Our Surface Modification team is often asked about the benefits of low-pressure plasma treatments. Plasma offers many advantages to industries ranging from medical and biotech to aerospace and automotive. For the next few weeks, I’ll touch on some of the basics that are helpful to know when considering plasma treatment for your application.
Oxidizing species such as air, oxygen, water vapor, or nitrous oxide are often used as processing gases in low-pressure (vacuum) plasma systems to remove organic contaminates and to leave functional oxygen-containing groups on the surface of the device and/or material being treated. These groups greatly enhance wetting and improve the bond-strength of adhesives, inks or paints, tapes, encapsulation/potting resin, and coatings.
Reducing gas species such as hydrogen or methane (often mixed with argon, helium, or nitrogen) may be used to remove organic contamination from substrates that may be sensitive to oxidation. This chemistry may also be used to partially substitute hydrogen atoms for fluorine or oxygen on the surface of polymer substrates. The noble gas species, such as argon or helium, are chemically inert so they do not combine or become part of the surface chemistry. Instead, they transport energy to break chemical bonds in polymer chains. Broken polymer chains result in dangling bonds which recombine with other reactive sites, resulting in significant molecular restructuring and/or crosslinking. The creation of dangling bonds allows for chemical grafting reactions to occur.
Have questions on plasma processing? Consult our Experts to learn more.
Dave Biering