Micro-structured electrode arrays:high-frequency discharges at atmospheric pressure—characterization and new applications

Micro-structured electrode (MSE) arrays allow to generate large-area uniform glow discharges over a wide pressure range up to atmospheric pressure. The electrode dimensions in the µm-range realized by means of modern micro-machining and galvanic techniques are small enough to generate sufficiently high electric field strengths to ignite gas discharges applying only moderate radio frequency (RF, 13.56 MHz) voltages (80–390V in Ne, He, Ar and N2). The non-thermal plasma system is characterized by a special probe measuring the electric parameters. The MSE-driven plasmas show a different behavior from conventional discharge plasmas depending on the pressure and the type of gas. With the MSE arrays as plasma sources, several applications were developed and successfully tested: Plasma chemistry (decomposition of waste gases like CF4) and thin film deposition (e.g. SiO2 layers on various substrates). A new atmospheric pressure application realized in our lab is the sterilization of food packaging materials