TABLE OF CONTENTS T.E.Wong
Raytheon Electronic Systems, EI Segundo, California, USA
C.Y.Lau
Raytheon Electronic Systems, EI Segundo, California, USA
H.S.Fenger
Raytheon Electronic Systems, EI Segundo, California, USA
Received: 12 September 2003
Revised: 1 February 2004
Soldering & Surface Mount Technology
16/2 [2004] 41 45
Emerald Group Publishing Limited
[ISSN 0954 0911]
[DOI: 10.1108/09540910410537327]
T.E. Wong, C.Y. Lau and H.S. Fenger
CBGA solder joint thermal fatigue life estimation by a simple method
The authors would like to thank L.A.Kachatorian from Raytheon Electronic Systems for his contribution to this work and Y.C.Cho, A.Mawer and T.Kaschmiedar from Mototrola for their valuable technical discussions.
Keywords
Soldering, Joining processes, Fatigue, Thermal properties of materials
Abstract
A simple analysis method was developed to determine the fatigue life of a ceramic ball grid array (CBGA) solder joint when exposed to thermal environments. The solder joint consists of a 90Pb/10Sn solder ball with eutectic SnPb solder on both top and bottom of the ball. A closed-form solution, based on the calculation of the equilibrium of the displacements within the electronic package assembly, was first derived in order to calculate the solder joint strains during temperature cycling. In the calculation, an iteration technique was used to obtain a convergent solution for the solder strains, and the elastic material properties were used for all the electronic package assembly components except for the solder materials. A fatigue life prediction model was established.
Usage of the ball grid array (BGA) has become popular in today s electronic hardware industry. Owing to the hermetic design requirement...
