Improved ZnO based materials for to-date flat panel displays

Promising approaches to improve electrical characteristics, chemical resistance, and thermal stability of the resistivity of ZnO-based TCO thin films are investigated. The following ways were tested: A) gradient doping of ZnO grains into the synthesized TCO films by indium in order to create passivating coatings on the surface of the grains; b) preventing the oxygen diffusion into the films by suppressing the columnar structures formation; c) methods combining the above ones. It was found that in the ZnO-based TCO films deposited by magnetron sputtering at temperature above 150°C under the presence of excess zinc in the reagent flow, a decrease in the porosity of the columnar ZnO films is observed after subsequent heat treatments in air. The introducing of In, Ga, Sn metals to the composition of the ZnO films contributes to the formation of thin surface oxide sub-layers with passivation properties on the surface of the ZnO grains. The results of research clearly show that preventing the formation of a columnar structure in combination with the passivation of grain surfaces creates real prospects for expanding the areas of application of ZnO-based transparent electrodes. © 2019 SID-the Society for Information Display. All rights reserved.