Inducted May 2013
Charles Ducas was an American inventor and the first to describe etching and plated up conductors, as well as the precursors to multilayer circuit boards. In 1925, Ducas submitted a patent application for a method of creating an electrical path directly on an insulated surface by printing through a stencil with electrically conductive inks. This method is credited as the source of the term "printed wiring" or "printed circuit." In the patent, Ducas conceived forming grooves in a dielectric and filling them with conductive paste, then electroplating the paste. Conductive paste could also be printed, or stenciled onto dielectric and then electroplated. Both sides of the dielectric layer could be used for circuitry. Ducus made mention of the future of multilayer boards, stating: “Two or more panels may be positioned adjacent to each other... .” In another application, Ducas described electroplating a copper, silver or gold pattern onto a low temperature metal alloy through a contact mask, with heating applied to separate the conductor from the fusible bus plate and mask.