Thermophysical properties of thin films on substrate

In the analysis of thermophysical properties in a thin film, it is important to take into account those in the interfacial region between a thin film and a substrate on which the film was grown. In order to analyze them, an ac calorimetric thermal diffusivity measurement is very useful. In this measurement, the thermal diffusivity of the component parallel to the surface of a thin film is obtained as a function of film thickness for a single film and also as a function of layer thickness for a superlattice. In the present paper, an analytical method is proposed and it is applied to the analysis of thermophysical properties in diamond films and in AlAs/GaAs superlattices.