Impact of Thermal Aging and Cycling on Reliability of Thermal Interface Materials
Authors: Tushar Chauhan, Abel Misrak, Rabin Bhandari, Pavan Rajmane, Raufur Chowdhury, Krishna Bhavana Sivaraju, Milad Abdulhasansari, Dereje Agonafer Company: The University of Texas at Arlington Date Published: 9/22/2019
Abstract: Thermal interface materials (TIMs) are critical for the thermal management of electronic packages. Different kinds of TIMs are currently used in the industry to reduce the contact thermal resistance and improve performance of electronic systems. Greases, elastomeric pads, epoxies, and thermally conductive gap fillers are some of the most common types of TIMs. While designing electronic systems, attention is given to characterizing the performance of TIMs and understanding the reliability of the TIM materials under different environmental loading conditions. The most common approach is to measure the thermal performance at the start and end of accelerated testing conditions. As the reliability study of TIMs is not a matured subject, there is a growing interest to understand the mechanical behavior of TIM materials and how they change under various environmental loading conditions. In this paper, four commercially available TIMs are studied under high temperature storage and thermal cycling loading conditions. In the first part of the work, the change in the thermal expansion coefficient of a representative of the group due to high temperature storage test is studied using Thermomechanical Analyzer (TMA). For the second part of the work, an assembly was made to the test the performance of the TIM materials under thermal cycling conditions. Samples with different TIM thickness were prepared and tested in an environmental chamber. An inspection was performed visually and with the aid of microscope. The results and lessons learnt are presented in this paper.