Ultrasonic Rivet Welding as Signal Technology in Power-Modules

Abstract:
As the automotive industry advances towards electric vehicles, the demand for high-performance power modules with increased power density and temperature operation is growing. Infineon's introduction of the HybridPACK(TM) Drive Generation 2 (HPD G2) addresses these needs by implementing advanced packaging technologies, including the transition from soldering to sintering and the innovative use of welded rivets. This abstract summarizes the development and advantages of the new rivet welding process for HPD G2, which replaces the traditional pin-rivet soldering approach that is incompatible with sintering. Using a structured methodology developed by Infineon, known as 6 steps and developed within funded research project “iREL 4.0”, the process is fine-tuned through statistical design of experiments to ensure robustness and reliability for production. The welded rivet technique not only offers manufacturing benefits like high design flexibility and improved positional accuracy but also provides a more resilient copper/copper connection suitable for high-temperature loads, thus ensuring the module's reliability even under the strain of increasing power densities. The successful implementation of this process highlights Infineon's ongoing commitment to innovation in the field of power module development for electric vehicles.