Abstract
In this paper, we report on investigation concerning the substrate-dependent thermal conductivity (k) of Aluminum Nitride (AlN) thin-films processed at low temperature by reactive magnetron sputtering. The thermal conductivity of AlN films grown at low temperature (<200 degrees C) on single-crystal silicon (Si) and amorphous silicon nitride (SiN) with thicknesses ranging from 100 nm to 4000 nm was measured with the transient hot-strip technique. The k values for AlN films on SiN were found significantly lower than those on Silicon consistently with their microstructures revealed by X-ray diffraction, high resolution scanning electron microscopy, and transmission electron microscopy. The change in k was due to the thermal boundary resistance found to be equal to 10 x 10(-9) Km(2)W(-1) on SiN against 3.5 x 10(-9) Km(2) W-1 on Si. However, the intrinsic thermal conductivity was determined with a value as high as 200 Wm(-1) K-1 whatever the substrate. (c) 2014 AIP Publishing LLC.