Mohamed G. Ahmed, Kyoungrok Cho, and Tae-Won Cho

College of Electrical and Computer Engineering

Chungbuk National University, Republic of Korea

Memristance and Memcapacitance Modeling of Thin Film Devices Showing Memristive Behavior

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Outline

Introduction Periodic Table of Circuit Elements Circuit Elements with memory

Overview of different fabricated memristors Different behavior characteristics Memristor Modeling History Proposed Memristance Model Capacitance of different junctions Proposed behavioral memcapacitance model Conclusions

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Oxygen deficien-cies

Introduction

v q

i Ф

Resistordv=R di

Capacitordq=C dv

InductordФ=L di

MemristordФ=M dq

D. B. Strukov, G. S. Snider, D. R. Stewart, and R. S. Williams, "The missing memristor found," Nature, vol. 453, pp. 80-83, 2008

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Periodic Table of Circuit El-ements

Leon Chua, Nonlinear Circuit Foundations for Nanodevices, Part I The Four-Element Torus, Proceedings of IEEE, vol. 91, 11, Nov. 2003

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Circuit Elements with mem-ory

Massimiliano Di Ventra et al., Circuit Elements With Memory: Memristors, Memcapacitors, and Meminductors, Proceedings of IEEE, vol. 97, 10, 2009

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Overview of different fabricated memris-tors

Material Top Metal

Bottom Metal Ron Roff Year

AlN(Aluminum

nitride)

Cu(Copper)

Pt(Plat-inum)

~103 ~106 2010

AlO(Aluminum

Oxide)

Ti(Tita-nium)

Pt(Plat-inum)

~103 ~5x105 2011

BiFeO3 Ag Pt 102 103~107 2010

ZrO2 Cu Pt 102 108 2008

Cu:SiO2 W Cu 4*104 6x107 2007

Al2O3:RuNCs

TaN Pt 200 5x106 2011

Yb2O3 Ni TaN 102 108 2011

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Memristive Behavior of different fabri-cated memristors

Leon Chua, Resistance switching memories are memristors, Applied Physics A, 102, 2011

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Variations in Memristor Behavior

BehaviorVariations

StructureSpacing

Materials

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Memristor Modeling History

D. B. Strukov, G. S. Snider, D. R. Stewart, and R. S. Williams, "The missing memristor found," Nature, vol. 453, pp. 80-83, 2008D. B. Strukov and R. S. Williams, "Exponential ionic drift: fast switching and low volatility of thin-film memristors," Applied Physics A, vol. 94, pp. 515-519, 2009

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Memristor Modeling History (Cont.)

Kamran Eshraghian et al., Memristive Device Fundamentals and Modeling: Applications to Circuits and Systems Simulation, Proceedings of the IEEE, 2012

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Logarithmic Behavior of memristance modeling

Paper Logarithmic behavior

Strukov et al., Applied Physics A, 94, 2009

Drift velocity – applied volt-age

Hasegawa et al., Advanced Ma-terials, 4, 2012

Channel length – junction current

Hino et al., Sci. Technol. Adv. Mater., 12, 2011

Channel length – junction currentSwitching time – applied voltage

Pickett et al., Journal of applied physics, 106, 2009

Channel length – junction current

Yang et al., Nature Nanotechnol-ogy, 3, 2008

Junction current – applied voltageChannel length – applied voltage

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Memristance Model

[8] Feng Miao et al., Force modulation of tunnel gaps in metal oxide memristive nanoswitches, APPLIED PHYSICS LETTERS 95, 113503, 2009[16] Kamran Eshraghian et al., Memristive Device Fundamentals and Modeling: Applications to Circuits and Systems Simulation, Proceedings of the IEEE, 2012

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Proof of memcapacitance in memristors

Xianwen Sun, Guoqiang Li, Li Chen, Zihong Shi and Weifeng Zhang, Bipolar resistance switching characteristics with opposite polarity of Au/SrTiO3/Ti memory cells, Nanoscale Research Letters 2011, 6:599

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Proof of memcapacitance in memristors

Jie Sun, Erik Lind, Ivan Maximov, and H. Q. Xu, Memristive and Memcapacitive Characteristicsof a Au/Ti–HfO2-InP/InGaAs Diode, IEEE ELECTRON DEVICE LETTERS, VOL. 32, NO. 2, FEBRUARY 2011

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Proof of memcapacitance in memristors

Jie Sun, Erik Lind, Ivan Maximov, and H. Q. Xu, Memristive and Memcapacitive Characteristicsof a Au/Ti–HfO2-InP/InGaAs Diode, IEEE ELECTRON DEVICE LETTERS, VOL. 32, NO. 2, FEBRUARY 2011

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Behavioral Model of Memcapacitance

ε permittivity of the sandwiched materialA device cross section areaAf the effective area of the filamentsdmax the gap length without filamentsdf the gap thickness between filaments and the next electrode

X(t)

Xmax

Xmin

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Proposed memristor model

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Conclusions

Developing new memristance model is not only simple as behavior models, but it also considered to be physical model using some fitting parameters.

Forcing memristance model to work within boundary conditions by choosing new window function which also satisfies logarithmic fashion of drift velocity with junction current.

Including behavioral modeling of junction memcapacitance to model real memris-tor device.

Thank you