Back to Search Start Over

The Demonstration of Increased Selectivity During Experimental Measurement in Filament-Type Vanadium Oxide-Based Selector.

Authors :
Chen, Chun-Kuei
Lin, Chih-Yang
Chen, Po-Hsun
Chang, Ting-Chang
Shih, Chih-Cheng
Tseng, Yi-Ting
Zheng, Hao-Xuan
Chen, Ying-Chen
Chang, Yao-Feng
Lin, Chun-Chu
Huang, Hui-Chun
Huang, Wei-Chen
Wang, Hao
Sze, Simon M.
Source :
IEEE Transactions on Electron Devices. Oct2018, Vol. 65 Issue 10, p4622-4627. 6p.
Publication Year :
2018

Abstract

In this paper, vanadium oxide (VOx) was chosen for the resistive switching layer in a typical resistive random access memory (RRAM) structure. During negative forming bias, we found an initial selector property. This indicates the presence of metal–insulator-transition characteristics in the VOx layer even without an annealing process. In order to study this phenomenon, material analyses were conducted, with results indicating that there are V-O stretching bonds and an oxide/vanadium ratio of nearly 2.2 (${O}/{V} = {2.2}$). In addition, the experimental results of the dc sweeping test indicated that off-state current gradually decreased after each cycle, meaning that the selectivity characteristics in the VOx selector could be improved. Endurance performance of our experimental devices reached 108, sufficient for integration with RRAM devices in a 1S1R array. To further investigate this special phenomenon, current fitting analysis and simulation analyses were conducted. The results of the fitting analysis indicated that the conduction mechanism for off-state current was Schottky emission and the Schottky distance increased with increasing numbers of cycles. In other words, oxide ions migrate toward the filament at low negative voltage during dc sweeping, causing the formation of VOx. Furthermore, the results of thermal field simulation analysis indicated that there is a thermal concentration effect in and around the filament. Thus, oxide ions more easily migrate toward the vanadium filament when a stronger electrical field is present around the filament during dc sweeping cycles. Finally, stable vanadium selector characteristics are obtained and a conduction filament behavior model is proposed. [ABSTRACT FROM AUTHOR]

Details

Language :
English
ISSN :
00189383
Volume :
65
Issue :
10
Database :
Academic Search Index
Journal :
IEEE Transactions on Electron Devices
Publication Type :
Academic Journal
Accession number :
132684529
Full Text :
https://doi.org/10.1109/TED.2018.2862917