In times of climate change and increases in energy use, the demands of power modules for the efficient and reliable control of electric motors continue to rise. Modern module concepts are reaching their limits in terms of power density, current carrying capacity, and reliability to increase lifetime and reduce costs. A critical area for improving power modules is the material system used in them, as well as their electrical and thermal interconnection.
The Die Top System (DTS®), jointly developed by Heraeus and Danfoss, offers a performance improvement by enabling copper wire bonding of the substrate. DTS® is custom designed for the specific substrate layout and consists of a 50 µm thin copper plate with pre-applied sinter paste. The innovative system of copper wires, DTS® and sintered connection to the substrate replaces traditional materials such as aluminum bonding wires and solder pastes. This is a revolutionary step in the assembly and connection technology of power modules.
By harmonizing the materials, the electrical and thermal conductivity as well as the reliability of the die-connection is greatly improved, and the module performance is increased by 30 percent. This gives automotive manufacturers more freedom in terms of design, as they can achieve the same performance with smaller modules and less installation space is required. The system is used by Heraeus’ customer Danfoss in the power modules they manufacture as "Danfoss Bond Buffer" (DBB). Other customers are already waiting in the wings to use DTS® in series production.