New Methods for Treatment of Electron Correlation and Surface Dynamics (FY91 AASERT)
Abstract
The SiGe results were discussed in detail in the last AASERT report, so we eschew them here. The F2 reactive scattering on Si(100) was the first study in a series to ascertain the kinetics of surface processes, including etching of silicon. We calculated reaction probabilities for F2 impinging on silicon, as a function of translational and vibrational energy in the F2 molecules. We find that translational excitation is slightly more effective than vibrational excitation at increasing the reactivity of F2, but that vibrational excitation is most effective for producing precursors leading to etching (SiF2). We find that F-atom abstraction, where one Si-F bond is formed while the other F atom in the F2 molecule leaves the surface, is a very probable reaction due to the enormous exothermicity of the reaction (-100 kcal/mol exothermic do deposit only one F on the silicon surface and -200 kcal/mol to deposit both F atoms). These scattered F atoms do not have time to equilibrate with the surface, as is illustrated by the fact that they are translationally hot and do not come off in a cosine distribution. We have also recently studied the reaction of F2 molecules with stepped and defective Si(100) surfaces.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 30, 1994
- Accession Number
- ADA285177
Entities
People
- Emily A. Carter
Organizations
- University of California, Los Angeles