Surface Preparation of Polytetrafluoroethylene Additive Copper Plating Adhesion
Original Publication Date: 1989-Nov-01
Included in the Prior Art Database: 2005-Jan-29
The average peel force of copper lines to polytetrafluoroethylene (PTFE) films can be increased from essentially zero to a value greater than the cohesive strength of the fluoropolymer by a combination of surface preparations. The method involves roughening the surface of the fluoropolymer laminate to provide a mechanical bond for the overlying metal seed layer. This seed layer yields a surface which mechanically links the plated copper lines to the top of the roughened polytetrafluoroethylene. If the surface is not roughened before application of the seed layer, peel force measurements cannot be effected, since the plated copper layer falls from the laminate before removal from the copper bath.