Low-frequency noise and DC I–V characterization of gamma-ray irradiation-induced degradation and trap behaviors in a-IGZO TFTs
Hongseung Lee, Jae‐Hyoung Yoo, Hyeonjun Song, Binhyeong Lee, Soon Joo Yoon, Seongbin Lim, Jo Hak Jeong, Soyeon Kim, Minah Park, S H Park, Sojin Jung, Bhishma Pandit, Taehwan Moon, Jin‐Ha Hwang, Kiyoung Lee, Youn‐Kyoung Lee, Keun Heo, Hagyoul Bae
Abstract
This work reports the impact of gamma-ray (γ-ray) irradiation-induced degradation based on the trap behaviors in amorphous indium-gallium-zinc-oxide (a-IGZO) thin-film transistors. By employing multiple measurement configurations via low-frequency noise and direct current I–V characterization, we quantitatively investigated the energetic distribution of subgap density-of-states in the a-IGZO channel and the spatial distribution of oxide traps (Not) in the gate insulator, respectively. Also, the qualitative analysis was performed to determine the oxygen-related defects after γ-ray irradiation using x-ray photoelectron spectroscopy. Furthermore, the validity of our results was additionally confirmed by measuring the breakdown voltage and applying positive-bias stress to the fabricated devices exposed to radiation for accelerated tests.