Fundamental Knowledge Thrust: Integratable Materials (IM)

Leader: Guo-Quan Lu, Virginia Tech

The goal of the IM thrust is to conduct long-term, high-risk materials research aimed at addressing the needs of four technological areas that are critical to integration of power electronics systems: thermal management; passive integration using multi-functional materials; electromagnetic fields sensing; and understanding physical failure mechanisms. The general technical approach is to explore synthesis, processing, and integration of nanoscale materials that have novel chemical, thermal, and electromagnetic properties. Since its establishment three years ago, the IM thrust has made significant progress in understanding physical mechanisms governing the processing of nanoscale particles and their applications for integration in power electronics systems. Major achievements resulted include: (1) a novel nanoscale metal pastes sintered at low temperature for attaching semiconductor devices – The sintered attachment offers superior electrical, thermal, and thermo-mechanical properties (Fig. 5). The new die-attach solution can also support devices capable of operating at junction temperatures over 500oC. The technology has been successfully transferred to a start-up company for electronic packaging of microelectronics, power electronics, and optoelectronics devices; (2) synthesis of a multi-ferroic nano-composite for making passive elements; the material system may be used as a platform for integrating passive elements; and (3) fundamental knowledge gained on competing physical processes between coagulation and coalescence aggregation of nano-particles, and its successful application in formulating nanoscale metal pastes for die attachment.

A lead-free die-attach solution using low-temperature sintering of nanoscale metal paste for high-performance and high-temperature interconnection of semiconductor devices.