Thermal conductance of silicon interfaces directly bonded by room-temperature surface activation

Using the recently developed method to directly measure thermal boundary conductance (TBC) across bonded interfaces, we report the measurements of TBC at interfaces bonded by surface activated bonding at room temperature. The TBC of as-bonded silicon-silicon interface is limited to 1.3 x 10(2) MW m(-2) K-1, which is equivalent to thermal conductance of micrometer-thick bulk silicon. We further show that the TBC can be greatly improved by recrystallizing the amorphous interlayer, which here is realized by thermal annealing. The dependence of the TBC on the annealing temperature is highly nonlinear, which can be explained in terms of thermal activation of crystal growth. (C) 2015 AIP Publishing LLC.