High frequency switching and high temperatures cause conductive connections in power electronics to age quickly. One solution to this problem involves temperature-resistant materials such as SiC substrates and silver pastes. The high melting point of silver, however, prohibits the use of a melting process to produce the conductive connection, because the electrical components would not survive the high temperatures.
The solution: With silver sintering, silver particles can be shaped to form stable connections without melting. The ASM SilverSAM (which stands for Silver Sintering Automated Machine) is the automated solution for this process. It can be easily combined with other ASM solutions for paste printing, die-attach and encapsulation. With the efficient ASM SilverSAM, component manufacturers can produce more durable power modules with improved electrical and thermal properties.
Focus on automotive e-mobility
Machines for applications in automotive power electronics are one of ASMPT’s major focus areas. Find out more in the article.
While the electrification of mobility gains momentum, sintering is becoming a key technology to address topics such as durability, power density and cost of power modules. ASM's dedicated process solutions are enabling the development and production of next generation power modules.
The paste with silver particles is first applied to the DBC (direct-bond copper), AMB (active metal braizing) or any other substrate with a DEK printer (Ag paste application). This is followed by the pre-sintering or tacking process, which require higher bonding forces as well as bonding heads for temperatures of 100°C (212°F) or more to firmly connect the die to the substrate and keep it from shifting.
The core sintering process uses pressure, heat and time in material-specific combinations to permanently join the silver particles in the paste at temperatures that are far below the silver’s melting point. The ASM SilverSAM combines flexibility, productivity and quality of the sintered materials within one platform.
The innovative tooling in the ASM SilverSAM ensures an oxidation free sintering environment for handling copper materials in a vacuum or in a protective atmosphere (N2, HCOOH etc.). Furthermore, the tooling can be configured to exert pressure only to the desired surfaces (dies, chips, copper plates etc.) and keep cavities or grooves on the substrate untouched. A special film between the die and the tooling protects the components.
The ASM tooling can handle all common substarte formats such as Master Card Panel, singulated DBC/AMB, leadframes or even heatsinks and wafers. The platform is configurable from one to three presses in a single ASM SilverSAM so that labs and prototype shops can be equipped with the smallest semi-automatic version, while high-volume factories can use the fully automated ASM SilverSAM version which is expandable with multiple presses for optimized throughput and productivity.
Back Side Die Metallization - High throughput sputtering solution for thick and thin films and multiple wafer sizes.
Multi-beam laser dicing of SiC wafers at extremely low thermal impact while having a very high productivity.
Extremely powerful, modular and flexibly configurable solution for use in advanced-packaging processes.
A scalable equipment platform to go from R&D to high volume production with multiple presses.
Automatic Encapsulation Solution for Power Module and Double-Sided-Cooling (DSC) packages.
If you need further information, please do not hesitate to contact us! The ASM team looks forward to answering your questions.