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Underfill Encapsulant Flow Measured using Capacitance Measurement Techniques

Published online by Cambridge University Press:  21 March 2011

T. E. Driscoll
Affiliation:
Department of Physics, Binghamton University, Binghamton, N. Y. 13902
G. L. Lehmann
Affiliation:
Department of Mechanical Engineering, Binghamton University, Binghamton, N. Y. 13902
E. J. Cotts
Affiliation:
Department of Physics, Binghamton University, Binghamton, N. Y. 13902
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Abstract

Capillary flows of dense, model suspensions and industrial underfill encapsulants are investigated. Flow behavior is characterized by measuring the infiltration rate of an encapsulant or model suspension into a channel formed by parallel surfaces. A capacitance measurement technique is used to track the advancement of the front. Significantly this technique allows the channel surfaces to be formed from opaque materials such as those that found in the principal industrial application of electronics packaging. A scaling law to describe the functional dependence of the front position on channel spacing, surface tension and viscosity is presented.

Type
Research Article
Copyright
Copyright © Materials Research Society 2001

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References

REFERENCES

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