Chemically-driven control of electrical resistivity of high-entropy alloys

• Ag, Al, Cu and Zr have been added into Cantor thin films deposited by magnetron sputtering. • The microstructure of the films is strongly dependent on the nature of the added element. • The electrical resistivity, measured in the 80 – 350 K range, can be tuned by the concentration of the sixth element. • The temperature coefficient of resistance (TCR) can be tuned from 355 to −480 ppm/K. • CrMnFeCoNiCu37 thin film exhibit a TCR value close to 0. Chemical control of electrical properties in high-entropy alloys (HEAs) remains largely unexplored despite their potential for next-generation electronic devices. Herein, we demonstrate unprecedented tuning of electrical characteristics in CrMnFeCoNi thin films by systematically incorporating elements with distinct metallic radii (Cu, Al, Ag, and Zr). Comprehensive structural analysis reveals composition-dependent phase evolution: Cu maintains a face-centered cubic (fcc) structure with reduced nanotwins, Al induces fcc-to-bcc transition, Zr drives amorphization, and Ag forms distinctive nanoprecipitates. Through these targeted chemical modifications, we achieve a remarkable resistivity range of 89–324 μΩ·cm and exceptional TCR control, including a near-zero value of -2.86 ppm/K in CrMnFeCoNiCu37 that outperforms conventional low-TCR alloys like Constantan and Manganin. This chemically-driven approach enables remarkable TCR tunability from +355 to -480 ppm/K, establishing HEAs as promising candidates for sustainable thermocouple devices and integrated circuits, offering superior performance and scalability compared to traditional materials.