Molecular Dynamics Study on Thermal Performance of CNT-array-Thermal Interface Material

Carbon nanotubes (CNT) are an attractive candidate to form thermal interface material (TIM) and improve the thermal management performance of microelectronic packages. In this paper, thermal performance of CNT-array-TIM was predicted by nonequilibrium molecular dynamics simulation. The ab initio forcefield COMPASS (Condensed-phase Optimized Molecular Potentials for Atomistic Simulation Studies) was adopted to model interatomic chemical bonding and non-bonding potential energy. A constant heat flux was imposed on the system and the resulting temperature gradient was calculated to obtain the thermal conductivity. The effects of the diameter of CNT and the temperature on the thermal conductivity of CNT-array-TIM were studied. It was demonstrated that significantly drop of thermal conductivity of CNT-array-TIM occured with the temperature increases up to room temperature. However, it will not reduce much with the temperature further increase. It was also found that the thermal conductivity of CNT-array-TIM increased with the increased diameter of the armchair CNT.