Low temperature preparation of YSZ-based thin-film limiting current type oxygen sensor

Oxygen sensors based on YSZ solid electrolyte thin films have great application prospects due to their advantages in miniaturization and integration. Here, we report the gas sensing performance of Pt/YSZ/Pt oxygen gas sensors with low preparing temperatures. YSZ thin films with (200) preferred orientation have been prepared by room temperature RF magnetron sputtering combined with annealing at a temperature of 650 °C. The 700 nm-thick YSZ films exhibit an obvious limiting current platform, and the limiting current I_L shows a linear dependence on oxygen concentration X(O₂) (in the range of 6%–21%). Moreover, the devices with 700 nm-thick YSZ films worked well at the temperature range from 500 to 650 °C, and a linear relationship between logI_L and 1000/T has been observed. These results demonstrate that YSZ thin films prepared by low temperature magnetron sputtering combined with the annealing process can reduce the working temperature.