Unraveling the origin of ferroelectric resistance switching through the interfacial engineering of layered ferroelectric-metal junctions

AbstractFerroelectric memristors have found extensive applications as a type of nonvolatile resistance switching memories in information storage, neuromorphic computing, and image recognition. Their resistance switching mechanisms are phenomenally postulated as the modulation of carrier transport by polarization control over Schottky barriers. However, for over a decade, obtaining direct, comprehensive experimental evidence has remained scarce. Here, we report an approach to experimentally demonstrate the origin of ferroelectric resistance switching using planar van der Waals ferroelectric α-In2Se3 memristors. Through rational interfacial engineering, their initial Schottky barrier heights and polarization screening charges at both terminals can be delicately manipulated. This enables us to find that ferroelectric resistance switching is determined by three independent variables: ferroelectric polarization, Schottky barrier variation, and initial barrier height, as opposed to the generally reported explanation. Inspired by these findings, we demonstrate volatile and nonvolatile ferroelectric memristors with large on/off ratios above 104. Our work can be extended to other planar long-channel and vertical ultrashort-channel ferroelectric memristors to reveal their ferroelectric resistance switching regimes and improve their performances.

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Photovoltaic effect and Schottky barriers in the Au–In1−xGaxSb system

Canadian Journal of Physics ◽

10.1139/p80-010 ◽

1980 ◽

Vol 58 (1) ◽

pp. 63-67 ◽

Cited By ~ 7

Author(s):

W. J. Keeler ◽

A. P. Roth ◽

E. Fortin

Keyword(s):

Temperature Dependence ◽

Schottky Barrier ◽

System Analysis ◽

Photovoltaic Effect ◽

Alloy System ◽

Schottky Barriers ◽

Type Region ◽

Barrier Heights ◽

P Type

The temperature dependence of the photovoltaic effect between 6 and 300 K has been measured on the Au–In1−xGaxSb system. Analysis of the data gives the Schottky barrier heights across the alloy system. In the n-type region of the system (InSb rich) the barrier is found to be [Formula: see text] while in the p-type region (GaSb rich) it is [Formula: see text].

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Fermi Level Pinning in Au Schottky Barriers on InGaP and InGaAlP

MRS Proceedings ◽

10.1557/proc-340-265 ◽

1994 ◽

Vol 340 ◽

Author(s):

V.A. Gorbyley ◽

A.A. Chelniy ◽

A.A. Chekalin ◽

A.Y. Polyakov ◽

S.J. Pearon ◽

...

Keyword(s):

Quantum Well ◽

Fermi Level ◽

Plasma Treatment ◽

Schottky Barrier ◽

Hydrogen Plasma ◽

Schottky Diodes ◽

Schottky Barriers ◽

Quantum Well Structures ◽

Fermi Level Pinning ◽

Barrier Heights

ABSTRACTIt is shown that in Au/InGaP and Au/InGaAlP Schottky diodes the Fermi level is pinned by metal-deposition-induced midgap states. Hydrogen plasma treatment of such diodes greatly improves the reverse currents. The measured Schottky barrier heights seem to correlate with the valence band offsets measured by DLTS on quantum well structures.

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Schottky Barrier Heights of PT Silicides on SiGe

MRS Proceedings ◽

10.1557/proc-320-293 ◽

1993 ◽

Vol 320 ◽

Author(s):

J.R. Jimenez ◽

X. Xiao ◽

J.C. Sturm ◽

P.W. Pellegrini ◽

M. Chi

Keyword(s):

