Effect of microstructures on nanocrystallite nucleation and growth in hydrogenated amorphous indium–tin–oxide films

Hydrogenated amorphous indium–tin–oxide (ITO) films were prepared by a sputtering method at room temperature with H2O addition. The initial stage of thermal crystallization of the amorphous films was investigated after annealing at 150 °C, just below the crystallization temperature. With increasing H2O addition, the growth of crystallites dispersed in the amorphous matrix was suppressed, while the nucleation of crystallites was sharply enhanced. The amount of bonded hydrogen increased and that of oxygen vacancies decreased at the same time, with introducing inhomogeneites in the amorphous matrix. The effect of these microstructural changes on the nucleation and growth process of crystallites embedded in the amorphous solids was discussed based on these experimental results taking into account a recently proposed theoretical prediction to describe the crystallization of disordered solids.