Free standing thermal interface material based on vertical arrays composites

In power microelectronics, the trends towards miniaturization and higher performances result in higher power densities and more heat to be dissipated. For large systems, the associated thermal architecture is becoming more and more complex and costly. In most electronic assembly, thermal interface materials (TIM) help provide a path for the heat to be transferred from the hot source to a cooler heat sink but still represent a bottleneck in the total thermal resistance of the system. Increasing the dissipative capabilities of thermal interface materials is a widely tackled challenge. For this study we address more specifically the “gap filler” type of TIM. Typically located beneath packaged dies, it features height compensation capabilities, CTE mismatch handling, easy replacement and high thermal conductivity. We report here on the fabrication of a composite free standing film based on vertically aligned carbon nanotubes. Original processing methods are reported as well as first applicability assessments as thermal interface material.