In this study, the effects of femtosecond laser postannealingwere experimentally confirmed by applying it to amorphous indium-gallium-zinc oxide (a-IGZO) thin-film transistor (TFT) with enhanced electrical characteristics. We confirmed that a-IGZO TFTs fabricated by applying femtosecond laser annealing for 50 and 100 s improved more than as-deposited a-IGZO TFTs before annealing. However, a-IGZOTFTs irradiated formore than 150 s degraded in overall performance compared with the as-deposited a-IGZO TFTs. The result of the X-ray photoelectron spectroscopy measurement of the O1s peak on the a-IGZO thin-film indicated that the O ₁ /O _total value dropped to approximately 44.3%, and the O ₃ /O _total value increased to approximately 17.6% when the a-IGZO thin film was irradiated for 150 s. As a result, oxygen vacancies remained without sufficient recovery of the metal-oxygen bond, and as the electron concentration increased, the conductivity increased, and the performance of the TFT decreased due to an increase in leakage current. A resistive load inverter was fabricated by connectinga TFT irradiatedwith the femtosecond laser at the best-performing time of approximately 100 s. The result of measuring the reversal characteristics confirmed a large inversion at the rising and falling edges.

Amorphous indium–gallium–zinc oxide (a-IGZO) is a widely studied semiconductor for cutting-edge electronics applications because of its low absorbance, high charge carrier mobility, and versatility. For the practical application of a-IGZO thin films, postdeposition thermal treatment is typically applied to enhance the device’s performance. Here, we present a study on the effect of oxygen plasma posttreatment of thermally annealed, sputter-deposited a-IGZO thin films to determine the optimal treatment time using a helical plasma source. The performance of devices with a-IGZO active layers exposed to oxygen plasma for different durations is compared, and the stability under constant bias is evaluated. It is found that temporarily exposing the film surface to high-energy oxygen species can improve the charge transport properties, resulting in superior device performance such as more than tenfold increase in the ON–OFF ratio, a nearly doubling of charge carrier mobility and improved bias stress stability. However, under prolonged exposure, the device deteriorates, indicating the importance of properly designing and optimizing the fabrication processes of oxide semiconductor devices. To demonstrate the practical applicability of the transistors with optimized a-IGZO active layers, load-type inverters are prepared, and their performance is evaluated and compared quantitatively to that of a device with a pristine a-IGZO active layer.

The low-temperature annealing process has a critical impact on the electrical performance of thin-film transistors (TFTs). This paper reports significant performance enhancements of TFTs using a femtosecond laser pre-annealing (FLA)-based preparation method. The solution-processed In ₂ O ₃ films were fabricated by FLA at various laser irradiation times and then annealed on a hot-plate at 230 °C. When the FLA time was set to 30 s, the device exhibited high saturation mobility of 10.03 ± 0.64 cm ² /Vs, I _on /I _off of 3.4×10 ⁵ , low V _TH of 0.14 ± 0.64 V, and small SS of 1.44 ± 0.37 V/dec. The FLA process improved the formation of M-O lattices effectively, which led to an improvement in mobility. Furthermore, the gate-bias-stress stability and time-dependent environmental stability were improved considerably by the FLA process. These results show that high-performance In ₂ O ₃ TFTs can be prepared at low temperatures using FLA-centered annealing technology. This work suggests that the FLA preparation method has tremendous potential for the fabrication of low-cost, high performance, and flexible TFT devices.

This paper examined the effects of no treatment versus plasma treatment, and femtosecond laser irradiation as pre-annealing processes on indium zinc oxide (IZO) films and annealing at high temperatures. The plasma pre-annealed multilayer stacked IZO TFTs showed better electrical properties with mobility enhancement from 2.45 to 7.81 cm²/Vs, but exhibited diminished on–off current ratio (I_on/I_off). The IZO thin-film transistor (TFT) prepared with femtosecond laser pre-annealing with low pulse energy generation (power of 3 W at 700 nm wavelength) for 100 s has also exhibited significantly improved electrical performance, the saturation mobility increased to 4.91 cm²/Vs, the I_on/I_off ratio was enhanced from 4.5 × 10⁵ to 2.1 × 10⁶, the threshold voltage improved from − 1.44 to − 0.25 V, and the subthreshold swing was reduced from 1.21 to 0.61 V/dec. In conclusion, IZO TFTs with improved performance can be prepared using a femtosecond laser pre-annealing process, which has great potential for fabricating low-cost, high-performance devices.

In this work, the effect of a UV/ozone source composed of two monochromatic wavelengths of 184 nm and 254 nm irradiated upon the indium oxide film (In ₂ O ₃ ) at the different irradiation times together with annealing at high temperature is explored. The results showed that the developed In ₂ O ₃ thin-film transistors (TFTs) exposed to UV/ozone for the 40 s and annealed at 250 °C for 2 h exhibited a significantly high performance, i.e., saturation mobility of 6.1 ± 0.2 cm $^{2}/$ Vs, $\text{I}_{\mathrm{ on}}/\text{I}_{\mathrm{ off}}$ ratio of $1.4\times10$ ⁷ , low threshold voltage (1.5 ± 0.9 V), and a small subthreshold swing (0.25 V/dec). The in-depth analysis of the developed devices through electrical characteristics, surface morphology, and practical aspect of inverter function confirm that UV/ozone irradiation improves the surface trap density, thereby increasing the mobility, and eventually improves the gate-bias stress stability and time-dependent environmental stability. The current work supports the fact that UV/ozone can improve the electrical properties of In ₂ O ₃ TFTs and can be used for the fabrication of cost-effective, low-temperature, and reliable electronic devices.

Recently, reducing the operating voltage of metal oxide transistors has become a priority because this enables their use in wearable electronics where low power consumption is a requirement. Here, we fabricate transistors that operate under low driving voltage after adding a solution-processed, tungsten-doped indium oxide (IWO) semiconductor deposited on top of a 20 nm aluminum oxide transparent high-k dielectric. To analyze the effect of the tungsten content on the characteristics of IWO thin film transistors (TFTs), devices based on films with 0.11, 0.22, and 0.34 mol% tungsten content were fabricated and compared to pristine indium oxide-based TFTs. Optimized tungsten (W) content at 0.11 mol% achieves a fivefold improvement in the charge carrier mobility, an ON/OFF current ratio two orders of magnitude higher, and the subthreshold swing decreased to less than 0.1 V/dec. The bias stability of the device with optimal W concentration is also significantly better than undoped In $_{\text{2}}$ O $_{\text{3}}$ -based TFTs, probably because doping effectively suppresses the generation of oxygen vacancies in the IWO active channel layer and improves device stability. To test the feasibility of IWO devices in practical applications, a load-type inverter was fabricated using the optimally doped film.