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Abstract: In this paper, we report the spatially controlled dissolution of silver nanoparticles in irradiated SiO2 sol–gel films. The Ag nanoparticles have been formed in the sol–gel solution before the film deposition by adding Triton and ascorbic acid and also after the film deposition using a heat treatment at 700°C for few minutes or at 550°C for 6h in reducing atmosphere. Using a spectrometer, a new view white light interferometer and a micro-thermal analyzer, we demonstrate that the silver nanoparticles can be dissolved using a continuous black ray UV lamp or with a near-infrared (NIR) femtosecond laser, due to a significantly increase in the local temperature. We confirm that the micro-thermal analyzer can be used as a new tool to study the dissolution of metallic nanoparticles in thin film if located at the surface of the films. [ABSTRACT FROM AUTHOR]

Abstract: We report in this paper, results on the formation and dissolution of Cu-based nanoparticles in sol–gel SiO2 thin films using heat treatment and UV light exposure, respectively. Using UV–vis-NIR spectroscopy, we have shown that Cu2O nanoparticles can be generated by controlling the aging of the sol prior to film deposition while the Cu0 nanoparticles can be synthesized using a heat treatment in H2 atmosphere at 550°C for 6h. It has been also demonstrated that irradiation with an UV pulsed (Q-switched Nd:YAG) or continuous black ray UV lamp can dissolve these Cu-based nanoparticles with controlled, spatial selectivity. The mechanism of the dissolution process was found to be mainly thermal. Finally, we report a new analytical technique for detecting/confirming the presence of low densities of Cu nanoparticles in the films, based on a relative heat flow measurement of such films using a micro-thermal analyzer (e.g., TA Instruments μTA model 2990). [Copyright &y& Elsevier]