We thank AFOSR (contract FA9550-06-1-0076), DOE (subcontract with Los Alamos National Laboratory), and NSF (ECS-0601356) for partial support of this work. P. Trottman acknowledges the NSF PREM Program for summer undergraduate research support.
Solution-Deposited Zinc Oxide and Zinc Oxide/Pentacene Bilayer Transistors: High Mobility n-Channel, Ambipolar, and Nonvolatile Devices†
Article first published online: 10 JUN 2008
Copyright © 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Advanced Functional Materials
Volume 18, Issue 12, pages 1832–1839, June 24, 2008
How to Cite
Pal, B. N., Trottman, P., Sun, J. and Katz, H. E. (2008), Solution-Deposited Zinc Oxide and Zinc Oxide/Pentacene Bilayer Transistors: High Mobility n-Channel, Ambipolar, and Nonvolatile Devices. Adv. Funct. Mater., 18: 1832–1839. doi: 10.1002/adfm.200701430
- Issue published online: 18 JUN 2008
- Article first published online: 10 JUN 2008
- Manuscript Revised: 18 FEB 2008
- Manuscript Received: 6 DEC 2007
- high mobility;
A solution processed n-channel zinc oxide (ZnO) field effect transistor (FET) was fabricated by simple dip coating and subsequent heat treatment of a zinc acetate film. The field effect mobility of electrons depends on ZnO grain size, controlled by changing the number of coatings and zinc acetate solution concentration. The highest electron mobility achieved by this method is 7.2 cm2 V−1 s−1 with On/Off ratio of 70. This electron mobility is higher than for the most recently reported solution processed ZnO transistor. We also fabricated bilayer transistors where the first layer is ZnO, and the second layer is pentacene, a p-channel organic which is deposited by thermal evaporation. By changing the ZnO grain size (or thickness) this type of bilayer transistor shows p-channel, ambipolar and n-channel behavior. For the ambipolar transistor, well balanced electron and hole mobilities are 7.6 × 10−3 and 6.3 × 10−3 cm2 V−1 s−1 respectively. When the ZnO layer is very thin, the transistor shows p-channel behavior with very high reversible hysteresis. The nonvolatile tuning function of this transistor was investigated.