Substrate effects on the oxygen gas sensing properties of SnO2/TiO2 thin films

Abstract In this study, SnO 2 /TiO 2 thin films are fabricated on SiO 2 /Si and Corning glass 1737 substrates using a R.F. magnetron sputtering process. The gas sensing properties of these films under an oxygen atmosphere with and without UV irradiation are carefully examined. The surface structure, morphology, optical transmission characteristics, and chemical compositions of the films are analyzed by atomic force microscopy, scanning electron microscopy and PL spectrometry. It is found that the oxygen sensitivity of the films deposited on Corning glass 1737 substrates is significantly lower than that of the films grown on SiO 2 /Si substrates. Therefore, the results suggest that SiO 2 /Si is an appropriate substrate material for oxygen gas sensors fabricated using thin SnO 2 /TiO 2 films.

[1]  J. S. Lees,et al.  A structural investigation of titanium dioxide photocatalysts , 1991 .

[2]  N. Tohge,et al.  A Patterned-TiO 2 /SnO 2 Bilayer Type Photocatalyst , 2000 .

[3]  Sensing mechanism of SnO2-based sensors for alcohols , 1993 .

[4]  Soon-Don Choi,et al.  SnO2 thin film gas sensor fabricated by ion beam deposition , 2004 .

[5]  D. Vlachos,et al.  The effect of film oxygen content on SnOitx gas-sensor selectivity , 1995 .

[6]  Marco Faccio,et al.  Cross sensitivity and stability of NO2 sensors from WO3 thin film , 1996 .

[7]  Makoto Egashira,et al.  High H2 sensing performance of anodically oxidized TiO2 film contacted with Pd , 2002 .

[8]  K. Ihokura,et al.  The Stannic Oxide Gas SensorPrinciples and Applications , 1994 .

[9]  M. Graetzel,et al.  Energy Resources through Photochemistry and Catalysis , 1983 .

[10]  P. Siciliano,et al.  Microstructural characterization of MoO3–TiO2 nanocomposite thin films for gas sensing , 2001 .

[11]  Z. G. Liu,et al.  Comparative study of laser ablation techniques for fabricating nanocrystalline SnO2 thin films for sensors , 1996 .

[12]  Giorgio Sberveglieri,et al.  Recent developments in semiconducting thin-film gas sensors , 1995 .

[13]  K. Hashimoto,et al.  Photocatalytic efficiency of TiO2/SnO2 thin film stacks prepared by DC magnetron sputtering , 2004 .

[14]  U. Lampe,et al.  Metal Oxide Sensors , 1995, International Conference on Solid-State Sensors, Actuators and Microsystems.

[15]  W. Tai.  Photoelectrochemical properties of SnO2/TiO2 coupled electrode sensitized by a mercurochrome dye , 2001 .

[16]  R. P. Gupta,et al.  Influence of oxidation temperature, film thickness and substrate on NO2 sensing of SnO2 ultra thin films , 2002 .

[17]  Liyi Shi,et al.  Morphology and properties of ultrafine SnO2-TiO2 coupled semiconductor particles , 2000 .

[18]  W. Yao,et al.  Structure and photocatalytic performances of glass/SnO2/TiO2 interface composite film , 2004 .

[19]  Kôzô Inoue,et al.  Ruthenium dye-sensitized SnO2/TiO2 coupled solar cells , 2002 .

[20]  Sibudjing Kawi,et al.  High-surface-area SnO2 : a novel semiconductor-oxide gas sensor , 1998 .

[21]  Ki Chang Song,et al.  Preparation of high surface area tin oxide powders by a homogeneous precipitation method , 2000 .

[22]  W. Tai.  Photoelectrochemical properties of ruthenium dye-sensitized nanocrystalline SnO2:TiO2 solar cells , 2003 .

[23]  Soon-Don Choi,et al.  Undoped and 0.1 wt.% Ca-doped Pt-catalyzed SnO 2 sensors for CH 4 detection , 2005 .

[24]  Hsiao-Ching Lee,et al.  Effects of O2/Ar flow ratio on the alcohol sensitivity of tin oxide film , 2006 .

[25]  Pietro Siciliano,et al.  SnO2 thin films for gas sensor prepared by r.f. reactive sputtering , 1995 .

[26]  Jeffrey M. Gordon,et al.  Solar energy engineering , 2001 .

[27]  A new model and gas sensitivity of non-equilibrium xSnO2-(1–x)α-Fe2O3 nanopowders prepared by mechanical alloying , 1998 .

[28]  Xujie Yang,et al.  RAPID SYNTHESIS OF NANOCRYSTALLINE TIO2/SNO2 BINARY OXIDES AND THEIR PHOTOINDUCED DECOMPOSITION OF METHYL ORANGE , 2002 .