Thermal crystallization kinetics and crystallite size distribution of amorphous ITO film deposited in the presence or absence of water vapor

Abstract

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 × 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 79.9 to 116 kJ/mol, and increased the average crystallite size from 54 to 93 nm. Site-saturated and continuous nucleation models are tentatively proposed, to account for the crystallization of amorphous ITO films deposited in the presence and absence of water vapor, respectively.