HfO2/TiOx bilayer structure memristor with linear conductance tuning for high density memory and neuromorphic computing

Abstract Human brain synaptic memory simulation based on resistive random access memory (RRAM) has an enormous potential to replace traditional Von Neumann digital computer thanks to several advantages, including its simple structure, high-density integration, and the capability to information storage and neuromorphic computing. Herein, the reliable resistive switching (RS) behaviors of RRAM are demonstrated by engineering AlOx/HfOx bilayer structure. This allows for uniform multibit information storage. Further, the analog switching behaviors are capable of imitate several synaptic learning functions, including learning experience behaviors, short-term plasticity-long-term plasticity transition, and spike-timing-dependent-plasticity (STDP). In addition, the memristor based on STDP learning rules are implemented in image pattern recognition. These results may offer a promising potential of HfOx-based memristors for future information storage and neuromorphic computing applications.

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Discoidal bilayer structure of nascent high density lipoproteins from perfused rat liver.

Journal of Clinical Investigation ◽

10.1172/jci108513 ◽

1976 ◽

Vol 58 (3) ◽

pp. 667-680 ◽

Cited By ~ 428

Author(s):

R L Hamilton ◽

M C Williams ◽

C J Fielding ◽

R J Havel

Keyword(s):

Rat Liver ◽

High Density ◽

High Density Lipoproteins ◽

Bilayer Structure ◽

Perfused Rat Liver

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Versatile Memristor for Memory and Neuromorphic Computing

Nanoscale Horizons ◽

10.1039/d1nh00481f ◽

2022 ◽

Author(s):

Tao Guo ◽

Kangqing Pan ◽

Yixuan Jiao ◽

Bai Sun ◽

Cheng Du ◽

...

Keyword(s):

Retention Time ◽

High Density ◽

Promising Candidate ◽

Neuromorphic Computing

The memristor is a promising candidate to implement high-density memory and neuromorphic computing. Based on the retention time, memristors are classified into volatile and non-volatile types. However, a single memristor...

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2D oriented covalent organic frameworks for alcohol-sensory synapse

Materials Horizons ◽

10.1039/d1mh00315a ◽

2021 ◽

Author(s):

Teng Li ◽

Hongliang Yu ◽

Ziyu Xiong ◽

Zhan Gao ◽

Ye Zhou ◽

...

Keyword(s):

Data Storage ◽

Random Access ◽

High Variability ◽

High Density ◽

Covalent Organic Frameworks ◽

Neuromorphic Computing ◽

Density Data ◽

Potential Applications

Resistive random access memories (RRAMs) based on electrochemical metallization mechanism (ECM) have potential applications in high-density data storage and efficient neuromorphic computing. However, the high variability of ECM device still...

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Post-Moore Memory Technology: Sneak Path Current (SPC) Phenomena on RRAM Crossbar Array and Solutions

Micromachines ◽

10.3390/mi12010050 ◽

2021 ◽

Vol 12 (1) ◽

pp. 50

Author(s):

Ying-Chen Chen ◽

Chao-Cheng Lin ◽

Yao-Feng Chang

Keyword(s):

Random Access ◽

Resistive Random Access Memory ◽

High Density ◽

Bilayer Structure ◽

Crossbar Array ◽

Voltage Stress ◽

Stress Degradation ◽

Intrinsic Nonlinearity ◽

Crossbar Architecture ◽

Read Accuracy

The sneak path current (SPC) is the inevitable issue in crossbar memory array while implementing high-density storage configuration. The crosstalks are attracting much attention, and the read accuracy in the crossbar architecture is deteriorated by the SPC. In this work, the sneak path current problem is observed and investigated by the electrical experimental measurements in the crossbar array structure with the half-read scheme. The read margin of the selected cell is improved by the bilayer stacked structure, and the sneak path current is reduced ~20% in the bilayer structure. The voltage-read stress-induced read margin degradation has also been investigated, and less voltage stress degradation is showed in bilayer structure due to the intrinsic nonlinearity. The oxide-based bilayer stacked resistive random access memory (RRAM) is presented to offer immunity toward sneak path currents in high-density memory integrations when implementing the future high-density storage and in-memory computing applications.

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Bipolar Analog Memristors as Artificial Synapses for Neuromorphic Computing

Materials ◽

10.3390/ma11112102 ◽

2018 ◽

Vol 11 (11) ◽

pp. 2102 ◽

Cited By ~ 17

Author(s):

Rui Wang ◽

Tuo Shi ◽

Xumeng Zhang ◽

Wei Wang ◽

Jinsong Wei ◽

...

Keyword(s):

Complementary Metal Oxide Semiconductor ◽

Building Blocks ◽

Long Term Potentiation ◽

Spike Timing ◽

Oxide Semiconductor ◽

Switching Behavior ◽

Neuromorphic Computing ◽

Training Scheme ◽

Conductance States ◽

Linear Conductance

Synaptic devices with bipolar analog resistive switching behavior are the building blocks for memristor-based neuromorphic computing. In this work, a fully complementary metal-oxide semiconductor (CMOS)-compatible, forming-free, and non-filamentary memristive device (Pd/Al2O3/TaOx/Ta) with bipolar analog switching behavior is reported as an artificial synapse for neuromorphic computing. Synaptic functions, including long-term potentiation/depression, paired-pulse facilitation (PPF), and spike-timing-dependent plasticity (STDP), are implemented based on this device; the switching energy is around 50 pJ per spike. Furthermore, for applications in artificial neural networks (ANN), determined target conductance states with little deviation (<1%) can be obtained with random initial states. However, the device shows non-linear conductance change characteristics, and a nearly linear conductance change behavior is obtained by optimizing the training scheme. Based on these results, the device is a promising emulator for biology synapses, which could be of great benefit to memristor-based neuromorphic computing.

