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Yadav R, Poudyal S, Rajarapu R, Biswal B, Barman PK, Kasiviswanathan S, Novoselov KS, Misra A. Low Power Volatile and Nonvolatile Memristive Devices from 1D MoO 2-MoS 2 Core-Shell Heterostructures for Future Bio-Inspired Computing. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024; 20:e2309163. [PMID: 38150637 DOI: 10.1002/smll.202309163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 12/05/2023] [Indexed: 12/29/2023]
Abstract
Memristors-based integrated circuits for emerging bio-inspired computing paradigms require an integrated approach utilizing both volatile and nonvolatile memristive devices. Here, an innovative architecture comprising of 1D CVD-grown core-shell heterostructures (CSHSs) of MoO2-MoS2 is employed as memristors manifesting both volatile switching (with high selectivity of 107 and steep slope of 0.6 mV decade-1) and nonvolatile switching phenomena (with Ion/Ioff ≈103 and switching speed of 60 ns). In these CSHSs, the metallic core MoO2 with high current carrying capacity provides a conformal and immaculate interface with semiconducting MoS2 shells and therefore it acts as a bottom electrode for the memristors. The power consumption in volatile devices is as low as 50 pW per set transition and 0.1 fW in standby mode. Voltage-driven current spikes are observed for volatile devices while with nonvolatile memristors, key features of a biological synapse such as short/long-term plasticity and paired pulse facilitation are emulated suggesting their potential for the development of neuromorphic circuits. These CSHSs offer an unprecedented solution for the interfacial issues between metallic electrodes and the layered materials-based switching element with the prospects of developing smaller footprint memristive devices for future integrated circuits.
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Affiliation(s)
- Renu Yadav
- Department of Physics, Indian Institute of Technology Madras, Chennai, 600036, India
- Centre for 2D Materials Research and Innovation, Indian Institute of Technology Madras, Chennai, 600036, India
| | - Saroj Poudyal
- Department of Physics, Indian Institute of Technology Madras, Chennai, 600036, India
- Centre for 2D Materials Research and Innovation, Indian Institute of Technology Madras, Chennai, 600036, India
| | - Ramesh Rajarapu
- Department of Physics, Indian Institute of Technology Madras, Chennai, 600036, India
- Centre for 2D Materials Research and Innovation, Indian Institute of Technology Madras, Chennai, 600036, India
| | - Bubunu Biswal
- Department of Physics, Indian Institute of Technology Madras, Chennai, 600036, India
- Centre for 2D Materials Research and Innovation, Indian Institute of Technology Madras, Chennai, 600036, India
| | - Prahalad Kanti Barman
- Department of Physics, Indian Institute of Technology Madras, Chennai, 600036, India
- Centre for 2D Materials Research and Innovation, Indian Institute of Technology Madras, Chennai, 600036, India
| | - S Kasiviswanathan
- Department of Physics, Indian Institute of Technology Madras, Chennai, 600036, India
| | - Kostya S Novoselov
- Institute for Functional Intelligent Materials, National University of Singapore, Singapore, 117544, Singapore
| | - Abhishek Misra
- Department of Physics, Indian Institute of Technology Madras, Chennai, 600036, India
- Centre for 2D Materials Research and Innovation, Indian Institute of Technology Madras, Chennai, 600036, India
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2
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Kim J, Lee S, Seo Y, Kim S. Emulating biological synaptic characteristics of HfOx/AlN-based 3D vertical resistive memory for neuromorphic systems. J Chem Phys 2024; 160:144703. [PMID: 38587228 DOI: 10.1063/5.0202610] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Accepted: 03/21/2024] [Indexed: 04/09/2024] Open
Abstract
Here, we demonstrate double-layer 3D vertical resistive random-access memory with a hole-type structure embedding Pt/HfOx/AlN/TiN memory cells, conduct analog resistive switching, and examine the potential of memristors for use in neuromorphic systems. The electrical characteristics, including resistive switching, retention, and endurance, of each layer are also obtained. Additionally, we investigate various synaptic characteristics, such as spike-timing dependent plasticity, spike-amplitude dependent plasticity, spike-rate dependent plasticity, spike-duration dependent plasticity, and spike-number dependent plasticity. This synapse emulation holds great potential for neuromorphic computing applications. Furthermore, potentiation and depression are manifested through identical pulses based on DC resistive switching. The pattern recognition rates within the neural network are evaluated, and based on the conductance changing linearly with incremental pulses, we achieve a pattern recognition accuracy of over 95%. Finally, the device's stability and synapse characteristics exhibit excellent potential for use in neuromorphic systems.
