Phosphating compositions and processes, particularly for use in fabrication of printed circuits utilizing organic resists

摘要

Composition and methods for providing a phosphate conversion coating on a metal surface, particularly a copper surface, characterized in that the phosphating composition includes at least one composition-soluble compound containing vanadium, niobium, tungsten or tantalum. The phosphate conversion coatings so produced are thicker, more durable and more uniform than those produced by known phosphating compositions. The compositions and processes are especially useful for providing a passivating/uniformizing coating layer on copper surfaces to which organic resin is thereafter deposited to serve as a resist in printed circuit fabrication sequences, particularly when the organic resin is an electrophoretically deposited organic resin. Also described is the microetching of copper surfaces with a phosphoric acid/peroxide microetchant preparatory to deposit thereon (or after a further provision of a phosphate conversion coating) of a photoresist which is then imagewise exposed and developed to provide a patterned resist.