Thermal reliabilities of Sn-0.5Ag-0.7Cu-0.1Al2O3/Cu solder joint

The effects of trace addition of Al2O3 nanoparticles (NPs) on thermal reliabilities of Sn-0.5Ag-0.7Cu/Cu solder joints were investigated. Experimental results showed that trace addition of Al2O3 NPs could increase the isotheraml aging (IA) and thermal cyclic (TC) lifetimes of Sn-0.5Ag-0.7Cu/Cu joint from 662 to 787 h, and from 1597 to 1824 cycles, respectively. Also, trace addition of Al2O3 NPs could slow down the shear force reduction of solder joint during thermal services, which was attributed to the pinning effect of Al2O3 NPs on hindering the growth of grains and interfacial intermetallic compounds (IMCs). Theoretically, the growth coefficients of interfacial IMCs in IA process were calculated to be decreased from 1.61x10-10 to 0.79x10-10 cm2/h in IA process, and from 0.92x10-10 to 0.53x10-10 cm2/h in TC process. This indicated that trace addition of Al2O3 NPs can improve both IA and TC reliabilities of Sn-0.5Ag- 0.7Cu/Cu joint, and a little more obvious in IA reliability.

Automated summary

The effects of adding trace amounts of Al2O3 nanoparticles on the thermal reliabilities of Sn-0.5Ag-0.7Cu/Cu solder joints were investigated. The results showed that the addition of Al2O3 nanoparticles increased the lifespan of the joints under isothermal aging and thermal cyclic conditions. The nanoparticles also slowed down the reduction of shear force during thermal services, which was due to their pinning effect on hindering the growth of grains and interfacial intermetallic compounds.