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

tel-00916300, version 1 - 10 Dec 2013
2.1 Photo of the AJA Sputter chamber with glowing plasma and the
diagrammatic representation of various processes during sputtering. . 32
2.2 Illustration of sample fabrication methods. . . . . . . . . . . . . . . . 33
2.3 Dierent types of molecular vibrations. . . . . . . . . . . . . . . . . . 35
2.4 (a) Schematic representation of FTIR set-up and (b) Interferogram
to Fourier transformed spectra. . . . . . . . . . . . . . . . . . . . . . 36
2.5 Typical FTIR spectra of SiO 2 which is decomposed into three and
ve gaussians in the normal incidence and Brewster incidence spectra
respectively. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
2.6 Pictorial representation of Bragg's law. . . . . . . . . . . . . . . . . 39
2.7 XRD- Illustration of working principle and experimental set-up. . . . 39
2.8 A typical example of XRD spectrum taken from Si-based multilayer
containing Si nanocrystals. . . . . . . . . . . . . . . . . . . . . . . . . 40
2.9 Schematic diagram of XRR set-up and the two modes of measurement. 42
2.10 A typical XRR spectrum obtained from SRSO/SRSN ML with a
zoom of the interferences leading to total thickness determination
in the inset. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
2.11 Illustration of scattering of light and Raman shift. . . . . . . . . . . 44
2.12 Raman spectrometer-Schematic representation. . . . . . . . . . . . . 45
2.13 Typical Raman spectra of the substrates used in this thesis. . . . . . 45
2.14 Schematic representation of light microscope, transmission electron
microscope (TEM) and energy ltered TEM (EFTEM). . . . . . . . . 46
2.15 (a). Extraction of a silicon post using the Lift-out method. The
sample has been milled with the help of a FIB in order to extract
a strip of material. (b). The strip is shaped in a post and welded
onto a steel needle (platinum weld). (c-e). Successive annular milling
steps permit to obtain a very sharp tip which curvature radius does
not exceed 50nm. (Images from M. Roussel, GPM Rouen) . . . . . . 50
2.16 Schematic diagram of principle and experimental set-up of an ellipsometer.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
2.17 Step 1 and 2 of ellipsometry modelling. . . . . . . . . . . . . . . . . 54
2.18 Step 3 and Step 4 of ellipsometry modelling. . . . . . . . . . . . . . 55
2.19 Illustration of excitation and de-excitation processes. . . . . . . . . . 56
2.20 Schematic diagram of the photoluminescence experimental set-up. . . 57
2.21 PL spectra before and after correcting to spectral response.λ excitation =
488 nm. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
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