Abstract:
A method of increasing adhesion between a copper or copper alloy layer and a polymeric resin. The method includes the steps of a) applying a pre-dip composition to the copper layer; b) applying a nano-oxide composition to the treated copper layer, c) applying a post-dip composition to the nano-oxide treated surface, and d) bonding a resin to the treated copper surface. The nano-oxide composition comprises (i) a chlorite; (ii) a caustic; (iii) a phosphate salt; (iv) an organic nitro compound; and (v) a thio compound, The post-dip composition is an alkaline solution that comprises (i) a phosphate salt; (ii) a source of molybdenum ions; and (iii) a thiazole. The process of the invention is useful for improving the bond between copper and a resin, including high Tg resins, halogen-free resins, and high speed/lost resins.
Abstract:
An aqueous treatment solution for increasing the cleaning capability of a treated copper surface comprising: a) an organic compound selected from the group consisting of organic acids, alcohols, ketone, nitriles and combinations of one or more of the foregoing; and b) an oxidizing agent. The aqueous treatment solution is usable in a process for metallizing the walls of holes within a printed wiring board substrate having metallic and non-metallic regions, wherein the printed wiring board is treated with a reducing agent and then contacted with an aqueous dispersion of carbonaceous particles to form a coating of the dispersion over the substrate. The process comprises the step of contacting the metallic regions of the printed wiring board substrate with the aqueous treatment solution to remove deposited carbonaceous particles therefrom. The aqueous treatment solution provides a clean copper surface while providing a low microetch rate.
Abstract:
An aqueous tarnish inhibiting solution comprising a mercapto carboxylic acid find a corrosion inhibitor to produce an anti-tarnish layer on metal surfaces, such as silver plated copper leadframes and a method of using the same is pro vided. The composition provides an improved anti-tamish layer that does not affect wirebondability or the adhesion of a mold compound to a leadfrarne.