Ferroelectric tunnel junctions with graphene electrodes

Authors

Haidong Lu, University of Nebraska-LincolnFollow
Alexey Lipatov, University of Nebraska-LincolnFollow
Sangjin Ryu, University of Wisconsin-MadisonFollow
D. J. Kim, University of Nebraska - Lincoln
H. Lee, University of Wisconsin-Madison
M. Ye. Zhuravlev, Kurnakov Institute for General and Inorganic Chemistry, Russian Academy of Sciences, Moscow, RussiaFollow
Chang-Beom Eom, University of Wisconsin-MadisonFollow
Evgeny Y. Tsymbal, University of Nebraska-LincolnFollow
Alexander Sinitskii, University of Nebraska-LincolnFollow
Alexei Gruverman, University of Nebraska-LincolnFollow

Date of this Version

11-24-2014

Citation

NATURE COMMUNICATIONS 5, 5518 (2014). DOI: 10.1038/ncomms6518

Comments

Copyright 2014 NATURE PUBLISHING GROUP. Used by permission.

Abstract

Polarization-driven resistive switching in ferroelectric tunnel junctions (FTJs)—structures composed of two electrodes separated by an ultrathin ferroelectric barrier—offers new physics and materials functionalities, as well as exciting opportunities for the next generation of non-volatile memories and logic devices. Performance of FTJs is highly sensitive to the electrical boundary conditions, which can be controlled by electrode material and/or interface engineering. Here, we demonstrate the use of graphene as electrodes in FTJs that allows control of interface properties for significant enhancement of device performance. Ferroelectric polarization stability and resistive switching are strongly affected by a molecular layer at the graphene/BaTiO₃ interface. For the FTJ with the interfacial ammonia layer we find an enhanced tunnelling electroresistance (TER) effect of 6 x 10⁵%. The obtained results demonstrate a new approach based on using graphene electrodes for interface-facilitated polarization stability and enhancement of the TER effect, which can be exploited in the FTJbased devices.