Low-temperature and rapid photo-annealing process for metal-oxide thin-film transistors using combined excimer deep-ultraviolet and intensely pulsed light irradiation

Abstract

The fabrication of high-performance metal-oxide-based thin-film transistors (TFTs) on flexible and transparent polymer substrates by solution processes has garnered substantial interest, particularly for manufacturing flexible electronics. However, the annealing conditions for metal oxides, which require a high annealing temperature and prolonged annealing time, have been a crucial barrier to fabricate metal-oxide TFTs on polymer substrates. In this study, using a photo-annealing method based on combined excimer deep ultraviolet (EDUV) and intensely pulsed light (IPL) treatments. The EDUV has a peak at 172 nm and irradiates energy with an intensity of 65 mW/cm 2 onto the target material. A Xenon lamp was used for IPL treatment with an irradiation energy fluence of 1.8 J/cm 2 when applied for one pulse duration. The total applied energy was controlled by the number of treatment pulses. The previous results of annealing temperature and annealing time of 140 °C and 15 min were reduced to 130 °C and 10 min, respectively. Moreover, a mobility of 5.35 cm 2 /Vs and on–off ratio of 10 6 were achieved. The optimal processing conditions determined in this study are applicable to polymer substrates and are expected to contribute to the production of transparent electronic devices on high-performance, large-area flexible substrates through continuous roll-to-roll printing. • Excimer deep ultraviolet and intensely pulsed light for annealing thin metal oxides. • Applicable to thin film transistors on transparent polymer substrates. • Experimentally optimized annealing time and temperature for transistor performance. • Physically characterized by X-ray photoelectron-spectra, X-ray diffraction analysis. • Increased feasability of transparent electronic devices on polymer substrates.