Investigation of Photoluminescence Mechanisms from SiO2/Si:SiO2/SiO2 Structures in Weak Quantum Confined Regime by Deconvolution of Photoluminescence Spectra

Date

2016-04-01

Author

TUĞAY, EVRİN
Turan, Raşit

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

157
views

0
downloads

Si nanocrystals embedded in SiO2 matrix were prepared by co-sputtering method followed by a post annealing process in N-2 ambient. By fixing sputtering parameters, the effects of annealing time and annealing temperature on the optical properties of Si nanocrystals are investigated. Origin and evolution of the photoluminescence (PL) in weak quantum confinement regime are discussed in the light of X-ray diffraction, Fourier transform infrared, and temperature dependent photoluminescence measurements. For all samples, the PL peaks tend to decompose to four Gaussian peaks in which attributed to the radiative defects in SiO2 matrix, nc-Si/SiO2 interface related localized defects, localized states in the amorphous Si band gap and quantum confinement of excitons in smaller nanocrystals. Considering the observation of luminescence and its decomposition tendency in nanocrystals with average sizes larger than exciton's Bohr radius the necessity to distinguish between the role of smaller and larger nanocrystals in the PL mechanisms is discussed. Furthermore, possible origin of the interface related localized states in particular Si=O double bonds in the nc-Si/SiO2 interface and that of radiative defects in SiO2 matrix are discussed.

Subject Keywords

Defects, Quantum confinement, Si Nanocrystals, Photoluminescence

URI

https://hdl.handle.net/11511/32888

Journal

JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY

DOI

https://doi.org/10.1166/jnn.2016.10863

Collections

Department of Physics, Article

Suggestions

OpenMETU
Core

Influence of Ge content and annealing conditions on the PL properties of nc-Si1-xGex embedded in SiO2 matrix in weak quantum confined regime TUĞAY, EVRİN; Ilday, Serim; Turan, Raşit; Finstad, Treje G. (2014-11-01) Fabrication of Si (nc-Si), Ge (nc-Ge), and Si1-xGex (nc-Si1-xGex) nanocrystals embedded in SiO2 matrix is achieved by thermal annealing of magnetron-sputtered thin films. Effects of annealing conditions, namely duration and temperature, as well as Ge content on the photoluminescence properties are investigated. Origin and evolution of the photoluminescence signal in the weak quantum confinement regime are discussed. It is found that photoluminescence signals can be decomposed into four Gaussian peaks origin...
Numerical investigation of coupled heat and mass transfer inside the adsorbent bed of an adsorption cooling unit Solmus, Ismail; Rees, D. Andrew S.; Yamali, Cemil; Baker, Derek Keıth; KAFTANOĞLU, BİLGİN (2012-05-01) In this study, the influence of several design parameters on the transient distributions of temperature, pressure and amount adsorbed in the radial direction of a cylindrical adsorbent bed of an adsorption cooling unit using silica gel/water have been investigated numerically. For this purpose, a transient one-dimensional local thermal non-equilibrium model that accounts for both internal and external mass transfer resistances has been developed using the local volume averaging method. For the conditions in...
Analysis of slot coupled microstrip patch antennas Ballıkaya, Elif; Aydın Çivi, Hatice Özlem; Department of Electrical and Electronics Engineering (2007) Method of Moments (MoM)/Green’s function formulation is developed for the analysis of electromagnetic radiation from planar rectangular microstrip antennas with different feeding techniques. Investigated structures are microstrip line fed patch antenna, proximity coupled patch antenna and slot coupled patch antenna. For all these structures equivalent problems are defined. Then, integral equations where currents are the unknowns are obtained from boundary conditions and by using spectral domain representati...
Characterization of defect states in Ga-rich gallium arsenide crystals by thermally stimulated current YILDIRIM, TACETTİN; Hasanlı, Nızamı; TÜZEMEN, Sebahattin (2018-06-01) The trap levels in Ga-rich GaAs crystals were studied in the temperature range of 10-300 K using thermally stimulated currents (TSC) technique. During the experiments we utilized a constant heating rate of 0.2 K/s. Experimental evidence is found for two electron trapping centers in the crystal with activation energies of 44 and 50 meV. The analysis of the experimental TSC curve suggests slow retrapping. The capture cross sections of the traps were determined as 8.8 x 10(-25) and 1.0 x 10(-25) cm(2) with con...
Determination of trapping parameters of thermoluminescent glow peaks of semiconducting Tl2Ga2S3Se crystals IŞIK, MEHMET; YILDIRIM, TACETTİN; Hasanlı, Nızamı (2015-07-01) Thermoluminescence (TL) properties of Tl2Ga2S3Se layered single crystals were researched in the temperature range of 290-770 K. U glow curve exhibited two peaks with maximum temperatures of similar to 373 and 478 K. Curve fitting, initial rise and peak shape methods were used to determine the activation energies of the trapping centers associated with these peaks. Applied methods were in good agreement with the energies of 780 and 950 meV. Capture cross sections and attempt-to-escape frequencies of the trap...

Citation Formats

E. TUĞAY and R. Turan, “Investigation of Photoluminescence Mechanisms from SiO2/Si:SiO2/SiO2 Structures in Weak Quantum Confined Regime by Deconvolution of Photoluminescence Spectra,” JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY, pp. 4052–4064, 2016, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/32888.