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Organic films have been deposited by means of vacuum based techniques –polymer thermal degradation (“evaporation”) and polymer sputtering since the second half of the last century. The term “evaporation” means that a polymer degrade in a number of low molecular weight fragments. These are emitted into the space and condense on adjacent surfaces (substrates) producing amorphous polymer-like films. Later, an ionization-assisted evaporation method was used for deposition of polymer-like films (polyethylene, polytetrafluoroethylene and polyurea). Another technique called Surface Polymerization by Ion-Assisted Deposition (SPIAD) was developed for deposition e.g. polythiophene like films . In the UHV system the 3 T neutrals and mass-selected thiophene ions were co-deposited on the substrate. Recently, thermal degradation of polyimide with or without a glow discharge for deposition of polymer-like films was investigated.
In case of RF sputtering of conventional polymers positive ions bombard polymeric target with sufficient energy and create fragments of polymer chains that are emitted into the plasma volume. These fragments serve as precursors in plasma polymerization process. We are not discussing here a “conventional plasma polymerization” that uses a passage of an organic gas or vapor through a glow discharge.
Several polymer targets: PTFE (polytetrafluoroethylene), PE (polyethylene), PP (polypropylene), and PI (polyimide) were sputtered by means of RF planar magnetron. Deposition process was monitored by the optical emission spectroscopy and corpuscular diagnostics. The growing films were analyzed by means of in-situ FTIR, and subsequently transferred into the XPS apparatus. Ex situ RBS/ERDA analysis and the examination of morphology were performed by means of AFM and SEM.
Nanocomposite films have been also co-sputtered from the two RF magnetrons equipped with SiO2 or TiO2 and a polymer target, respectively. Basic properties of nanocomposite films SiOx/fluorocarbon plasma polymer and SiOx/hydrocarbon or TiOx/hydrocarbon plasma polymer are concisely described. In conclusion potential applications of the discussed films are outlined.
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