Single dot optical spectroscopy of silicon nanocrystals: Low temperature measure

2019-09-26 09:02:01

single emission nanocrystals DOTS dot

责任者: Sychugov, Ilya;Juhasz, Robert;Galeckas, Augustinas;Valenta, Jan;Linnros, Jan 单位: Dept. Microlectron. Info. Technol., Royal Institute of Technology(KTH), SE-16440 Kista-Stockholm, Sweden 来源出处: Optical Materials,2005,27(5):973-976 摘要: Single dot spectroscopy allows studying properties of a single nanocrystal avoiding inhomogeneous broadening of the emission band. Here, data obtained by this technique for Si nanocrystals fabricated by electron beam lithography, plasma etching and subsequent size-reduction by oxidation are presented. First, blinking (on-off intermittence) of the luminescence was observed for most individual nanocrystals, although some exhibited relatively stable luminescence. As a result of the quantum confinement effect spectra with different emission wavelengths for different nanocrystals were recorded. While at room temperature the full width at half-maximum of the nanocrystal emission peaks was measured to be [similar to] 100-150 meV, at 80 K the linewidth for some dots appeared to be about [similar to] 25 meV only. The observed temperature dependence of the homogeneous linewidth may lead to an understanding of the exciton-phonon interaction in indirect band-gap quantum dots. © 2004 Elsevier B.V. All rights reserved. 关键词: Nanostructured materials;Silicon;Semiconductor quantum dots;Spectroscopic analysis;Electron beam lithography;Plasma etching;Thermooxidation;Photoluminescence;Quantum efficiency;Charge coupled devices;Ultraviolet radiation;Single dot spectroscopy;Bandgap materials;Nanocrystals;Spectral resolution