Effect of plasma fluorination variables on the deposition and growth of partially fluorinated polymer over PMMA films

Abstract

Abstract:In this work, an investigation was made of the modification of film surface of Poly(methylmethacrylate) (PMMA) using the plasma polymerization technique. PMMA films 10 µm thick were obtained by Spin-Coating starting from a chloroform solution (15.36% w/w). The films were exposed to the plasma of CHF 3 at different gas pressures and exposure times to increase the thickness of fluorinated polymers onto PMMA films. The plasma fluorinated optical films were characterized by gravimetry, FTIR-ATR, contact angle of wetting, SEM and AFM. The surface fluorination of PMMA films can be inferred by the increase in contact angle under all experimental conditions, and confirmed with FTIR-ATR analysis. Gravimetry showed an increase of the fluorinated polymer layer over PMMA films, being 1.55 µm thick at 0.7 torr and 40 minutes of plasma exposure. The SEM analysis showed a well-defined layer of fluorinated polymer, with fluorine being detected in the EDS analysis. The film roughness for the fluorinated polymers was around of 200 Å, quite satisfactory for a 1.55 µm cladding.

Sulfur Hexafluoride (SF6) Plasma Treatment of Medical Grade Poly(methyl methacrylate)

“…As the sodium percentages are consistently higher than that of chlorine, other sodium-containing deposits are likely to be present. In previous works regarding gas fluorinated PMMA samples immersed in SAH (8 weeks), the EDS analysis indicated the presence of sodium chloride crystallites but a negligible calcium deposition [10,30]. This previous result could be attributed to the concentration of NaCl in the SAH being > ×50 higher than that calcium and phosphate.…”

Effect of solvents on the morphology of PMMA films fabricated by spin-coating

“…Giacon et al [3] showed that thickness for the fluorinated film around 0.57 μm was suitable for cladding of PMMA with core of 14 μm. While Padilha et al [20] observed 0.61 μm of fluorinated polymer at 0.7 torr and 20 min. In this present work, PMMA films treated with plasma showed low roughness at this plasma condition.…”

“…Padilha et al [20] studied the effect of plasma treatment on the deposition of films fluorinated over PMMA, the results showed that films treated using CHF 3 plasma obtained acceptable thickness for optical devices. Under these conditions, a profilemeter analysis has been carried out.…”

Fabrication and characterization of polymeric optical by plasma fluorination process

“…Previous work [11] showed the feasibility to use the CF 4 + H 2 plasma polymerization to modify the surface and reduce the refractive index of PMMA. XPS and FTIR-ATR analysis revealed that a thin layer of a partially fluorinated polymer was deposited on the PMMA films after plasma [12].…”

“…The cladding was a fluorinated polymer (0.6 m) produced by CHF 3 plasma polymerization (parallel plate reactor, 13.56 MHz) deposited under experimental conditions similar to those used in our previous work [12] and the core was a PMMA optical film (14 m) prepared by spin coating. The refractive index of the fluorinated film was characterized by ellipsometry and metricon prism coupler.…”