On the Formation of IR-Light-Emitting Ge Nanocrystals in Ge:SiO2 Films
- Authors: Volodin V.A.1,2, Rui Z.2, Krivyakin G.K.1,2, Antonenko A.K.2, Stoffel M.3, Rinnert H.3, Vergnat M.3
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Affiliations:
- Institute of Semiconductor Physics, Siberian Branch, Russian Academy of Sciences
- Novosibirsk State University
- Université de Lorraine, Institut Jean Lamour UMR CNRS 7198
- Issue: Vol 52, No 9 (2018)
- Pages: 1178-1187
- Section: Microcrystalline, Nanocrystalline, Porous, and Composite Semiconductors
- URL: https://journals.rcsi.science/1063-7826/article/view/204050
- DOI: https://doi.org/10.1134/S1063782618090233
- ID: 204050
Cite item
Abstract
The study is concerned with light-emitting Ge nanocrystals formed during the annealing of Gex[SiO2]1 –x films produced by the high-vacuum cosputtering of germanium and quartz targets onto substrates at a temperature of 100°C. In accordance with the conditions of growth, the Ge molar fraction was varied from 10 to 40%. By means of electron microscopy and Raman spectroscopy, amorphous Ge nanoclusters ~4–5 nm in dimensions are detected in as-deposited films with a Ge content higher than 20 mol %. To crystallize amorphous nanoclusters, annealing at temperatures of up to 650°C is used. The kinetics of the crystallization of Ge nanoclusters is studied, and it is established that up to ~1/3 of the amorphous phase is retained in the system, supposedly at the interfaces between nanocrystals and the surrounding amorphous SiO2 matrix. It is found that, upon annealing in normal atmosphere, germanium nanoclusters are partially or completely oxidized (at a Ge molar fraction of 30% and smaller). An intense infrared photoluminescence signal from quantum-confined Ge nanocrystals and a visible photoluminescence signal defined by defect complexes (oxygen vacancy + excess Ge atoms) are observed.
About the authors
V. A. Volodin
Institute of Semiconductor Physics, Siberian Branch, Russian Academy of Sciences; Novosibirsk State University
Author for correspondence.
Email: volodin@isp.nsc.ru
Russian Federation, Novosibirsk, 630090; Novosibirsk, 630090
Zhang Rui
Novosibirsk State University
Email: volodin@isp.nsc.ru
Russian Federation, Novosibirsk, 630090
G. K. Krivyakin
Institute of Semiconductor Physics, Siberian Branch, Russian Academy of Sciences; Novosibirsk State University
Email: volodin@isp.nsc.ru
Russian Federation, Novosibirsk, 630090; Novosibirsk, 630090
A. Kh. Antonenko
Novosibirsk State University
Email: volodin@isp.nsc.ru
Russian Federation, Novosibirsk, 630090
M. Stoffel
Université de Lorraine, Institut Jean Lamour UMR CNRS 7198
Email: volodin@isp.nsc.ru
France, B.P. 70239, Vandœvre-lés-Nancy Cedex, 54506
H. Rinnert
Université de Lorraine, Institut Jean Lamour UMR CNRS 7198
Email: volodin@isp.nsc.ru
France, B.P. 70239, Vandœvre-lés-Nancy Cedex, 54506
M. Vergnat
Université de Lorraine, Institut Jean Lamour UMR CNRS 7198
Email: volodin@isp.nsc.ru
France, B.P. 70239, Vandœvre-lés-Nancy Cedex, 54506