*Article* **A Reliable Way to Improve Electrochemical Migration (ECM) Resistance of Nanosilver Paste as a Bonding Material**

**Zikun Ding 1, Zhichao Wang 2, Bowen Zhang 3, Guo-Quan Lu <sup>4</sup> and Yun-Hui Mei 3,\***


**Abstract:** Electrochemical migration (ECM) of sintered nano-Ag could be a serious reliability concern for power devices with high-density packaging. An anti-ECM nano-Ag-SiOx paste was proposed by doping 0.1wt% SiOx nanoparticles rather than previously used expensive noble metals, e.g., palladium. The ECM lifetime of the sintered nano-Ag-SiOx was 1.5 to 3 times longer than that of the sintered nano-Ag, due to the fact that the SiOx could protect the Ag from oxidation. The thermomechanical reliability of the sintered nano-Ag-SiOx was also improved by sintering under 5 MPa assisted pressure. The lesser porosity and smaller grain boundaries of the sintered nano-Ag-SiOx could also be beneficial to retard the silver ECM. In the end, a double-sided semiconductor device was demonstrated to validate the better resistance to the ECM using the sintered nano-Ag-SiOx.

**Keywords:** electrochemical migration; ionic migration; sintering; nanosilver; doping; Ag nanoparticles; reliability
