Abstract :
Plasma-assisted functional films have significant potential in various engineering applications. They can be tailored to impart
desired properties by bonding specific molecular groups to the substrate surface. The aim of this investigation was to develop a
fundamental understanding of the atomic level growth, coverage and functional effectiveness of plasma nano-films on flat
surfaces and to explore their application-potential for complex and uneven shaped nano-materials. In this paper, results on
plasma-assisted nano-scale fluorocarbon films, which are known for imparting inertness or hydrophobicity to the surface, will be
discussed. The film deposition was studied as a function of time on flat single crystal surfaces of silicon, sapphire and graphite,
using microwave plasma. X-ray photoelectron spectroscopy (XPS) was used for detailed study of composition and chemistry of
the substrate and coating atoms, at all stages of deposition. Atomic force microscopy (AFM) was performed in parallel to study
the coverage and growth morphology of these films at each stage. Combined XPS and AFM results indicated complete coverage
of all the substrates at the nanometer scale. It was also shown that these films grew in a layer-by-layer fashion. The nano-films
were also applied to complex and uneven shaped nano-structured and porous materials, such as microcellular porous foam and
nano fibers. It was seen that these nano-films can be a viable approach for effective surface modification of complex or uneven
shaped nano-materials.
