Effect of Hydrogen Migration in SiO2/Al2O3 Stacked Gate Insulator of InGaZnO Thin-Film Transistors

Crystals

Sangwook Youn¹  Hyungjin Kim¹  Shinyoung Park²  Jun Tae Jang²  Dae Hwan Kim² 

[1] Department of Electronic Engineering, Inha University, Incheeon 22212, Korea;School of Electrical Engineering, Circadian ICT Research Center, Kookmin University, Seoul 02707, Korea;

关键词: synaptic device;    InGaZnO thin-film transistor;    hydrogen;    low-temperature atomic layer deposition;    XPS;   

DOI  :  10.3390/cryst12050594

来源: DOAJ

【 摘 要 】

In this work, the correlation between SiO₂ deposition thickness and hydrogen content is discussed and the effect of the SiO₂ layer on the properties of synaptic InGaZnO (IGZO) TFTs is analyzed. Three types of IGZO synaptic thin-film transistors (TFTs) were fabricated with different gate insulators, and the effect of SiO₂ as a gate insulator was investigated. XPS analysis confirmed that the hydrogen content in the Al₂O₃ and SiO₂ layers increased during SiO₂ deposition step for all depth regions. Hydrogen injected by the SiO₂ layer deposition step was confirmed to improve the memory window through more threshold voltage shift under positive bias stress (PBS) and negative bias stress (NBS) conditions. In addition, the retention characteristics were improved due to the low hydrogen movement velocity in the SiO₂ layer. These results contribute to the optimization of the amount of hydrogen, and the proposed device has potential as a synaptic device capable of neuromorphic computing.

【 授权许可】

Unknown