Operating Temperature Trends in Amorphous In–Ga–Zn–O Thin-Film Transistors

TitleOperating Temperature Trends in Amorphous In–Ga–Zn–O Thin-Film Transistors
Publication TypeJournal Article
Year of Publication2010
AuthorsHoshino, K., and J. F. Wager
JournalIEEE Electron Device Letters
Volume31
Issue8
Pagination818 - 820
Date Published08/2010
ISSN1558-0563
Keywordsgallium compounds, indium compounds, temperature measurement, TFT, thin-film transistors, zinc compounds
Abstract

The electrical performance as a function of operating temperature of amorphous indium gallium zinc oxide (a-IGZO) thin-film transistors (TFTs) is assessed by measuring drain current versus gate voltage [log(ID) - VGS] transfer curves at temperatures from -50°C to +50°C. These bottom-gate staggered a-IGZO TFTs are fabricated using thermal silicon dioxide as the gate insulator. An almost rigid log(ID) - VGS transfer curve shift to lower (more negative) turn-on voltage (VON) with increasing temperature is observed. The extent of the VON operating temperature dependence of a TFT appears to be correlated to its trap density. A lower trap density gives rise to less VON operating temperature dependence. Although log(ID) - VGS transfer curves are observed to shift almost rigidly with temperature, a more detailed temperature-dependence assessment indicates that the shift is not exactly rigid. The mobility is found to increase slightly with increasing operating temperature. This trend is attributed to enhanced detrapping at a higher operating temperature.

DOI10.1109/LED.2010.2049980
Short TitleIEEE Electron Device Lett.