Development and digital twin of an experimental opto-electrothermal bench in the perspective of thin films thermal characterization

Abstract

This work aims to widen the application of the front Flash methods to dielectric materials with thermal conduction times ranging from seconds to a few tens of nanoseconds. In this perspective, the design and characteristics of an experimental opto-electrothermal bench are presented here: its principle is based on the Flash methods (short optical excitation) however combined with an electrothermal measurement. The development of direct models acting as digital twins of the bench is also described. They allow considering its electrothermal behaviour, by taking into account the 1D thermal diffusion in a multilayer sample and the non-ideal frequency response of the acquisition chain (signal conditioner and the measuring devices) according to the sample thermal dynamics – which is little discussed in the literature to the authors’ knowledge. The methodology proposed here for the sizing and consideration of the acquisition chain can be applied to other electrothermal measurements methods such as the 3ω methods.