Investigation of low to high-dose gamma-ray (γ-ray) radiation effects on indium-zinc-oxide (IZO) thin film transistor (TFT)

• Published in: Solid-state electronics 2024-05, Vol.215, p.108884, Article 108884
• Main Authors: Kim, Do-Kywn, Kim, Dong-Seok, Kim, Tae-Eon, Kim, Min-Ju, Shin, Seung Heon
• Format: Article
• Language: English
• ISSN: 0038-1101; 1879-2405
• DOI: 10.1016/j.sse.2024.108884

•The impact of gamma-ray radiation on each IZO TFT is investigated through XPS analysis and the electrical properties.•The Vth, SS, gm,max, and µFE are investigated at doses of 100 krads and 1,000 krads, respectively.•Our findings indicate the IZO TFT shows a significant potential for a radiation-hardness electronic device in harsh environments. This paper investigates the impact of gamma-ray (γ-ray) radiation at doses of 100 krads and 1,000 krads on amorphous indium-zinc-oxide (IZO) thin-film transistors (TFTs). The IZO channel's properties are analyzed using X-ray photoelectron spectroscopy (XPS) before and after radiation. Following 100 krads exposure, the oxygen vacancy (VO) peak in the IZO channel increases from 41.8 % to 59.4 % due to the generation of electron-hole pairs. Additionally, the threshold voltage of the IZO TFT negatively shifts from 10.1 V to 5.5 V due to positive charges in the gate oxide layer. Following exposure to 1,000 krads gamma-ray radiation, the threshold voltage of 8.8 V is similar to that of 9.8 V for the non-irradiated TFT. Remarkably, the subthreshold swing (SS) remains unchanged, while the maximum transconductance (gm,max) is improved by 10.0 % and effective mobility (µFE) by 6.1 %. These enhancements result from the diffusion of indium, zinc, and oxygen into the gate oxide layer thanks to the self-heating effect at a dose of 1,000 krads. Based on the results, our findings indicate the IZO TFT shows a significant potential for a radiation-hardness electronic device in harsh environments.