Berlin 2005 – scientific programme

Parts | Days | Selection | Search | Downloads | Help

P: Plasmaphysik

P 8: Niedertemperaturplasmen / Plasmatechnologie 4

P 8.3: Talk

Saturday, March 5, 2005, 09:15–09:30, HU 3038

Non-thermal plasma as sterilisation and coating technique — •Christian Schrader and Karl-Heinz Gericke — Institut für Physikalische und Theoretische Chemie, Technische Universität Braunschweig, Hans-Sommer-Str. 10, D-38106 Braunschweig

Non-thermal plasma processing techniques have been established for a wide range of applications. Micro structured electrode (MSE) arrays consist of an interlocked comb like electrode system with µm-gap widths. The electrode dimensions in the µm-range are realized by photolithography and galvanic techniques. These arrays are capable to generate large area uniform glow discharges up to atmospheric pressure. The discharge phenomenon is described with the DC breakdown theory leading to an interest in RF frequency dependent breakdown mechanisms. One of the applications is the synergetic sterilisation of method referenced spores and the additional deposition of diffusion inhibiting layers like SiO₂ on food packaging materials. We successfully sterilised 10⁶ spores of the bacterium B. cereus at 1000 mbar in Helium and the same quantity of spores of the fungus A. niger in Ar. We approved the deposited SiO₂-layers on several polymers with ATR-IR-spectroscopy. The UV and VUV participation of the sterilisation result is discussed in further detail. Finally the non-thermal plasma characteristics of the application setup are presented with voltage-current pathways leading to a normal glow discharge combined with UV-VIS optical emission characteristics.