In a pulsed plasma process for surface treatment of a substrate the containing reactor vessel (11) has an inner cross-section conforming to the substrate geometry so as to confine the intense plasma region to the substrate surface (12). Preferably this region should be within 15 to 20 mm of the surface....http://www.google.com.au/patents/US4749589?utm_source=gb-gplus-sharePatent US4749589 - Method of surface treatment
