Abstract: The invention is for the formation of multilayer circuit boards where layers are formed sequentially using selective plating techniques and imaging of dielectric materials to achieve fine line resolution and interconnections between circuits. The invention permits the sequential formation of multilayers of higher density using imaging techniques.

Abstract: The invention is for the formation of multilayer circuit boards where layers are formed sequentially using selective plating techniques and imaging of dielectric materials to achieve fine line resolution and interconnections between circuits. The invention permits the sequential formation of multilayers of higher density using imaging techniques.

Abstract: This invention relates to electroless metal deposition and more specifically, to a process where a plating solution is brought to equilibrium and thereafter operated with the concentration of plating reactants and by-products maintained substantially constant. The plating solution treated in accordance with the invention is one having evaporative losses of at least one percent per plating cycle. Following the process, a plating solution can be operated indefinitely and yields a metal plate of uniform quality and predictable properties at any time during use of the solution. The invention avoids the known problems of by-product build-up and variable concentration of reactants typically associated with the use of such solutions.