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Ultrafast Switching and Linear Conductance Modulation in Ferroelectric Tunnel Junctions via P(VDF-TrFE) Morphology Control

Nanoscale ◽

10.1039/d1nr01722e ◽

2021 ◽

Author(s):

Sayani Majumdar

Keyword(s):

Energy Range ◽

Tunnel Junctions ◽

Morphology Control ◽

Electronic Components ◽

Neuromorphic Computing ◽

Non Volatile Memory ◽

Ultrafast Switching ◽

Volatile Memory ◽

Conductance Modulation ◽

Linear Conductance

Neuromorphic computing architectures demand development of analog, non-volatile memory components operating at femto-Joule/bit operation energy. Electronic components working at this energy range require devices operating at ultrafast timescales. Among different...

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Planar defects in ordered (Ga,In)P

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100106570 ◽

1988 ◽

Vol 46 ◽

pp. 902-903

Author(s):

S. McKernan ◽

C. B. Carter ◽

D. Bour ◽

J. R. Shealy

Keyword(s):

Electron Diffraction ◽

Vapor Phase ◽

Growth Direction ◽

High Density ◽

Ordered Structure ◽

Planar Defects ◽

Diffraction Patterns ◽

Ternary Semiconductors ◽

Anion Species ◽

Metallic Vapor

The growth of ternary III-V semiconductors by organo-metallic vapor phase epitaxy (OMVPE) is widely practiced. It has been generally assumed that the resulting structure is the same as that of the corresponding binary semiconductors, but with the two different cation or anion species randomly distributed on their appropriate sublattice sites. Recently several different ternary semiconductors including AlxGa1-xAs, Gaxln-1-xAs and Gaxln1-xP1-6 have been observed in ordered states. A common feature of these ordered compounds is that they contain a relatively high density of defects. This is evident in electron diffraction patterns from these materials where streaks, which are typically parallel to the growth direction, are associated with the extra reflections arising from the ordering. However, where the (Ga,ln)P epilayer is reasonably well ordered the streaking is extremely faint, and the intensity of the ordered spot at 1/2(111) is much greater than that at 1/2(111). In these cases it is possible to image relatively clearly many of the defects found in the ordered structure.

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Quantitative defect studies in semiconductor TEM samples prepared by low angle ion milling

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100138932 ◽

1995 ◽

Vol 53 ◽

pp. 512-513

Author(s):

L. Mulestagno ◽

J.C. Holzer ◽

P. Fraundorf

Keyword(s):

Sample Preparation ◽

Milling Time ◽

High Density ◽

Low Density ◽

Ion Milling ◽

High Quality ◽

Variable Angle ◽

Major Disadvantage ◽

Induced Defects

Due to the wealth of information, both analytical and structural that can be obtained from it TEM always has been a favorite tool for the analysis of process-induced defects in semiconductor wafers. The only major disadvantage has always been, that the volume under study in the TEM is relatively small, making it difficult to locate low density defects, and sample preparation is a somewhat lengthy procedure. This problem has been somewhat alleviated by the availability of efficient low angle milling.Using a PIPS® variable angle ion -mill, manufactured by Gatan, we have been consistently obtaining planar specimens with a high quality thin area in excess of 5 × 104 μm2 in about half an hour (milling time), which has made it possible to locate defects at lower densities, or, for defects of relatively high density, obtain information which is statistically more significant (table 1).

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Using the scanning electron microscope for failure analysis of high density magnetic media

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100126755 ◽

1987 ◽

Vol 45 ◽

pp. 392-393

Author(s):

Evelyn R. Ackerman ◽

Gary D. Burnett

Keyword(s):

Electron Microscope ◽

Scanning Electron Microscope ◽

Failure Analysis ◽

High Density ◽

Magnetic Media ◽

Specific Data ◽

Retrieval Systems ◽

Operating Environments ◽

The Media ◽

Scanning Electron

Advancements in state of the art high density Head/Disk retrieval systems has increased the demand for sophisticated failure analysis methods. From 1968 to 1974 the emphasis was on the number of tracks per inch. (TPI) ranging from 100 to 400 as summarized in Table 1. This emphasis shifted with the increase in densities to include the number of bits per inch (BPI). A bit is formed by magnetizing the Fe203 particles of the media in one direction and allowing magnetic heads to recognize specific data patterns. From 1977 to 1986 the tracks per inch increased from 470 to 1400 corresponding to an increase from 6300 to 10,800 bits per inch respectively. Due to the reduction in the bit and track sizes, build and operating environments of systems have become critical factors in media reliability.Using the Ferrofluid pattern developing technique, the scanning electron microscope can be a valuable diagnostic tool in the examination of failure sites on disks.

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