Effect of thermal cycling on reliability of solder joints of ceramic column grid array package

Ceramic column grid array (CCGA) packages have been extensively used in high-reliability industry based on their advantages such as excellent electrical and thermal performances, high-density signal interconnection. However, due to package form and characteristics of material, the crack propagation of solder joint under thermal cycling load needs to be seriously focused on. This paper took CCGA484 as an example, the evolution of solder column morphology, microstructure and shear strength of solder joints under −65 ~ 150 ℃ thermal cycling load was investigated. The result showed that, during the thermal cycling, the creep behavior was gradually occurred on solder columns of CCGA board-level package. The microstructure of solder joints showed that intermetallic compound (IMC) of Ni₃Sn₄, Ni₃Sn₂ and Ni₃Sn were successively found in the solder joints interface, and the total thickness had an increasing trend. As hard and brittle phases, the increasing of IMC thickness could give rise to intensifying the stress concentration, which finally causing cracking failure of solder joints. Correspondingly, the shear strength of the solder joints were gradually deteriorated.