Physical Sputtering and Chemical Etching

Ablation of materials by the action of low-pressure luminous gas is an important factor that cannot be ignored in any process that utilizes luminous gas reactions. Ablation under consideration is not limited to the substrate material but also extends to materials used as an electrode and reactor wall. It is also important to recognize that the ablated materials could deposit in different locations, as described in Chapter 10. 

Unexpected elements in a plasma polymer often are due to the redeposition of ablated materials. The presence of nitrogen found in a plasma polymer of a monomer that does not contain nitrogen can be traced to contamination of the reactor, which has been used for plasma polymerization of nitrogen-containing monomers [1]. The ablation of electrode material has been utilized to create a graded metal-polymer and polymer-metal interfaces to obtain an excellent adhesion [2,3]. Ablation, therefore, could be utilized in a beneficial way in the engineering of interfaces if we know the nature of ablation and how to control it. 

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