mobility, more stable interface performance, fewer defects and appropriate band offsets. Propose the methods of optimization the performance of gate stacks. The work would provide experiment foundation and scientific basis for clarification interaction mechanism of the new channel materials and gate stacks and design the next generation new channel field effect transistor.

传统硅器件理论与技术的双重极限推动着新型高k栅极材料与工艺的突破与创新。而在硅基场效应管中引入高k栅介质会导致沟道载流子迁移率下降，降低器件性能。以高载流子迁移率基体为沟道材料，以稀土元素及N掺杂Hf基高k薄膜为栅介质，通过在沟道和栅介质间引入界面钝化层有望构筑高载流子迁移率新型场效应晶体管。本项目拟采取原子层沉积原位生长技术在新型基体材料上制备高k栅介质/界面层叠层结构，并构筑新型叠层结构场效应晶体管。研究不同界面层及高k栅介质层对栅叠层结构的界面特性、光学性质、能带偏移及电学性能的影响，获取最优化性能参数，建立叠层结构参数变化对载流子迁移率的影响规律,找出界面性能稳定、缺陷少、能带偏移合适及载流子迁移率高的新型沟道栅介质材料最佳制备工艺路线，提出优化栅叠层结构性能的方法。本项目的开展将为新型沟道材料与栅叠层结构相互作用机理的澄清及下一代新型场效应晶体管的设计提供实验基础和科学依据。

高k栅介质材料、界面层及沟道材料都是影响未来场效应晶体管性能的重要因素。本项目开展了不同界面层、不同高k栅介质层及高载流子迁移率沟道材料对栅叠层结构的界面特性、光学性质、能带偏移及电学性能的影响，获取了最优化性能参数，建立了叠层结构参数变化对载流子迁移率的影响规律，找出了界面性能稳定、缺陷少、能带偏移合适及载流子迁移率高的新型沟道栅介质材料最佳制备工艺路线，并提出优化栅叠层结构性能的方法。本项目的成功实施，为新型沟道材料与栅叠层结构相互作用机理的澄清及下一代新型场效应晶体管的设计提供实验基础和科学依据。