Treatment surfaces with atomic oxygen excited in dielectric barrier discharge plasma of O2 admixed to N2

Abstract

This paper describes the increase in surface energy of substrates by their treatment with gas composition generated in plasmas of DBD (Dielectric Barrier Discharge) in O2 admixed with N2. Operating gas dissociation and excitation was occurred in plasmas developed in two types of reactors of capacitively-coupled dielectric barrier configurations: coaxial cylindrical, and flat rectangular. The coaxial cylindrical type comprised an inner cylindrical electrode encapsulated in a ceramic sheath installed coaxially inside a cylindrical ceramic (quartz) tube passing through an annular outer electrode. Components of the flat rectangular type were a flat ceramic tube of a narrow rectangular cross section supplied with two flat electrodes mounted against one another outside of the long parallel walls of this tube. The operating gas, mixture of N2 and O2, was flowing in a completely insulated discharge gap formed between insulated electrodes of the devices with an average velocity of gas inlet of about 7 to 9 m/s. Dielectric barrier discharge plasma was excited in the operating gaps with a bipolar pulse voltage of about 6 kV for 2 ms at 50 kHz repetition rate applied to the electrodes of the coaxial device, and of about 14 kV for 7 ms at 30 kHz repetition rate for the flat linear device. A lifetime of excited to the 2s22p4(1S0) state in DBD plasma and streaming to the surfaces with a gas flow atomic oxygen, responsible presumably for treating surfaces, exceeded 10 ms in certain cases, that simplified its separation from DBD plasma and delivery to substrates. As it was found in particular, surfaces of glass and some of polymers revealed significant enhancement in wettability after treatment.

Superresolution imaging of single DNA molecules using stochastic photoblinking of minor groove and intercalating dyes

“…To achieve a suitable labeling density for superresolution imaging, dilutions of reagents were Coverslips were plasma cleaned prior to use to remove impurities and reduce autofluorescence. Coverslips were subjected to a high frequency plasma for 1 minute in a Harrick PDC-32G plasma cleaner, handled with forceps, and were used immediately after treatment, since the effects of plasma cleaning relax exponentially with a time constant of around 4 hours [19].…”

Computational fluid dynamics simulations of silicon μ-structure formation during excimer laser modification of silicon-nanoparticle layers

“…In consequence, there is no continuous sample heating and resolidified Si can be assumed between the pulses [8,33]. Therefore, to reduce the computational time, the time between melting intervals was Comparison of contact angles Θ of Si μ-cones on different substrates and corresponding literature surface energy values for the used substrates (silicon nitride (SiN), [36] glass, [37] aluminum (Al) [38] and tungsten (W) [39]). For the selected Si-NP layer thickness of 320 nm and laser energy density of 1.04 J cm −2 , the Si-NPs melt sequentially, and five pulses are required to completely melt the thin film (figure 3).…”

“…(a): Cross-sectional SEM image of Si μ-cones on a Ti/W coated glass substrate with indicated contact angle Θ. (b):Comparison of contact angles Θ of Si μ-cones on different substrates and corresponding literature surface energy values for the used substrates (silicon nitride (SiN),[36] glass,[37] aluminum (Al)[38] and tungsten (W)[39]).…”

Treatment of Metal and Textile Fabrics Surfaces Using Plasma

“…When equilibrium exists between ionization and recombination, the plasma will burn in a stable manner [28]. Minimum ionization energy of an electron is required to ionize an atom and if energy transfer due to the impact is less than the ionization energy, then the struck atom is excited [29].…”