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http://dx.doi.org/10.4313/JKEM.2009.22.10.821

Fabrication and Characteristics of ZnO TFTs for Flexible Display using Low Temp Process  

Kim, Young-Su (충남대학교 전자공학과)
Kang, Min-Ho (충남대학교 전자공학과)
Nam, Dong-Ho (충남대학교 전자공학과)
Choi, Kang-Il (충남대학교 전자공학과)
Lee, Hi-Deok (충남대학교 전자공학과)
Lee, Ga-Won (충남대학교 전자공학과)
Publication Information
Journal of the Korean Institute of Electrical and Electronic Material Engineers / v.22, no.10, 2009 , pp. 821-825 More about this Journal
Abstract
Recently, transparent ZnO-based TFTs have attracted much attention for flexible displays because they can be fabricated on plastic substrates at low temperature. We report the fabrication and characteristics of ZnO TFTs having different channel thicknesses deposited at low temperature. The ZnO films were deposited as active channel layer on $Si_3N_4/Ti/SiO_2/p-Si$ substrates by RF magnetron sputtering at $100^{\circ}C$ without additional annealing. Also, the ZnO thin films deposited at oxygen partial pressures of 40%. ZnO TFTs using a bottom-gate configuration were investigated. The $Si_3N_4$ film was deposited as gate insulator by PE-CVD at $150^{\circ}C$. All Processes were processed below $150^{\circ}C$ which is optimal temperature for flexible display and were used dry etching method. The fabricated devices have different threshold slop, field effect mobility and subthreshold slop according to channel thickness. This characteristics are related with ZnO crystal properties analyzed with XRD and SPM. Electrical characteristics of 60 nm ZnO TFT (W/L = $20\;{\mu}m/20\;{\mu}m$) exhibited a field-effect mobility of $0.26\;cm^2/Vs$, a threshold voltage of 8.3 V, a subthreshold slop of 2.2 V/decade, and a $I_{ON/OFF}$ ratio of $7.5\times10^2$.
Keywords
ZnO; TFT; Flexible; Low temp process;
Citations & Related Records
Times Cited By KSCI : 3  (Citation Analysis)
연도 인용수 순위
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