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The development of large-scale manufacturing and cost-saving artificial synaptic devices is of great significance for the realization of hardware neural networks. In this work, the In2O3 synaptic transistors with boron ion-doped ZrOx as the dielectric layer were fabricated by the solution process. The large counterclockwise hysteresis indicates that the nonvolatile memory capacity of the synaptic transistors was improved by boron ions doping. Typical synaptic functions including excitatory postsynaptic current, paired pulse facilitation, and high-pass filtering properties were simulated by applying gate bias. The multilevel channel conductance can be modulated by successive positive and negative pulses. Additionally, small nonlinearities were shown in the potentiation and depression processes, and high accuracies of 92.0% (small digits) and 93.8% (large digits) were obtained in digital recognition training. This study indicates that oxide-gated synaptic transistors based on the boron ions doping strategy show great potential for neuromorphic applications. [ABSTRACT FROM AUTHOR]

One-dimensional metal-oxide nanowire networks (NNs) are considered as important elements in electronics due to their unique physical and electrical performances. In this letter, Sn1-x Gax O NNs were fabricated and field-effect transistors (FETs) based on Sn1-x Gax O NNs with different Sn/Ga ratios were constructed. The characteristics of the FETs have been systematically investigated. In order to promote the adhesion and electrical performance of nanowires, Sn1-x Gax O NNs were welded by introducing the polymer mixture containing poly vinyl pyrrolidone and poly methyl methacrylate. Utilizing a welding process, the transport properties of Sn1-x Gax O NNs have been greatly promoted, and the FETs based on Sn0.8 Ga0.2 O NNs exhibit optimum electrical performance. Once integrated with high-k ZrOx dielectric, the FET based on Sn0.8 Ga0.2 O NNs/ZrOx exhibits high stability and high electrical performance, including $\text{a}\mu _{\text{FE}}$ of 5.2 cm2 /V s, an $\text{I}_{\text{on}} /\text{I}_{\text{off}}$ of $1.5\times 10 ^{6}$ , a subthreshold voltage of 170 mV/decade, an on voltage of −0.25 V, and a negligible hysteresis of ~0.12 V. The successful fabrication of the FETs based on Sn0.8 Ga0.2 O NNs lays the foundation for the development of low-consumption, low-cost and high-performance electronic devices. [ABSTRACT FROM AUTHOR]

In this paper, high-k strontium oxide (SrOx) dielectric thin films were fabricated using simple and low-cost solution process. The formation and properties of SrOx thin films annealed at various temperatures (400 °C, 500 °C, 600 °C, and 700 °C) were investigated using numbers of characterization techniques. The electrical analysis indicates that the insulating properties of SrOx thin films were improved with increasing annealing temperature. The post-annealing at temperatures higher than 400 °C enables the SrOx thin film, exhibiting low-leakage current density of ~10−8 A cm−2 at 3 V and the areal capacitance larger than 350 nF cm−2 at 20 Hz. To further explore the possible applications of solution-processed high-k SrOx thin films for thin-film transistors (TFTs), the indium oxide (In2O3) TFTs based on SrOx thin films were integrated for testing. The optimized In2O3/SrOx TFT exhibits high performance with an average field-effect mobility of 5.61 cm2 V−1 s−1, a small subthreshold swing of 110 mV dec−1, and a large on/off current ratio of 107. To demonstrate the potential of In2O3/SrOx TFT toward more complex logic applications, the unipolar inverter was further constructed and exhibited a high gain of 9.7. Importantly, all these device parameters were obtained at an ultralow operating voltage of 3 V, which represents a step toward portable, battery-driven, and low-power consumption electronics and circuits. [ABSTRACT FROM PUBLISHER]

