Among the commercially common transparent conducting oxides (TCOs) are fluorine-doped tin oxide (FTO) and indium-doped tin oxide (ITO), neither of which meets all criteria for the optimal TCO. Despite its superior chemical stability and being composed of abundant elements, FTO suffers from high surface roughness compared to ITO. Here, we introduce a path to substantially decrease the surface roughness of FTO, while preserving most of its original advantages, by depositing an SnO2 coating on top of the FTO layer using pulsed laser deposition. Such an enhancement may allow future use of FTO in devices that use now the more expensive, less stable ITO, which contains relatively rare indium.
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The authors thank Dr. Olga Girshevitz and Dr. Eti Teblum for their kind assistance with the AFM measurements and analyses, and Ben Kayser for his help with the resistivity measurements.
D.A.K acknowledges the Israeli Ministry of Science, Technology, and Space for their financial support (project 204428). This project has received funding from the Israel Science Foundation (grant 1729/15) and the Israeli National Nanotechnology Initiative (INNI, FTA project).
Conflicts of Interest
There are no conflicts of interest to declare.
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Keller, D.A., Barad, HN., Rosh-Hodesh, E. et al. Can fluorine-doped tin Oxide, FTO, be more like indium-doped tin oxide, ITO? Reducing FTO surface roughness by introducing additional SnO2 coating. MRS Communications 8, 1358–1362 (2018). https://doi.org/10.1557/mrc.2018.179