METHOD FOR SHORTENING INITIATION TIME FOR ELECTROLESS BATH

摘要

PROBLEM TO BE SOLVED: To generate catalytic islands around a small granular metal oxide and to form a sufficient quantity of solid copper thereon by a method, wherein a conductor, a via or a pad exposes a resin and a small granular metal oxide on the surface thereof at a required part, before a circuit board is immersed into a reducing solution. ;SOLUTION: A two derivative continuous processing board is reduced for 5 min in a solution of 1.0 mol. hydrogenated boron and 0.25 mol. EDTA. The substrate is then cleaned with deionized water and immersed into ion palladium solution for 10 seconds. Subsequently, it is cleaned with deionized water and left as it is for 2 minutes in an electroless bath. According to the method, the deriving time is shortened, while increasing the density at the bonding part and the size of copper particle plating the conductors, pads and vias on a circuit board can be reduced.;COPYRIGHT: (C)1996,JPO