Plasma pretreatment, oxygen-hydrogen

The analysis was done on a fresh layer after sputtering off the very thin air-contaminated layer. All samples were pretreated with oxygen and hydrogen plasma. 

Surface conditioning by plasma pretreatment with oxygen and hydrogen is a crucial factor in obtaining very strong bonding at the interface between the substrate and composite plasma polymer film as a preplate for metallization. 

Operation (partly) in vacuum. Reactive gases (oxygen, hydrogen, fluorine), which are transferred into an energy-rich state (plasma)by microwave stimulation with the possibility of chemical surface modification, are fed into the plasma chamber with the adherends to be pretreated. 

Bertrand et al. have studied the influence of hydrogen plasma excited by means of microwaves at 2.45 GHz to native oxide films on stainless steel and aluminum. Using in situ IR-ellipsometry, it could be shown that the native oxide on stainless steel was almost completely reduced in a hydrogen plasma. In contradiction to this, the aluminum surface was more resistant and only the outermost hydroxylated part of the oxide layer could be reduced. It was also observed that a dense oxide layer could be grown on the pretreated steel surface by subsequent oxygen plasma [222]. 

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