A method for enhancing the adhesion properties of polytetrafluoroethylene (PTFE) surfaces is presented. The approach employs a fast neutrals flow generated by a DC glow discharge plasma with a grid neutralizer. Low power levels (≈6 W) provided by the stable DC discharge prevent physical sputtering and surface damage, while strong UV radiation from pure argon promotes efficient defluorination. The choice of working gas composition, discharge parameters, and treatment duration was informed by plasma emission spectroscopy, water contact angle (WCA) measurements, and systematic optimization. The combined effect of low-energy neutral particles and UV radiation leads to a significant increase in surface energy to 82 mN/m and a reduction in WCA to 13°, confirming the effectiveness of the proposed method. Thanks to its simplicity, scalability, and reliability, the method holds significant potential for industrial applications.

Introduction. In view of the ever-tightening bandwidth requirements for wireless communication systems, the use of tunable or switching devices based on microwave keys is becoming increasingly popular. Currently, the development of microwave keys based on nonlinear materials, such as vanadium dioxide, is a relevant research direction. The keys based on this material are distinguished by a planar and simple design, thus being suitable for creating microwave devices using hybrid technology.Aim. To study the properties of thin vanadium dioxide films and to develop a microwave switch with electrical switching on their basis.Materials and methods. Experimental samples of thin vanadium dioxide films were obtained by magnetron sputtering. The phase transition parameters of the samples obtained experimentally were used in computer simulation of a planar two-electrode structure of a microwave key by the finite element method.Results. Experimental samples of vanadium dioxide films were manufactured, and the dependences of their resistivity on temperature were studied. The resistance of the obtained vanadium dioxide films was found to change threefold. A microwave key design based on vanadium dioxide films was developed. The formation of a currentconducting channel in vanadium dioxide films was simulated when a control voltage was applied. The threshold voltage of the element was estimated depending on its design parameters.Conclusion. The use of experimental data as a basis for computer simulation made it possible to determine the threshold values of currents depending on the topology and design of the proposed microwave key. The results of simulating the key structure showed the formed conductive channel to have clearly defined boundaries in terms of distribution of both current density and temperature across the film surface.

A fast-neutral flux generated from a glow gas discharge using a custom-designed source has been proposed to improve the adhesion of PTFE surfaces. The effects of glow discharge parameters and the composition of the working gas on the activation process were evaluated through contact angle measurements and subsequent surface energy calculations. PTFE surfaces treated in an argon atmosphere exhibited the most significant hydrophilic and adhesive properties, achieving a water contact angle as low as 13∘ and surface energy values of 82 mN/m, with an exceptionally high polar component. The optimal effect was observed when the optical spectrum of the plasma showed maximum intensity peaks in the UV range at wavelengths between 310 and 315 nm. The outcomes of this proposed method were then compared with those obtained using conventional industrial techniques for enhancing adhesion.