中国物理B ›› 2008, Vol. 17 ›› Issue (12): 4580-4584.doi: 10.1088/1674-1056/17/12/041

• CONDENSED MATTER: STRUCTURAL, MECHANICAL, AND THERMAL PROPERTIES • 上一篇    下一篇

Structural transformation of Ge dimmers on Ge(001) surfaces induced by bias voltage

秦志辉, 时东霞, 高鸿钧   

  1. Nanoscale Physics & devices Laboratory, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
  • 收稿日期:2008-03-20 修回日期:2008-04-28 出版日期:2008-12-20 发布日期:2008-12-20
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant Nos 90406022, 10674159 and 60771037) and the National Basic Research Program of China (Grant No 2006CB921305).

Structural transformation of Ge dimmers on Ge(001) surfaces induced by bias voltage

Qin Zhi-Hui (秦志辉), Shi Dong-Xia (时东霞), Gao Hong-Jun (高鸿钧)   

  1. Nanoscale Physics & devices Laboratory, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
  • Received:2008-03-20 Revised:2008-04-28 Online:2008-12-20 Published:2008-12-20
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant Nos 90406022, 10674159 and 60771037) and the National Basic Research Program of China (Grant No 2006CB921305).

摘要: Scanning tunneling microscopy is utilized to investigate the local-bias- voltage-dependent transformation between (2x1) and c(4x2) structures on Ge(001) surfaces, which is reversibly observed at room temperature and a critical bias voltage of -0.80V. Similar transformation is also found on an epitaxial Ge islands but at a slightly different critical bias voltage of -1.00V. It is found that the interaction between the topmost atoms on the STM tip and the atoms of the dimers, and the pinning effect induced by Sb atoms, the vacancies or the epitaxial clusters, can drive the structural transformation at the critical bias voltage.

Abstract: Scanning tunneling microscopy is utilized to investigate the local-bias- voltage-dependent transformation between (2x1) and c(4x2) structures on Ge(001) surfaces, which is reversibly observed at room temperature and a critical bias voltage of -0.80V. Similar transformation is also found on an epitaxial Ge islands but at a slightly different critical bias voltage of -1.00V. It is found that the interaction between the topmost atoms on the STM tip and the atoms of the dimers, and the pinning effect induced by Sb atoms, the vacancies or the epitaxial clusters, can drive the structural transformation at the critical bias voltage.

Key words: scanning tunneling microscopy, surface structures, Ge, structural transition

中图分类号:  (Phase transitions and critical phenomena)

  • 68.35.Rh
61.72.J- (Point defects and defect clusters) 68.35.B- (Structure of clean surfaces (and surface reconstruction)) 68.37.Ef (Scanning tunneling microscopy (including chemistry induced with STM)) 68.55.-a (Thin film structure and morphology)