Back to Search Start Over

Nanoscale-doped dual-channel for improved performance and reliability of Hf: IGTO / a-IGTO thin film transistor.

Authors :
Kim, Seungjin
Hong, Jin-Hwan
Kim, Dongbhin
Choi, Byoungdeog
Source :
Materials Science in Semiconductor Processing. Jun2024, Vol. 176, pN.PAG-N.PAG. 1p.
Publication Year :
2024

Abstract

Amorphous oxide semiconductors are widely used in the backplane thin film transistors (TFTs) of displays and are extensively researched as materials for next-generation memory devices. However, they face reliability degradation due to stress factors such as thermal, bias, and light exposure. To mitigate these issues, extensive research is focused on improvements, including doping, enhancing crystallinity, and applying pre-and post-treatments. This study investigates the significantly improved reliability and electrical properties of amorphous indium gallium tin oxide (a-IGTO) TFTs by adopting a dual-channel configuration through simultaneous co-sputtering of HfO 2 and IGTO targets. The device fabrication involved co-sputtering HfO 2 and IGTO at the gate oxide interface, followed by depositing an IGTO-only layer, rather than doping the entire channel material. The effect of varying Hf concentration was evaluated by applying different HfO 2 sputtering powers. Optimal hafnium doping reduced the threshold voltage of the a-IGTO TFT from −0.85 V to 0.15 V compared to the pristine a-IGTO TFT, while enhancing the field-effect mobility (μ F E). Furthermore, the Hf-doped device exhibited improved stability, with a reduced threshold voltage shift (Δ V t h ) under positive (+15 V) and negative(-15 V) bias stress at 3000s, decreasing from 11.5 V to 4.8 V , and 4.7 V –1.1 V , respectively. This study proposes a novel device fabrication method to enhance the reliability of amorphous oxide semiconductor, addressing their inherent stress-related issues. [ABSTRACT FROM AUTHOR]

Details

Language :
English
ISSN :
13698001
Volume :
176
Database :
Academic Search Index
Journal :
Materials Science in Semiconductor Processing
Publication Type :
Academic Journal
Accession number :
176390018
Full Text :
https://doi.org/10.1016/j.mssp.2024.108325