DOUBLE SIDE ELECTRICAL INTERCONNECTION FLEXIBLE CIRCUIT BOARD

摘要

PROBLEM TO BE SOLVED: To obtain a flexible circuit board requiring no high cost deposition process nor repetitive laser boring process by providing a plurality of corresponding conductive vias at the positions on the surface of the flexible circuit where conductors are interconnected thereby minimizing specific tools required for designing the circuit. SOLUTION: The flexible circuit has a plurality of reliable conductive vias 201 for interconnecting conductors 208 on the first plane of a flexible dielectric film 205 with a plurality of solder ball contact pads 206 existing on the second plane of the conductors 208. From an inverted copper film segment 202 extending from a via 201, a unique offset is generated in the solder ball contact pad 206 and copper 203 to be plated fills the space between a copper film and a conductor on the first plane. The copper film segment 202 is fixed the second plane of the dielectric film 205 and the solder ball contact pad 206 is positioned. The recessed pads 201 are suitable for arranging the solder balls.