Ruthenium oxide cryogenic temperature sensors

RuO2 based cryogenic temperature sensors were developed using a nanopowder approach. Ruthenium oxide nanopowders were consolidated into compacts using the Plasma Pressure Compaction (P2C®) process and were tested for resistivity as a function of temperature for determining the reproducibility and stability of the sensors due to thermal stresses. The sensors showed metallic behavior and strong positive temperature coefficient of resistivity (PTCR). Resistance–temperature calibration demonstrated a monotonic response with a positive temperature coefficient of resistivity from 70 to 300 K along with dimensionless sensitivity (approximately 1.0) comparable to that of platinum resistance thermometers.