Impact of the gate dielectric on contact resistance in high-mobility organic transistors
File(s)
Author(s)
Type
Journal Article
Abstract
The impact of the gate dielectric on contact resistance in organic thin-film transistors (OTFTs) is investigated using electrical characterization, bias-stress stability measurements, and bandgap density of states (DOS) analysis. Two similar dielectric materials, namely Cytop and poly[4,5-difluoro-2,2-bis(trifluoromethyl)-1,3-dioxole-co-tetrafluoroethylene] (Teflon AF2400), are tested in top-gate bottom-contact OTFTs. The contact resistance of Cytop-based OTFTs is found to be greater than that of the AF2400-based devices, even though the metal/OSC interface remains identical in both systems. The Cytop devices are also found to perform worse in bias-stress stability tests which, along with the DOS calculations, suggests that charge trapping at the OSC/dielectric interface is more prevalent with Cytop than AF2400. This increased charge trapping at the Cytop OSC/dielectric interface appears to be associated with the higher contact resistance in Cytop OTFTs. Differences in the molecular structure between Cytop and AF2400 and the large difference in the glass transition temperature of the two polymers may be responsible for the observed difference in the transistor performance. Overall, this study highlights the importance of the gate dielectric material in the quest for better performing OTFTs and integrated circuits.
Date Issued
2019-05-01
Date Acceptance
2019-03-01
Citation
Advanced Electronic Materials, 2019, 5 (5)
ISSN
2199-160X
Publisher
Wiley
Journal / Book Title
Advanced Electronic Materials
Volume
5
Issue
5
Copyright Statement
© 2019 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim. This is the accepted version of the following article: Paterson, A. F., Mottram, A. D., Faber, H., Niazi, M. R., Fei, Z., Heeney, M., Anthopoulos, T. D., Adv. Electron. Mater. 2019, 1800723. which has been published in final form at https://doi.org/10.1002/aelm.201800723
Subjects
Science & Technology
Technology
Physical Sciences
Nanoscience & Nanotechnology
Materials Science, Multidisciplinary
Physics, Applied
Science & Technology - Other Topics
Materials Science
Physics
contact resistance
dielectric
mobility overestimation
organic thin-film transistors
small molecule polymer blends
FIELD-EFFECT TRANSISTORS
THIN-FILM TRANSISTORS
HOLE MOBILITY
PERFORMANCE
PENTACENE
DEPENDENCE
INTERFACES
MORPHOLOGY
STABILITY
TRANSPORT
Publication Status
Published
Article Number
ARTN 1800723
Date Publish Online
2019-03-14