In-plane thermal conductivity of nanoscale polyaniline thin films

Thermal characterization of conducting polymers is important in understanding transport phenomena in energy conversion and flexible electronics devices. We present an experimental technique to determine the in-plane thermal conductivity and the thermal contact resistance of thin films on substrates simultaneously. For 20 nm thick polyaniline films on SiO₂ substrate, the respective values were measured to be 0.0406 W/m K and 0.806 K m² /W. We also observed thickness dependence of in-plane thermal conductivity, which suggests that heat transfer is governed by phonon-boundary scattering when the film thickness is close to the mean free path.