Structural analysis of the c(4 × 2) reconstruction in Si(0 0 1) and Ge(0 0 1) surfaces by low-energy electron diffraction
- 作者：Tetsuroh Shirasawa ; Seigi Mizuno and Hiroshi Tochihara
- 关键词：Si(0 0 1) ; Ge(0 0 1) ; Low-energy electron diffraction (LEED) ; Surface structure ; Morphology ; Roughness ; Topology
- 刊名：Surface Science
- 出版年：2006
- 期刊代码：104_00396028
- 类别：ch
- 出版时间：15 February 2006
- 卷：600
- 期：4
- 页码：815-819
- 文件大小：277 K
摘要
The c(4 × 2) structures in (0 0 1) surfaces of Si and Ge have been studied by low-energy electron diffraction (LEED). Using a proper cleaning method for the Si surface, we were able to observe clear c(4 × 2) LEED patterns up to incident energy of 400 eV as well as the Ge surface. Extensive experimental intensity–voltage curves allowed us to optimize the asymmetric dimer model up to the eighth layer (including the dimer layer) in depth in the dynamical LEED calculation. Optimized structural parameters are almost the same for the Si and Ge except for the height of the buckled-up atom of the asymmetric dimer. For the Ge surface, the structural parameters are in excellent agreement with those obtained by a previous theoretical calculation. The tilt angle and bond length of the dimer are 18 ± 1 (19 ± 1)° and 2.4 ± 0.1 (2.5 ± 0.1) for the Si(0 0 1) (Ge(0 0 1)), respectively.