Films minces à base de Si nanostructuré pour des cellules ...

Si-np and their agglomeration. For this purpose, a ML composed of 50 patterns of 3
nm SRSO-P15 and 3 nm-SiO 2 was grown. All the MLs in the following discussions
will be represented as 'Pattern number (t SRSOnm /t SiO2 nm)'. Prior to the study on
emission behaviours, the structure of our 50(3/3) ML is investigated to ensure the
sublayer thicknesses are as expected to form Si-np. Most of the studies unless specied
otherwise are done on the as-grown samples and the samples annealed at two
chosen annealing treatments : 1min-1000°C and 1h-1100°C. These two annealing
treatments are interesting since we assume that:
ˆ a Short Time Annealing (STA) at 1min-1000°C allows the completion of Si
seeds which grow with further annealing treatments and crystallize.
tel-00916300, version 1 - 10 Dec 2013
ˆ the Classical Annealing (CA) at 1h-1100°C almost completes the formation of
Si-np.
The intermediate annealing temperatures are analyzed if there is a need.
3.7.1 Structural analysis
(a) Fourier transform infrared spectroscopy and X-Ray Diraction
The Brewster incidence FTIR and the XRD spectra of the test sample 50(3/3) are
shown in gures 3.17a and 3.17b respectively.
(a) FTIR spectra.
(b) XRD Spectra.
Figure 3.17: Structural changes in 50(3/3) ML with annealing as investigated by (a)
Brewster incidence FTIR spectra and (b) XRD spectra.
It can be seen from the FTIR spectra that the LO 3 and TO 3 peaks shift towards
higher wavenumber. The intensity of the LO 4 -TO 4 peak decreases indicating
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