Title :
Failure analysis of solder bumped flip chip on low-cost substrates
Author :
Lau, John H. ; Chang, Chris ; Lee, S. -W Ricky
Author_Institution :
Express Packaging Syst. Inc., Palo Alto, CA, USA
Abstract :
Failure analyses of 63wt%Sn-37wt%Pb solder bumped flip chip assemblies with underfill encapsulant are presented in this study. Emphasis is placed on solder flowed-out, nonuniform underfill and voids, and delaminations. X-ray, scanning acoustic microscope, and tomographic acoustic micro-imaging techniques are used to analyze the failure samples. Also, cross sections are examined for a better understanding of the failure mechanisms. Furthermore, nonlinear, temperature-dependent, and fracture-mechanics finite element analyses are used to determine the effects of underfill-void sizes on the flip chip solder joint reliability
Keywords :
X-ray analysis; acoustic microscopy; acoustic tomography; delamination; encapsulation; failure analysis; finite element analysis; flip-chip devices; fracture mechanics; integrated circuit interconnections; integrated circuit modelling; integrated circuit packaging; lead alloys; tin alloys; voids (solid); Sn-Pb solder bumped flip chip assemblies; SnPb; X-ray analysis; cross sections; delaminations; failure analysis; failure mechanisms; failure samples; flip chip solder joint reliability; fracture-mechanics finite element analyses; low-cost substrates; nonlinear finite element analyses; nonuniform underfill; scanning acoustic microscopy; solder bumped flip chip; solder flow-out; temperature-dependent finite element analyses; tomographic acoustic micro-imaging; underfill encapsulant; underfill-void size; voids; Acoustic testing; Assembly; Copper; Costs; Failure analysis; Flip chip; Materials testing; Microscopy; Packaging; X-ray imaging;
Conference_Titel :
Electronics Manufacturing Technology Symposium, 1999. Twenty-Fourth IEEE/CPMT
Conference_Location :
Austin, TX
Print_ISBN :
0-7803-5502-4
DOI :
10.1109/IEMT.1999.804859
