Accelerated testing and finite element analysis of PBGA under multiple environmental loadings

To investigate the long term reliability of plastic ball grid array (PBGA) packages in aerospace applications, accelerated tests were conducted to non-underfilled and underfilled packages under multiple environmental loadings at board level. This paper discusses the test results and the underfill effect on solder joint reliability. Failure modes and sites were identified through failure analysis on test samples. To better understand the thermomechanical behavior of PBGAs under cyclic thermal loading environments, three dimensional FEA models for non-underfilled and underfilled packages were also developed and used to predict the time to failure.