Ph. D. THESIS 2009

a b
Figure 14. Gold lines fabricated by laser in thick film of: a) a PSS aqueous
solution of gold salt at 30 mW; b) a PSS, gold salt and ammonium ferric citrate
aqueous solution of in 40-50 mW range.
It is therefore important to study the photochemical reactions of gold salt in
polymer matrices. Thus, we created a chemical system that contains
tetrachloroauric acid as active specie and ammonium ferric citrate as sensitiser,
dispersed into a PSS matrix. The structures are thiner and more regular by
adding of sensitizer and required less energy to be written, as can be seen in
Figure 14b.
That means PSS induces the decrease of size and number of the nanoparticles
generated by photoreduction by reducing the reaction rate. The contribution of
the polymer film in the photoreduction reaction is not yet elucidated.
4.3.2. Double-line effect in thin PSS matrix
The TPA photoreduction process in thin films allows us to fabricate various
kinds of 2D structures such as nanodots and nanowires networks. Within our
research we have studied the fabrication of metallic wires with dimensions
varying from a few hundred nanometers to one micron for their widths, and
ranging from a few to several hundred microns for their lengths (see figure
15a).
a b
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