Abstract: Residual catalyst is removed from a dielectric substrate by exposing the substrate to a plasma formed from an inert gas.

Abstract: A method of making a printed circuit board is disclosed wherein metallic seed particles are applied to a surface of the substrate. An image of the desired conductor pattern is defined by a maskant layer to permit the subsequent electroless deposition of the conductor material upon the exposed seeded areas of the substrate. Then, the substrate surface is subjected to a plasma discharge to facilitate removal of the seed particles.

Abstract: A system for generating a substantially uniform plasma for processing a substrate having two major surfaces. Each of the substrate major surfaces may have electrically conductive portions. Two electrodes are oppositely disposed with respect to one another on either side of the substrate. A first r.f. power source is electrically connected to the first electrode and a second r.f. power source is electrically connected to the second electrode. The first and second r.f. power sources are out of phase with respect to one another, resulting in the generation of a substantially uniform plasma field.

Abstract: A procedure for cleaning drilled holes in laminated workpieces such as printed electric circuit boards includes the steps of coating a cutting instrument, such as a drill bit, with a liquid tracer prior to a cutting or drilling operation. During the cutting or drilling operation, the liquid tracer becomes mixed with material such as an electrically insulating binder layer disposed between opposed metal plates of the circuit board. Any smearing of the insulation material upon exposed metal surfaces of the drilled hole contain elements of chemical compounds used in the tracer. After extraction of the drill bit from the circuit board, the board is placed in a plasma reactor wherein the metal surfaces are etched to remove any smears and debris of the insulation material found on the exposed metal surfaces. The tracer elements, such as deuterium and phosphorus are monitored in the effluent plasma of the reactor to determine when the cleaning of drilled holes in the board is completed.