AN ATOMIC VIEW OF SURFACE SELF-DIFFUSION: TUNGSTEN ON TUNGSTEN,

Abstract

Surface diffusion of tungsten adatoms on several smooth, low index planes of the tungsten lattice has for the first time been followed by direct observation of individual atoms in the ion microscope. Contrary to expectation, the mobility at room temperature is found to increase in the order (211) > (321) approx. = (110) > (310) approx. = (111). Migrating atoms are reflected at the boundaries of the (110), (211), and (321) planes; on the latter two, motion along atomic rows is favored over diffusion across lattice steps. From quantitative determinations of the rate of change of the mean square displacement, diffusion coefficients were obtained. Differences in diffusion on the (211) and (321)--planes of very similar structure--suggest a weakening of interatomic forces at lattice edges. (Author)

Document Details

Document Type
Technical Report
Publication Date
Oct 01, 1965
Accession Number
AD0627837

Entities

People

  • F. G. Hudda
  • Gert Ehrlich

Organizations

  • General Electric

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Boundaries
  • Coefficients
  • Diffusion
  • Diffusion Coefficient
  • Displacement
  • Microscopes
  • Mobility
  • Observation
  • Tungsten

Readers

  • Fluid Dynamics.
  • Quantum spin resonance or Electron Paramagnetic Resonance spectroscopy.
  • Thin Film Deposition Science.