TY - JOUR
T1 - BiFe1- xCrxO3Ferroelectric Tunnel Junctions for Neuromorphic Systems
AU - Kolhatkar, Gitanjali
AU - Mittermeier, Bernhard
AU - Gonzalez, Yoandris
AU - Ambriz-Vargas, Fabian
AU - Weismueller, Marco
AU - Sarkissian, Andranik
AU - Gomez-Yanez, Carlos
AU - Thomas, Reji
AU - Schindler, Christina
AU - Ruediger, Andreas
N1 - Publisher Copyright:
Copyright © 2019 American Chemical Society.
PY - 2019/6/25
Y1 - 2019/6/25
N2 - We report on the fabrication of ferroelectric tunnel junctions of BiFe0.45Cr0.55O3 as a tunneling barrier, Nb-doped (111) SrTiO3 as a bottom electrode, and platinum as a top electrode. BiFeO3 is a generic multiferroic material with perspectives for multiferroic tunnel junctions, with chromium being introduced to shift and enhance the magnetic ordering from canted magnetization to ferrimagnetism. We deposit the ferroelectric films by radio frequency magnetron sputtering, an industry-compatible synthesis method. After confirming the BiFe1-xCrxO3 film composition and its partial crystallinity, we found possible indications of ferroelectricity through piezoresponse force microscopy. X-ray photoelectron spectroscopy together with optical band measurements provide the electronic band profile of the Nb:SrTiO3/BiFe1-xCrxO3/Pt structures. Pulsed electrical characterization reveals resistive switching with very high fatigue resistance (>106 cycles) consistent with direct tunneling across a trapezoidal barrier for a surface fraction of the film. These results make BiFe1-xCrxO3 a promising candidate for ferroelectric tunnel junctions in particular, as they are able to operate as artificial synapses for neuromorphic circuit tiles as evidenced by spike-timing-dependent plasticity.
AB - We report on the fabrication of ferroelectric tunnel junctions of BiFe0.45Cr0.55O3 as a tunneling barrier, Nb-doped (111) SrTiO3 as a bottom electrode, and platinum as a top electrode. BiFeO3 is a generic multiferroic material with perspectives for multiferroic tunnel junctions, with chromium being introduced to shift and enhance the magnetic ordering from canted magnetization to ferrimagnetism. We deposit the ferroelectric films by radio frequency magnetron sputtering, an industry-compatible synthesis method. After confirming the BiFe1-xCrxO3 film composition and its partial crystallinity, we found possible indications of ferroelectricity through piezoresponse force microscopy. X-ray photoelectron spectroscopy together with optical band measurements provide the electronic band profile of the Nb:SrTiO3/BiFe1-xCrxO3/Pt structures. Pulsed electrical characterization reveals resistive switching with very high fatigue resistance (>106 cycles) consistent with direct tunneling across a trapezoidal barrier for a surface fraction of the film. These results make BiFe1-xCrxO3 a promising candidate for ferroelectric tunnel junctions in particular, as they are able to operate as artificial synapses for neuromorphic circuit tiles as evidenced by spike-timing-dependent plasticity.
KW - BiFeCrO
KW - electronic band alignment
KW - endurance
KW - ferroelectric tunnel junctions
KW - neuromorphic systems
KW - spike-timing-dependent plasticity
KW - tunneling electroresistance effect
UR - http://www.scopus.com/inward/record.url?scp=85093579520&partnerID=8YFLogxK
U2 - 10.1021/acsaelm.8b00111
DO - 10.1021/acsaelm.8b00111
M3 - Artículo
AN - SCOPUS:85093579520
SN - 2637-6113
VL - 1
SP - 828
EP - 835
JO - ACS Applied Electronic Materials
JF - ACS Applied Electronic Materials
IS - 6
ER -