Macroscopic description of plasma polymerization

Industrial applications based on plasma polymerization require reliable processes that can be transferred to production-scale reactors. To enable an inexpensive access to control plasma deposition processes, macroscopic kinetics were investigated to describe plasma polymerization, which is based on the concept of chemical quasi-equilibrium. The evaluation of deposition rates was carried out in order to obtain the apparent activation energy for a specific process. Influencing factors, such as substrate temperature, energetic particles, reactor geometry, plasma expansion, pressure, monomer, carrier/reactive gas, power modulation, and plasma source were thoroughly examined. The obtained activation energy was correlated to the plasma-chemical processes, such as dissociation and radical formation, which are taking place within the active plasma zone. Since these processes are also contributing to the film growth, the activation energy was used for the scale-up of plasma polymerization processes.