Ultrasonic Bonding of Ag Ribbon on Si Wafers With Various Backside Metallization

Ultrasonic ribbon bonding has gained much attention due to the endeavor of achieving higher module performance in power electronic packaging. Among all the ribbon materials, Ag ribbon is a promising candidate due to its superior electrical properties. However, research which has reported the bonding of the ribbon on chip side is scant. Thus, in this study, the authors carried out bonding of the Ag ribbon on various types of metallized wafers to examine the feasibility of Ag ribbon, simulating the bonding scenario on the chip side in power modules. Results revealed that bonding of the Ag ribbon is feasible on those wafers metallized Ag on top. The authors also discussed the implications for the bondability of Ag ribbon with different types of metallization layers.