Heat Conduction in High Thermal Conductivity Networked Composite Films for Thermal Interface Materials

Fast and efficient exchange of thermal energy plays a vital role in the thermal management of electronic and optoelectronic devices. A critical component for thermal management is a thermal interface material (TIM) that is used to minimize the contact thermal resistance between surfaces and to provide a low resistance pathway to spread and remove heat. Ideal TIMs must pass several key requirements: 1) high thermal conductivity κ and low thermal contact resistance with the mating surfaces; 2) easy to apply with controlled thickness; 3) low temperature processing; 4) able to accommodate thermally induced mechanical stresses during on-off cycling of the device¹. Particle-based composites have reasonable slurry viscosities, however their thermal conductivity are usually very low (<10 Wm⁻¹K⁻¹), even when high κ nanofillers are employed, due to the thermal interface resistance between nanoparticles and the polymer matrix² or the absence of high κ pathways.