Patent ID: 6823585
Filing Date: 2004-11-30
Classification: H05K,Y10T

Abstract:
A method to form surface plating metallization on a substrate comprising the steps of:providing a substrate having a top surface and a bottom surface and a plurality of conductive vias providing electrical connections between said top and bottom surface and between top surface vias; applying a first layer of tape on said top surface; applying a second layer of tape on said first layer of tape; creating a first path through both said first layer of tape and said second layer of tape to expose a portion of said top surface, said first path contacting at least one conductive via on said top surface; creating a second path through said second layer of tape to expose a portion of said first layer of tape and intersecting with said first path wherein said second path is connected from said first path to an edge of the substrate; depositing a seed layer over the surface of said second layer of tape to create a seeded plating path in said first path and a sacrificial seeded conduction path in said second path intersecting with the seeded plating path; removing said second layer of tape while maintaining a seeded plating path in said first path and a sacrificial seeded conduction path on the surface of said first layer of tape; connecting said sacrificial seeded conduction path to a plating potential at the edge of the substrate; immersing said substrate in a plating solution and applying current through the sacrificial seeded conduction path to plate the seeded plating path; and removing said first layer of tape to remove the sacrificial seeded conduction path and uncovering a selectively plated substrate surface.