標題: | Atomic and electronic structures of thin NaCl films grown on a Ge(001) surface |
作者: | Tsay, Shiow-Fon Lin, D. -S. 物理研究所 Institute of Physics |
關鍵字: | Density functional calculations;Semiconductor-insulator interfaces;Alkali halides;Germanium;Surface structure;Thin film structures;Surface electronic phenomena |
公開日期: | 1-七月-2009 |
摘要: | Density functional theory (DFT) with LDA and GGA have been employed to study the interface and thin film properties of NaCl on a Ge(0 0 1) surface. The atomic and electronic structures of thin NaCl films from one to ten monolayers were analyzed. The layer adsorption energies show that a quasi-crystalline (0 0 1) fcc NaCl film is built up via a layer-by-layer growth mode with NaCl thickness above 2 ML. Simulated STM images show a well-resolved (1 x 1) NaCl atomic structure for sample bias voltage V(s) < -2.5 V and the bright protrusions should be assigned to the Cl(-) ions of the NaCl film. The Ge substrate dimer is reserved and buckled like a clean Ge(0 0 1)-p(2 x 2) surface as the result of weak interface interaction between the dangling bonds coming from valence pi states of the Ge substrate and the 3p states of the interfacial Cl(-) ion. These results are consistent with the experiments of STM, LEED and EELS. (C) 2009 Elsevier B.V. All rights reserved. |
URI: | http://dx.doi.org/10.1016/j.susc.2009.04.007 http://hdl.handle.net/11536/7004 |
ISSN: | 0039-6028 |
DOI: | 10.1016/j.susc.2009.04.007 |
期刊: | SURFACE SCIENCE |
Volume: | 603 |
Issue: | 13 |
起始頁: | 2102 |
結束頁: | 2107 |
顯示於類別: | 期刊論文 |