Tailore Ruthenium Oxide Films for Mems Cryogenice Thermometry with Record Sensitivity Below 10K

This work presents a cryogenic temperature sensor fabricated using a self-prepared ruthenium oxide (RuO 2) slurry rather than conventional commercial pastes. The tailored formulation enables precise control over microstructure and conduction pathways, resulting in markedly enhanced sensitivity and stability at deepcryogenic temperatures. At 1 K, the sensor achieves a sensitivity of$1769 \Omega/\mathrm{K}$, which is over five times that of the widely used RX-102B-RS ($316 \Omega/\mathrm{K}$) along with a significantly higher TCR of 0.0837/K compared to 0.0497 /K, a significantly higher Sa of 0.1284 compared to 0.0517. These results show that integrating optimized slurry chemistry with MEMS-compatible processing sets a new benchmark in cryogenic sensing and enables a scalable route to reproducible, high-performance devices for lowtemperature applications.