Hydrophobic treatment of organics against glass employing nonequilibrium atmospheric pressure pulsed plasmas with a mixture of CF4 and N2 gases

Abstract

A hydrophobic organics surface selectively against glass was realized by employing nonequilibrium atmospheric-pressure pulsed plasmas with a mixture of CF 4 and N 2 gases. The organic surface was drastically altered to have a high hydrophobicity, while the glass surface itself remained hydrophilic after the plasma treatment with the addition of a small amount of CF 4 to the N 2 gas. After 100 CF 4 / N 2 plasma treatments, no thin film deposition was observed on the organic material. To investigate the characteristics of the CF 4 / N 2 plasma, the exhaust gas from the plasma was measured by using ion attachment mass spectroscopy ͑IAMS͒. The IAMS spectrum indicated that the amounts of CF 3 and F radicals were increased drastically with increasing addition of CF 4 . A mechanism of the selective surface modification was clarified on a result of surface chemical bonding with the gas phase.

Surface Modification of a Regenerated Cellulose Film Using Low-Pressure Plasma Treatment with Various Reactive Gases

“…It could be said that O 2 plasma treatment allowed for homogeneous etching of the RC film contrary to N 2 plasma. After the treatment with CF 4 plasma for 60 s, the surface profile changed to one with broader mounds, and the RMS roughness increased from 14.5 to 24.1 nm, suggesting that the F and/or CF x radicals were generated by the dissociation of CF 4 and deposited on the surface of the RC film (Figures d and d) . This result agrees with the changes in chemical composition, as well as the surface wettability that is previously reported in this work.…”

Rapid Formation of Transparent Superhydrophobic Film on Glasses by He/CH4/C4F8Plasma Deposition at Atmospheric Pressure

“…However, most plasma sources except atmospheric pressure plasma require a vacuum system, which limits rapid multi‐fabrication. For this reason, atmospheric pressure plasma sources have been favored for modification of the surface properties . In atmospheric pressure plasma processing, the plasma conditions such as feed gas flow, power, and source types influence the result of surface treatments because both chemical and physical properties are dictated by the deposition of functional groups and surface morphology, which are affected by the plasma.…”

Comparative Study of the Surface Cleaning for Ar-/He-Based Plasma Jets at Atmospheric Pressure

“…It is possible to immediately continue processing the materials, and many studies have been carried out [9]- [12]. Plasma cleaning is aided by the use of gas mixtures containing He, Ar, air, or N 2 with the addition of small amounts of O 2 , H 2 , or CF 4 [13]- [16]. Which addition is used depends on the specific application.…”