Title: Negative resistance characterisation and defective trap exploration in ZnO nonvolatile memory devices

Authors: Fu-Chien Chiu; Chih-Yao Huang; Wen-Yuan Chang; Tung-Ming Pan

Addresses: Department of Electronic Engineering, Ming Chuan University, 5 De Ming Rd., Gui Shan District, Taoyuan County 333, Taiwan ' Department of Electronics Engineering, Chien Hsin University of Science and Technology, 229 Jianxing Rd., Zhongli city, Taoyuan County 320, Taiwan ' Department of Materials Science and Engineering, National Tsing-Hua University, No. 101, Section 2, Kuang-Fu Road, Hsinchu 30013, Taiwan ' Department of Electronic Engineering, Chang Gung University, 259 Wen-Hwa 1st Road, Kwei-Shan, Taoyuan 333, Taiwan

Abstract: In this work, Pt/ZnO/Pt capacitors were fabricated and investigated for nonvolatile memory applications. The memory devices exhibit bipolar resistance switching characteristics. Using a current-bias method, a negative resistance or snapback characteristic is observed when the memory device switches from a high-resistance state to a low-resistance state owing to the formation of filamentary conducting path. With DC cycling endurance tests, the more set/reset switching cycles are performed, the more times of snapbacks are found. The multiple snapbacks are associated with the additional conducting filaments formed nearby the original filament. By the explorations of temperature-dependent current-voltage characteristics and X-ray photoelectron spectroscopy spectra, the filaments may be related to the defect state of interstitial zinc with the trap spacing of 2 nm and the trap energy level of 0.46 eV in ZnO films.

Keywords: ZnO nonvolatile memory; zinc oxide; bipolar resistance switching; negative resistance; defect state; nanoelectronics; nanotechnology; defective trap exploration.

DOI: 10.1504/IJNT.2014.059818

International Journal of Nanotechnology, 2014 Vol.11 No.1/2/3/4, pp.145 - 155

Published online: 13 Mar 2014 *

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