Analytical Thermo-Mechanical Model for Non-Underfilled Area Array Flip Chip Assemblies

[+] Author and Article Information
Bart Vandevelde, Eric Beyne

IMEC, Kapeldreef 75, B-3001 Leuven, Belgium

Dirk Vandepitte, Martine Baelmans

Catholic University of Leuven, Celestijnenlaan 300B, B-3001 Leuven, Belgium

J. Electron. Packag 126(3), 351-358 (Oct 06, 2004) (8 pages) doi:10.1115/1.1772416 History: Received July 01, 2003; Revised January 01, 2004; Online October 06, 2004
Copyright © 2004 by ASME
Your Session has timed out. Please sign back in to continue.


The Nordic Electronics Packaging Guideline, http://extra.ivf.se/ngl
Vandevelde, B., Beyne, E., Vandepitte, D., and Baelmans, M., 2002, “Semi-Analytical Model for Calculation of Induced Strains in Solder Joints of Underfilled Flip Chip Assemblies,” Proceedings of the 3rd Eurosime conference, pp. 86–91, Paris, France, April 14–17.
Vandevelde,  B., Christiaens,  F., Beyne,  E., Peeters,  J., Allaert,  K., Vandepitte,  D., and Berghmans,  J., 1998, “A Thermo-Mechanical Model for Leadless Solder Interconnections in Flip Chip Assemblies,” IEEE Trans. Compon., Packag. Manuf. Technol., Part A, 21, pp. 177–185.
Suhir, E., 1988, “Thermal Stress Failures in Microelectronic Components—Review and Extension,” Advances in Thermal modelling of Electronic Components and Systems, A. Bar-Cohen and A. D. Kraus, eds., New York, Hemisphere, Vol. 1, Ch. 5, pp. 337–412.
Tummala, R. R., and Rymaszewski, E. S., 1989, Microelectronics Packaging Handbook, Van Nostrand Reinhold, New York.
Jeanotte, D., Goldmann, L., and Howard, R., 1989, Package Reliability, Micro-electronics Handbook, R. Tummala and E. Rymaszewski, eds., New York, Van Nostrand Reinhold, Ch. 5, pp. 295–299.
Robert,  M., and Keer,  L. M., 1987, “An Elastic Cylinder With Prescribed Displacements at the Ends—Asymmetric Case,” Quart. Journal on Applied Mathematics ,40, pp. 365–381.
Hall,  P. M., 1984, “Forces, Moments and Displacements During Thermal Chamber Cycling of Leadless Ceramic Chip Carriers Soldered to Printed Circuit Boards,” IEEE Trans. Compon., Hybrids, Manuf. Technol., CHMT-7, pp. 314–327, Dec.
Chen,  W. T., and Nelson,  C. W., 1979, “Thermal Stress in Bonded Joints,” IBM J. Res. Dev., 23(2), pp. 179–188, March.
Lau,  J. H., Rice,  D. W., and Avery,  P. A., 1987, “Elasto-Plastic Analysis of Surface Mount Solder Joints,” IEEE Trans. Compon., Hybrids, Manuf. Technol., CHMT-10, pp. 346–357.
Engelmaier,  W., 1983, “Fatigue of Leadless Chip Carrier Solder Joints During Power Cycling,” IEEE Trans. Compon., Hybrids, Manuf. Technol., CHMT-6, pp. 232–237.
Vandevelde, B., and Beyne, E., 1998, “Thermo-Mechanical Analysis for Optimizing the Underfill Material Properties of Flip Chip Assemblies,” SEM Spring Conference on Experimental/Numerical Mechanics in Electronic Packaging, Houston, USA, June 1–3.
Vandevelde, B., 2002, “Thermo-Mechanical Modelling of Solder Joint Reliability for Electronic Package Systems,” PhD thesis, Catholic University of Leuven; March.


Grahic Jump Location
Principle of the analytical calculations for the thermo-mechanical model
Grahic Jump Location
Schematic drawing of the area array thermo-mechanical model
Grahic Jump Location
Numbering of the elements in the area array model
Grahic Jump Location
Forces acting between the components 1, 2, and the n joints
Grahic Jump Location
Internal forces acting on the components and joints
Grahic Jump Location
Magnified view of the deformations U1,U2,Uc+ and Uc
Grahic Jump Location
Internal load distribution in the joint (bjoint=out-of-plane joint thickness)
Grahic Jump Location
Normal and shear stresses caused by forces F and N and moments Mc1 and Mc2
Grahic Jump Location
Normal and shear stresses caused by local thermal mismatches
Grahic Jump Location
2D plain strain FEM for a 25×25 area array chip assembled to an alumina carrier. The plain strain elements have also an out-of plane thickness which is 0.1 mm for the joint elements and 0.2 mm (=pitch) for the chip and alumina elements.
Grahic Jump Location
Warpage of chip and alumina components calculated by the analytical model and by FEM (warpage in neutral fibre of the components)
Grahic Jump Location
Forces and moments acting on the area array joints (analytical model)
Grahic Jump Location
Forces and moments acting in the different sections of the top and bottom component (analytical model)
Grahic Jump Location
Maximum Von Mises stress in each joint of a 25×25 area array flip chip assembly (calculated by FEM and analytical model)
Grahic Jump Location
Maximum σVM in each joint of an area array assembly with different array sizes
Grahic Jump Location
Effect of h2 on the edge joint forces N and F (p=0.2 mm, 25×25 area array)
Grahic Jump Location
Effect of joint height hc. The force F is decreasing with increasing hc, but the joint moments Mc1,2 are dependent on the product of F and hc. (At small hc, the FEM results are not following the stress rise calculated by the analytical model. As a fixed element size is chosen, the element stress is almost the average stress over the whole small joint.



Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In