Details

Autor(en) / Beteiligte

• WEDLER, G
• SCHNEIDER, C. M
• TRAMPERT, A
• KOCH, R

Titel

Strain relief of heteroepitaxial bcc-Fe(001) films

Ist Teil von

• Physical review letters, 2004-12, Vol.93 (23), p.236101.1-236101.4, Article 236101

Ort / Verlag

Ridge, NY: American Physical Society

Erscheinungsjahr

2004

Quelle

American Physical Society

Beschreibungen/Notizen

• The strain relief of heteroepitaxial bcc-Fe(001) films, deposited at 520-570 K onto MgO(001), has been investigated by scanning tunneling microscopy. In accordance with real-time stress measurements, the tensile misfit strain is relieved during coalescence of flat, mainly 2-3 monolayers (ML) high Fe islands at the high thickness of approximately 20 ML. To accommodate the misfit between merging strain-relaxed islands, a network of 1/2[111] screw dislocations is formed. A strong barrier for dislocation glide--which is typical for bcc metals--is most likely responsible for the big delay in strain relief of Fe/MgO(001), since only the elastic energy of the uppermost layer(s) is available for the formation of an energy-costly intermediate layer.