Patent ID: 6035527
Filing Date: 2000-03-14
Classification: H01K,H05K,Y10T

Abstract:
A method for the production of printed circuit boards, the method comprising the steps of;a) Removing material from a substrate to form a first recess in a first side of said substrate, said first recess having a bottom and a side surface, said first recess side surface defining a first recess width, said first recess for generating a first line of a circuit pattern;b) removing material from said substrate to form a second recess in a second side of said substrate, across from and aligned with said first recess, said second recess having a bottom and a side surface, said second recess side surface defining a second recess width, said second recess for generating a second line of a circuit pattern;c) removing material from said substrate to form, in one of said first and said second sides, a third recess having a bottom and a side surface, said third recess for generating a third line of a circuit pattern;d) removing material from said substrate to produce a through hole centered in and connecting said first recess and said second recess, said through hole having an inner surface defining a width less than said first recess width and less than said second recess width;e) covering said first, second and third recess side and bottom surfaces and said through hole inner surface with a base layer;f) selectively removing said base layer deposited in step e) from said first, second and third recess side surfaces while leaving said base layer on said first, second, and third recess bottom surfaces and on said through hole inner surface; andg) applying a conductive material, following step f), to cover said base layer and to cover said first, second, and third recess side surfaces, wherein said base layer is at least one of catalytic and activating relative to said conductive material.