Self-Aligned Coplanar a-IGZO TFTs and Application to High-Speed Circuits

Author

Dong Han Kang ; In Kang ; Sang Hyun Ryu ; Jin Jang

Author_Institution

Dept. of Inf. Display, Kyung Hee Univ., Seoul, South Korea

Volume

32

Issue

10

fYear

2011

Firstpage

1385

Lastpage

1387

Abstract

We report a self-aligned coplanar amorphous indium-gallium-zinc-oxide (a-IGZO) thin-film transistor (TFT) using an a-IGZO/SiO₂ stack layer. From the channel-length dependence of the total resistance for the TFTs, the channel and parasitic resistances were found to be 8.4 kΩ/μm and 9.7 kΩ/sq, respectively. The fabricated a-IGZO TFT exhibits field-effect mobility of 23.3 cm²/V ·s, threshold voltage of 3.6 V, and gate voltage swing of 203 mV/dec. A 23-stage ring oscillator made of the self-aligned TFTs exhibits a propagation delay time of 17 ns/stage at a supply voltage of 22 V.

Keywords

gallium compounds; high-speed integrated circuits; indium compounds; oscillators; semiconductor device manufacture; thin film transistors; zinc compounds; high-speed circuits; ring oscillator; self-aligned coplanar TFT; thin-film transistor; voltage 22 V; voltage 3.6 V; Logic gates; Resistance; Solids; Thin film transistors; Threshold voltage; Amorphous indium–gallium–zinc–oxide (a-IGZO); coplanar; ring oscillator (RO); self-aligned process; thin-film transistor (TFT);

fLanguage

English

Journal_Title

Electron Device Letters, IEEE

Publisher

ieee

ISSN

0741-3106

Type

jour

DOI

10.1109/LED.2011.2161568

Filename

5967886