Preparation and Characterization of TE Interfaces/Junctions

Abstract

The existence of various contact layers and interfaces between the layers will inevitably introduce both electrical and thermal contact resistances into a practical thermoelectric device. In order to minimize the performance reduction due to the contact resistances of the interfaces, preparation and characterization of thermoelectric junction/interfaces become an important prerequisite for thermoelectric module fabrication. This chapter provides a brief overview on the basic principles and the state-of-the-art technologies that are crucial to achieving low-contact resistances for the fabrication of high-performance thermoelectric devices. A simplified model is developed to describe the influence of electrical and thermal contact resistances on the performance of thermoelectric devices and provide a quantitative evaluation of the contact resistance required for satisfactory manufacturing of thermoelectric modules. The chapter further describes the technique for characterization of electrical contact resistance based on a scanning resistance probe, together with experimental results to demonstrate the usefulness and capability of the equipment.