Here, the authors present an improved transparent conducting thin film by adding multi‐wall carbon nanotube (MWCNT) to fluorine tin oxide (FTO). The use of carbon nanotubes considerably increases the surface conductivity of the FTO thin film. The resulting composition is deposited on a Pyrex substrate by the spray pyrolysis technique. Measurement results show high optical transmittance (about 77%) in the visible region and low electrical surface resistance (as low as 5 Ω/◻). The electromagnetic characteristics of the resulting layer false(σ,εrfalse) are obtained over 0.1–20 GHz using the open‐ended coaxial probe (OECP) method. The conductivity (σ) is in the order of 105false(S/mfalse) and relative permittivity false(εrfalse) is in the order of 106 at low frequencies and in the order of 105 at high frequencies, which is suitable for transparent antenna applications. To verify the measurements, the layer is numerically simulated using the obtained experimental data. The simulation results were found to be in good agreement with the experimental ones.

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An efficient method to determine the electromagnetic characteristics of transparent conducting oxide (TCO) thin films is presented herein. When a two-port flange coaxial probe is used for electromagnetic characterization, it is important to note that since the thickness of the film is very thin, it should be taken into account that the measured S parameters not only correspond to the thin film, but also to the substrate. The main idea of this study is to exploit the S parameters corresponding solely to the thin film by employing transfer matrix method. Then, by using the obtained S parameters, the effective conductivity (σ) and relative permittivity (ε r) of the TCO thin film are determined. By applying this method to a sample under test, the conductivity and relative permittivity are obtained in the order of 10 5 (S/m) and 10 6 in the 2-20 GHz frequency range, respectively. These results are compared with those obtained by the Nicolson-Ross-Wier and open-ended coaxial probe methods. Simulation results show that when the TCO thin film thickness reaches 0.5 mm, its conductivity increases up to two times. Also, when the gap between the coaxial probe and the thin-film surface is 0.1 mm, the conductivity approaches zero. Using this method, the material and thickness of the substrate have slight effect on determining the electromagnetic characteristics. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.