Schottky Barrier ◽

Barrier Height ◽

Schottky Diodes ◽

Infrared Detector ◽

Schottky Barriers ◽

Band Offset ◽

Barrier Heights ◽

Semiconductor Interfaces ◽

Metal Thickness ◽

Deposited Metal

ABSTRACTSilicide/SiGe Schottky barriers are of importance for applications in infrared detectors and SiGe contacts, as well as for fundamental studies of metal-semiconductor interfaces. We have fabricated silicide/SiGe Schottky diodes by the reaction of evaporated Pt and Ir films on p-SiGe alloys with a thin Si capping layer. The onset of metal-SiGe reactions was controlled by the deposited metal thickness. The Schottky barrier heights were determined from internal photoemission. Pt-SiGe and Ir-SiGe reacted diodes have barrier heights that are higher than the corresponding silicide/p-Si diodes. PtSi/Si/SiGe diodes, on the other hand, have lower “barrier heights” that decrease with increasing Ge concentration. The smaller barrier heights in such silicide/Si/SiGe diodes are due to tunneling through the unconsumed Si layer. Equations are derived accounting for this tunneling contribution, and lead to an extracted “barrier height” that is the Si barrier height reduced by the Si/SiGe band offset. Highly bias-tunable barrier heights are obtained (e.g. 0.30 eV to 0.12 eV) by allowing the SiGe/Si band offset to extend higher in energy than the Schottky barrier, leading to a cut-off-wavelength-tunable silicide/SiGe/Si Schottky diode infrared detector.

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Schottky Barriers on a-Si:H,F/a-Si,Ge:H,F Superlattices

MRS Proceedings ◽

10.1557/proc-95-375 ◽

1987 ◽

Vol 95 ◽

Author(s):

V. Chu ◽

J. P. Conde ◽

S. Aljishi ◽

D. S. Shen ◽

Z E. Smith ◽

...

Keyword(s):

Schottky Barrier ◽

Carrier Mobility ◽

Schottky Barrier Height ◽

Minority Carrier ◽

Voltage Dependence ◽

Internal Quantum Efficiency ◽

Schottky Barriers ◽

Multilayer Structures ◽

Barrier Heights ◽

Minority Carrier Mobility

AbstractWe report measurements of Schottky barrier heights and minority carrier mobilitylifetime products of multilayer structures composed of a-Si:H,F and a-Si,Ge:H,F. These layers are grown by r.f. glow discharge decompostion of SiF4, GeF4, and H2 in the a-Si,Ge:H,F (well) layer and of SiF4 and H2 in the a-Si:H,F (barrier) layer.Schottky barrier height ΦB of Pt is measured using internal photoemission measurements. The minority carrier mobility-lifetime product (μτ)p is extracted from a fit of the voltage dependence of internal quantum efficiency to the Hecht expression. Both ΦB and (μτ)p are measured as a function of barrier and well thicknesses.

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Thermal Stability of Tasix-Gaas Schottky Barriers

MRS Proceedings ◽

10.1557/proc-92-381 ◽

1987 ◽

Vol 92 ◽

Cited By ~ 2

Author(s):

T. E. Haynes ◽

C. C. Han ◽

S. S. Lau ◽

S. T. Picraux ◽

W. K. Chu

Keyword(s):

Thermal Stability ◽

Schottky Barrier ◽

Thermal Processing ◽

Rapid Thermal Processing ◽

Physical Characteristics ◽

Schottky Barriers ◽

Electrical Characteristics ◽

Furnace Annealing ◽

Barrier Heights ◽

Thermal Stability Of

ABSTRACTSputtered TaSix films on GaAs have been examined as potential refractory Schottky barrier contacts suitable for self-aligned gate fabrication of GaAs MESFETs. The thermal stability of electrical and physical characteristics has been studied following furnace annealing or rapid thermal processing of contacts with compositions near Ta5Si3 (x=06). The electrical characteristics, interface interdiffusion, and evaporation loss of Ga and As through the contact have been examined. The barrier heights of 30-min furnaceannealed contacts were found to increase with temperature over the range 600 to 900°C. The Schottky barrier heights after rapid thermal processing (RTP) of the contacts were fixed at 0.78 eV for temperatures in the range 700 to 900°C. A major finding of this work is that the Schottky barrier contact maintains its integrity even though the equivalent of at least 5 monolayers of Ga and As have decomposed and evaporated through the contact.

