Park, S.Y.; Choi, Y.; Seo, Y.H.; Kim, H.; Lee, D.H.; Truong, P.L.; Jeon, Y.; Yoo, H.; Kwon, S.J.; Lee, D.; Cho, E.-S. 355 nm Nanosecond Ultraviolet Pulsed Laser Annealing Effects on Amorphous In-Ga-ZnO Thin Film Transistors. Micromachines2024, 15, 103.
Park, S.Y.; Choi, Y.; Seo, Y.H.; Kim, H.; Lee, D.H.; Truong, P.L.; Jeon, Y.; Yoo, H.; Kwon, S.J.; Lee, D.; Cho, E.-S. 355 nm Nanosecond Ultraviolet Pulsed Laser Annealing Effects on Amorphous In-Ga-ZnO Thin Film Transistors. Micromachines 2024, 15, 103.
Park, S.Y.; Choi, Y.; Seo, Y.H.; Kim, H.; Lee, D.H.; Truong, P.L.; Jeon, Y.; Yoo, H.; Kwon, S.J.; Lee, D.; Cho, E.-S. 355 nm Nanosecond Ultraviolet Pulsed Laser Annealing Effects on Amorphous In-Ga-ZnO Thin Film Transistors. Micromachines2024, 15, 103.
Park, S.Y.; Choi, Y.; Seo, Y.H.; Kim, H.; Lee, D.H.; Truong, P.L.; Jeon, Y.; Yoo, H.; Kwon, S.J.; Lee, D.; Cho, E.-S. 355 nm Nanosecond Ultraviolet Pulsed Laser Annealing Effects on Amorphous In-Ga-ZnO Thin Film Transistors. Micromachines 2024, 15, 103.
Abstract
An ultraviolet (UV) nanosecond pulsed laser with a wavelength of 355 nm was applied to anneal amorphous indium-gallium-zinc oxide (a-IGZO) thin-film transistors (TFT) at various laser beam powers ranging from 0 to 280 mW. Laser irradiation was selectively carried out on the a-IGZO channel area using the beam scanning method after the a-IGZO TFT was formed through indium-tin oxide (ITO) electrode patterning and a subsequent lift-off process. After laser annealing, negative shifts in the threshold voltages and enhanced on-currents were observed at laser-beam powers ranging from 54 to 120 mW. No meaningful parameters were investigated for laser beams higher than 200 mW. By extracting the energy band gap and work function of a-IGZO from the transmittance and ultraviolet photoelectron spectroscopy (UPS) results, the ITO electrode/a-IGZO channel energy band structures were established under different laser annealing conditions, and the electron injection mechanism from the ITO to the a-IGZO channel was analyzed and optimized at a laser beam power of 120 mW. The results show that the electrical characteristics of the a-IGZO TFTs can be improved without any heat damage to the substrate because of the selective annealing process.
Keywords
UV pulsed laser annealing; a-IGZO TFT; ITO/IGZO energy band structure; selective annealing
Subject
Engineering, Electrical and Electronic Engineering
Copyright:
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