Some Thermoelectric Characteristics of Si0.95Ge0.05 Alloy and Monolithic Module Performance

Abstract

Si-Ge alloys serve as benchmark materials for high-temperature thermoelectric generators, particularly in aerospace power systems. To lower fabrication costs and expand terrestrial applications, reducing the Germanium content while maintaining competitive conversion efficiency remains a critical engineering objective. In this work, we investigate the high-temperature thermoelectric characteristics of a low-Ge content alloy, Si0.95Ge0.05. The transport metrics, the temperature-dependent trajectories of the electronic quality factor (BE) and the thermoelectric compatibility factor (CF) are analyzed to elucidate underlying charge carrier scattering and system segmentation viability. Furthermore, the material parameter (B) and generalized material parameter (B*) are calculated to predict the upper bounds of the dimensionless the gap between material properties and practical device-level implementation, monolithic thermoelectric generator modules with 16 and 24 branches were fabricated using vacuum induction hot pressing. The 24-branch module achieved a peak power output of 2.25 W and a practical thermal-to-electrical energy conversion efficiency of 9.2% under a hot-junction temperature of 480 °C, establishing a highly competitive benchmark for low-Ge thermoelectric systems.