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Oxygen stabilization of molecular beam epitaxial Al‐GaAs Schottky barrier heights

Journal of Applied Physics ◽

10.1063/1.331194 ◽

1982 ◽

Vol 53 (6) ◽

pp. 4521-4523 ◽

Cited By ~ 5

Author(s):

K. Okamoto ◽

C. E. C. Wood ◽

L. Rathbun ◽

L. F. Eastman

Keyword(s):

Schottky Barrier ◽

Molecular Beam ◽

Molecular Beam Epitaxial ◽

Barrier Heights

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Tuning of NiSi∕Si Schottky barrier heights by sulfur segregation during Ni silicidation

Applied Physics Letters ◽

10.1063/1.1863442 ◽

2005 ◽

Vol 86 (6) ◽

pp. 062108 ◽

Cited By ~ 121

Author(s):

Q. T. Zhao ◽

U. Breuer ◽

E. Rije ◽

St. Lenk ◽

S. Mantl

Keyword(s):

Schottky Barrier ◽

Sulfur Segregation ◽

Barrier Heights

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Schottky barrier heights of epitaxial Ni–silicides on Si(111)

Journal of Vacuum Science & Technology A Vacuum Surfaces and Films ◽

10.1116/1.573795 ◽

1986 ◽

Vol 4 (3) ◽

pp. 855-859 ◽

Cited By ~ 17

Author(s):

M. Liehr ◽

P. E. Schmid ◽

F. K. LeGoues ◽

P. S. Ho

Keyword(s):

Schottky Barrier ◽

Barrier Heights ◽

Ni Silicides

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Correlation between the Location of the Interface State Minimum at Insulator-Semiconductor Interfaces and Schottky Barrier Heights

Japanese Journal of Applied Physics ◽

10.1143/jjap.25.l353 ◽

1986 ◽

Vol 25 (Part 2, No. 5) ◽

pp. L353-L356 ◽

Cited By ~ 4

Author(s):

Hideo Ohno ◽

Hideki Hasegawa

Keyword(s):

Schottky Barrier ◽

Interface State ◽

Barrier Heights ◽

Semiconductor Interfaces

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Nanoscale Deep Level Defect Correlation with Schottky Barriers in 4H-SiC/Metal Diodes

Materials Science Forum ◽

10.4028/www.scientific.net/msf.527-529.907 ◽

2006 ◽

Vol 527-529 ◽

pp. 907-910

Author(s):

Sergey P. Tumakha ◽

L.M. Porter ◽

D.J. Ewing ◽

Qamar-ul Wahab ◽

X.Y. Ma ◽

...

Keyword(s):

Surface Defect ◽

Deep Level ◽

Polarized Light ◽

Schottky Barriers ◽

Double Barrier ◽

Barrier Heights ◽

Current Voltage ◽

Cathodoluminescence Spectroscopy ◽

Morphological Defects ◽

Additional Defect

We have used depth-resolved cathodoluminescence spectroscopy (DRCLS) to correlate subsurface deep level emissions and double barrier current-voltage (I-V) characteristics across an array of Ni/4H-SiC diodes on the same epitaxial wafer. These results demonstrate not only a correspondence between these optical features and measured barrier heights, but they also suggest that such states may limit the range of SB heights in general. DRCLS of near-ideal diodes show a broad 2.45 eV emission at common to all diode areas and associated with either impurities or inclusions. Strongly non-ideal diodes exhibit additional defect emissions at 2.2 and 2.65 eV. On the other hand, there is no correlation between the appearance of morphological defects observed by polarized light microscopy or X-ray topography and the presence of double barrier characteristics. The DRCLS observations of defect level transitions that correlate with non-ideal Schottky barriers suggest that these sub-surface defect features can be used to predict Schottky barrier behavior.

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