Simultaneous layer-by-layer and step-flow sublimation on the CdTe(001) surface derived from a diffraction analysis

Citation
H. Neureiter et al., Simultaneous layer-by-layer and step-flow sublimation on the CdTe(001) surface derived from a diffraction analysis, PHYS REV B, 61(8), 2000, pp. 5408-5415
Citations number
42
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
PHYSICAL REVIEW B
ISSN journal
1098-0121 → ACNP
Volume
61
Issue
8
Year of publication
2000
Pages
5408 - 5415
Database
ISI
SICI code
1098-0121(20000215)61:8<5408:SLASSO>2.0.ZU;2-Q
Abstract
High-resolution low-energy electron diffraction (HRLEED), mass spectrometry , and computer simulations using a solid-on-solid model were combined to st udy the sublimation kinetics of the CdTe(001) surface. The HRLEED spot prof ile measurements show that specular spot intensity oscillations during subl imation are caused by an only small variation (similar to 15%) of the step density, and that the step flow contribution dominates the sublimation proc ess. Consequently, two different activation energies were derived from the mass desorption (1.55 eV) and the oscillation frequency of the HRLEED inten sity (1.94 eV). These findings are confirmed by computer simulations of the sublimation on irregularly stepped surfaces. These show a mixed sublimatio n mode with vacancy nucleation (leading to intensity oscillations) only on the largest terraces and step flow otherwise. On the basis of these results , we can explain discrepancies in earlier determined sublimation energies.