Plasma Discharge and Energetic Ions with Materials Surface

Interaction of Plasma Discharge and Energetic Ions with Materials Surface 

The surface analytical techniques mentioned above provide wealth information on the composition and structure of polymer surfaee and changes resulting from modification by plasma discharge. It should be however stressed that, despite of broad spectrum of analytical techniques available, the information is not sufficient to understand all imderlying proeesses in their eomplexity. Espeeially, it is the case of plasma treatment when the interaetions of many plasma eonstituents with polymer surface may play a role. Existing theoretical models are restricted to some specific cases and they usually deseribe only some part of the proeess. 

The ionization and excitation may lead to chemical bond cleavage and production of highly reactive species, free radicals, ions and molecular fragments, which subsequently interact with each other and at last stable degradation products are created. This complex sequence of processes can deliberately be divided into two basic phases, the initial physical phase, in which the ion energy is dissipated to electrons and atoms, and the chemical one comprising interaction of the reaetive species and production of the final stable products. 

The thickness of modified surface layer is determined by ion projected range Rp, measured in the direction of the sample surface normal. 

Two kinds of degradation products are in principle created, low mass species created by macromolecular chain scission and two- to three dimensional structures produced by macromolecule cross-linking (mediated by free radical reactions). 

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