Detailed investigation of the influence of the process parameters on the nano-morphology of Ag deposited on SiC by radio-frequency sputtering

In this work, a detailed study of the influence of the synthesis parameters (deposition time t and emission current I) on the morphological properties of Ag nanoparticles sputter-deposited on silicon carbide is carried out. Using the atomic force microscopy technique, we analyzed the evolution of several structural characteristics as a function both of t and I: the length and width of the Ag nanoparticles, the number of nanoparticles per unit area, the nanoparticles' fraction of the covered area, and the roughness of the resulting Ag film. Using consolidated theoretical frameworks and fitting approaches, the relations between such quantities and the process parameters t and I were established. In particular, the application of the interrupted coalescence model allowed us to evaluate the critical mean island diameter for the partial coalescence process; the dynamic scaling theories of growing interfaces lead, instead, to the determination of the dynamic scaling, growth, and roughness exponents (the values of which suggest a conservative growth process of the islands in which the atomic surface diffusion plays a key role). Finally, the Avrami approach to the study of the evolution of the fraction of area covered by the Ag islands allowed us to evaluate the Avrami exponent. (C) 2011 American Institute of Physics. [doi:10.1063/1.3626072]