Defect evaluation in strain-relaxed Ge0.947Sn0.053 grown on (001) Si

Defects in Ge0.947Sn0.053 layers grown using molecular beam epitaxy on (001) Si substrates with 4.9% mismatch are investigated using optical, scanning, and transmission electron and atomic force microscopies. It is shown that the strain relaxation occurs via the introduction of 90° misfit dislocatio...

Ausführliche Beschreibung

Gespeichert in:
Bibliographische Detailangaben
Veröffentlicht in:Applied physics letters 2018-11, Vol.113 (19)
Hauptverfasser: Gupta, S., Shimura, Y., Richard, O., Douhard, B., Simoen, E., Bender, H., Nakatsuka, O., Zaima, S., Loo, R., Heyns, M.
Format: Artikel
Sprache:eng
Schlagworte:
Online-Zugang:Volltext
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
Beschreibung
Zusammenfassung:Defects in Ge0.947Sn0.053 layers grown using molecular beam epitaxy on (001) Si substrates with 4.9% mismatch are investigated using optical, scanning, and transmission electron and atomic force microscopies. It is shown that the strain relaxation occurs via the introduction of 90° misfit dislocations of short length, at the Ge0.947Sn0.053/Si interface. An irregular morphology in the form of mounds is observed on the surface of epitaxial Ge1−xSnx (0.031 ≤ x ≤ 0.093) and is found to be associated with carbon impurities at the hetero-interface. A low-cost and fast defect selective wet etching technique is described to determine the etch pit density in epitaxial Ge1−xSnx with a low Sn content (≤5.3%). On the basis of etch pit morphology, different defects, e.g., dislocations, stacking faults, and crystal originated particles, are distinguished.
ISSN:0003-6951
1077-3118
DOI:10.1063/1.5048683