Abstract: A process of manufacturing printed circuit boards which is useful in the formation of printed circuit boards containing both areas of thick conductive traces and areas of fine resolution conductors in a single conductive layer, and printed circuit boards formed from such a process. A conductive core is first fabricated containing areas of thick conductors on a relatively thin conductive base. The conductive core is then bonded to a sublayer such as “prepreg” with the thick conductive areas adjacent to the sublayer in order to form a relatively flat laminate. Proper bonding typically requires the use of high resin “prepreg” sublayer. In the alternative, an additional inner layer of pure resin can be inserted between the conductive core and the insulating sublayer prior to bonding. After bonding, the conductive surface of the laminate is formed into printed conductor traces by methods known in the art.

Abstract: A method is described for the manufacture of a Copper-Aluminium-Copper component (C-A-C “sandwich”) which can be used in the production of multilayer printed circuit boards, obtained by means of joining two external sheets of copper to one internal sheet of aluminium by means of a process of electro-mechanical joining, which does not require the use of additional material (such as, for example, an adhesive) and guarantees a consistently high level of quality. The joining process, normally continuous, is based on the use of a sonotrode to effect ultrasonic welding, wherein a single ultrasonic weld provides two joining zones between the two external copper sheets and the one internal aluminium sheet. According to a further embodiment, the component is manufactured with at least one layer of resin deposited externally on one of the external faces of the two copper sheets, which are not into contact with the internal aluminium sheet.

Abstract: A process of manufacturing printed circuit boards which is useful in the formation of printed circuit boards containing both areas of thick conductive traces and areas of fine resolution conductors in a single conductive layer, and printed circuit boards formed from such a process. A conductive core is first fabricated containing areas of thick conductors on a relatively thin conductive base. The conductive core is then bonded to a sublayer such as “prepreg” with the thick conductive areas adjacent to the sublayer in order to form a relatively flat laminate. Proper bonding typically requires the use of high resin “prepreg” sublayer. In the alternative, an additional inner layer of pure resin cab be inserted between the conductive core and the insulating sublayer prior to bonding. After bonding, the conductive surface of the laminate is formed into printed conductor traces by methods known in the art.