The isothermal crystallization process of amorphous indium tin oxide films was investigated by examining the peak intensity, obtained through high-temperature X-ray diffraction analysis The introduction of water vapor (5 x 10(-5) Torr) during sputtering-deposition significantly reduced the rate of crystallization This can be attributed to the presence of chemically bonded hydrogen Classical kinetic analysis based on the Kolmogorov Johnson Mehl Avrami equation indicated three distinct changes caused by the introduction of water vapor it reduced the kinetic exponent (n) from approximately 5/2 (2 59 +/- 0 12) to 3/2 (1 53 +/- 0 10). Increased the activation energy (E(a)) from 799 to 116 kJ/mol, and increased the average crystallite size from 54 to 93 nm Site-saturated and continuous nucleation models arc tentatively proposed, to account for the crystallization of amorphous ITO films deposited in the presence and absence of water vapor, respectively (C) 2009 Elsevier B V. All rights reserved.