Abstract
A detailed experimental and theoretical study on the local (r ≤ 4.5 Å) atomic structure of amorphous and crystalline zinc-indium-tin oxide (ZITO) thin films using grazing-incidence x-ray Pair-Distribution Functions (PDFs), ab initio Molecular Dynamics (MD), and Empirical Potential Structure Refinement (EPSR) Monte Carlo simulations is presented. High-energy synchrotron x rays, a two-dimensional detector, and different incident angles were used to probe the depth uniformity of five (ZnO)0.15 (In2O3)0.70 (SnO2)0.15 films that were deposited via pulsed-laser deposition at growth temperatures (TG) ranging from 25 to 300 °C. Films deposited at TG ≤ 150 °C were amorphous. The partially crystalline (TG = 200 °C) and fully crystalline (TG = 300 °C) films were highly textured. Both crystalline and amorphous structures were investigated using ab initio MD and EPSR Monte Carlo simulations. The density of the amorphous films determined from the experimental data agreed with MD calculations. Coordination numbers, bond lengths, and distortion for metal-oxygen and for both the edge- and corner-shared In-metal shells up to 4.5 Å obtained from PDF analysis closely agreed with MD and EPSR simulations. There is a pronounced decrease in the edge- and corner-shared In-Zn distances arising from the shorter Zn-O bond length, Zn-O tetrahedral coordination, and In-O-Zn angle in amorphous ZITO compared to its crystalline counterpart. A maximum in electrical mobility was observed for the amorphous film just before crystallization occurred. While the peak is broad, consistent with nearly unchanged overall cation-oxygen coordination in the amorphous films, ESPR results indicate that the tetrahedral coordination follows the conductivity trend.
Recommended Citation
G. B. González and C. J. Benmore and J. E. Medvedeva and J. S. Okasinski and C. Riegger and O. Medina and M. M. Stulajter and T. Bsaibes and G. Cardenas and S. Cone and K. Edlund and M. Osorio and T. Holmes and I. Zhuravlev, "Local Structure Of Zinc-indium-tin Oxide Films Via Grazing-incidence X-ray Pair-distribution Functions And Theoretical Methods," Journal of Applied Physics, vol. 137, no. 11, article no. 115104, American Institute of Physics, Mar 2025.
The definitive version is available at https://doi.org/10.1063/5.0246132
Department(s)
Physics
Publication Status
Open Access
International Standard Serial Number (ISSN)
1089-7550; 0021-8979
Document Type
Article - Journal
Document Version
Final Version
File Type
text
Language(s)
English
Rights
© 2025 American Institute of Physics, All rights reserved.
Publication Date
21 Mar 2025
Comments
Missouri University of Science and Technology, Grant DMR-1842467