Gas sensing properties of metal doped WO3 thin film sensors prepared by pulsed laser deposition and DC sputtering process

Tungsten trioxide (WO3) thin films gas sensors were prepared by the KrF excimer pulsed laser deposition (PLD) method. The films were prepared on the quartz glass, silicon and also on the Al2O3 sensor substrates with platinum interdigitated thin film was also investigated. electrodes. The effect of doping of the platinum (Pt), palladium (Pd) or gold (Au) on the WO3 thin film was also investigated. These metals were doped to the W03 thin film by the DC sputtering process during the PLD. The substrate temperature and the oxygen pressure were 400 degrees C and 100 mTorr, respectively, during the deposition. The films were characterized by atomic force microscopy (AFM) and X-ray diffraction (XRD). The sensitivity of the prepared sensors to 60 ppm NO gas was examined using the two terminal resistance method in a chamber at atmospheric pressure and operating temperatures of 350 degrees C. The sensitivity of the WO3 thin films doped with Pt, Pd, or An was found to be higher than that of the undoped WO3 thin film.