Low temperature cofired multilayer ceramics (LTCC), was developed for the production of highly complex electronic equipment and introduced into automotive, telecom and electro-medical applications. In conjunction with LTCC the direct mounting of unpackaged semiconductors in Flip-Chip (FC) technology where chips are glued or soldered top down on to ceramic carriers seems to be advantageous. Both technologies together were applied in power electronic applications for wattages of up to 150 W. By increasing the switching frequency of the converters by a factor of 50 the decrease of the values and sizes of capacitors and chokes can occur to such an extent that they can be integrated into the carrier as embedded components. Especially adequate planar ferrite chokes can be designed.
Within the AMFAS project LTCC & MCM, used in automotive and telecom equipment successfully, was investigated, adapted and tested for application in power electronics (SMPS, step down convertors, electronic ballasts). The advantage to integrate passive discrete components into the ceramic carrier was taken consistently. The semiconductors required and the adequate assembly technic were also investigated.
Furthermore topologies for harmonic filters and control circuits together with the respective IC-technology and power transistors were investigated. Prototypes of switching converters were assembled to demonstrate the technical feasibility and the reliability of the technique proposed. After the definition of an optimal production process and the evaluation of the cost of the production equipment the economy of the proposed technology for power electronic products were demonstrated for various but large production volumes.
It was expected that the proposed technology which requires specific knowledge, equipment and specially trained staff will increase dramatically the competitiveness of the companies involved in the project in comparison with their - often Non-European - competitors applying conventional printed circuit board technology which is easy to copy and easy to install with a reasonable amount of invest.