IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Thin Films Thursday Sessions
       Session TF+BI-ThM

Paper TF+BI-ThM7
Hot-Filament Chemical Vapor Deposition of Fluorocarbon-Organosilicon Copolymer Thin Films

Thursday, November 1, 2001, 10:20 am, Room 123

Session: Bioactive and Organic/Inorganic Thin Films
Presenter: S.K. Murthy, Massachusetts Institute of Technology
Authors: S.K. Murthy, Massachusetts Institute of Technology
K.K. Gleason, Massachusetts Institute of Technology
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Hot-filament chemical vapor deposition, a non-plasma technique, has been used to deposit copolymer thin films consisting of fluorocarbon (CF@sub 2@) groups and organosilicon groups (Si(CH@sub 3@)@sub 2@ - O) at rates of approximately 250 angstroms/min. The synthesis of such copolymers by solution chemistry techniques is difficult since one component (PTFE) is normally synthesized by free radical polymerization techniques and the other (PDMS) by ionic polymerization methods. The presence of covalent bonds between the fluorocarbon and organosilicon moieties in the thin films has been confirmed by Infrared, X-Ray Photoelectron (XPS) and solid-state @super 29@Si, @super 19@F, and @super 13@C Nuclear Magnetic Resonance (NMR) spectroscopy. These techniques also indicate retention of methyl groups from the siloxane precursor. The XPS data shows that all of the silicon present in the films is in the +2 oxidation state and that the ratio of silicon to CF@sub 2@ groups is approximately 1:0.86 based on atomic composition. Further, the NMR data suggest that the copolymer films are blocky in nature, consisting of networked chains having multiple fluorocarbon groups interspersed between siloxane groups. Atomic Force Microscopy of the films showed that the roughness of these copolymer films is in-between that of homopolymeric fluorocarbon and organosilicon films made by the same technique.