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• InGaSnO thin film transistors (TFTs) with high mobility (>50 cm2/Vs) were prepared. • Gallium doping improves the electrical performance and stability of InGaSnO TFTs. • The thermal budget can be controled below 150 ℃ without other equipment and process. • Oxygen vacancy and interfacial defect density can be reduced by gallium doping. In this work, InGaSnO thin film transistors (TFTs) with high mobility (>50 cm2/Vs) were prepared by a simple co-sputtering process at a low temperature of 150 ℃. In the co-sputtering process of InSnO and Ga 2 O 3 , the composition of InGaSnO can be reasonably controlled by adjusting the sputtering power in the radio frequency plasma, which significantly affects the electrical performance and stability of InGaSnO TFTs. The highly overlapping 5 s electron cloud of In and Sn and the high binding energy of Sn-O lay the foundation for the high mobility of InGaSnO TFTs. The defects related to oxygen in the channel are suppressed by the reasonable control of the composition of Ga in the multicomponent oxides. Meanwhile, the interface defects between the gate dielectric and the active layer are reduced, and a dense metal-oxygen-metal network is formed which is conducive to electron transmission. We have achieved an InGaSnO TFTs with mobility of 58.7 cm2/Vs and threshold voltage of -1.33 V. The stability under positive and negative bias stress is also significantly improved. In general, a simple co-sputtering process is entirely feasible to realize high-mobility oxide TFTs. The control of the process temperature below 150 ℃ also extends its application in flexible electronic devices. [ABSTRACT FROM AUTHOR]

[Display omitted] • The InGaSnO thin film transistors after in-situ Ar plasma treatment enhanced the electrical performance and stability. • In-situ Ar plasma processing is simple, time-saving, and does not depend on other external equipment, reducing the thermal budget. • In-situ Ar plasma treatment reduces oxygen vacancy and interfacial defect density, reduces surface roughness, and improves film quality. High-performance InGaSnO thin film transistors are successfully fabricated with a reduced thermal budget by an in-situ Ar plasma treatment process. This process does not require external equipment for plasma treatment of the deposited film, which ensures the original vacuum environment and uses plasma energy for weak treatment. The atomic force microscope measurement shows that the surface roughness of the InGaSnO thin film decreased from 0.472 nm to 0.266 nm after treatment. The reduction of oxygen vacancy defect states is verified by the O 1s spectrum of X-ray photoelectron spectroscopy, and its interfacial defect density is also significantly reduced. The stabilities of InGaSnO TFTs are also considerably improved, with the threshold voltage shift under the negative bias stress test reduced to 0.39 V, better than annealing at 300 °C. Ar plasma treatment improves film quality and enhances device performance, which exhibits high field-effect mobility (30.8 cm2/Vs), a small sub-threshold swing (0.32 V/decade), and a low threshold voltage (−0.54 V). Overall, in-situ Ar plasma treatment not only reduces the thermal budget but also simplifies the process, enabling the utility of long-term high-temperature annealing, showing its potential in flexible display applications. [ABSTRACT FROM AUTHOR]