Skip to the content of the web site.

Sponsored Research

Effective Thermal Conductivity of Composite Thermal Interface Materials

Student: Paul Karayacoubian
Status: M.A.Sc. candidate
Sponsor: Center for Microelectronics
Assembly and Packaging
Project Title: Design and Analytical Modeling
of New Thermal Interface
Particle-laden polymers are the latest Thermal Interface Materials (TIMs) being investigated for the minimization of thermal joint resistance in microelectronics applications. A fundamental problem which remains to be addressed is how to predict the effective thermal conductivity of these materials. My project involves investigating the effects of the volume fraction of the dispersed phase, particle geometry, distribution, and orientation. Analytical models are verified with numerical and experimental results.
1. P. Karayacoubian, M. M. Yovanovich, J. R. Culham, 2006, "Thermal Resistance-Based Bounds for the Effective Conductivity of Polymeric Thermal Interface Materials," Semi-Therm 2005, March 14-16, Dallas, TX.
2. P. Karayacoubian, M. Bahrami, J. R. Culham, 2005, "Asymptotic Solutions of Effective Thermal Conductivity," ASME International Mechanical Engineering Congress and Exposition, November 5-11, Orlando, FL.


Thermal Contact Resistance of Polymer-Polymer Joints

Student: Josh Gibbins
Status: M.A.Sc. candidate
Sponsor: Center for Microelectronics Assembly & Packaging
Project Title: Air Cooling Limits
When heat flows through a contact formed at a polymer/polymer interface there is a temperature drop as a result of the thermal contact resistance (TCR) resulting from the imperfect contact.
This study will look at experimentally determining the TCR of a polymer/polymer joint under various interface contact pressures. Experimental data will then be compared to existing TCR models (both plastic and elastic). This entails having both the micro-hardness and the surface roughness of the polymer, both of which will be looked at in detail. To experimentally determine the TCR of a polymer-polymer joint a minimal amount of heat must be used or the polymer samples will be permanently deformed. To ensure the polymer remains in a stiff, glassy state a polymer with a high glassy temperature must be used. Polycarbonate was selected for this reason and is the primary polymer used for this study.
Publications: NA