Thermal Properties of Metallic Films at Room Conditions by the Heating Slope

An analytical model and a methodology for determining the thermal diffusivity and the thermal conductivity of metallic thin films at room conditions are proposed. The analytical model is based on the one-dimensional heat transfer equation, which allows estimation of the thermal conductivity and thermal diffusivity through the initial heating slope value. The thermal conductivity and thermal diffusivity values of gold and aluminum films from 20 to 200 nm thicknesses, determined from the initial slope of the measured heating profiles, and their comparison with the analytical ones are discussed. Results show that thermal diffusivity increases from (30 +/- 6) x 10(-6) m(2)/s to (127 +/- 12) x 10(-6) m(2)/s for gold films, and it increases from (15 +/- 7) x 10(-6) m(2)/s to (95 +/- 10) x 10(-6) m(2)/s for aluminum films; although thermal conductivity increases from (132 +/- 35) to (306 +/- 48) W/m . K for gold films and from (58 +/- 30) to (243 +/- 39) W/m . K for aluminum films, when the film thickness increases.