High temperature thermal properties of thin tantalum nitride films.

Tantalum Nitride (TaN) films carry high heat fluxes in a variety of applications including diffusion barriers in magnetoresistive random access memory and buffer/absorbers in extreme ultraviolet masks. The thicknesses of these films are usually of the same order as the thermal energy carrier mean free path, which complicates the study of heat conduction. This paper presents thermal (cross-plane) and electrical (in-plane) conductivity measurements on TaN films with thicknesses of 50, 75, and 100 nm. Picosecond thermoreflectance is used to extract the thermal boundary resistance between TaN and Al and the intrinsic thermal conductivity of TaN for temperatures of 300-700 K. The data and the relative importance of boundary resistances, electron-boundary scattering, and electron-defect scattering are interpreted using the electrical and thermal transport data. These data facilitate comparison of the phonon and electron contributions to thermal conduction in TaN. [ABSTRACT FROM AUTHOR]