MULTILAYER PRINTED CIRCUIT BOARD AND METHOD OF MANUFACTURE

The multilayer printed-circuit board has a metallic substrate (1) with holes (12), the surface of the substrate (1) and the walls of the holes (12) being covered with an insulation layer (9) which is produced by successive application and mechanical treatment on two sides of a coating from a powdered epoxy resin composition. The insulating-material coating (2) produces an insulation relief (16) consisting of a photosensitive composition, the relief being filled with metal by vacuum deposition. Removing the metal from the projecting parts of the relief (16) produces conductors (4) and contact surfaces (5) of a conductive pattern layer (5). An insulation relief (18) is then formed which corresponds to the arrangement of contact surfaces (11) and connection bumps (10) which connect the conductor pattern layers (3, 6), and the relief is covered with a metal layer. After the metal has been removed from the projecting parts, an insulation layer (9) is obtained in which the connection bumps (10) and the contact surfaces (11) are located. Additionally, an insulation relief (19) is formed which corresponds to the configuration of a conductor pattern layer (6), the metal is applied and is worked mechanically, so as to produce the conductors (7) with contact surfaces (8) of the conductor pattern layer (6).