Step Fluctuations on Vicinal Si(113)

Abstract
The fluctuation properties of steps relevant to step coalescence have been measured using scanning tunneling microscopy on a Si(113) surface miscut along a low symmetry azimuth. In local thermal equilibrium at 710°C, coexistence of single, double, triple, and quadruple steps has been observed. From direct measurement of the step-correlation function, the step stiffness is shown to be proportional to the step height, with an additional stabilization of double-height steps. This result is shown to require a step-step attraction energy close to kT.