Simultaneous Enhancement of Electrochemical Migration Lifetime and Reliability of Sintered Silver

The high operation temperature and large voltage bias service environments of wide bandgap (WBG) devices often result in the failure of sintered silver layer due to electrochemical migration (ECM). Herein, novel silver-based paste was prepared by incorporating 5 wt% In particles (Ag-5%In), which effectively balanced the ECM lifetime and the reliability of bonding samples. During high temperatures (400 °C) and high voltages (400 V) ECM tests, the preferential formation of In2O3 in Ag-5%In paste effectively inhibited the oxidation and ionization processes of Ag, thereby prolonging the ECM failure time from 462 min to 839 min. In addition, the formation of Ag-In intermetallic compounds (IMCs) and the densification of interconnection layer resulted in high reliability of Ag-5%In paste during the thermal shock test (TST), with the average shear strength remaining around 24.6 MPa after 1000 TST cycles. The comprehensive ECM and mechanical reliability make the proposed Ag-5%In paste a promising packaging material for high-temperature and high-voltage applications of WBG devices.