Abstract
We have studied the self-diffusion of W single adatoms on the W(110), W(211) and W(321) surfaces, using a modified fourth moment approximation to tight-binding theory. The binding sites of adatoms on those surfaces are determined and they are in good agreement with experimental observations. The activation energy and pre-exponential factor of single W adatom diffusion on these surfaces have been calculated, and they are in reasonable agreement with FIM (field ion microscopy) results. The exchange mechanism is also investigated for all surfaces and it is found to be unfavorable on the (110) and (211) surfaces. For the (321) surface, the exchange mechanism is unfavorable for adatom diffusion from a most stable site, but the activation energy is much smaller for an adatom on the meta-stable site replacing a channel atom.
Original language | English (US) |
---|---|
Pages (from-to) | 58-67 |
Number of pages | 10 |
Journal | Surface Science |
Volume | 319 |
Issue number | 1-2 |
DOIs | |
State | Published - Nov 1 1994 |
Externally published | Yes |
ASJC Scopus subject areas
- Condensed Matter Physics
- Surfaces and Interfaces
- Surfaces, Coatings and Films
- Materials Chemistry