AVS 45th International Symposium
    Surface Science Division Wednesday Sessions
       Session SS3-WeM

Paper SS3-WeM10
Evidence and a Model for a Chemically Mediated Roughness Transition

Wednesday, November 4, 1998, 11:20 am, Room 314/315

Session: Surface Dynamics and Roughening
Presenter: E.A. Irene, University of North Carolina, Chapel Hill
Authors: E.A. Irene, University of North Carolina, Chapel Hill
C. Zhao, University of North Carolina, Chapel Hill
Q. Liu, University of North Carolina, Chapel Hill
Correspondent: Click to Email
In our previous research we have followed the changes effected by oxidation on purposely roughened and initially smooth Si surfaces via atomic force microscopy (AFM) and spectroscopic ellipsometry (SE) and a new technique called spectroscopic immersion ellipsometry (SIE).@footnote 1,2@ For initially rough surfaces both thermal and plasma oxidation yield smoother surfaces and this can be understood from the changes in the local free energy at asperities, viz. the Kelvin equation. What was surprising was that initially smooth Si surfaces roughen upon oxidation. These results are not contradictory, since the roughness magnitudes do not cross, but these results strongly suggest a limiting roughness. Furthermore, a chemically mediated roughening transition explains the observations although this mechanism is not yet proven. The experimental and modeling results will be presented. @FootnoteText@ @footnote 1@Q. Liu, L. Spanos, C. Zhao and E.A. Irene, J. Vac. Sci. Technol. A, 13, 1977 (1995). @footnote 2@C. Zhao, Y.Z. Hu, T. Labayen, L. Lai and E.A. Irene, J. Vac. Sci. Technol. A, 16, 57, (1998).