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Carbon nanotube thermal interface material for high-brightness light-emitting-diode cooling.

Department of Mechanical Engineering, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, People's Republic of China.
Nanotechnology (Impact Factor: 3.67). 05/2008; 19(21):215706. DOI: 10.1088/0957-4484/19/21/215706
Source: PubMed

ABSTRACT Aligned carbon nanotube (CNT) arrays were fabricated from a multilayer catalyst configuration by microwave plasma-enhanced chemical vapor deposition (PECVD). The effects of the thickness and annealing of the aluminum layer on the CNT synthesis and thermal performance were investigated. An experimental study of thermal resistance across the CNT array interface using the modified ASTM D5470 standard was conducted. It was demonstrated that the CNT-thermal interface material (CNT-TIM) reduced the thermal interfacial resistance significantly compared with the state-of-art commercial TIM. The optimized thermal resistance of the CNT arrays is as low as 7 mm(2) K W(-1). The light performance of high-brightness light-emitting diode (HB-LED) packages using the aligned CNT-TIM was tested. The results indicated that the light output power was greatly improved with the use of the CNT-TIM. The usage of the CNT-TIM can be also extended to other microelectronics thermal management applications.

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