In this work, we demonstrate that back‐channel‐etched a‐ZTO thin‐film transistors (TFTs) are close to realize industrial mass production. The effects of sputtering oxygen partial pressure on the electrical characteristics were mainly explored. Results indicated that both of sub‐threshold swing (SS) and field‐effect mobility (µsat) decreases as oxygen partial pressure increases, while threshold voltage (Vth) increases. The optimal TFTs exhibited the excellent performances: a modest µsat of 7.30 cm2/Vs, a suitable Vth of 5.29V and the SS of 0.41V/decade. Not only the variation of Vth shift (ΔVth) is +1.14 under PBS, but also ΔVth is ‐0.56 under NBS. Compared with IGZO channel layer, the promising ZTO material is abundant and non‐toxic. Therefore relevant TFTs prospectively contribute to reduce industrial production costs and environmental protection.

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The authors investigated optical and electrical properties of MIZO film which was prepared by co‐sputtering for the first time. MgO and IZO (In:Zn=9:1) were used as the two targets to sputter at the same time. By controlling the sputtering power of the two targets, the content of Mg, resistivity and the optical band gap of MIZO can be adjusted, thereby meeting the needs of the applications of UV detector and other purposes. With the increasing of Mg content, the resistivity of MIZO increased from 9.1× 10−4 Ωcm to 6.0 × 108 Ωcm, and the band gap could be broadened to 3.97eV. Except for Mg content, the effect of the ratio of argon to oxygen was also explored, IZO as one of the two targets is very sensitive to the ratio of argon to oxygen, leading to the decrease of the MIZO resistivity of the same magnesium content with the increase of the ratio of argon to oxygen, while the band gap increases first and then decrease.

The deposition of amorphous InGaZnO4 (a-IGZO) semiconductor film, via a sputtering process, has been demonstrated in the literature. In this paper, we present a solution method as an alternative to obtain this semiconducting film. The dispersible IGZO colloids is formed first by co-precipitation of precursors, followed by hydrothermal treatment at 200°C for 1 hour and using CMC as the dispersion agent. The crystalline colloid would become amorphous when it was heated at above 250°C. The TFT structure was made by growing a dielectric silica layer using the CVD method, a metal layer using the sputtering method, and an active IGZO layer using the solution method. This device exhibits low operating voltage, the mobility is about 2cm2V−1s−1 and the Ion/Ioff ratio is 104. Further improvement in processing is needed.

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