Structural and optical characterization of self-assembled Ge nanocrystal layers grown by plasma-enhanced chemical vapor deposition
2014 (English)In: Nanotechnology, ISSN 0957-4484, E-ISSN 1361-6528, Vol. 25, no 40, 405705- p.Article in journal (Refereed) Published
We present a structural and optical study of solid-state dispersions of Ge nanocrystals prepared by plasma-enhanced chemical vapor deposition. Structural analysis shows the presence of nanocrystalline germanium inclusions embedded in an amorphous matrix of Si-rich SiO2. Optical characterization reveals two prominent emission bands centered around 2.6 eV and 3.4 eV, and tunable by excitation energy. In addition, the lower energy band shows an excitation power-dependent blue shift of up to 0.3 eV. Decay dynamics of the observed emission contains fast (nanosecond) and slow (microseconds) components, indicating contributions of several relaxation channels. Based on these material characteristics, a possible microscopic origin of the individual emission bands is discussed.
Place, publisher, year, edition, pages
2014. Vol. 25, no 40, 405705- p.
germanium, nanocrystals, self-assembly, optical properties
IdentifiersURN: urn:nbn:se:kth:diva-155143DOI: 10.1088/0957-4484/25/40/405705ISI: 000342503800011ScopusID: 2-s2.0-84907186612OAI: oai:DiVA.org:kth-155143DiVA: diva2:761033
QC 201411052014-11-052014-10-312014-11-05Bibliographically approved