Comparative Study of Active-Over-Metal and Metal-Over-Active Amorphous IGZO Thin-Film Transistors With Low-Frequency Noise Measurements

Author

Tsormpatzoglou, Andreas ; Hastas, Nikolaos A. ; Khan, Shahrukh ; Hatalis, Miltiadis ; Dimitriadis, Charalabos A.

Author_Institution

Dept. of Phys., Aristotle Univ. of Thessaloniki, Thessaloniki, Greece

Volume

33

Issue

4

fYear

2012

fDate

4/1/2012 12:00:00 AM

Firstpage

555

Lastpage

557

Abstract

Bottom-gate metal-over-active (MOA) and active-over-metal (AOM) amorphous indium-gallium-zinc-oxide (a-IGZO) thin-film transistors (TFTs), with channel lengths varying from 1 to 16 μm, are investigated with low-frequency noise (LFN) measurements in the linear region of operation. In the low drain-current range, LFN originates from carrier number fluctuations, whereas in the high drain-current range, the noise is affected by the series resistance. The extracted gate-insulator trap densities near the interface lead to the conclusion that the AOM a-IGZO TFTs are superior compared to the MOA devices.

Keywords

II-VI semiconductors; gallium compounds; indium compounds; metallic thin films; noise measurement; thin film transistors; wide band gap semiconductors; zinc compounds; AOM amorphous indium-gallium-zinc-oxide TFT; InGaZnO; LFN measurements; MOA devices; active-over-metal amorphous thin-film transistors; bottom-gate MOA amorphous indium-gallium-zinc-oxide TFT; bottom-gate metal-over-active amorphous thin-film transistors; carrier number fluctuations; extracted gate-insulator trap densities; low-frequency noise measurements; size 1 mum to 16 mum; Logic gates; Low-frequency noise; Resistance; Thin film transistors; Active-over-metal (AOM); indium–gallium–zinc–oxide (IGZO); low-frequency noise (LFN); metal-over-active (MOA); thin-film transistors (TFTs);

fLanguage

English

Journal_Title

Electron Device Letters, IEEE

Publisher

ieee

ISSN

0741-3106

Type

jour

DOI

10.1109/LED.2012.2185677

Filename

6163336