Superior Bonding Reliability of Sintered Cu Bonding at Power Cycle Test

Compound semiconductor devices can operate at high junction temperatures of over 175 °C; however, the conventional die-bonding material becomes problematic due to the lack of bonding reliability. We have previously developed a Cu-bonding paste, HSCuN-004, and also demonstrated its superior thermal cycle life. In this study, the power cycle life of bonding using HSCuN-004, sintered Ag, and high lead solder was evaluated and compared. To prevent the breaking of wiring on the upper electrode, a press contact was applied on an upper electrode. The characteristic lifetimes of the devices die-bonded by HSCuN-004, sintered Ag, and high-lead solder were 77394, 41948, and 5450, respectively. The power cycle lives of sintering materials are significantly superior to that of high-lead solder. In addition, HSCuN-004 had a better power cycle life than that of sintered Ag despite the higher porosity. The shape parameter, 11.2 of HSCuN-004 is larger than 3.5 of sintering Ag; therefore, the spread of the failure distribution is narrower than that of sintering Ag.