The transient liquid phase bonding by ultrasonic-assisted soldering of Cu contained Sn-58Bi solder paste for high-temperature packaging applications

Recently, high-temperature endurance bonding has been required for the increasing demands of SiC die attachment for SiC power modules. The TLPS process is one of the promising high-heat endurance bonding methods. The general TLPS process needs a long bonding time about 60 min. To decrease the bonding time, we applied ultrasonic vibration during the soldering process. The cavitation effect induced by ultrasonic vibration can accelerate the intermetallics formation reaction. Also, we conducted the die shear test to evaluate the mechanical property after the environmental reliability test. The ultrasonic-assisted soldered joints showed superior mechanical reliability after a high-temperature storage test.