Optimal bonding of 4H-SiC parallel diodes in a single TO-247 package for improved surge current robustness: experimental investigation

In this study, the surge current capability of a 60 A–1200 V 4H-SiC diode fabricated by paralleling two 30 A dies is experimentally evaluated. Three bond wire configurations are investigated using a non-repetitive surge current test at 25 °C and 110 °C. The results reveal that the stitch configuration, which employs 3 × 20 mil bonding wires, significantly outperforms the alternative 4 × 15 mil and 4 × 12 mil counterparts in terms of maximum surge current robustness. An extensive analysis is also conducted to identify key differences in the failure mechanisms among the three configurations during surge current stress. • Surge robustness of 60 A SiC diodes assessed for three bond-wire layouts. • Stitch layout (3 × 20 mil) achieves highest IFSM, meeting the 10× rating at 25 °C. • 4 × 12 and 4 × 15 mil bonds show significantly lower surge-current capability. • Failure analysis reveals distinct thermal and structural damage mechanisms. • Larger contact area in stitch layout reduces heating and enhances diode survival.