Thermal Resistance of Particle Laden Polymeric Thermal Interface Materials

Abstract

Particle laden polymers are one of the most prominent thermal interface materials (TIM) used in electronics cooling. Most of the research has primarily dealt with the understanding of the thermal conductivity of these types of TIMs. For thermal design, reduction of the thermal resistance is the end goal. Thermal resistance is not only dependent on the thermal conductivity, but also on the bond line thickness (BLT) of these TIMs. It is not clear which material property(s) of these particle laden TIMs affects the BLT and eventually the thermal resistance. This paper introduces a rheology based semi-empirical model for the prediction of the BLT of these TIMs. BLT depends on the yield stress of the particle laden polymer and the applied pressure. The BLT model combined with the thermal conductivity model can be used for modeling the thermal resistance of these TIMs for factors such as particle volume faction, particle shape, base polymer viscosity, etc. This paper shows that there exists an optimal filler volume fraction at which thermal resistance is minimum. Finally this paper develops design rules for the optimization of thermal resistance for particle laden TIMs.

Anisotropic Thermal and Electrical Properties of Thin Thermal Interface Layers of Graphite Nanoplatelet-Based Composites

“…Conventional TIMs are manufactured by introducing highly thermally conductive fillers, like metal or metal oxide microparticles, into the polymer matrix345. With the rise of graphene6, a product of graphite exfoliation78, graphite nanoplatelets (GNPs), have been receiving significant attention as a new form of thermally conducting filler9101112131415161718192021222324.…”

Electronics Thermal Management in Information and Communications Technologies: Challenges and Future Directions

“…During this period, the thermal community responded with several initiatives that improved TIMs [32,33,34,35], thermal metrology [36,37], modelling [38,39] and various building block technologies such as microchannel heatsinks [40,41,42,43,44], ionic wind [45], heat pipes [46,47], and thermoelectric coolers [48,49]. It also saw the emergence of major research efforts funded in the US by DARPA programs such as HERETIC (starting 1992), followed by nTIM, MACE, TGP, NJTT, and ACM (2008), and most recently by the Intra/Interchip Enhanced Cooling (ICECool) program (2012).…”

Effects of Multi-modal Filler Size Distributions on Thermal Conductivity of Electrically Conductive Adhesives Containing Ag Micro and Nanoparticles

“…Therefore, the development of high-performance thermal interface materials (TIMs), including thermal greases, gels, adhesives and phase-change materials, is essential in order to advance the thermal management of microsystems such as those mentioned above. [2] Among the various types of TIMs that are available, the present work focuses on the heatresistant conductive adhesives that are required for highpower die-attach applications.…”