AVS 45th International Symposium
    Surface Science Division Thursday Sessions
       Session SS-ThP

Paper SS-ThP7
Step Fluctuations on Vicinal Si(113)

Thursday, November 5, 1998, 5:30 pm, Room Hall A

Session: Surface Science Division Poster Session
Presenter: K. Sudoh, Osaka University, Japan
Authors: K. Sudoh, Osaka University, Japan
T. Yoshinobu, Osaka University, Japan
H. Iwasaki, Osaka University, Japan
E.D. Williams, University of Maryland
Correspondent: Click to Email
The properties of steps play an important role in the description of dynamics of processes such as faceting and crystal growth. The vicinal surfaces of Si(113) are a model system for studying the evolution of steps into stable facets involving step-step attractions.@footnote 1@ In this paper, we investigate quantitatively the fluctuation properties of steps relevant to step coalescence using scanning tunneling microscopy (STM) on a Si(113) surface miscut along a low symmetry azimuth. In local thermal equilibrium at 710 °C, which is near the faceting transition temperature, coexistence of single, double, triple, and quadruple steps has been observed. To determine the dependence of the step stiffness on step height, we have measured the step-correlation function@footnote 2@ for the steps with different heights from STM images. This result shows that the step stiffness is proportional to the step height. This behavior can be qualitatively understood in terms of a terrace-step-kink (TSK) model which includes a short range step-step attraction. Performing Monte Carlo calculations, we have found that the linear dependence of the step stiffness on step height is expected only near the faceting temperature where unbinding of steps becomes facile. The high resolution STM images of the edge of triple and quadruple-steps evidently reveal significant unbinding of steps, in agreement with the prediction. @FootnoteText@ @footnote 1@S. Song and S. G. J. Mochrie, Phys. Rev. B51, 10068 (1995) @footnote 2@N. C. Bartelt, T. L. Einstein, and E. D. Williams, Surf. Sci. 273, 308 (1992)