Dynamical thermal model for thin metallic film–substrate system with resistive heating

Abstract

In this paper the dynamical thermal behavior of the thin metallic film–substrate system is theoretically and experimentally discussed. The thin film–substrate system is considered as a bimaterial and the heat source used is the Joule effect on the metallic film when an electrical current is applied through the film. In order to obtain a physical picture of the temporal distribution of temperature on the film and substrate, a dynamic thermal model is proposed. This model has the feasibility to predict the temperature profile on the film and substrate, and to describe the dependence of geometrical, environmental, and material parameters of the system, on its thermal response. Experimental measurements on gold/glass and Al/Si(100) systems were performed and compared with the proposed model. The bimaterial thermal model proposed reproduces our experimental results with high accuracy. The model can be readily extended to study any kind of bimaterial system. The model is also appropriate to study multilayer thin film solar cells and to estimate thermal conditions on microelectromechanic (MEM) devices.