Importance of Schottky barriers for wide-bandgap thermoelectric devices

TL;DR

This paper highlights the critical impact of Schottky barriers on the efficiency of wide-bandgap thermoelectric devices and proposes a simple contact solution to mitigate this issue.

Contribution

It reveals the significance of Schottky barriers in thermoelectric device performance and suggests a practical fix to improve efficiency.

Findings

Schottky barriers can significantly reduce thermoelectric efficiency.

A two-metals contact solution can effectively mitigate Schottky barrier effects.

Understanding barriers enables cost-effective device optimization.

Abstract

The development of thermoelectric devices faces not only the challenge of optimizing the Seebeck coefficient, the electrical and thermal conductivity of the active material, but also further bottlenecks when going from the thermoelectric material to an actual device, e.g., the dopant diffusion at the hot contact. We show that for large bandgap thermoelectrics another aspect can dramatically reduce the efficiency of the device: the formation of Schottky barriers. Understanding the effect, it can then be fixed rather cheaply by a two-metals contact solution.