GAS SENSING PROPERTIES OF RUTILE-TiO2 (100) FILMS PREPARED BY PULSED LASER DEPOSITION

Gas sensing property of TiO2 thin films have been demonstrated in rutile-TiO2 (100) films grown on the a-Al2O3 (0001) substrates by Pulsed Laser Deposition (PLD). High quality rutile-TiO2 (100) films were successfully grown on a-Al2O3 (0001) with the substrate temperature at 500oC under 15 mTorr of O2 gas pressure. The thickness and crystallinity of TiO2 films were evaluated by Rutherford backscattering spectrometry combined with channeling (RBS/C) and X-ray diffraction using q-2q scans. To evaluate CO2 gas sensing property of TiO2 films, the dependence of the changing of electrical resistivity on the temperature was measured. It’s found that high crystallinity rutile-TiO2 (100) films on the a-Al2O3 (0001) substrate kept at 100oC exhibits good gas sensing property for CO2 gas.

Keywords: X-ray diffraction, laser epitaxial, TiO2 thin film, electrical resistivity, CO2