Deposition of fluorocarbon film with 1,1,1,2-tetrafluoroethane pulsed plasma polymerization

• The pulsed plasma polymerized film obtains the super-hydrophobic characteristic.
• The Cassie–Baxter model analyzes the high water/air area fraction.
• The pulsed C2H2F4 plasma polymerization is suitable for polymeric material.
• The film surface analyses determine the carbon–fluorine characteristic.

The fluorocarbon films were synthesized by radio frequency pulsed 1, 1, 1, 2-tetrafluoroethane plasma polymerization using various duty cycles. The deposition rates and water contact angles were examined for radio frequency pulsed plasma polymerized fluorocarbon films. The film surface properties were also determined by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and scanning electron microscopy. For varying duty cycle from 100% to 10% in pulsed plasma process, the plasma polymerized film drastically changed the surface property. Specifically, it has been observed that modulated plasmas with the proper duty cycle of 10% lead to the formation of the super-hydrophobic film by static water contact angle value of 150°. The surface properties of fluorocarbon films were determined as the Cassie state. In the transmittance, UV–VIS transmission spectra showed that these radio frequency pulsed plasma polymerized coatings were transparent in visible light region. By adjusting duty cycles in relation to radio frequency pulsed plasma polymerization, the hydrophobicity of the resulting thin fluorocarbon films could be tuned.