Abstract
The moisture absorption experiments of two kinds of molding compound are conducted. The diffusion at low temperature and humidity observes the Fick’s Law, but it does not strictly obey at higher temperature and humidity. The phenomena can be attributed to the occurrence of the second phase, and the Fick’s Law can be modified by diffusion coefficient varying with the moisture concentration. The predicted value by the modified Fick’s Law agrees with the test data. At certain temperature, the saturated moisture content of molding compound is proportional to the relative humidity, and the proportional factor is the product of solubility and saturated vapor pressure. The solubility is a physical characteristic, which has no relations with the relative humidity of ambient air.
Issue Section:
Research
Papers
1.
Wong
, E. H.
, and Rajoo
, R.
, 2003, “Moisture Absorption and Diffusion Characterisation of Packaging Materials-Advanced Treatment
,” Microelectron. Reliab.
0026-2714, 43
, pp. 2087
–2096
.2.
Tay
, A. A. O.
, and Lin
, T. Y.
, 1996, “Moisture Diffusion and Heat Transfer in Plastic IC Package
,” IEEE Trans. Compon., Packag. Manuf. Technol., Part A
1070-9886, 19
, pp. 186
–193
.3.
Kitano
, M.
, Nishimura
, A.
, and Kawai
, S.
, 1988, “Analysis of Package Cracking During Reflow Soldering Process
,” IEEE in Proceedings 26th International Reliability Physics Symposium
, pp. 90
–95
.4.
Roy
, S.
, Xu
, W. X.
, Park
, S. J.
, and Liechti
, K. M.
, 2000, “Anomalous Moisture Diffusion in Viscoelastic Polymers: Modeling and Testing
,” ASME J. Appl. Mech.
0021-8936, 67
, pp. 391
–396
.5.
Lin
, T. Y.
, and Tay
, A. A. O.
, 1997,“Dynamics of Moisture Diffusion, Hygrothermal Stresses and Delamination in Plastic IC Packages
,” ASME Advances in Electronic Packaging
, 19-2
, pp. 1429
–1436
.6.
Zhang
, G. Q.
, Tay
, A. A. O.
, Ernst
, L. J.
, Liu
, S.
, Qian
, Z. F.
, Bressers
, H. J. L.
, and Janssen
, J.
, 2001, “Virtual Thermo-Mechanical Prototyping of Electronic Packaging-Challenges in material characterization and modeling
,” in Proceedings of the 51st Electronic Components and Technology Conference
, pp. 1479
–1486
.7.
Wong
, E. H.
, Chan
, K. C.
, Lim
, T. B.
, and Lam
, T. F.
, 1999, “Non-Fickian Moisture Properties Characterisation and Diffusion Modeling for Electronic Package
,” IEEE Electronic Components and Technology Conference
, pp. 302
–306
.8.
Bhattacharyya
, B. K.
, Huffman
, W. A.
, Jahsman
, W. E.
, and Natarajan
, B.
, 1988, “Moisture Absorption and Mechanical Performance of Surface Mountable Plastic Packages
,” in Proceedings of the 38th Electronics Components Conference
, pp. 49
–58
.9.
Frémont
, H.
, Delétage
, J. Y.
, Pintus
, A.
, and Danto
, Y.
, 2001, “Evaluation of the Moisture Sensitivity of Molding Compounds of IC’s Packages
,” ASME J. Electron. Packag.
1043-7398, 123
, pp. 407
–412
.10.
Ferguson
, T.
, and Qu
, J.
, 2003, “Moisture Absorption Analysis of Interfacial Fracture Test Specimens Composed of No-Flow Underfill Materials
,” ASME J. Electron. Packag.
1043-7398, 125
, pp. 24
–30
.11.
McCabe
, W. M.
, Smith
, J. C.
, and Harriott
, P.
, 2001, Unit Operations of Chemical Engineering
, 6th ed., McGraw-Hill
, New York.12.
Roy
, S.
, 1999, “Modeling of Anomalous Diffusion in Polymer Matrix Composites: A Finite Element Approach
,” J. Compos. Mater.
0021-9983, 33
, pp. 1318
–1343
.13.
Frisch
, H. L.
, 1966, “Irreversible Thermodynamics of Internally Relaxing Systems in the Vicinity of the Glass Transition
,” Non-Equilibrium Thermodynamics, Variational Techniques, and Stability
, R. J.
Dennelly
, R.
Herman
, and I.
Prigogine
, eds., University of Chicago Press
, Chicago, IL, pp. 277
–280
.14.
Crank
, J.
, 1975, The Mathematics of Diffusion
, 2nd ed., Oxford University Press
, Oxford, UK.15.
Frisch
, H. L.
, 1964, “Isothermal Diffusion in Systems with Glasslike Transitions
,” J. Chem. Phys.
0021-9606, 41
, pp. 3379
–3683
.16.
Weitsman
, Y.
, 1987, “Stress Assisted Diffusion in Elastic and Viscoelastic Materials
,” J. Mech. Phys. Solids
0022-5096, 35
, pp. 73
–93
.17.
Biot
, M. A.
, 1956, “Thermoelasticity and Irreversible Thermodynamics
,” J. Appl. Phys.
0021-8979, 27
, pp. 240
–253
.18.
Schapery
, R. A.
, 1969, “Further Development of a Thermodynamic Constitutive Theory: Stress Formulation
,” A&S Report No. 69-2, Purdue University
, West Lafayette, IN.Copyright © 2005
by American
Society of Mechanical Engineers
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