Eco-friendly, low-temperature solution production of oxide thin films for high-performance transistors via infrared irradiation of chloride precursors

Abstract

In this paper, we present the infrared (IR) irradiation of chloride precursors as a promising method for the eco-friendly, low-temperature solution fabrication of oxide film devices, which typically require thermal annealing at temperature over 450 °C. By the IR irradiation of AlCl3 precursor, high-quality Al2O3 dielectric films were prepared at a low temperature of 230 °C. The obtained Al2O3 dielectric layers had high dielectric properties, such as a high capacitance of 158 nF/cm2 and a small leakage current of 5.4 × 10−8 A/cm2. Various structure characterizations confirmed the high quality of Al2O3 films produced by IR irradiation. Moreover, full low-temperature solution-produced thin-film transistors (TFTs) were fabricated through the IR irradiation of chloride precursors. The In2O3 TFTs achieved a high mobility of 33.6 cm2V−1s−1 at a small operation voltage of 4 V. Compared with the common thermal annealing method, IR irradiation results in better precursor conversion, higher oxygen lattice, and fewer oxygen defects. These results suggest that IR irradiation can serve as a new approach for the eco-friendly, low-temperature solution production of various oxide thin films and devices. The method is also very promising for the low-energy production of functional materials and devices.