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Abstract: Although significant progress has been made towards using ZnO nanofibers (NFs) in future high‐performance and low‐cost electronics, they still suffer from insufficient device performance caused by substantial surface roughness (i.e., irregularity) and granular structure of the obtained NFs. Here, a simple one‐step electrospinning process (i.e., without hot‐press) is presented to obtain controllable ZnO NF networks to achieve high‐performance, large‐scale, and low‐operating‐power thin‐film transistors. By precisely manipulating annealing temperature during NF fabrication, their crystallinity, grain size distribution, surface morphology, and corresponding device performance can be regulated reliably for enhanced transistor performances. For the optimal annealing temperature of 500 °C, the device exhibits impressive electrical characteristics, including a small positive threshold voltage (Vth) of ≈0.9 V, a low leakage current of ≈10−12 A, and a superior on/off current ratio of ≈106, corresponding to one of the best‐performed ZnO NF devices reported to date. When high‐κ AlOx thin films are employed as gate dielectrics, the source/drain voltage (VDS) can be substantially reduced by 10× to a range of only 0–3 V, along with a 10× improvement in mobility to a respectable value of 0.2 cm2 V−1 s−1. These results indicate the potential of these nanofibers for use in next‐generation low‐power devices. [ABSTRACT FROM AUTHOR]

Although In2O3 nanofibers (NFs) are considered as one of the fundamental building blocks for future electronics, the further development of these NFs devices is still seriously hindered by the large leakage current, low on/off current ratio (Ion/Ioff), and large negative threshold voltage (VTH) due to the excess carriers existed in the NFs. A simple one‐step electrospinning process is employed here to effectively control the carrier concentration of In2O3 NFs by selectively doping strontium (Sr) element to improve their electrical device performance. The optimal devices (3.6 mol% Sr doping concentration) can yield the high field‐effect mobility (μfe ≈ 3.67 cm2 V−1 s−1), superior Ion/Ioff ratio (≈108), and operation in the energy‐efficient enhancement‐mode. High‐κ Al2O3 thin films can also be employed as the gate dielectric to give the gate voltage greatly reduced by 10× (from 40 to 4 V) and the μfe substantially increased by 4.8× (to 17.2 cm2 V−1 s−1). The electrospun E‐mode Sr‐In2O3 NF field‐effect transistors (NFFETs) can as well be integrated into full swing of inverters with excellent performances, further elucidating the significant advance of this electrospinning technique toward practical applications for future low‐cost, energy‐efficient, large‐scale, and high‐performance electronics. High‐performance, low‐power, and enhancement‐mode Sr‐doped In2O2 nanofiber (NFs) transistors are demonstrated with impressive electrical characteristics, including a high mobility (3.67 cm2 V−1 s−1) and an impressive Ion/Ioff ratio (≈108). The device operation voltage can be decreased from 40 to 4 V by further employing high‐κ Al2O3 thin films as gate dielectrics, indicating the potency of these NFs for next‐generation electronics. [ABSTRACT FROM AUTHOR]