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

to equation 2.4, when X-ray beam strikes on a crystal at an angle θ, constructive
interference occurs only when the distance travelled by the X-rays scattered from
successive planes diers by an integer n of the wavelength and results in the diraction
pattern. In our case, the thin lms are usually composed of randomly oriented
nanocrystals and gure 2.6 shows a pictorial representation of Bragg's diraction
from one of the diracting nanocrystal. Each orientation of the crystal results in a
diraction peak at dierent angles (which is usually measured as 2θ in the experiments
for practical purposes), characteristic to the crystallographic structures of the
material.
tel-00916300, version 1 - 10 Dec 2013
Figure 2.6: Pictorial representation of Bragg's law.
Experimental set-up and working
The experiments were performed in grazing incidence using a Philips XPERT instrument
equipped with a copper anode to generate X-rays with λ = 1.5406 and
1.5444 angströms corresponding to the Cu-K α1 and K α2 lines respectively. Figure
2.7 shows a schematic representation of the experimental set-up in grazing geometry.
Figure 2.7: XRD- Illustration of working principle and experimental set-up.
Grazing incidence XRD is a technique suitable for the analysis of thin lms since
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