Effect of Extrinsically Introduced Passive Interface Layer on the Performance of Ferroelectric Tunnel Junctions

Rui Guo; Ying Wang; Herng Yau Yoong; Jianwei Chai; Han Wang; Weinan Lin; Shaohai Chen; Xiaobing Yan; Thirumalai Venkatesan; Ariando; Alexei Gruverman; Yihong Wu; Jingsheng Chen

doi:10.1021/acsami.6b15564

Effect of Extrinsically Introduced Passive Interface Layer on the Performance of Ferroelectric Tunnel Junctions

ACS Appl Mater Interfaces. 2017 Feb 15;9(6):5050-5055. doi: 10.1021/acsami.6b15564. Epub 2017 Feb 6.

Authors

Rui Guo^{1

2}, Ying Wang³, Herng Yau Yoong¹, Jianwei Chai⁴, Han Wang¹, Weinan Lin¹, Shaohai Chen¹, Xiaobing Yan¹, Thirumalai Venkatesan^{1

2

3

5

6}, Ariando^{2

5}, Alexei Gruverman⁷, Yihong Wu³, Jingsheng Chen¹

Affiliations

¹ Department of Materials Science and Engineering, National University of Singapore , 117575 Singapore.
² NUSNNI-Nanocore, National University of Singapore , 117411 Singapore.
³ Department of Electrical and Computer Engineering, National University of Singapore , 117583 Singapore.
⁴ Institute of Materials Research and Engineering, Agency for Science, Technology and Research (A*STAR) , 2 Fusionopolis Way #08-01 Innovis, 138634 Singapore.
⁵ Department of Physics, National University of Singapore , 117542 Singapore.
⁶ NUS Graduate School for Integrative Science and Engineering, National University of Singapore , 117576 Singapore.
⁷ Department of Physics and Astronomy and Nebraska Center for Materials and Nanoscience, University of Nebraska , Lincoln, Nebraska 68588-0299, United States.

PMID: 28165212
DOI: 10.1021/acsami.6b15564

Abstract

We report the effect of the top electrode/functional layer interface on the performance of ferroelectric tunnel junctions. Ex situ and in situ fabrication process were used to fabricate the top Pt electrode. With the ex situ fabrication process, one passive layer at the top interface would be induced. Our experimental results show that the passive interface layer of the ex situ devices increases the coercive voltage of the functional BaTiO₃ layer and decreases the tunneling current magnitude. However, the ex situ tunneling devices possess more than 1000 times larger ON/OFF ratios than that of the in situ devices with the same size of top electrode.

Keywords: ON/OFF ratios; ex situ fabrication process; ferroelectric tunnel junctions; in situ fabrication process; passive interface layer.