Electron density determination for plasma assisted sterilization processes

An effective measurement concept for the precise determination of the electron density in plasma assisted sterilization processes is presented in this paper. Here, plasmas offer a promising approach for heat or chemical sensitive materials, like surgery instruments. Therefore, the Multipole Resonance Probe (MRP) is investigated over a wide frequency range. Based on the evaluation of an unambiguous resonance behaviour, the resonance frequency can be determined from 0.5 to 6 GHz. Proven in 3D electromagnetic field simulations and measurements in an excited Argon plasma, the additional center of gravity method increases the performance and the MRP can be used for an evaluation of a wide density range. Hence, the density can be controlled effectively and used in a feedback control loop.