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Dense hydrogenated silicon nitride (SiNx:H) layers for photovoltaics are made by Atmospheric Pressure Plasma Enhanced Chemical Vapor Deposition (AP‐PECVD). The dependence of morphology, chemical, optical and passivation properties of the thin films on the plasma reactor configuration, the mode of homogeneous DBD (glow, Townsend, RF, nano pulsed) and the SiH4/NH3 gas flow ratio are investigated. Avoiding gas recirculation, improving thin film homogeneity through the electrode length and the plasma modulation appear as key points. Silicon solar cells made with AP‐PECVD SiN antireflective coating have the same efficiency as standard low pressure PECVD cells, showing the great potential of AP‐PECVD.

This paper describes an optical setup built to record Fourier transform infrared (FTIR) absorption spectra in an atmospheric pressure plasma with a spatial resolution of 2 mm. The overall system consisted of three basic parts: (1) optical components located within the FTIR sample compartment, making it possible to define the size of the infrared beam (2 mm × 2 mm over a path length of 50 mm) imaged at the site of the plasma by (2) an optical interface positioned between the spectrometer and the plasma reactor. Once through the plasma region, (3) a retro-reflector module, located behind the plasma reactor, redirected the infrared beam coincident to the incident path up to a 45° beamsplitter to reflect the beam toward a narrow-band mercury-cadmium-telluride detector. The antireflective plasma-coating experiments performed with ammonia and silane demonstrated that it was possible to quantify 42 and 2 ppm of these species in argon, respectively. In the case of ammonia, this was approximately three times less than this gas concentration typically used in plasma coating experiments while the silane limit of quantification was 35 times lower. Moreover, 70% of the incoming infrared radiation was focused within a 2 mm width at the site of the plasma, in reasonable agreement with the expected spatial resolution. The possibility of reaching this spatial resolution thus enabled us to measure the gaseous precursor consumption as a function of their residence time in the plasma.

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For release-liner preparation, coating stabilization of the silicone layer on base paper often requires pre- and post-treatment. In this study, we used atmospheric pressure diffuse coplanar surface barrier discharge in roll-to-roll configuration. The results of prepared coating showed that the A4 size clay-coated paper sprayed with silicone oil (0.25–0.50 mL) gradually decreased the tape peeling force (180°) with prolonged and repeated air plasma post-treatment. Best results showing increased hydrophobicity and significantly enhanced release factor of the coating were obtained after the plasma treatment in a nitrogen atmosphere. The silicone coating on the clay-coated paper reduced the reference release force from 5.5 N/cm to less than 1.5 N/cm after the repeated silicone spraying and short nitrogen plasma post-treatment. The results of X-ray photoelectron spectroscopy and scanning electron microscopy indicate silicone curing by plasma post-treatment and pore-closing of base paper without changes of the bulk material. The aging test lasting 3 months revealed the stability of the prepared coating.

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A dielectric barrier discharge in a corona process configuration is used to treat the surface of fluoropolymers in a nitrogen/organic precursor environment. The surface chemistry, thickness, and water contact angle of the deposited coatings are measured and used to build up an output matrix to be correlated with an input matrix built using electrical parameters of the discharge, the gas mixture chemical composition, and spectroscopic parameters measured in both the infrared and UV-Vis emission spectral regions. Partial least square regression (PLSR) model enables determining the most important plasma parameters to drive the coating physicochemical characteristics. From the PLSR model, it turns out that the plasma electrical parameters drive the surface modification process, at the expense of other plasma characteristics such as gas flow, gaseous precursor concentration, nitrogen vibrational temperature, and the level of gaseous precursor conversion within the plasma.