Plasma‐Polymerization of HMDSO Using an Atmospheric Pressure Dielectric Barrier Discharge

Abstract

In this work, an atmospheric pressure glow‐like dielectric barrier discharge in argon with small admixtures of hexamethyldisiloxane (HMDSO) is employed for the deposition of thin polydimethylsiloxane (PDMS) films. The effect of discharge power and feed composition (monomer concentration) on film properties has been investigated by means of contact angle measurements, Fourier‐Transform Infrared Spectroscopy (FT‐IR), and Atomic Force Microscopy (AFM). The results are described by defining a W/FM value, where W is the discharge power, F the monomer flow rate, and M is the molecular weight of the monomer. This paper shows that the deposition rate and the chemical composition of the deposited films are strongly affected by the W/FM value at which plasma‐polymerization is performed.

Development of nano-structured icephobic surfaces based on plasma polymerization /

“…Many studies showed that deposition time can lead to an increase in the thickness of the coating [77,78,89]. The results of 25 minute deposition time (contact angle and contact angle hysteresis) were satisfactory, however.…”

“…By increasing the monomer flow rate, the concentration of methyl groups can also increase. However, it may lead to coating delaminate [31,89].…”

“…27 Figure 11.13: Molecular structure of a) Acrylic acid (unsaturated), b) Perfluorohexane (linear saturated) and c) Octafluorotoluene (cyclic unsaturated) [65] .28 Figure 11.14: R.F. Variation of contact angles for the different plasma precursors deposited a) FAS-3, b) FAS-13, and c) FAS-17 [66] 29 Figure 11.15: AFM Images of a) untreated silicon wafer, b) PP-HMDSO coating deposited at 30 sec deposition and c) PP-HMDSO film at 5 min deposition [77]..... 32 Figure 11.16: Advancing and receding contact angle of PP-HMDSO film at different deposition times on a) wafer silicon b) polyethylene [77] 33 Figure 11.17: Contact angle of PP-Hexafluoropropylene coating on poly(vinyl chloride) tube as a function of deposition time [64] 34 Figure 11.18: FT-IR spectra of PP-HMDSO films deposited with different monomer concentrations (discharge power 9.5 W, film thickness 700 nm) [89] 35 Figure 11.19: SEM images of the coatings at a) 1, b) 3, c) 5, d) 8, e) 11, and f) 18 cm from the gas inlet [73] .....36 Figure 11.20: Static, advancing, and receding contact angle vs. axial position of samples from the gas inlet [73] • ..37 [95]. ...43 Figure 11.26: X-ray photoelectron spectroscopy F/C ratio of plasma-polymerized fluorocarbon coatings deposited on stainless steel as a function of immersion time in distilled water [105] 44 Figure 11.27: Atomic force microscopy images 2^2 (im 2 of plasma-polymerized thin coating after: (a) 0 week, (b) 1 week, (c) 2 weeks, (d) 3 weeks and (e) 4 weeks of ageing in D.I.…”

Nonequilibrium Atmospheric Plasma Deposition

“…The common operational mode of atmospheric pressure DBD is filamentary (Ref 54,(57)(58)(59)(60)(61)(62)(63)(64)(65)(66)(67)71), resulting in strong spatial nonuniformity of plasma chemistry that can alter the quality of the films. On the contrary, glow DBD modes (Ref 53,55,56,(68)(69)(70)72), sometimes, referred to as low current atmospheric pressure Townsend-like discharge or high current atmospheric pressure glow-like discharge, are expected to give high quality films. This uniform mode of DBD is observed for a very restricted set of parameters such as gas mixture, dissipated power, operational frequency, etc.…”

“…In Table 1, we list a set of works (Ref [53][54][55][56][57][58][59][60][61][62][63][64][65][66][67][68][69][70][71][72] showing the various possibilities investigated to deposit thin films by low power sources. The common operational mode of atmospheric pressure DBD is filamentary (Ref 54,(57)(58)(59)(60)(61)(62)(63)(64)(65)(66)(67)71), resulting in strong spatial nonuniformity of plasma chemistry that can alter the quality of the films.…”