Characterization of metal micro-textured thermal interface materials

To address performance limitations of conventional thermal interface materials (TIMs), a metal micro-textured thermal interface material (MMT-TIM) has been developed that consists of a thin metal foil with raised micro-scale features that plastically deform under an applied pressure thereby creating a continuous, thermally conductive, path between the mating surfaces. Here, the influence of various geometrical parameters on the mechanical and thermal performance of hollow conical MMT-TIMs is investigated experimentally. The results demonstrate the influence of feature size, shape, array density and foil thickness. The results also serve to highlight the underlying challenge of characterizing the thermal contact resistance of MMT-TIMs. Future efforts for this project are discussed including the validation of a numerical thermal-mechanical model and development of a relationship between electrical and thermal contact resistance for MMT-TIMs that would allow estimation of the thermal contact resistance using a straightforward electrical measurement. ©EDA Publishing/THERMINIC 2009.