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Electrospinning one-dimensional (1-D) semiconductor nanofibers have been regarded as one of the most promising building blocks for future nanoelectronics with high performance because they can exhibit a broad range of device functions. However, electronic devices based on electrospinning-driven nanofibers often suffer from poor performance and inferior quality. In current works, continuous and uniform high-quality indium oxide (In2O3) nanofibers were obtained by electrospinning. The surface morphology, crystallinity, optical, and electrical properties of the In2O3 nanofibers were investigated by X-ray diffraction, scanning electron microscopy, optical spectroscopy, and electrical measurements. It has been detected that the field-effect transistors (FETs) with optimized electrospinning time of 30 s demonstrated superior electrical performance, including a high field-effect mobility (μFE) of 9.1 cm2 ⋅ V−1 ⋅ s−1 and a large ION/IOFF of 107. The high- k Al2O3 dielectric layer has also been used to greatly reduce the operating voltage (from 30 to 3 V), significantly improve μFE (to 27.7 cm2 ⋅ V−1 ⋅ s−1), and strengthen stability over cycling. To prove the device’s potential in more complex logic circuit applications, a resistor-loaded inverter was further integrated, and the maximum voltage gain of 9.8 was demonstrated at an ultralow operating voltage of 3 V. The present findings have demonstrated that electrospinning can potentially be used as a straightforward and cost-effective means for the assembly of 1-D nanostructures for use in next-generation low-power devices. [ABSTRACT FROM AUTHOR]

In current work, InCaOx thin films with different Ca-doping concentrations were prepared via solution-processed method. A systematic investigation was conducted to reveal the variation in the physical properties of InCaOx thin films as a function of Ca-doping concentration by using various characteristic measurements. Results not only demonstrate that Ca-doping can change the optical properties, microstructure, and surface roughness of In2O3 thin films but also indicate that Ca-doping can effectively decrease oxygen vacancies in In2O3 thin films. By measuring the electrical properties of InCaOx/HfGdOx thin-film transistors (TFTs) at a low operating voltage of 5 V, it is noteworthy that Ca-doping can improve the deteriorated performance of In2O3/HfGdOx TFT caused by excessive oxygen vacancies. As Ca-doping concentration reaches 0.5%, InCaOx/HfGdOx TFT manifests superior performances, including a larger μFE of 15.1 cm2V−1s−1 and a higher ION/IOFF of 2.3 × 1/2 107. Furthermore, the stability of In2O3/HfGdOx TFTs under positive bias stress is improved after Ca-doping. Finally, an inverter with a high gain of 6.0 is assembled on the basis of InCaOx/HfGdOx TFT. More importantly, these excellent performances of InCaOx/HfGdOx TFTs are achieved at a low operating voltage, which marks a giant step toward the achievement of low cost and low power consumption electrical devices. [ABSTRACT FROM AUTHOR]

In this work, HfGdOx gate dielectric thin films have been prepared via a nontoxic and environmental-friendly fully water-driven (WD) method. An in-depth investigation has been conducted to reveal the evolution of physical properties in the as-prepared HfGdOx thin films as a function of annealing temperature. Based on the measurements of electrical parameters of the HfGdOx thin films, it is observed that the 500 °C-annealed HfGdOx thin films have shown optimized properties, including a smooth surface, lower leakage current density, and a larger areal capacitance. To validate the feasibility of the HfGdOx gate dielectrics in thin-film transistors (TFTs), In2O3/HfGdOx TFTs have been constructed. The optimized In2O3/HfGdOx TFT exhibited excellent electrical performances, including high field-effect mobility of 11.2 cm2 V−1 s−1, a high ON-/OFF-state current ratio of 4.1 × 106, a small sub-threshold swing of 105.2 mV/decade, and a threshold voltage shift of 0.58 V after 7200-s bias stress, respectively. Finally, based on the In2O3/HfGdOx TFT, an inverter is assembled by connecting an external 3-MΩ resistor. High gain of 8.73 and excellent swing characteristics have been obtained. As a result, it can be inferred that fully WD In2O3/HfGdOx TFTs with high performance will pave the way for achieving low-power-consumption, low-cost, and large-area electronics. [ABSTRACT FROM AUTHOR]

In this article, novel ZrAlOx gate dielectric films were fabricated by a simple, low-cost, and environmentally, eco-friendly, fully water-induced (WI) method for the first time. The microstructure, optical transmittance, surface topography, chemical compositions, and electrical properties of WI ZrAlOx films annealed at 300 °C–600 °C were characterized. Experimental results demonstrated that the 500 °C-annealed WI ZrAlOx film has a good amorphous state, high transmittance, very smooth surface morphology, large area capacitance, and low leakage current density. In order to verify the feasibility of the 500 °C-annealed ZrAlOx film as a dielectric in thin-film transistor (TFT) devices, In2O3/ZrAlOx TFTs were successfully fabricated. The optimized 270 °C-annealed TFT devices have shown excellent electrical characteristics at an extremely low operating voltage of 3 V, including a high $\mu _{{\text {FE}}}$ of 10.14 cm2V−1S−1, a high ${I}_{{\text {on}}}/{I}_{{\text {off}}}$ of ~ 106, a small subthreshold slope (SS) (100 mV dec−1), a low ${V}_{{\text {TH}}}$ (0.36 V), and a small ${N}_{S}^{{\text {max}}}$ ($2.15\times {10}^{{12}}$ cm−2), respectively. To further explore the potential application of In2O3/ZrAlOx TFTs in digital circuits, a resistor-loaded inverter has been constructed and presented good voltage transfer characteristics and high voltage gain. In addition, the dynamic behavior with full swing characteristics has been obtained at a low ${V}_{{\text {DD}}}$ of 2 V. These excellent parameters show their great potential for application in low cost, highly transparent, portable, and low-power consumption electronics. [ABSTRACT FROM AUTHOR]

In this paper, a nontoxic and environmentally friendly water-driven (WD) route to prepare InZnO thin films with various molar ratio of In and Zn has been reported. The formation mechanisms and physical properties of InZnO thin films as a function of element molar ratio are investigated by various characterization techniques. By comparing the performance of InZnO/SiO2 thin-film transistors (TFTs) at different element molar ratio, the results indicate that the molar ratio of 2:1 (In:Zn) is the optimal choice. Based on the optimal molar ratio, fully WD InZnO/HfOx TFT is fabricated and the excellent electrical properties are obtained at a low operating voltage of 5 V, including a higher field-effect mobility of 9.1 cm $^{{2}}\text{V}^{-{1}}\text{s}^{-{1}}$ , a larger ON-/OFF-state current ratio of ${1.5} \times {10}^{{7}}$ , a smaller subthreshold swing of 0.09 V/dec, and a smaller threshold voltage shift of 0.44 V after 5400-s bias stressing, separately. Finally, to further validate the feasibility of InZnO TFTs in complex logic circuits, an inverter is assembled based on the InZnO/HfOx TFT, exhibiting a high gain of 8.8. More importantly, the excellent properties of InZnO/HfOx TFT are achieved at a low-voltage stage, which stands for the great application prospects of WD TFTs in low-cost and excellent performance electronic devices. [ABSTRACT FROM AUTHOR]