Patent ID: 7402254

Claim:
A method for forming a core member for use in laminating to another core member to form a printed wiring board, comprising: forming a first copper coating on a first side of a dielectric substrate, wherein the dielectric substrate is glass reinforced; forming a second copper coating on a second side of the dielectric substrate, wherein the first and second sides are located on opposite sides of the dielectric substrate; forming first and second holes, wherein each of the first and second holes extends through all three of the first copper coating, the dielectric substrate, and the second copper coating; plating the first and second holes with a conductive metal to form a conductive path in each of the first and second holes between the first and second copper coatings, wherein the plating is performed using one of electroless or electrolytic plating; filling the entirety of each of the first and second holes with a conductive adhesive by one of screening, stenciling, flood coating, doctor blading, immersing and injecting, wherein the conductive adhesive is heated to enhance its flow characteristics; heating the conductive adhesive to about 130 degrees Celsius until the degree of cure of the conductive adhesive is advanced from about 20% to about 80% of complete cure; removing a first sub-portion of the first and second copper coatings so that the conductive adhesive in the first and second holes extends beyond an entirety of a second sub-portion of the first and second copper coatings on both sides of the dielectric substrate in a direction away from the dielectric substrate, wherein the conductive adhesive in the first and second holes extends beyond the entirety of the second sub-portion of the first and second copper coatings to form first and second nubs of the conductive adhesive; removing the second sub-portion of the first and second copper coatings from the entirety of both the first and second sides of the dielectric substrate except for in a region between the first and second holes on one of the first or the second sides of the dielectric substrate using a photolithographic process with a positive or negative photoresist, wherein the remaining second sub-portion of the first or second copper coatings connects the conductive adhesive in the first and second holes together.