Solution‐processed oxide semiconductor and dielectric thin films have been widely studied for achieving flexible, high‐performance, and low‐power electronics and circuits. In this report, high‐k HfO2 dielectrics and amorphous ZnSnO (ZTO) semiconductors are synthesized via a simple and facile redox reaction by introducing perchloric acid (HClO4, PA) as oxidizer to eliminate the Cl residuals. Thermogravimetric analysis indicates that the thermal decomposition of PA‐involved HfCl4(PA‐HfO2) xerogel is completed at 350 °C, whereas the decomposition temperature of pristine HfCl4 xerogel is higher than 450 °C. The optical, structural, morphological, compositional, and electrical properties of PA‐HfO2 and the pristine HfO2 dielectric films are investigated systematically. Meanwhile, by using chloride elimination reaction, PA‐ZTO semiconducting thin films are fabricated at various temperatures and their applications in thin‐film transistors (TFTs) are examined. Furthermore, the optimized PA‐ZTO channel layer is fabricated on PA‐HfO2 dielectric. The resulting device exhibits high electrical performance and operational stability at a low voltage of 2 V, including high saturation mobility of 13.2 cm2 V−1 s−1, small subthreshold slope of 70 mV dec−1, current ratio of 108, and threshold voltage shift of 0.05 V under positive bias stress for 3000 s. Finally, a low‐voltage resistor‐loaded inverter is built using PA‐ZTO/PA‐HfO2 TFT, exhibiting a linear relationship between supplied voltage and gain voltage and a maximum gain of 11 at 2.5 V. [ABSTRACT FROM AUTHOR]

High‐k alkaline lithium oxide (LiOx) thin films are fabricated by spin‐coating method. The LiOx thin films are annealed at different temperatures and characterized by various techniques. An optimized LiOx dielectric is achieved at an annealing temperature of 300 °C and exhibits wide bandgap of ≈5.5 eV, smooth surface, relatively permittivity of ≈6.7, and low leakage current density. The as‐fabricated LiOx thin films are integrated, as gate dielectrics, in both n‐channel indium oxide (In2O3) and p‐channel cupric oxide (CuO) transistors. The optimized In2O3/LiOx thin‐film transistor (TFT) exhibits high performance and high stability, such as Ion/Ioff of 107, electron mobility of 5.69 cm2 V−1 s−1, subthreshold swing of 70 mV dec−1, negligible hysteresis, and threshold voltage shift of 0.1 V under bias stress for 1.5 h. Meanwhile, the p‐channel CuO TFT based on LiOx dielectric shows high Ion/Ioff of 105 and hole mobility of 1.72 cm2 V−1 s−1. All the electrical performances are achieved at an ultra‐low operating voltage of 2 V. Considering the simple procedure, the moderate annealing temperature, and the low power consumption merits, these outstanding characteristics represent a significant advance toward the development of battery compatible and portable electronics. [ABSTRACT FROM AUTHOR]

Here, a simple, nontoxic, and inexpensive 'water-inducement' technique for the fabrication of oxide thin films at low annealing temperatures is reported. For water-induced (WI) precursor solution, the solvent is composed of water without additional organic additives and catalysts. The thermogravimetric analysis indicates that the annealing temperature can be lowered by prolonging the annealing time. A systematic study is carried out to reveal the annealing condition dependence on the performance of the thin-film transistors (TFTs). The WI indium-zinc oxide (IZO) TFT integrated on SiO2 dielectric, annealed at 300 °C for 2 h, exhibits a saturation mobility of 3.35 cm2 V−1 s−1 and an on-to-off current ratio of ≈108. Interestingly, through prolonging the annealing time to 4 h, the electrical parameters of IZO TFTs annealed at 230 °C are comparable with the TFTs annealed at 300 °C. Finally, fully WI IZO TFT based on YO x dielectric is integrated and investigated. This TFT device can be regarded as 'green electronics' in a true sense, because no organic-related additives are used during the whole device fabrication process. The as-fabricated IZO/YO x TFT exhibits excellent electron transport characteristics with low operating voltage (≈1.5 V), small subthreshold swing voltage of 65 mV dec−1 and the mobility in excess of 25 cm2 V−1 s−1. [ABSTRACT FROM AUTHOR]

Solution-processed AlO x thin films were annealed at different temperatures (250, 350, 450 and 550 °C). The annealing effects on the physical properties of AlO x thin films were studied. It is found that the leakage current density is decreased with increasing annealing temperature. The AlO x thin film annealed at 550 °C exhibits the best insulation performance with a current density of 2.7×10 −9 A/cm 2 at a bias voltage of 3 V. In order to demonstrate the feasibility of application in the thin film transistor (TFT) devices, an indium–titanium–zinc-oxide TFT based on AlO x dielectric was integrated. The TFT can be operated under a low voltage of 5 V, with a high field effect mobility of 23.7 cm 2 /Vs, a threshold voltage of 1.5 V, a subthreshold swing of 0.22 V/decade, and an on/off current ratio of 10 6 . The results demonstrate that AlO x dielectric thin film prepared by solution process is a promising gate dielectric candidate for high-performance oxide devices. The results indicated the potential applications in transparent electronics. [ABSTRACT FROM AUTHOR]