Carbon Nanotube Array Thermal Interfaces for High-Temperature Silicon Carbide Devices

Abstract

Multiwalled carbon nanotube (MWCNT) arrays have been directly synthesized from templated Fe₂O₃ nanoparticles on the C-face of 4H-SiC substrates by microwave plasma chemical vapor deposition (MPCVD), and the room-temperature thermal resistances of SiC-MWCNT-Ag interfaces at 69–345 kPa as well as the thermal resistances of SiC-MWCNT-Ag interfaces up to 250°C (at 69 kPa) have been measured using a photoacoustic technique. The SiC-MWCNT-Ag interfaces with MWCNTs grown on the C-face of SiC achieved thermal resistances less than 10 mm² K/W, which is lower than the resistances of MWCNT interfaces grown using the same catalysis and growth methods on the Si-face of SiC and Ti-coated SiC. The thermal resistances of the SiC-MWCNT-Ag interfaces exhibit weak temperature dependence in the measured range, indicating that the interfaces are suitable for high-temperature power electronics applications.

KEY WORDS:

• carbon nanotube
• thermal interface resistance
• silicon carbide
• high-temperature
• photoacoustic

We gratefully acknowledge funding from the Air Force Research Laboratory. B. A. Cola gratefully acknowledges fellowship support from the Intel Foundation and the Purdue University Graduate School.