Heraeus Electronics introduced a new system for chip-top contacting in power electronics modules at the PCIM Asia conference in Shanghai. The Die Top System boosts the chip’s current-carrying capacity by more than 50% and offers significantly greater reliability, which allows manufacturers of electric vehicles and hybrid cars to test the limits of power transmission in simulation tests – a crucial factor in the competition for China’s e-mobility market.
China is setting the standard for the further development of e-mobility. A significant driver in the Chinese market is the quota system for electric vehicles established by the Chinese government:
Automobile manufacturers are now required to produce a fixed quota of electric vehicles and plug-in hybrids. Starting in 2019, both domestic and foreign carmakers who fail to meet minimum targets for the proportion of alternative drives manufactured and sold will face sanctions.
Proof of high electrical and thermal reliability is possible
In light of this requirement, the topic of power electronics is becoming increasingly important for e-mobility manufacturers.
Heraeus Electronics presented the Die Top System at the PCIM Asia conference in Shanghai. Developed from Danfoss Bond Buffer technology, the system offers new assembly and joining technology for silicon (Si) or wide-bandgap semiconductors.
“The Die Top System developed with Danfoss is particularly well suited for applications that demand high reliability,” explains Klemens Brunner, head of the Heraeus Electronics global business unit. To enable the reliability of the Die Top System to be tested upfront, Heraeus Electronics is the only company in China to offer a new engineering service, the Power Cycling Test, from now onwards. This means that customers can see on site if the Die Top System meets their specific needs.
“Manufacturers of electric and hybrid vehicles can benefit from these advantages, which allow them to test the reliability of the Die Top System for their purposes and to explore the limits of power transmission in a power cycling test on site in China,” explains Klemens Brunner regarding the particular use of this new engineering service for users.
Greater current carrying capacity and power cycling capability
With its new design, the Die Top System not only increases the power module’s current carrying capability, it also boosts its power cycling capability. This makes it possible to have junction temperatures of up to 200⁰C. A highly conductive copper foil is applied to the semiconductor chip using a sinter paste. This distributes the current evenly across the semiconductor chip, reducing heat and better avoiding hot spots in the semiconductor. The foil also strengthens the chip during production for the power module. As a result, more efficient copper bonding wires can be used in place of traditional aluminum bonding wires. This makes it possible to achieve more power with the same module size or equivalent power with smaller modules.