Monitoring electroless plating.

摘要

Apparatus and method for determining the initiation, progress, and quality of electroless plating of blind or through-hole walls in circuit panels. A test coupon (10) for monitoring the plating is provided having a sensitized initiation conductivity zone (23) and sensitized through-hole (13) walls arranged in a series resistance circuit (12, 14, 15, 16). Both conductivity zone and series circuit are measured periodically as to resistivity to determine the start of electroless plating and its progress during continued immersion of the panels in the plating bath.