Microstructure of Ag Nano Paste Joint and Its Influence on Reliability

In this paper, the microstructure of Ag nano paste joint was investigated in pressure-less sintering conditions, and influence on joint’s reliability studied. Firstly, silver nanoparticles (Ag NPs) were synthesized using redox reaction method. To tightly stack NPs paste, with sizes 30~50 nm submicron-sized particles mixed. It found that increasing temperature or time can reduce porosity bonding layer interfacial crack simultaneously, resulting higher shear strength. When at a 250 °C, complete interface formed, 0.68 ?m interdiffusion layer. At (300 °C), reached 1.5 ?m, providing 35.9 ± 1.7 MPa The die attachment analyzed under thermal shocking from ?65 °C to 150 for 50 cycles. As could quickly grow through defects, separation ratio 85% 67% when sintered 200 respectively. Because reliable between substrate, formed slight edge °C. 300 small voids became large voids, which featured lower resistance growth. Thus, instead further improved reliability, increased 37%.