Resistive switching: An investigation of the bipolar–unipolar transition in Co-doped ZnO thin films

Journal Article · Mon Jun 15 00:00:00 EDT 2015 · Materials Research Bulletin

DOI:https://doi.org/10.1016/J.MATERRESBULL.2015.02.051· OSTI ID:22475798

Zeng, Hao ^[1]; Macêdo, Marcelo A. ^[2]

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1. Department of Physics, University at Buffalo, The State University of New York, Buffalo, NY 14260 (United States)
2. Department of Physics, Federal University of Sergipe, São Cristóvão 49100-000 (Brazil)

Highlights: • A purely bipolar behavior on a Co-doped ZnO thin film has been demonstrated. • We have shown what can happen if a unipolar test is performed in a purely bipolar device. • An explanation for how a sample can show a purely bipolar switching behavior was suggested. • An important open issue about resistive switching effect was put in debate. - Abstract: In order to investigate the resistive switching effect we built devices in a planar structure in which two Al contacts were deposited on the top of the film and separated by a small gap using a shadow mask. Therefore, two samples of 10% Co-doped ZnO thin films were sputtered on glass substrate. High resolution X-ray diffraction (HRXRD) revealed a highly c-axis oriented crystalline structure, without secondary phase. The high resolution scanning electron microscopy (HRSEM) showed a flat surface with good coverage and thickness about 300 nm. A Keithley 2425 semiconductor characterization system was used to perform the resistive switching tests in the bipolar and unipolar modes. Considering only the effect of compliance current (CC), the devices showed a purely bipolar behavior since an increase in CC did not induce a transition to unipolar behavior.

• OSTI ID: 22475798
• Journal Information: Materials Research Bulletin, Vol. 66; Other Information: Copyright (c) 2015 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0025-5408
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
COBALT ADDITIONS
DOPED MATERIALS
ELECTRICAL PROPERTIES
RESOLUTION
SCANNING ELECTRON MICROSCOPY
SEMICONDUCTOR MATERIALS
SEMICONDUCTOR SWITCHES
SPUTTERING
SUBSTRATES
SURFACES
THIN FILMS
X-RAY DIFFRACTION
ZINC OXIDES