Development of matrix-assisted pulsed laser evaporation (MAPLE) for deposition of disperse films of carbon nanoparticles and gold/nanoparticle composite films

Carbon nanopearls films were deposited onto silicon substrates using MAPLE. A 248 nm KrF excimer laser was directed onto a target consisting of ~ 150 nm-sized carbon nanopearls dispersed in a solvent solution and frozen in liquid nitrogen. The morphology of deposited carbon nanopearl films found to be influenced by matrix solvent, laser energy, repetition rate, background pressure, and substrate temperature. At ambient laboratory temperatures, the morphology of deposited films was characterized by highly concentrated areas of carbon nanopearls in the shape of hollow rings, caused by impingement of liquid droplets of the solvent/nanopearl suspension on the substrate surface followed by evaporation of the solvent. As the substrate temperature was increased, the size of the liquid droplets reaching the substrate surface decreased; however, the amount of material deposited via evaporation also decreased. The optimal deposition conditions were suggested and used for a hybrid process where laser ablation from frozen dispersion solution targets was combined with sputtering from gold targets. A nanocomposite coating consisting of carbon nanopearls encapsulated in a gold matrix was synthesized using MAPLE and magnetron sputtering simultaneously. This process makes it possible to synthesize nanocomposite films using a nanostructured dispersion solution.