Using Mono-, Bi- and Tri-Metallic Nanoparticles to Improve Selectivity and Sensitivity of CMOS-Integrated SnO2 Thin-Film Gas Sensors

We demonstrate the systematic optimization of SnO2-based thin-film chemical sensors by using mono-, bi- and tri metallic nanoparticles (NPs) composed of Ag, Pd, and Ru, which are deposited via magnetron sputtering inert gas condensation. The ultrathin SnO2 films are integrated on CMOS-based micro-hotplate devices, where each chip contains 16 sensor devices in total. We found that the response of the sensor device can be significantly tuned to specific target gases, such as CO and VOCs, by using various types of NPs.