3D modular power electronic systems, based on embedded components

Today's power electronics modules typically consist of a ceramics substrate (DCB - Direct Copper Bond), carrying IGBTs, diodes or MOSFETs. These semiconductors are soldered or sintered to the ceramics and their top sides are interconnected by thick Al wires. An integration of further components or functions on the DCB substrate is difficult or even not possible. Therefore, driver circuits and controllers have to be mounted to a separate substrate, typically an organic Printed Circuit Board (PCB). The PCB has to be connected to the DCB by wires or pins. The mechanical integration of the whole system requires a bulky housing, often made of die cast Al. In the last years, the capability of PCB embedding technology for the realization of low and high voltage power modules was demonstrated. Fraunhofer IZM together with partners from the industry demonstrated the feasibility of an automotive inverter with 600 V and 50 kW switching power, containing 18 embedded Si IGBTs and diodes. Another 600 V module demonstrated the capability of embedded SiC chips for very fast switching modules with extremely low parasitic effects. Both modules were planar and further SMC components could be assembled on top. A large variety of embedded power electronic modules has been realized so far. Size and performance of the systems differ accordingly. They range from modules with lateral dimensions of a few square millimeters having a few components embedded for low voltage and currents of up to 50 Amperes, to complex assemblies with 24+ embedded semiconductors and a module area of several square decimeters for an operating Voltage of 600 V and a total power of 150 k W. The present paper will give an overview of different developments and results in power electronic embedding using PCB technologies. A variety of results from recent projects dealing with embedded power modules will be presented. To address the integration of the required driver circuits and controllers, the idea of modularization of such electronics systems will be presented. Here already packaged components will be used and embedded into PCB layers too. As a result, a modular approach to form a complete system will be developed. Different functional layers, e.g., power switches, logic modules, will be formed and finally stacked und connected to form the system. The concept for a 3D modular power electronic system will be introduced.