Molybdenum-doped indium oxide In2O3:Mo (IMO) thin films were deposited on glass substrates by a technique called channel spark ablation. The structure, surface morphology, electrical, and optical properties of these films were investigated by x-ray diffraction, atomic force microscopy (AFM), four-point probe, ultraviolet photoelectron spectroscopy (UPS), Hall analysis, and spectrophotometry. The influence of oxygen pressure on the electrical properties of IMO thin films prepared at T-s=350 degrees C was studied, showing that increasing oxygen pressure changes the resistivity concavely and the carrier concentration convexly. The IMO films as deposited are well crystallized with a preferred orientation of (222) and the surface roughness evaluated in terms of Rrms, Ra, and Rp-v measured by AFM is 0.72, 0.44, and 15.4 nm, respectively. The lowest resistivity and corresponding carrier concentration are 4.8 X 10(-4) Omega cm and 7.1 X 10(20) cm(-3). The typical work function of IMO is 4.6 eV measured by UPS. For all the samples, the average transmittance in the visible region is more than 87%. (c) 2005 American Vacuum Society.