AVS 49th International Symposium
    Surface Science Thursday Sessions
       Session SS+EL-ThM

Paper SS+EL-ThM7
Absolute Orientation-Dependent TiN(001) Step Energies from Two-Dimensional Equilibrium Island Shape and Coarsening Measurements on Epitaxial TiN(001) Layers

Thursday, November 7, 2002, 10:20 am, Room C-110

Session: Structure of Semiconductor Surfaces & Interfaces
Presenter: S. Kodambaka, University of Illinois
Authors: S. Kodambaka, University of Illinois
S.V. Khare, University of Illinois
V. Petrova, University of Illinois
A. Vailionis, Stanford University
I. Petrov, University of Illinois
J.E. Greene, University of Illinois
Correspondent: Click to Email
In situ high-temperature (1030-1185 K) scanning tunneling microscopy was used to determine the equilibrium shapes of two-dimensional TiN vacancy islands on atomically-smooth terraces of epitaxial TiN(001) layers. Inverse Legendre transformations of the equilibrium island shapes yield relative step energies as a function of step orientation within an orientation-independent scale factor @lambda@, the equilibrium chemical potential of the island per unit TiN molecular area. We then use quantitative TiN(001) adatom island coarsening measurements to determine @lambda@ and, hence, absolute orientation-dependent step energies @beta@ and step stiffnesses @td beta@. For <110> and <100> steps on TiN(001), we obtain: @beta@@sub 110@ = 0.21±0.05 eV/Å, @beta@@sub 100@ = 0.25±0.05 eV/Å, @td beta@@sub 110@ = 0.9±0.2 eV/Å, and @td beta@@sub 100@ = 0.07±0.02 eV/Å. From the @td beta@ values, we calculate kink formation energies @epsilon@@sub 110@ = 0.40±0.2 eV and @epsilon@@sub 100@ = 0.11±0.1 eV based on the unrestricted terrace-step-kink model.