ASSESSING MICRO-VIA FORMATION IN A PCB SUBSTRATE MANUFACTURING PROCESS

摘要

Embodiments of the invention include methods and systems of assessing micro-via formation in a substrate manufacturing process. In one embodiment of the invention, a microvia opening is drilled through a top dielectric layer of a multilayer printed circuit board (PCB) substrate, the multilayer PCB substrate including the microvia opening is desmeared down to a capture pad in a conductive layer; a sequential electrochemical reduction analysis is performed over the capture pad within the microvia opening to determine if there is any existing contamination in the bottom of the microvia opening. If a contaminant is found, production is put on hold and appropriate actions are taken to understand the source of contamination. Without any contamination, the microvias along with the remaining circuitry of the PCB substrate may be plated with a seed layer of Electroless plating followed by electrolytic plating.