Design of Low Cost Gas Sensor Based on SrTiO3 and BaTiO3 Films

SATREERAT K. HODAK; THIDARAT SUPASAI; ANURAT WISITSORAAT; JOSE H. HODAK

Journal of Nanoscience and Nanotechnology

Año: 2010

We have prepared SrTiO3/BaTiO3 multilayer film on alumina substrates by a sol–gel technique andinvestigated their response for sensing ethanol vapor. The surface morphology of the films werecharacterized by atomic force microscope (AFM) showing that the grain size of the films increaseup to 40 nm as the annealing temperature increased to 1000 C. The ethanol sensors based onSrTiO3/BaTiO3 thin films were fabricated by applying interdigitated gold electrodes by sputteringtechnique. The ethanol sensing characteristics of SrTiO3/BaTiO3 thin films were quantified by thechange in resistance of the sensors when they were exposed to ethanol. The optimum operatingtempearature of these sensors was found to be 350 C. In addition, the film annealed at 1000 Cexhibited p-type gas sensing behavior with the best sensitivity of 30–100 for low ethanol concentrationin the range of 100–1000 ppm.