Symposium EN07: Thermal Transport and Energy Conversion

Takahiro Baba, National Institute of Materials Science (NIMS), Japan

Thermal Diffusivity Measurement of Thin Films by Fourier Transform Thermo-Reflectance Method under Front Heat-Front Detect Configuration

Written by Kazi Zihan Hossain

Thermal conductivity measurement is crucial for nanoscale materials. In the traditional approach, thermal diffusivity is determined from an analytical solution after single pulse heating to obtain a thermos-reflectance signal; however, the actual thermos-reflectance signal requires periodic pulse heating. Takahiro Baba from the National Institute of Materials Science, Japan, and colleagues have developed a novel technique using the Fourier series to solve an exact analytical solution to express temperature response after heat diffusion from periodic pulse heating. A laser beam is incident on a 100-nm thick platinum thin film and collected with the photodetector when a pulse pump beam is used on the rear side of the thin film. The proposed technique could measure the thermal diffusivity and also exclude the effect of time delay. The technique is expected to work for more complicated samples like multi-layered thin films.