Processes for preparing a non-conductive substrate for electroplating

A method for electroplating a conductive metal layer onto a substrate including a conductive metallic surface and at least one non-conductive through hole surface, said method comprising, the steps of:

• A. providing a liquid dispersion of carbon comprising from about 0.1 to about 20% by weight electrically conductive carbon having a mean particle size within the range from about 0.05 to about 50 microns;
• from about 0.01 to about 10% by weight of a water dispersible binding agent for binding to said carbon particles;
• and an aqueous dispersing medium;
• B. applying said liquid dispersion to the conductive metallic surface and to the non-conductive through hole surfrace, forming a coating thereon;
• C. separating substantially all of the aqueous dispersing medium from the carbon of said coating, whereby said carbon is deposited on the non-conductive through hole surface in a substantially continuous layer, and said carbon is also deposited on the conductive metallic surface;
• D. after said separating step, microetching the conductive metallic surface and the non-conductive through hole surface, thereby removing substantially all of said carbon from the conductive metallic surface while leaving a substantially continuous layer of said carbon on the non-conductive through hole surface;
• and
• E. electroplating a substantially continuous metal layer over said carbon deposited on said non-conductive through hole surface.