Si(111) strained layers on Ge(111): Evidence for c ( 2 × 4 ) domains

The tensile-strained Si(111) layers grown on top of Ge(111) substrates are studied by combining scanning tunneling microscopy, low-energy electron diffraction, and first-principles calculations. It is shown that the layers exhibit c(2×4) domains, which are separated by domain walls along 1¯10 direct...

Full description

Saved in:
Bibliographic Details
Published in:Physical review. B 2017-08, Vol.96 (8), Article 085401
Main Authors: Zhachuk, R., Coutinho, J., Dolbak, A., Cherepanov, V., Voigtländer, B.
Format: Article
Language:English
Subjects:
Adatoms
Chemical bonds
Compressive properties
Dimers
Domain walls
First principles
Free energy
Germanium
Heat of formation
Low energy electron diffraction
Silicon
Stacking faults
Substrates
Surface energy
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The tensile-strained Si(111) layers grown on top of Ge(111) substrates are studied by combining scanning tunneling microscopy, low-energy electron diffraction, and first-principles calculations. It is shown that the layers exhibit c(2×4) domains, which are separated by domain walls along 1¯10 directions. A model structure for the c(2×4) domains is proposed, which shows low formation energy and good agreement with the experimental data. The results of our calculations suggest that Ge atoms are likely to replace Si atoms with dangling bonds on the surface (rest-atoms and adatoms), thus significantly lowering the surface energy and inducing the formation of domain walls. The experiments and calculations demonstrate that when surface strain changes from compressive to tensile, the (111) reconstruction converts from dimer-adatom-stacking fault-based to adatom-based structures.
ISSN:2469-9950
2469-9969
DOI:10.1103/PhysRevB.96.085401