Flexible Circuit Carrier with Integrated Passives for High Density Integration

摘要

High density interconnect and wafer level packaging technologies are exceedingly challenged by the compactness of autarkic distributed microsystems. The realization of extremely space saving system-level integration requires technologies allowing 3D packaging while taking into account the required space of passive components which are important parts of such systems. The minimization of the area needed for passive components such as coils, resistors, capacitors and filters is an important factor for volume reduction of such systems. The application of thin flexible circuit carriers stacked by bump pad connections is a possibility to realize the 3D integration. Flexible circuit carriers based on polyimide dielectrics with high density copper wiring systems and passive components are produced at wafer level using thin film processes. The units are diced by sawing and released from the carrier wafer by dissolving a release layer which was chosen as first layer of the thin film build up. Layout and design of the technology demonstrator with passive components as well as the technological process flow are described in detail and first results of the integration of resistors, coils, capacitors and filters in flexible circuit carriers are discussed.