Fluorinated materials, plasma polymerization

In this section the identification of various structural features from the measured binding energies of the core level electrons is discussed. Examples have been chosen in the areas of (a) plasma polymerization of fluorinated materials and (b) surface oxidation of polymers, to encompass both fluorine-containing and oxygen-containing systems. 

Plasma Polymerization of Fluorinated Materials. Figure 8 shows the Cls and FIs binding energies measured for the linear fluoropolymers (.8). While the shifts in binding energy of the FIs levels are relatively small, the shift in the binding energy of the Cls levels induced by fluorine as a substituent is relatively... 

The XPS data reveal that a considerable degree of rearrangement of the injected fluorocarbon is involved in the plasma polymerization process. The relative quantities of CF, CF2, CF and non-fluorine substituted features are readily monitored by XPS and show a strong dependence on the injected fluorocarbon. As the fluorine content of the injected material decreases so does that of the polymer. Table 2 lists the measured F/C stoichio-... 

Most of these discussions regarding fluorine contamination of aluminum surfaces have focused on the conversion of aluminum oxide to fluoride or oxyfluoride. Evidence for similar conversions was included, and in extreme cases conversion to aluminum bonding quite similar to that in AIF3 was found. However, the poor adhesion of the samples skipping the O2 plasma treatment is related not to the fluorine contamination as such, but rather to the carbonaceous nature of the adsorbed materials, which is subjected to the plasma polymerization of TMS. Oxygen plasma cleaning removes this carbonaceous component, while the surface fluorine concentration is enhanced. 

The Incorporation of metals Into polymer films produced by plasma techniques Is an attractive prospect since It can be envisaged that careful choice of the metal and organic phases, and close control of the overall composition of the product would greatly extend the scope of these plasma polymerized materials In, for example, electrical, magnetic and optical applications. In a previous paper (1) we have outlined a convenient method for the preparation of such materials derived from fluorinated monomers by simultaneous chemical plasma etching and polymerization in the same system. 

The close similarity of the spectra for these three examples (Figure 2) suggests that in all cases, irrespective of the mechanism of removal of material from the cathode or the nature of the cathode material, the polymer matrix formed at the film forming electrode is essentially the same. Furthermore, the overall band profile of the Cis spectra and fluorine/carbon stoichiometries are strikingly similar to those which have previously been reported in the literature for the polymer produced in the plasma polymerization of tetrafluoroethylene ( ). 

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