Article thumbnail

Stresses from flip-chip assembly and underfill; measurements with the ATC4.1 assembly test chip and analysis by finite element method

By D.W. Peterson, J.N. Sweet, S.N. Burchett and A. Hsia


The authors report the first measurements of in-situ flip-chip assembly mechanical stresses using a CMOS piezoresistive test chip repatterned with a fine pitch full area array. A special printed circuit board substrate was designed at Sandia and fabricated by the Hadco Corp. The flip-chip solder attach (FCA) and underfill was performed by a SEMATECH member company. The measured incremental stresses produced by the underfill are reported and discussed for several underfill materials used in this experiment. A FEM of a one-quarter section of the square assembly has been developed to compare with the measured as-assembled and underfill die surface stresses. The initial model utilized linear elastic constitutive models for the Si, solder, underfill, and PC board components. Detailed comparisons between theory and experiment are presented and discussed

Topics: Stresses, Piezoelectricity, Printed Circuits, Stress Analysis, Theoretical Data, Experimental Data, Finite Element Method, Comparative Evaluations, 42 Engineering Not Included In Other Categories
Publisher: Sandia National Laboratories
Year: 1996
DOI identifier: 10.2172/463650
OAI identifier:
Provided by: UNT Digital Library
Download PDF:
Sorry, we are unable to provide the full text but you may find it at the following location(s):
  • (external link)
  • Suggested articles

    To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.