Feasibility study of material surface treatment using an atmospheric large-area glow plasma

Application of atmospheric large-area plasma of a volume of 200 × 50 × 4 mm³ to various material surfaces was attempted for modification of surface properties. Based on the electrical and optical diagnostics, the plasma used for the treatment exhibited normal glow discharge characteristics with relatively low gas temperature, which might enable surface modification without thermal effect. Contact angle measurement showed that the plasma treatment, in general, changed surface characteristics such as wettability of paper, glass, and a silicon (Si) wafer from being hydrophobic to hydrophilic. In addition, ashing of the photoresist coated on a Si demonstrated that the measured ashing rate was found to vary depending on the plasma exposure time and the oxygen amount added to the argon supply gas. Based on the results, it is expected that the atmospheric plasma can be effectively utilized to some processes to which conventional low-pressure plasmas are employed.