Evaluation of enhanced power modules with planar interconnection technology for aerospace application

Abstract:
The intentions of the More Electrical Aircraft (MEA) concept are weight reduction and higher efficiency. The main topic here is the application of electrical systems instead of conventional hydraulical, pneumatical and mechanical systems. Some of these systems require a liquid cooling, which results in additional weight for pipes and heat exchanger. The total weight of cooling loop can be optimized by increasing the absolute inlet temperature and the difference between inlet and outlet temperature. Subsequently, the power modules must be designed for a higher temperature by integrating more chip area or by reducing the thermal resistance from chip to cooling liquid. A lower thermal resistance can be achieved by the planar inter-connection technology SiPLIT(c). Further advantages of this approach are a lower parasitic inductance, higher surge current capability and higher lifetime due to the use of copper interconnects instead of bond wires. Aluminium thick wire bonds are still the limiting factor for the electrical performance and lifetime of power modules. This paper presents the evaluation of SiPLIT(c) technology by direct comparison with a standard module. All parameters such as chip types, layout, substrate, baseplate and module pins are identical. The only difference is the interconnection technique between chips and chips to module pins.