Enhancing Stability of a-IGZO TFTs through Controlled RF Sputtering Power and Hydrogen Quantification
- Author
- Junseo Lee, Jang-Yeon Kwon
- Conference
- ITC 2024
Amorphous Indium Gallium Zinc Oxide (a-IGZO) has emerged as a prominent material in the display industry owing to its exceptional transparency, capacity for low-temperature processing, and cost-effective fabrication facilitated by RF-sputtering techniques. Nevertheless, a-IGZO encounters significant stability challenges, notably when subjected to continuous bias stress, leading to alterations in Thin-Film Transistor (TFT) electrical properties and impeding the stable operation of displays. The stability issues arise from defects associated with hydrogen, which create deep-level states, leading to positive threshold voltage shifts. This study illustrates the quantitative measurement of hydrogen content within a-IGZO thin films, corresponding to different RF sputtering processes, and demonstrates the resulting alterations in device characteristics. We were observed that as power increased, the hydrogen content within the thin film decreased. Consequently, the subthreshold swing (SS) of a-IGZO bottom-gate TFT and the stability of a-IGZO TFT devices exhibited significant improvement.