An Improved Dynamical Method for Thermal Conductivity and Specific Heat Measurements of Thin Films in the 100 nm-Range

We report on a new experimental technique based on a modified 3ω method that combines two existing techniques. The configuration is insensitive to temperature fluctuations and shows negligible radiation losses. It allows a simultaneous measurement of the thermal conductivity and the specific heat of thin films between 1 K < T < 400 K with high accuracy and reproducibility. A self supporting membrane is used as the substrate. First results demonstrating the applicability of the new technique are presented.