Oxygen-Dependent Instability and Annealing/Passivation Effects in Amorphous In–Ga–Zn–O Thin-Film Transistors

Author

Chen, Wei-Tsung ; Lo, Shih-Yi ; Kao, Shih-Chin ; Zan, Hsiao-Wen ; Tsai, Chuang-Chuang ; Lin, Jian-Hong ; Fang, Chun-Hsiang ; Lee, Chung-Chun

Author_Institution

Dept. of Photonics, Nat. Chiao Tung Univ., Hsinchu, Taiwan

Volume

32

Issue

11

fYear

2011

Firstpage

1552

Lastpage

1554

Abstract

This letter discusses the reason for the instability of amorphous indium-gallium-zinc-oxide (a-IGZO) thin-film transistors (TFTs) under both positive and negative bias stresses. This instability is significantly influenced by the oxygen content in the bulk IGZO and the surrounding environment. The as-fabricated low-temperature devices can only endure a single polarized bias stress. An a-IGZO TFT that is stable toward both positive and negative bias stresses with large relaxation times of 95 × 10⁴ and 371 × 10⁴ s, respectively, is achieved by annealing and passivation.

Keywords

II-VI semiconductors; amorphous semiconductors; annealing; gallium compounds; indium compounds; passivation; stability; thin film transistors; wide band gap semiconductors; zinc compounds; In-Ga-Zn-O; TFT; amorphous thin-film transistors; annealing-passivation effects; low-temperature devices; oxygen content; oxygen-dependent instability; Annealing; Logic gates; Passivation; Stress; Thermal stability; Thin film transistors; Bias stress; IGZO; stability;

fLanguage

English

Journal_Title

Electron Device Letters, IEEE

Publisher

ieee

ISSN

0741-3106

Type

jour

DOI

10.1109/LED.2011.2165694

Filename

6026903