| Autor: |
Keita, A.-S., En Naciri, A., Battie, Y., Delachat, F., Carrada, M., Ferblantier, G., Slaoui, A. |
| Předmět: |
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| Zdroj: |
Journal of Applied Physics; 2014, Vol. 116 Issue 10, p1-12, 12p, 1 Color Photograph, 1 Black and White Photograph, 3 Charts, 5 Graphs |
| Abstrakt: |
We report on a comparative study between dielectric functions of Si nanoparticles (Si-NPs) obtained from Bruggeman effective medium approximation (BEMA), Maxwell-Garnett (MG), and a modified Maxwell-Garnett (MMG) models. Unlike BEMA and MG, a size-distribution dependent dielectric function of Si-NPs is considered in the introduced MMG model. We show that the standard deviation σ of a size distribution can be evaluated by analyzing the imaginary part of the dielectric functions of Si-NPs extracted from BEMA and MMG. In order to demonstrate this, several samples composed of Si-NPs embedded in silicon-rich silicon nitride are investigated by spectroscopic ellipsometry over the photon energy range varying between 2 and 4 eV. Assuming a lognormal size distribution of the Si nanoparticles, it is evidenced that the parameter σ ranges between 1.15 and 1.35. The values of size dispersion deduced by this methodology are in good agreement with TEM observations. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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