中文摘要：

采用基于密度泛函理论框架下的第一性原理,研究石墨烯与Ge衬底之间的界面结构.计算结果表明,在3种衬底Ge（111）、Ge（100）和Ge（110）上界面结合能有相同的规律,均在平衡距离为3.3A时获得最低能量,平均每个碳原子的界面结合能分别为24.3 meV、21.1 meV和23.3 meV;通过构造0～60°之间不同的界面夹角,发现一个高对称性的界面结构;相比本征Ge衬底,石墨烯与H钝化后Ge衬底之间的界面平衡距离增大,结合能降低;H钝化能有效地屏蔽石墨烯与Ge衬底之间的相互作用,恢复了本征石墨烯的电子性质,起到缓冲层作用.

英文摘要：

According to the DFT-based first-principles, the interface structure between graphene and Ge sub- strate was studied. The same trends were demonstrated by interface binding energy between graphene and three sub- strate （Ge（11l）, Ge（100） and Ge（110））. All of the above structures got the equilibrium distance at 3.3 A, and the interface binding energy was 24. 3 meV for Ge（111）, 21. 1 meV for Ge（100） and 23. 3 meV for Ge（110）. A high symmetry interface structure was found by studying a serial of interface angles from 0° to 60°. The equilibrium dis- tance between graphene and H-passivated Ge substrate was increased while its interface binding energy was decreased, compared with clean Ge substrate. The interaction between graphene and Ge substrate could be effectively shielded by H atoms passivation buffer layer, recovering the electronic property of pristine graphene.