Limits...
Effect of the Nd content on the structural and photoluminescence properties of silicon-rich silicon dioxide thin films.

Debieu O, Cardin J, Portier X, Gourbilleau F - Nanoscale Res Lett (2011)

Bottom Line: Under non-resonant excitation at 488 nm, our Nd-doped SRSO films simultaneously exhibited PL from Si-np and Nd3+ demonstrating the efficient energy transfer between Si-np and Nd3+ and the sensitizing effect of Si-np.Moreover, the presence of Nd-oxide nanocrystals in the highest Nd-doped sample was established by XRD.It is, therefore, suggested that the Nd clustering, as well as disorder, are responsible for the concentration quenching of the PL of Nd3+.

View Article: PubMed Central - HTML - PubMed

Affiliation: CIMAP, UMR CNRS/CEA/ENSICAEN/UCBN, Ensicaen 6 Bd Maréchal Juin, 14050 Caen Cedex 4, France. fabrice.gourbilleau@ensicaen.fr.

ABSTRACT
In this article, the microstructure and photoluminescence (PL) properties of Nd-doped silicon-rich silicon oxide (SRSO) are reported as a function of the annealing temperature and the Nd concentration. The thin films, which were grown on Si substrates by reactive magnetron co-sputtering, contain the same Si excess as determined by Rutherford backscattering spectrometry. Fourier transform infrared (FTIR) spectra show that a phase separation occurs during the annealing because of the condensation of the Si excess resulting in the formation of silicon nanoparticles (Si-np) as detected by high-resolution transmission electron microscopy and X-ray diffraction (XRD) measurements. Under non-resonant excitation at 488 nm, our Nd-doped SRSO films simultaneously exhibited PL from Si-np and Nd3+ demonstrating the efficient energy transfer between Si-np and Nd3+ and the sensitizing effect of Si-np. Upon increasing the Nd concentration from 0.08 to 4.9 at.%, our samples revealed a progressive quenching of the Nd3+ PL which can be correlated with the concomitant increase of disorder within the host matrix as shown by FTIR experiments. Moreover, the presence of Nd-oxide nanocrystals in the highest Nd-doped sample was established by XRD. It is, therefore, suggested that the Nd clustering, as well as disorder, are responsible for the concentration quenching of the PL of Nd3+.

No MeSH data available.


Related in: MedlinePlus

Evolutions of the positions of the LO3 and TO3 peaks, and the LO3/TO3 intensity ratio, as a function of the annealing temperature.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC3211213&req=5

Figure 2: Evolutions of the positions of the LO3 and TO3 peaks, and the LO3/TO3 intensity ratio, as a function of the annealing temperature.

Mentions: Figure 2a shows the evolution of the positions of the LO3 and TO3 vibration modes, and the LO3/TO3 intensity ratio, as a function of the annealing temperature. One can observe that, while the annealing temperature was increased, the TO3 and LO3 peaks' positions progressively shifted to higher wavenumbers toward their respective stoichiometric positions. It is explained by the phase separation that results in the formation of Si-np [18,19]. The increase of the LO3 band intensity (see Figure 2b) is related to the increase of the number of Si-O-Si bonds at the SiOx/Si-np interface [19,20], i.e., the increase of the density of Si-np [21].


Effect of the Nd content on the structural and photoluminescence properties of silicon-rich silicon dioxide thin films.

Debieu O, Cardin J, Portier X, Gourbilleau F - Nanoscale Res Lett (2011)

Evolutions of the positions of the LO3 and TO3 peaks, and the LO3/TO3 intensity ratio, as a function of the annealing temperature.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3211213&req=5

Figure 2: Evolutions of the positions of the LO3 and TO3 peaks, and the LO3/TO3 intensity ratio, as a function of the annealing temperature.
Mentions: Figure 2a shows the evolution of the positions of the LO3 and TO3 vibration modes, and the LO3/TO3 intensity ratio, as a function of the annealing temperature. One can observe that, while the annealing temperature was increased, the TO3 and LO3 peaks' positions progressively shifted to higher wavenumbers toward their respective stoichiometric positions. It is explained by the phase separation that results in the formation of Si-np [18,19]. The increase of the LO3 band intensity (see Figure 2b) is related to the increase of the number of Si-O-Si bonds at the SiOx/Si-np interface [19,20], i.e., the increase of the density of Si-np [21].

Bottom Line: Under non-resonant excitation at 488 nm, our Nd-doped SRSO films simultaneously exhibited PL from Si-np and Nd3+ demonstrating the efficient energy transfer between Si-np and Nd3+ and the sensitizing effect of Si-np.Moreover, the presence of Nd-oxide nanocrystals in the highest Nd-doped sample was established by XRD.It is, therefore, suggested that the Nd clustering, as well as disorder, are responsible for the concentration quenching of the PL of Nd3+.

View Article: PubMed Central - HTML - PubMed

Affiliation: CIMAP, UMR CNRS/CEA/ENSICAEN/UCBN, Ensicaen 6 Bd Maréchal Juin, 14050 Caen Cedex 4, France. fabrice.gourbilleau@ensicaen.fr.

ABSTRACT
In this article, the microstructure and photoluminescence (PL) properties of Nd-doped silicon-rich silicon oxide (SRSO) are reported as a function of the annealing temperature and the Nd concentration. The thin films, which were grown on Si substrates by reactive magnetron co-sputtering, contain the same Si excess as determined by Rutherford backscattering spectrometry. Fourier transform infrared (FTIR) spectra show that a phase separation occurs during the annealing because of the condensation of the Si excess resulting in the formation of silicon nanoparticles (Si-np) as detected by high-resolution transmission electron microscopy and X-ray diffraction (XRD) measurements. Under non-resonant excitation at 488 nm, our Nd-doped SRSO films simultaneously exhibited PL from Si-np and Nd3+ demonstrating the efficient energy transfer between Si-np and Nd3+ and the sensitizing effect of Si-np. Upon increasing the Nd concentration from 0.08 to 4.9 at.%, our samples revealed a progressive quenching of the Nd3+ PL which can be correlated with the concomitant increase of disorder within the host matrix as shown by FTIR experiments. Moreover, the presence of Nd-oxide nanocrystals in the highest Nd-doped sample was established by XRD. It is, therefore, suggested that the Nd clustering, as well as disorder, are responsible for the concentration quenching of the PL of Nd3+.

No MeSH data available.


Related in: MedlinePlus