Anomalous Threshold Voltage Shift and Surface Passivation of Transparent Indium–Zinc–Oxide Electric-Double-Layer TFTs

Author

Sun, Jia ; Jiang, Jie ; Dou, Wei ; Zhou, Bin ; Wan, Qing

Author_Institution

Ningbo Inst. of Mater. Technol. & Eng., Chinese Acad. of Sci., Ningbo, China

Volume

32

Issue

7

fYear

2011

fDate

7/1/2011 12:00:00 AM

Firstpage

910

Lastpage

912

Abstract

Threshold voltage (V_th) instability and surface passivation effect of transparent indium-zinc-oxide electric-double-layer thin-film transistors (TFTs) are investigated. Unpassivated devices show a large negative threshold voltage shift of 0.68 V in the beginning of light-illuminated negative gate bias stress. Under longer time stress, anomalous positive V_th shifts are observed for both unpassivated and passivated TFTs, which is due to the mobile ions drifting in the SiO₂-based solid-electrolyte gate dielectric. After surface passivation, the devices show neglectable negative V_th shifts of less than 0.1 V due to the protection of channel against the photodesorption of adsorbed oxygen ions.

Keywords

indium compounds; passivation; thin film transistors; zinc compounds; InZnO; anomalous threshold voltage shift; light-illuminated negative gate bias stress; solid-electrolyte gate dielectric; surface passivation; thin-film transistors; threshold voltage instability; transparent indium-zinc-oxide electric-double-layer TFT; voltage 0.68 V; Lighting; Logic gates; NIST; Passivation; Stress; Thin film transistors; Electric double layer (EDL); light-illuminated gate bias stress; surface passivation; transparent thin-film transistors (TFTs);

fLanguage

English

Journal_Title

Electron Device Letters, IEEE

Publisher

ieee

ISSN

0741-3106

Type

jour

DOI

10.1109/LED.2011.2146226

Filename

5768065