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Current issue   Ukr. J. Phys. 2017, Vol. 62, N 8, p. 699-704
https://doi.org/10.15407/ujpe62.08.0699    Paper

Rasheed H.S.1,2, Ahmed Naser M.1, Matjafri M.Z.1

1 Institute of Nano-Optoelectronics Research and Technology Laboratory (INOR),
Universiti Sains Malaysia, School of Physics
(Penang, Malaysia)
2 Department of Physics, College Of Education, Al-Mustansiriya University
(Baghdad, Iraq)

New ZnO/Au/ZnO Multilayer Field Effect Transistor with Extended Gate as a Sensing Membrane

Section: Solid Matter
Original Author's Text: Ukrainian/English

Abstract: ZnO/Au/ZnO (ZAuZ) multilayer structures with diferent thicknesses are deposited on a glass substrate by using the RF and DC magnetron sputtering methods and then are used as extended
gates in feld efect transistors (FET) for the pH detection. Their structural, optical, and
electrical properties are investigated. The thickness parameter afected the pH sensitivity of the
multilayers, by increasing the sensitivity from 0.25 A1/2/pH to 0.3 A1/2/pH in the saturation
region and from 50 mV/pH to 66.66 mV/pH in the linear region. On the contrary, in the
hysteresis voltage case, it is reduced from 10.11 mV to 9.87 mV, as the thickness of multilayers
increases from (100/50/100) nm to (200/100/200) nm.

Key words: EGFET, ZnO, hysteresis, multilayers, MOSFET.


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