In this work we present some results of the treatment of polydimethylsiloxane(PDMS) surfaces using pulsed dielectric barrier discharge plasmas. The resultsof plasma treatment using different gases and mixtures, argon, argon plus watervapor, helium, helium plus water vapor, nitrogen and nitrogen plus water vapor,were compared testing the adhesion between two PDMS samples for each kind ofplasma. We also studied the water contact angle in function of plasma processtime of PDMS surfaces with each kind of plasma treatment. The plasma wascharacterized by optical emission spectroscopy (OES) to identify the emittingspecies and determine the plasma temperatures. The plasma temperature for eachprocess was estimated comparing the spectrum obtained by OES with the spectrumgenerated by SpecAir simulation code. Measurements of power delivered to theplasmas were also performed. As the results, all the process using differentgases show good adhesion efficacy between PDMS samples when long exposure time(larger than 150 seconds) is applied. However, when only a few discharges areapplied to PDMS samples the helium plasma process presented best results.Atomic Force Microscopy (AFM) analysis of PDMS samples treated with heliumplasma showed reduction in the surface roughness, which increase the surfacecontact area and improves the adhesion.
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