Thermal interface materials (TIMs) are used in electronics cooling applications to decrease the thermal contact resistance between surfaces in contact. A methodology to determine the optimal volume fraction of filler particles in TIMs for minimizing the thermal contact resistance is presented. The method uses finite element analysis to solve the coupled thermo-mechanical problem. It is shown that there exists an optimal filler volume fraction which depends not only on the distribution of the filler particles in a TIM but also on the thickness of the TIM layer, the contact pressure and the shape and the size of the filler particles. A contact resistance alleviation factor is defined to quantify the effect of these parameters on the contact conductance with the use of TIMs. For the filler and matrix materials considered—platelet-shaped boron nitride filler particles in a silicone matrix—the maximum observed enhancement in contact conductance with the use of TIMs was by a factor of as much as 9.


This is the Publisher PDF version of V. Singhal, T. Siegmund, S.V. Garimella, “Optimization of thermal interface materials for electronics cooling applications,” IEEE CPMT - Institute of Electrical and Electronics Engineering Transactions on Components and Packaging Technologies, 27 (2004) 244-252. © 2004 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works.

It is available at http://dx.doi.org/10.1109/TCAPT.2004.828587 and is made available here with the permission of IEEE.

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