应用于硅基MOSFET高k介质种子层和沟道隔离层双重角色的氟化石墨烯探索研究

本项目针对目前制约硅基MOS器件发展的难点之一- - -高k介质层的界面改良问题进行研究，提出采用新型二维绝缘材料氟化石墨烯，作为ALD 高k 介质生长种子层和沟道隔离层双重角色，探索其在硅基MOS器件中的应用前景。氟化石墨烯因其六圆环状致密结构、高韧性共价键绝缘态、无悬挂键原子层平整界面等特性，能有效阻挡介质与硅界面间原子相互扩散，阻止界面硅化物和过渡硅酸盐层副产物的生成，有助于形成高质量的介质/硅沟道界面。在ALD生长和后续退火过程中，氟化石墨烯因层间作用主要为范德华力，能有效释放界面间的失配应力和减少陷阱界面态生成，为获得低声子散射、薄过渡层的高k介质/硅沟道高质量界面提供了新的途径。本项目将结合量子输运与DFT数值模拟，系统性实验研究氟化石墨烯有效隔离高k介质/硅沟道界面的物理机制与隔离效果，分析引入氟化石墨烯应用于硅基MOS器件的优缺点，为其未来应用探索提供理论预测和关键技术指导。

Interface and mid-gap trapping states of high-k dielectrics play a crucial role in high-performance MOSFETs. In this proposal, by combining with theoretical study and DFT simulation, we will experimentally explore the feasibility of fluorinated graphene as ALD seed-layer on Si substrate for high-k dielectric growth. Fluorinated graphene provides an atomically smooth and sharp interface for high-k/Si substrates, which can induce lower interface defect density, thinner interfacial transition layer, and better surface passivation for high-k dielectrics. The advantages and limitations of fluorinated graphene as the ALD seed-layer will also be discussed. Our systematic work might promote the high performance and reliability of Si-MOSFETs with thinner high-k EOTs.