Pure and Mo-doped SnO2 films were deposited on the glass substrates by sputtering from the metallic Sn and Mo targets with subsequent annealing in air at various temperatures from 500 to 700 degrees C. The properties of the grown films were studied for gas sensor applications. The optimum annealing temperature was 500 degrees C. The pure and the doped films annealed at this temperature showed best sensitivities for both alcohol and amine gases. While there was no distinct difference between the pure and the Mo-doped films for the alcohol gases at the operating temperature of 400 degrees C, the latter showed clearly improved sensitivities at lower temperature (300 degrees C), e.g., the ethanol sensitivity of SnO2:Mo was 16.47 and 7.97 at 400 and 300 degrees C, respectively, compared to 14.77 and 2.92 for the pure SnO2. However, the SnO2:Mo films responded much more sensitively to the amine gases than pure SnO2 films. With the optimum Mo content of 7.3 atom %, the doped films showed a sensitivity of as high as 29.49 for hydrazine. (C) 2010 The Electrochemical Society. [DOI: 10.1149/1.3391899] All rights reserved.