Water-assisted crystallization of amorphous indium zinc oxide films

Indium-zinc-oxide thin films produced by low-cost chemical solution deposition: Tuning the microstructure, optical and electrical properties with the processing conditions

“…Interestingly, the R s value of IZO7, for which the distinct layers were not observed, is an order of magnitude larger than that of IZO6, although its thickness is similar to that of IZO6. We attribute this observation to the fact that IZO7 contains larger grains that perturb the matrix phase and contribute to a lower carrier mobility, which is consistent with Steigert et al [ 14 ], who found that after crystallization, the films with larger grains have higher resistivities than the films with smaller grains.…”

“…The IZO thin films were found to be n-type semiconductors with oxygen vacancies ( o ), interstitial Zn ( n i ), and indium on zinc (In zn ·) as the source of donors. The type and amount of defects and their mobility in the thin films are influenced not only by the chemical composition, but also by factors such as the deposition conditions, post-deposition curing, crystal structure, thickness, and microstructure of the film [ 9 , [12] , [13] , [14] , [15] ]. For example, Tsai et al [ 12 ] suggested that the high resistivity of amorphous IZO thin films with very low thicknesses could be related to the large strain and defect homogenization in the layer.…”

Thermal Stability of Amorphous Metal Oxides: The Interplay of Secondary Cations, Degree of Substitution, and Local Structure

“…A similar trend is observed for the IZO case except that the relation becomes more exponential and crystallization temperatures T c are 223, 279, 421, and 605 °C for x from 5 to 30%, respectively. Similar results (∼520 °C) were obtained in ∼20% Zn-substituted IZO film . This also suggests that at a lower degree of substitution (5 and 10%), Sn and Zn exhibit a similar capability to maintain an amorphous structure, while at a higher substitution level (20 and 30%), the introduction of Zn leads to a much more thermally stable amorphous phase compared to Sn.…”

“…Similar results (∼520 °C) were obtained in ∼20% Zn-substituted IZO film. 33 This also suggests that at a lower degree of substitution (5 and 10%), Sn and Zn exhibit a similar capability to maintain an amorphous structure, while at a higher substitution level (20 and 30%), the introduction of Zn leads to a much more thermally stable amorphous phase compared to Sn. For IGO, at a low degree of substitution (5 or 10%), the crystallization has a comparable or slightly higher T c (257 and 302 °C).…”

“…Despite the increasing research activity on AMOs, little is known about their thermal stability in maintaining the amorphous phase when subjected to external thermal treatments, which, for example, would be involved in device fabrication processes and some applications. The increasing interest in AMOs over their crystalline counterparts has stimulated extensive efforts to synthesize as-deposited amorphous films, while less attention has been paid to stabilizing the amorphous phase. − Hence, whether the initially deposited AMO layer undergoes structural changes is critical to the device’s performance. A clear understanding of the thermal stability of as-deposited AMO films is thus of great importance in preventing the formation of crystalline phases and maintaining consistent microstructures throughout the entire manufacturing process.…”