β-Sn与4H-SiC界面性质的第一性原理计算

The first principles calculation of the interfacial properties of β-Sn and 4H-SiC

为研究金属钎料与SiC陶瓷的界面结合方式,采用基于密度泛函理论的第一性原理方法,对Sn(001)/4H-SiC(0001)界面进行几何优化,得到优化后界面体系的结构,从分离功表征结合强度以及电子结构布居分析的角度解释界面结合本质和键合方式。结果表明:SiC陶瓷中C封端界面的分离功高于Si封端界面的分离功,Sn原子与C原子间形成的离子共价键在界面结合的成键中占有主要的地位。

In order to study the interface between filler metal and SiC ceramics, based on the first-principles method of density functional theory, the Sn (001)/4H-SiC(0001) interface is geometrically optimized to obtain the structure of the optimized interface system. The interface bonding nature and bonding mode are explained from the perspective of the binding strength of the separation work and the population analysis of the electronic structure. The results show that the separation work of the C-terminated interface in SiC ceramics is higher than the separation work at the Si-terminated interface. The ionic covalent bond formed between the Sn atom and the C atom plays a major role in the bonding of the interface.