Fabrication of ZnO quantum dots embedded in an amorphous oxide layer

Kyoung-Kook Kim; Koguchi, Nobuyuki; Young-Woo Ok; Tae-Yeon Seong; Seong-Ju Park
May 2004
Applied Physics Letters;5/10/2004, Vol. 84 Issue 19, p3810
Academic Journal
ZnO quantum dots (QDs) have been fabricated by the growth of SiO2/ZnO films/Si substrate and subsequent rapid-thermal annealing in a N2 ambient. Transmission electron microscopy (TEM) results show that the ZnO QDs 3-7 nm in size are formed and embedded in the amorphous silicon oxide interfacial layer when annealed at 850 °C. Photoluminescence (PL) at room temperature from the 850 °C-annealed samples reveals only high-energy emission at about 3.37 eV, while PL at 10 K shows a broad spectra with a tail up to about 3.5 eV. The TEM and PL results indicate that the broad spectra are caused by the presence of the ZnO QDs and hence by the quantum confinement effect.


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