Thermal interface material with aligned CNT and its application in HB-LED packaging

High density well aligned vertical CNT arrays were synthesized by thermal chemical vapor deposition (CVD) method on 1 inch by 1 inch Si substrates with sputtered Ti and Si layers. They were used as a new kind of thermal interface material (TIM) for the thermal management of microelectronic packages and high brightness light emitting diode (HB-LED) packages. The thermal resistance of the CNT-array-TIM and some other TIM were evaluated and compared according to ASTM D5470 standard. The thermal resistance of CNT-array-TIM was found to be 15 mm/sup 2/-K/W which was only 20% of that of the commercial silver epoxy. The mechanism of the phonon heat transfer through the CNT-array-TIM was reviewed. The application performance of CNT-array-TIM in HB-LED packages was predicted by finite element analysis using ANSYS code. It was concluded that CNT arrays synthesized by the simple thermal CVD procedure is a promising low cost and effective TIM.