An Efficient Network Model for Determining the Effective Thermal Conductivity of Particulate Thermal Interface Materials

Particulate composites are commonly used in Microelectronics applications. One example of such materials is Thermal Interface Materials (TIMs) that are used to reduce the contact resistance between the chip and the heat sink. The existing analytical descriptions of thermal transport in particulate systems do not accurately account for the effect of inter-particle interactions, especially in the intermediate volume fractions of 30-80%. Another crucial drawback in the existing analytical as well as the network models is the inability to model size distributions (typically bimodal) of the filler material particles that are obtained as a result of the material manufacturing process. While full-field simulations (using, for instance, the finite element method) are possible for such systems, they are computationally expensive. In the present paper, we develop an efficient network model that captures the physics of inter-particle interactions and allows for random size distributions. Twenty random microstructural arrangements each of Alumina as well as Silver particles in Silicone and Epoxy matrices were generated using an algorithm implemented using a java language code. The microstructures were evaluated through both full-field simulations as well as the network model. The full-field simulations were carried out using a novel meshless analysis technique developed in the author’s (GS) research [26]. In all cases, it is shown that the random network models are accurate to within 5% of the full field simulations. The random network model simulations were efficient since they required two orders of magnitude smaller computation time to complete in comparison to the full field simulation

Special Section on Components and Packaging Technologies With Contributions From ITherm 2002 Thermal Management Track

Originally published in IEEE Transactions on Components and Packaging Technology Vol. 26 No. 1. IEEE holds all copyright of this article. IEEE allows the final published version of author's own work to be deposited in institutional repositories.ITHERM 2002, the 8th Intersociety Conference on Thermal, Mechanical and Thermomechanical Phenomena in Electronic Systems, hosted approximately 500 international experts in the areas of thermal management, thermomechanical and mechanics issues, and emerging technologies in electronic packaging and systems in San Diego, CA, May 30–June 1, 2002. The Technical Program included nearly 150 peer-reviewed papers presented in 35 sessions arranged into three Tracks: Thermal Management, Applied Mechanics, and Emerging Technologies. Twenty-five of these sessions were in the area of Thermal Management. This represented an increase in the number of presented papers and attendance compared with ITherm 2000, in spite of an economic downturn in the intervening period. Three special issues of the CPMT IEEE TRANSACTIONS ON COMPONENTS AND PACKAGING TECHNOLOGIES have been planned, one for each Track. The papers appearing in this Special Issue are in the area of thermal management and have been nominated by session chairs for consideration for the ITherm 2002 Best Paper in the Thermal Management Track. In addition, three of the six Keynote Speeches have also been included in this Special Issue. These papers reflect a broad range of current interest topics covered in the area of thermal management at ITherm 2002. Of the sixteen papers selected for this Special Issue, eleven have been accepted for publication after peer review