Investigation of sol-gel prepared CeO2-TiO2 thin films for oxygen gas sensing

The oxygen gas sensing performance of semiconducting CeO2 - TiO2 thin films have been investigated. These thin films have been prepared by the sol-gel process utilizing a non-alkoxide as the main precursors. For gas sensing measurements, the films were deposited by the spin coating technique onto alumina substrates with interdigital transducers located on the top and a micro-heater on the bottom. For the microstructural characterization, the thin films were deposited onto single crystal silicon substrates. X-ray Photoelectron Spectroscopy (XPS), Auger Electron Spectroscopy (AES) and Scanning Electron Microscopy (SEM) were employed in order to analyze the films. These films were exposed to various concentrations of O2 gas and their electrical responses were measured.