Effect of Processing Condition on Reliability Performance of SiC Package by Pressure-less Silver Sintering

Inhalt:
The rapid development of wide-bandgap semiconductors, particularly silicon carbide (SiC), has driven the demand for high-performance die-attach materials in power electronics. Traditional solder materials with limited thermal conductivity fall short under high-power conditions. This study evaluates the effectiveness of pressure-less Ag sintering pastes as an advanced die-attach solution for SiC MOSFETs on bare copper substrates. Three types of pressure-less silver-based materials were compared to conventional solder paste in a TO-247-4L package. The sintered silver layers demonstrated superior thermal conductivity, significantly lower electrical resistivity (<0.008 mOmega·cm), and lower processing temperatures than solder. Morphological characterization and mechanical testing confirmed robust interfacial bonding, while accelerated reliability tests (HAST, IOL and TCT) validated long-term performance. The results highlight the feasibility of adopting pressure-less sintered silver on unmodified Cu substrates, offering a cost-effective, high-reliability solution for next-generation high-power SiC applications.