In this paper, the creep and relaxation behaviors of a wafer-level CSP assembly under two types of thermal loading conditions were investigated using high sensitivity moire´ interferometry. One is a thermal load from 100°C to room temperature and the other is from room temperature to 100°C. In the second case, the real-time technique was used to monitor and measure the shear deformations of solder joints and the warpage of the assembly during the test. For the real-time measurements of thermal deformations, a small-sized thermal chamber having an optical window was developed. In addition, the test results obtained from the moire´ interferometry measurements were compared with the predicted values obtained from finite element analysis. It is shown that the deformation values predicted from finite element analysis have a good agreement with those obtained from the tests.

Issue Section:
Additional Technical Papers
Keywords:
chip scale packaging, creep, shear deformation, anelastic relaxation, moire fringes, light interferometry, soldering, finite element analysis
Topics:
Creep, Deformation, Finite element analysis, Interferometry, Manufacturing, Relaxation (Physics), Semiconductor wafers, Shear (Mechanics), Solders, Temperature, Solder joints, Modeling, Displacement, Diffraction gratings, Warping, Shear deformation
1.
Kim, D. H. et al., 1999, “Electrical Performance of a Lead Frame CSP and a Wafer Level CSP for DRAM Applications,” Proc., Fourth Annual Pan Pacific Microelectronics Symposium, Kauai, HI, pp. 79–84.
2.
Yang, H., Larson, A., Barrett, S. T., and Elenius, P., 1998, “Reliability Evaluation of Ultra CSP™ Packages,” Proc. SMTA, 5th Annual Emerging Technologies Symposium, Chandler, AZ, November 16–18, pp. 85–92.
3.
Yang, H. et al., 2000, “Reliability Characterization in Ultra CSP™ Package Development,” IEEE 50th ECTC, Las Vegas, NV, May 21–24.
4.
Guo
,
Y.
,
Lim
,
C. K.
,
Chen
,
W. T.
, and
Woychik
,
C. G.
,
1993
, “
Solder Ball Connect (SBC) Assemblies under Thermal Loading: I. Deformation Measurement via Moire´ Interferometry, and Its Interpretation
,”
IBM J. Res. Dev.
,
37
, pp.
625
–
647
.
5.
Han
,
B.
, and
Guo
,
Y.
,
1995
, “
Thermal Deformation Analysis of Various Electronic Packaging Products by Moire´ and Microscopic Moire´ Interferometry
,”
ASME J. Electron. Packag.
,
117
, pp.
185
–
191
.
6.
Han, B., Caletka, D., and Guo., Y., 1995, “On The Effect of Moire´ Specimen Preparation on Solder Ball Strains of Ball Grid Array Package Assembly,” Proc., 1995 SEM Spring Conference on Experimental Mechanics, Grand Rapid, MI, pp. 115–120.
7.
Han
,
B.
,
Guo
,
Y.
,
Lim
,
C. K.
, and
Caletka
,
D.
,
1996
, “
Verification of Numerical Models Used in Microelectronics Packaging Design by Interferometric Displacement Measurement Methods
,”
ASME J. Electron. Packag.
,
118
, pp.
157
–
163
.
8.
Han
,
B.
,
1997
, “
Deformation Mechanism of Two-Phase Solder Column Interconnections Using Highly Accelerated Thermal Cycling Condition: An Experimental Study
,”
ASME J. Electron. Packag.
,
119
, pp.
189
–
196
.
9.
Han
,
B.
,
1998
, “
Recent Advancements of Moire´ and Microscopic Moire´ Interferometry for Thermal Deformation Analyses of Microelectronics Devices
,”
Exp. Mech.
,
38
(
4
), pp.
278
–
288
.
10.
Wang
,
J.
,
Qian
,
Z.
,
Zou
,
D.
, and
Liu
,
S.
,
1998
, “
Creep Behavior of a Flip-Chip Package by Both FEM Modeling and Real Time Moire´ Interferometry
,”
ASME J. Electron. Packag.
,
120
, pp.
179
–
185
.
11.
Zhao, Y., Dishongh, T., Cartwright, A., and Basaran, C., 1999, “Creep Behavior of BGA Solder Joints During Thermal Cycling By Moire´ Interferometry,” Advances in Electronic Packaging, EEP-Vol. 26-1, pp. 685–691.
12.
http://www.photomechanics.com.
13.
ABAQUS, User’s Manual, Ver. 5.8, HKS Inc.
14.
Darveaux, R. et al., 1994, “Reliability of Ball Grid Array Solder Joints,” Ball Grid Array Technology, Chap. 13, ed., J. H. Lau, McGraw-Hill.
Copyright © 2003
 by ASME
You do not currently have access to this content.