Nanoscale Insights into Thermoelectric Electrode Interfaces Using Kelvin Probe Force Microscopy

Kurzfassung

High interfacial resistance at metal–thermoelectric (TE) contacts causes significant power loss, yet its origins—such as Schottky barriers, microcracks, or interfacial layers—are not well understood. Traditional Potential Seebeck microprobe measurements are limited by contact constraints and hence limited resolution in micron. In contrast, Kelvin Probe Force Microscopy (KPFM) offers a powerful non-contact approach with nanometer-scale spatial resolution, making it highly suitable for probing interfacial potential variations. We present robust sample preparation for KPFM analysis of TE–electrode interfaces and report initial findings of a distinct contact potential difference (CPD) drop near the electrode. These observations are supported by local Seebeck measurements and multiband modeling, demonstrating KPFM’s potential to reveal interfacial phenomena critical for reducing contact resistance in thermoelectric devices.