Abstract: A method of improving the adhesion between a synthetic substrate and metallized layers deposited thereon. A glass resin layer is spin-coated onto an epoxide substrate. The glass layer is covered by a photoresist layer which is roughened by reactive ion etching. The roughened contour of the photoresist layer is transferred via reactive ion etching to form a perforation pattern in the glass layer. The substrate is then etched vertically and horizontally to produce recesses in the substrate having overhanging walls. A thin copper layer is sputtered onto the substrate and copper conductors are sputtered onto the thin copper layer, the copper layers filling the recesses. The recesses and overhangs form mortices in the substrate, and the copper layers within the recess form tenons which fittingly engage with the mortices to produce adhesion between the substrate and the metallized layers in the order of 1000 n/m.

Abstract: A method of improving the adhesion between a synthetic substrate and metallized layers deposited thereon. A glass resin layer is spin-coated onto an epoxide substrate. The glass layer is covered by a photoresist layer which is roughened by reactive ion etching. The roughened contour of the photoresist layer is transferred via reactive ion etching to form a perforation pattern in the glass layer. The substrate is then etched vertically and horizontally to produce recesses in the substrate having overhanging walls. A thin copper layer is sputtered onto the substrate and copper conductors are sputtered onto the thin copper layer, the copper layers filling the recesses. The recesses and overhangs form mortices in the substrate, and the copper layers within the recess form tenons which fittingly engage with the mortices to produce adhesion between the substrate and the metallized layers in the order of 1000 n/m.

Abstract: A process for producing printed circuit boards having metallic conductor structures embedded in the insulating substrate and whose front and back sides are conductively connected by means of plated through holes. The first steps of the process comprise producing a matrix on an epoxy resin substrate consisting of a lift-off layer, an aluminum barrier layer and a positive photoresist layer. A negative image of the desired conductor pattern is then generated in the photoresist layer using conventional photolithographic techniques. The negative image is etched into the barrier layer and the lift-off layer such that an undercut occurs under the barrier layer. Subsequently, vertical trenches are etched into the epoxy resin substrate. After drilling of the through holes, an activating layer of copper is deposited by means of magnetic field enhanced cathode sputtering on the surfaces of the trenches, the through holes and the barrier layer.

Abstract: A method of making printed circuits, where on both sides sacrificial foils are laminated onto a synthetic resin prepreg. Through-holes are drilled. The copper foil is subsequently etched off. A negative photoresist foil is laminated on the prepreg surface roughened by etched-off copper dendrites. The foil is exposed and developed in accordance with the respective conductive pattern. Subsequently, copper is sputtered onto the surface of the photoresist, the surface and the bottom of the photoresist channels defining the conductors, and onto the surface of the drilled holes by means of magnetron-enhanced cathode sputtering. The copper sputtered onto the surface of the photoresist is removed by means of a scrubbing roller. Then, copper is deposited in accordance with the additive process on the copper sputtered in the photoresist channels and the drilled holes. After the stripping of the photoresist, the printed circuit is completed.

Abstract: substrates with oxidized surfaces, as e.g. SiO.sub.2 layers on silicon semiconductors and aluminum surfaces, are wetted with an organic silicon compound, for example, .gamma.-aminopropyltriethoxysilane dissolved in an organic solvent such as trichlorotrifluoro ethane. The solvent is then removed in a dry atmosphere. The evaporation step can be carried out by suspending the substrate in volvent vapor over a supply of refluxing solvent while cooling the solvent vapor such that fresh, dry solvent vapor continuously passes along the substrate and absorbs traces of moisture. Subsequently, a coating is applied from a solution of a polyamido carbon acid formed of pyromellitic acid anhydride and an aromatic amino component and the polyamido carbon acid is heated to form an adherent layer of polyimide.