Transparent conducting films on polymeric substrates are increasingly applied in diverse novel displays and flexible electronics. In this paper, indium tin oxide films on polymeric substrates were deposited by magnetron sputtering using ceramic targets with different doping ratios. These films were characterized by X-ray photoelectron spectroscopy, X-ray diffractometer, atomic force microscopy, spectroscopic ellipsometry, spectrophotometer, sheet resistance meter, and the Hall effect measurement. In terms of transparency and conductivity, the results have shown that the doping ratio played a less important role in determining the optical properties, while the electrical properties were significantly influenced. It was found that, when the thickness was less than 130 nm, these films with the nominal doping ratio of 95:5 (wt. %) demonstrated higher electrical conductivity compared to those with 90:10 (wt. %), which were widely used in industry. Therefore, for the flexible polymeric substrate, the target with a doping ratio of 95:5 (wt. %) could be suitable to achieve high electrical conductivity.

A batch of Sn oxides was fabricated by pulse direct current reactive magnetron sputtering (pDC−RMS) using different Ar/O₂ flow ratios at 0.3 Pa; the influence of stoichiometry on the physical and electrochemical properties of the films was evaluated by the characterization of scanning electron microscope (SEM), X-ray diffraction (XRD), X-ray reflection (XRR), X-ray photoelectron spectroscopy (XPS) and more. The results were as follows. First, the film surface transitioned from a particle morphology (roughness of 50.0 nm) to a smooth state (roughness of 3.7 nm) when Ar/O₂ flow ratios changed from 30/0 to 23/7; second, all SnO_x films were in an amorphous state, some samples deposited with low O₂ flow ratios (≤2 sccm) still included metallic Sn grains. Therefore, the stoichiometry of SnO_x calculated by XPS spectra increased linearly from SnO_0.0.08 to SnO_1.71 as the O₂ flow ratios increased, and the oxidation degree was further calibrated by the average valence method and SnO₂ standard material. Finally, the electrochemical performance was confirmed to be improved with the increase in oxidation degree (x) in SnO_x, and the SnO_1.71 film deposited with Ar/O₂ = 23/7 possessed the best cycle performance, reversible capacity of 396.1 mAh/g and a capacity retention ratio of 75.4% after 50 cycles at a constant current density of 44 μA/cm².