Verfahren zur Herstellung von mehrlagigen starr-flexiblen Leiterplatten

摘要

A method for producing a hybrid multi-layered circuit substrate which utilizes prefabricated flexible printed circuit(s) which are rigidized in areas which define high density hybrid circuits. The hybrid circuit regions are formed by disposing copper-lined sheets on both surfaces of the flexible circuit, adhesively bonding the copper-lined sheets to the flexible circuit, forming through-hole conductors and etching a circuit pattern in the copper layer of the lined sheets. The copper-lined sheets are initially general coextensive in size and shape with the flexible circuit and are subsequently severed so that the copper-lined sheets remain only in the hybridized portions of the product. Separation is achieved by mechanically punching along predetermined boundaries and is facilitated by providing either any elongated narrow through-hole at the boundary of the hybrid circuit from which the flexible circuit will extend the end product or by forming a groove in the copper-lined sheets at such boundary.