Multi-Nonvolatile State Resistive Switching Arising from Ferroelectricity and Oxygen Vacancy Migration

Weiming Lü; Changjian Li; Limei Zheng; Juanxiu Xiao; Weinan Lin; Qiang Li; Xiao Renshaw Wang; Zhen Huang; Shengwei Zeng; Kun Han; Wenxiong Zhou; Kaiyang Zeng; Jingsheng Chen; Ariando; Wenwu Cao; Thirumalai Venkatesan

doi:10.1002/adma.201606165

Multi-Nonvolatile State Resistive Switching Arising from Ferroelectricity and Oxygen Vacancy Migration

Adv Mater. 2017 Jun;29(24). doi: 10.1002/adma.201606165. Epub 2017 Apr 25.

Authors

Weiming Lü¹, Changjian Li^{2

3}, Limei Zheng¹, Juanxiu Xiao^{2

4

5}, Weinan Lin², Qiang Li¹, Xiao Renshaw Wang⁶, Zhen Huang³, Shengwei Zeng³, Kun Han^{3

7}, Wenxiong Zhou^{3

7}, Kaiyang Zeng⁵, Jingsheng Chen^{2

8}, Ariando^{3

7

8}, Wenwu Cao¹, Thirumalai Venkatesan^{2

3

7

8

9}

Affiliations

¹ Condensed Matter Science and Technology Institute, Department of Physics, Harbin Institute of Technology, Harbin, 150001, China.
² Department of Material Science & Engineering, National University of Singapore, Singapore, 117575, Singapore.
³ NUSNNI-Nanocore, National University of Singapore, Singapore, 117411, Singapore.
⁴ State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou, 570228, China.
⁵ Department of Mechanical Engineering, National University of Singapore, Singapore, 117575, Singapore.
⁶ School of Physical and Mathematical Sciences & School of Electrical and Electronic Engineering, Nayang Technological University, Singapore, 637371, Singapore.
⁷ Department of Physics, National University of Singapore, Singapore, 117571, Singapore.
⁸ NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore, 117456, Singapore.
⁹ Department of Electrical and Computer Engineering, National University of Singapore, Singapore, 117576, Singapore.

PMID: 28439926
DOI: 10.1002/adma.201606165

Abstract

Resistive switching phenomena form the basis of competing memory technologies. Among them, resistive switching, originating from oxygen vacancy migration (OVM), and ferroelectric switching offer two promising approaches. OVM in oxide films/heterostructures can exhibit high/low resistive state via conducting filament forming/deforming, while the resistive switching of ferroelectric tunnel junctions (FTJs) arises from barrier height or width variation while ferroelectric polarization reverses between asymmetric electrodes. Here the authors demonstrate a coexistence of OVM and ferroelectric induced resistive switching in a BaTiO₃ FTJ by comparing BaTiO₃ with SrTiO₃ based tunnel junctions. This coexistence results in two distinguishable loops with multi-nonvolatile resistive states. The primary loop originates from the ferroelectric switching. The second loop emerges at a voltage close to the SrTiO₃ switching voltage, showing OVM being its origin. BaTiO₃ based devices with controlled oxygen vacancies enable us to combine the benefits of both OVM and ferroelectric tunneling to produce multistate nonvolatile memory devices.

Keywords: ferroelectric tunnel junctions; multi-nonvolatile memories; oxide interfaces; oxygen vacancies; resistive switching.