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With the rapid technological development of thin-film transistors (TFTs), TFTs based on silicon are facing inherent limitations. Finding suitable materials and developing new techniques for fabricating high-performance TFTs is of paramount importance. In this report, a preparation technique for thin films by electrospinning was proposed, in which the thin films were prepared by the melting of nanofibers at low temperature, termed nanofiber-to-films (NTF). The In2O3 and Al2O3 thin films were fabricated by a NTF process and acted as the channel and gate dielectric of TFTs, respectively. High performance TFTs based on In2O3/Al2O3 were demonstrated, including an average field-effect mobility of 13 cm2 V−1 s−1, an on/off current ratio of ∼107, and a subthreshold swing of 0.18 V dec−1. Furthermore, the TFTs based on In2O3/Al2O3 prepared by the NTF process were successfully fabricated on PI substrates. The flexible TFT exhibits an ON voltage of close to 0 V and a subthreshold swing of 0.29 V dec−1. A device array with 4 × 5 units was fabricated and tested, confirming the excellent reproducibility of the flexible TFT. The electrical performance of the flexible TFT after bending cycles was investigated and excellent mechanical stability was demonstrated. The proposed NTF technology provides a promising approach for large-area and low-cost fabrication of flexible oxide electronic devices. [ABSTRACT FROM AUTHOR]

In this study, transparent p-type CuCrxOy semiconductor thin films were fabricated using spin coating and integrated as channel layers in thin-film transistors (TFTs). The structural, morphological components, and optical properties of CuCrxOy thin films, together with device performance, were systematically investigated. The phase conversion from a mixture of CuCr2O4 and CuO to pure CuCrO2 was achieved when the annealing temperature (Ta) was higher than 700 °C. The electrical performance of the CuCrxOy TFTs on SiO2 dielectric is improved with increasing Ta from 500 °C to 800 °C. The optimized CuCrO2 TFT exhibits an on/off current ratio of ∼105 and a hole mobility of 0.59 cm2 V−1 s−1, which is much better than those previous works on solution-processed binary CuxO TFTs. To our best knowledge, this work demonstrates the ternary p-type CuCrO2 TFTs fabricated via a low-cost solution process for the first time, which represents an important advancement towards the development of all-oxide, low-cost p–n junctions and CMOS logic circuits. [ABSTRACT FROM AUTHOR]

Although there are a few research studies on solution-processed p-channel oxide thin-film transistors (TFTs), the strict fabrication conditions and the poor electrical properties have limited their applications in low-power complementary metal oxide semiconductor (CMOS) electronics. Here, the application of the polyol reduction method for processing p-type CuxO and NiOx channel layers and their implementation in TFT devices are reported. The optimized CuxO and NiOx TFTs were achieved at low annealing temperatures (∼300 °C) and exhibited decent electrical properties. Encouraged by the inspiring results obtained on SiO2/Si substrates, the TFT performance was further optimized by device engineering, employing high-k AlOx as the gate dielectric. The fully solution-processed NiOx/AlOx TFT could be operated at a low voltage of 3.5 V and exhibits a high hole mobility of around 25 cm2 V−1 s−1. Our work demonstrates the ability to grow high-quality p-type oxide films and devices via the polyol reduction method over large area substrates while at the same time it provides guidelines for further p-type oxide material and device improvements. [ABSTRACT FROM AUTHOR]