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Achieving high-efficiency optoelectronic devices often requires the development of high transparency in the extended range and high-conductivity materials, which can be ensured by the high mobility of charge carriers being used as the electrode. Among the candidate materials, transparent conductive indium zinc oxide (IZO) has attracted significant interest because of its superior electron mobility (5−60 cm2/V·s) and the thermal stability of its structure. In this study, the IZO films were deposited by the radio frequency magnetron sputtering of the IZO ceramic target (containing 10 wt.% ZnO) by varying the two variables of the substrate temperature and the oxygen content in the working gas. Here, the importance of the deposition of the IZO films at a low substrate temperature, not exceeding 100 °C, in order to get the minimum values of the film resistivity is revealed. At a substrate temperature of 100 °C, the film deposited in pure argon demonstrated a minimum resistance of 3.4×10−4 Ω·cm. Despite the fact that, with the addition of O2 in the working gas, an increase in resistivity was observed, the IZO film that deposited under 0.4% O2 content demonstrated the highest mobility (μ = 35 cm2/V·s at ρ = 6.0 × 10−4 Ω·cm) and enhanced transparency in the visible (VIS, 400−800 nm) and near-infrared (NIR, 800−1250 nm) ranges (TVIS ≥ 77% and TNIR ≥ 76%). At an oxygen content above 0.4%, a significant deterioration in electrical properties and a decrease in optical characteristics were observed. SEM and XRD studies of the microstructure of the IZO films allowed the clarification of the effect of both the substrate temperature and the oxygen content on the functional characteristics of the transparent conducting IZO films.

The aim of this work is preparation and investigation of copper conductive paths by printing with a different type of functional ink. The solutions based on copper-containing complex compounds were used as inks instead of dispersions of metal nanoparticles. Thermal characteristics of synthesized precursors were studied by thermogravimetry in an argon atmosphere. Based on the comparison of decomposition temperature, the dimethylamine complex of copper formate was found to be more suitable precursor for the formation of copper layers. Structure and performance of this compound was studied in detail by X-ray diffraction, test of wettability, printing on flexible substrate, and electrical measurements.

The development of optoelectronic devices based on flexible organic substrates substantially decreases the possible process temperatures during all stages of device manufacturing. This makes it urgent to search for new transparent conducting oxide (TCO) materials, cheaper than traditional indium-tin oxide (ITO), for the low-temperature deposition of transparent electrodes, a necessary component of most optoelectronic devices. The article presents the results of a vertically integrated study aimed at the low-temperature production of TCO thin films based on a zinc-indium oxide (ZIO) system with acceptable functional characteristics. First, dense and conducting ceramic targets based on the (100-x) mol% (ZnO) + x mol% (In2O3) system (x = 0.5, 1.5, 2.5, 5.0, and 10.0) were synthesized by the spark plasma sintering method. The dependences of the microstructure and phase composition of the ZIO ceramic targets on the In2O3 content have been studied by powder X-ray diffraction, scanning electron microscopy and energy dispersive X-ray spectroscopy methods. Then, a set of ZIO thin films with different Zn/In ratios were obtained on unheated glass substrates by direct current (dc) magnetron sputtering of the sintered targets. Complex studies of microstructure, electrical and optical properties of the deposited films have revealed the presence of an optimal doping level (5 mol% In2O3) of the ZIO target at which the deposited TCO films, in terms of the combination of their electrical and optical properties, become comparable to the widely used expensive ITO.

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