Ing. Norbert Koster
- System design
Cleaning is becoming more and more of importance in the modern world. Special applications require cleanliness levels that cannot be achieved by 'old fashioned' cleaning methods and novel techniques are required. One of these techniques is plasma cleaning.
Plasma cleaning can be used to remove the last layer of contaminants from a surface to make it molecular clean. The plasma process developed by TNO has the special feature that most of the cleaning action is done by chemical reactions and not by physical sputtering of the surface. Shielded Microwave Induced Remote Plasma (SMIRP) is extremely gentle to surfaces, in contrast with conventional plasma cleaning methods which rely more on physical sputtering and high cleaning rates. This technique is especially suited for delicate surfaces, thin layers, electronics and heat sensitive objects.
Plasma's are also widely used to sterilize objects. The great benefit of this is that the plasma not only sterilizes or disinfects, but it also removes the potentially poisonous remains by the cleaning action. The great disadvantage of plasma sterilization up to now was the lack of a method to package the objects before sterilization to prevent contamination after the sterilization process has ended.
TNO has developed a method called Plasma In a Bag (PIB), which enables sterilization of an object inside a sealed bag. When the sterilization process is completed, it is no longer necessary to handle the object itself because of the packaging already applied. It is now also possible to re-sterilize the object without breaking the sealed envelope, for instance after a long period on the shelf.