Kinetics of Ag nanoparticle growth in thick SiO2 films: An in situ optical assessment of Ostwald ripening

Significant progress in understanding physico-chemical changes of noble metal species embedded in dielectrics can be achieved from the real-time monitoring of material optical properties during processing. In this work, in situ optical microspectroscopy is employed in a real-time assessment of the kinetics of Ag nanoparticle (NP) growth in the Ostwald ripening stage for NPs embedded in thick SiO2 films on soda glass, heat-treated in air atmosphere. The remarkable plasmonic evolution allows for following the variation in NP size in the framework of Mie extinction and crystal growth theories. An Arrhenius-type analysis yields an activation energy of 1.8 eV in association to aforementioned regime of NP growth. The data is discussed in the context of the atmosphere/film/substrate physico-chemical interactions alongside with previously reported results obtained by the proposed novel application of in situ optical microspectroscopy.