Fabrication of oleophobic fluorocarbon film by 13.56 MHz CH 2 F 2 /Ar plasma chemical vapor deposition

Abstract In order to control of the surface properties to create the oleophobic fluorocarbon film, this study reported the influence of low pressure CH 2 F 2 /Ar plasma processing on oil repellent thin film growth. Difluoromethane (CH 2 F 2 )/argon (Ar) gas mixture was used to generate low pressure plasma with radio frequency power at 13.56 MHz for fabrication of oleophobic fluorocarbon coatings. The surface characteristics of the CH 2 F 2 /Ar plasma-deposited films were studied by static contact angle measurement (CA), atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The effects of CH 2 F 2 /Ar plasma on the surface characteristics of the plasma-deposited films were investigated as a function of the CH 2 F 2 content. The fluorocarbon coating prepared under optimized experimental parameters exhibited the glycerol contact angle greater than 140°, confirming the oleophobic property of the coating. XPS revealed that plasma-deposited films obtained contain mainly CH, CF, C―CF x , and CF 2 species. In addition, AFM analysis shows that possible ion bombardment from CH 2 F 2 /Ar plasma can increase surface roughness. The combination of the low surface energy CF x species and the rough surface morphology successfully form the oleophobic CH 2 F 2 /Ar plasma-deposited film.