Improved Electrical and Thermal Stability of Solution-Processed Li-Doped ZnO Thin-Film Transistors

Author

Su, Bo-Yuan ; Chu, Sheng-Yuan ; Juang, Yung-Der

Author_Institution

Dept. of Electr. Eng., Nat. Cheng Kung Univ., Tainan, Taiwan

Volume

59

Issue

3

fYear

2012

fDate

3/1/2012 12:00:00 AM

Firstpage

700

Lastpage

704

Abstract

The effects of lithium (Li) doping on the performance of solution-processed zinc oxide (ZnO) thin-film transistors (TFTs) grown using the sol-gel method are investigated. Li-doped ZnO films as channel layers are chemically prepared by spin coating the gel with an aqueous solution of zinc acetate dihydrate, Li nitrate, and ethanolamine. TFT devices fabricated with 2 at.% Li-doped films show a good field-effect mobility of 3.31 cm²/V·s, a subthreshold slope of 0.82 V/dec, and an on-off current ratio of over 10⁵. These TFT devices also show good thermal and electrical stability, which is mainly attributed to the compact surface morphology of the channel layer, small carrier concentration, and less oxygen deficiency, which reduces the interface electrical trapping at the gate insulator.

Keywords

electron traps; lithium; stability; thin film transistors; zinc compounds; ZnO:Li; electrical stability; gate insulator; interface electrical trapping; sol gel method; solution processed thin film transistors; thermal stability; Doping; Logic gates; Temperature measurement; Thermal stability; Thin film transistors; Zinc oxide; Thermal stability; zinc oxide (ZnO) thin-film transistors (TFTs);

fLanguage

English

Journal_Title

Electron Devices, IEEE Transactions on

Publisher

ieee

ISSN

0018-9383

Type

jour

DOI

10.1109/TED.2011.2179549

Filename

6129494