Characterization of CFx films plasma chemically deposited from C3F8/C2H2 precursors

The properties of a variety of plasma produced fluorocarbon (CFx) thin films are described. The project objectives were: (i) to explore the widest range of process parameters and properties, with an emphasis on comparative characterizations of wetting and mechanical properties. (ii) To develop effective interfacial bonding layers for films of 1 μm and more. (iii) To utilize safe, non-toxic, environmentally acceptable and relatively inexpensive precursor gases. Wetting and surface energy were studied by the dynamic advancing and receding contact angle method. These properties are interpreted in terms of the surface chemistry revealed by X-ray photoelectron spectroscopy and the morphology characterized by optical and atomic force microscopy. The mechanical properties were determined by micro- and nano-indentation and scratch testing. Finally, simple tests of resistance to pollution, handling and aging were carried out. The process–structure–properties relationships are discussed. Process parameters giving films displaying attractive combinations of wetting and mechanical properties are identified.