Electromagnetic Compatibility (EMC) Shielding on Plastic Components by Electron-Beam Evaporation
(Room Room 104-B)
29 Apr 19
2:20 PM
-
2:40 PM
Tracks:
Protective, Tribological and Decorative Coatings
In recent years, there has been a growing demand for electromagnetic compatibility (EMC) shielding on plastic components. A particular challenge for the introduction of physical vapor deposition in this application is the low thermal stability of many engineering plastics in conjunction with the energy input of PVD processes. Furthermore, on most plastics a sufficient adhesion of PVD coatings directly on the substrate material still cannot be achieved, so that primers or lacquers have to be used as sublayers.
A new approach to PVD direct metallization is being pursued by Fraunhofer FEP. A short-cycle system for the coating of components by high-rate electron beam evaporation is used to coat components made of polycarbonate (PC) and PC/ABS (acrylonitrile butadiene styrene copolymer) blend. The pretreatment with an oxygen plasma is realized by a hollow cathode arc discharge within one minute. Primers are no longer required. Subsequently, the parts are coated with an aluminum layer of some microns thickness in less than one minute without showing thermal deformations or film delamination.
The key to meet these challenges lies in the intensive plasma pretreatment and the high evaporation rate already at low power input in combination with a substrate movement adapted to the component geometry.