Failure Mechanisms of Ball Grid Array Packages Under Vibration and Thermal Loading

Automotive electronics face increasing reliability challenges in meeting thermal and vibration requirements. This paper addresses these challenging issues through an overview of automotive application environments; their corresponding accelerated life tests, and physics of failures. The accelerated load level is determined by industry-accepted formulations. Basis of accelerated life testing for both thermal and vibration is discussed. Dynamic difference in loading frequency and magnitude leads to different failure mechanisms. Under thermal and vibration loading conditions, fatigue domains and commonly observed failure modes of electronic components are further characterized in terms of low cycle and high cycle fatigue. Material behaviors under these loading conditions are also discussed with experimental and analytical results. In particular, failure mechanisms of ball grid array (BGA) packages are presented for thermal and vibration loading conditions. Observed failure mechanisms of solder balls are further correlated with analytical results from finite element modeling. Structural and loading parameters that impact BGA failure are analyzed to provide guidance on packaging and board layout.