Miniature circuitry and inductor components in which multiple levels of printed circuitry are formed on each side of a support panel, typically a printed circuit board or rigid flex. Magnetic members are embedded in one or more cavities in said support panel. Electrical connection between the plural levels of circuitry and multiple windings around the magnetic members are provided by plural plated through hole conductors. Small through hole openings accommodate a plurality of the plated through hole conductors since each is insulated from the others by a very thin layer of vacuum deposited organic layer such as parylene having a high dielectric strength. Adhesion of this plated copper to the organic layer is provided by first applying an adhesive promotor to the surface of the organic layer followed by the vacuum deposition of the organic layer.