Optimization of Sample Preparation and Characterization of Thin Films on a Guarded Heat Flow Meter

Abstract

The application of Thermal Interface Materials (TIMs) and the resulting thermal resistance properties can have a significant effect on the results of Thermal Conductivity measurements, specifically when testing materials with low thermal resistances or multi-layer thin-films. The thermal resistance of the TIM can be characterized by measuring the same reference material which has been sequentially split into multiple segments while maintaining the same overall thickness. This results in a sequential increase of the measured thermal resistance as the number of interfaces where TIM is applied increases. This proposed calibration method allows for the generation of an offset curve which can exclude the effect of TIMs in both single sample measurements and multi-layer thin film sample measurements, which results in decreased test to test variability and increased measurement accuracy.