Preparation and characterization of nano-inorganic materials coated multi-walled carbon nanotubes/epoxy composites for thermal interface materials

Recent developments of nanofabrication have enabled the miniaturization of electronic devices, allowing more electronic devices to be combined into a single device with a high performance. However, the complex devices have led to the escalation of power dissipation as well as the increasing heat flux at the interface between devices. Electronic devices were damaged by much heat accumulation, since the reliability of devices is dependent on the junction temperature. For example a small operating temperature difference (in the order of 10~15°C) can result in a two times reduction in the lifetime of a device. Carbon nanotubes with large aspect ratio and unique thermal properties can be as thermal dissipating filler for some nanocomposites. However, carbon nanotubes with high electrical conductivity will induce short leakage at the same time. For overcoming this problem, the objective of this research is to propose the surface modification technology by inorganic materials on the carbon nanotubes for thermal interfacial materials (TIM) applications. This research is to develop the surface modification technology by depositing alumina nanoparticles on the surface of the multi-walled carbon nanotubes (MWCNTs). TIMs were prepared from epoxy resin and various content of alumina @ MWCNTs (1~5 phrs) and then their volume resistivity with different loading alumina @ MWCNTs content can maintain round 10¹⁵ ohm*cm. The thermal conductivity of a TIM with 5 phrs alumina @ MWCNTs was 1.01 W/mK (increased 677% compared to neat epoxy resin with 0.13 W/m*K).