Please use this identifier to cite or link to this item: http://hdl.handle.net/2445/24866
Title: Optical-geometrical effects on the photoluminescence spectra of Si nanocrystals embedded in SiO2
Author: Ferre, R. (Rafael)
Garrido Fernández, Blas
Pellegrino, Paolo
Perálvarez Barrera, Mariano José
García Favrot, Cristina
Moreno Pastor, José Antonio
Carreras, Josep
Morante i Lleonart, Joan Ramon
Keywords: Propietats òptiques
Nanocristalls
Matèria condensada
Luminescència
Cristal·lografia
Optical properties
Nanocrystals
Condensed matter
Luminescence
Crystallography
Issue Date: 31-Oct-2005
Publisher: American Institute of Physics
Abstract: We demonstrate that thickness, optical constants, and details of the multilayer stack, together with the detection setting, strongly influence the photoluminescence spectra of Si nanocrystals embedded in SiO2. Due to multiple reflections of the visible light against the opaque silicon substrate, an interference pattern is built inside the oxide layer, which is responsible for the modifications in the measured spectra. This interference effect is complicated by the depth dependence of (i) the intensity of the excitation laser and (ii) the concentration of the emitting nanocrystals. These variations can give rise to apparent features in the recorded spectra, such as peak shifts, satellite shoulders, and even splittings, which can be mistaken as intrinsic material features. Thus, they can give rise to an erroneous attribution of optical bands or estimate of the average particle size, while they are only optical-geometrical artifacts. We have analyzed these effects as a function of material composition (Si excess fraction) and thickness, and also evaluated how the geometry of the detection setup affects the measurements. To correct the experimental photoluminescence spectra and extract the true spectral shape of the emission from Si nanocrystals, we have developed an algorithm based on a modulation function, which depends on both the multilayer sequence and the experimental configuration. This procedure can be easily extended to other heterogeneous systems.
Note: Reproducció del document publicat a: http://dx.doi.org/10.1063/1.2115100
It is part of: Journal of Applied Physics, 2005, vol. 98, núm. 8, p. 84319-1-84319-7
Related resource: http://dx.doi.org/10.1063/1.2115100
URI: http://hdl.handle.net/2445/24866
ISSN: 0021-8979
Appears in Collections:Articles publicats en revistes (Electrònica)

Files in This Item:
File Description SizeFormat 
528035.pdf238.06 kBAdobe PDFView/Open


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.