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

Figure 4.15: Absorption coecient spectra of Si 3 N 4 and SRSN samples.
tel-00916300, version 1 - 10 Dec 2013
4.4 Summary
SiN x materials were grown by two dierent deposition approaches: Reactive sputtering
and Co-sputtering. Three kinds of SiN x layers were grown: N-rich silicon
nitride (NRSN), Si 3 N 4 and Si-rich silicon nitride (SRSN). It was demonstrated that
the refractive index of the layer is the ruling factor and the deposition approaches
do not inuence the material properties of these layers.
NRSN:
NRSN material was grown by sputtering Si 3 N 4 cathode reactively under N 2 plasma.
FTIR and refractive index studies conrm this layer is N-rich.
Si 3 N 4 :
Stochiometric layer was grown by sputtering Si 3 N 4 cathode reactively under N 2
plasma. The refractive index and FTIR investigations indicate that the grown layer
is Si 3 N 4 . The material exhibits low PL emission which increases upon annealing
reaching the highest for 1h-1100°C (CA). The material shows a low absorption that
increases with energies.
SRSN:
SRSN layers with various refractive indices were investigated. It was shown that
by using appropriate r N in the rst deposition approach orP Si in the second one,
we can tune SiN x composition close to Si 3 N 4 or pure Si layers. The SRSN layers
grown by both the deposition approaches have similar trend in structural and optical
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