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Affiliation(s)
- Juri Kim
- Division of Electronics and Electrical Engineering, Dongguk University, Seoul 04620, South Korea
| | - Subaek Lee
- Division of Electronics and Electrical Engineering, Dongguk University, Seoul 04620, South Korea
| | - Yeongkyo Seo
- Department of Information and Communication Engineering, Inha University, Incheon 22212, Republic of Korea
| | - Sungjun Kim
- Division of Electronics and Electrical Engineering, Dongguk University, Seoul 04620, South Korea
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3
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Ardra M, Gayathri R, Swetha SV, Mohamed Imran P, Nagarajan S. Tweaking the Non-Volatile Write-Once-Read-Many-Times (WORM) Memory using Donor-Acceptor Architecture with Isatin as Core Acceptor. Chempluschem 2024:e202400018. [PMID: 38446710 DOI: 10.1002/cplu.202400018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Revised: 03/04/2024] [Accepted: 03/06/2024] [Indexed: 03/08/2024]
Abstract
Organic memory devices have attracted attention because they promise flexible electronics, low manufacturing costs, and compatibility with large-scale integration. A series of new D-A architectures were synthesized employing different donor groups and the isatin moiety as the acceptor through Suzuki-Miyaura coupling reactions. Strong intramolecular interactions were observed in the synthesized compounds, further corroborated by an optimal bandgap. The SEM investigation confirmed good molecular ordering and superior thin film surface coverage. All the compounds demonstrated notable binary Write-Once-Read-Many-Times (WORM) memory behaviour. The threshold switching voltage for these D-A systems ranged from -0.79 to -2.37 V, with the compound having isobutyl substituent showing the lowest threshold voltage and maximum ON/OFF ratio of 102, thus outperforming others. The combined effects of charge transfer and charge trapping are responsible for the resistive switching mechanism prevailing in these systems. The alterations in D-A molecules that affect molecular packing, thin film morphology, and, finally, the memory performance of the active layer are highlighted in this work.
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Affiliation(s)
- Murali Ardra
- Organic Electronics Division, Department of Chemistry, Central University of Tamil Nadu, Thiruvarur, 610005, India
| | - Ramesh Gayathri
- Organic Electronics Division, Department of Chemistry, Central University of Tamil Nadu, Thiruvarur, 610005, India
| | - Senthilkumar V Swetha
- Organic Electronics Division, Department of Chemistry, Central University of Tamil Nadu, Thiruvarur, 610005, India
| | | | - Samuthira Nagarajan
- Organic Electronics Division, Department of Chemistry, Central University of Tamil Nadu, Thiruvarur, 610005, India
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4
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Birara S, Saini S, Majumder M, Lama P, Tiwari SP, Metre RK. Design and synthesis of a solution-processed redox-active bis(formazanate) zinc complex for resistive switching applications. Dalton Trans 2023. [PMID: 38009276 DOI: 10.1039/d3dt02809g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2023]
Abstract
In this paper, we report the synthesis and characterization of a mononuclear zinc complex (1) containing a redox-active bis(4-antipyrinyl) derivative of the 3-cyanoformazanate ligand. Complex 1 was readily obtained by refluxing zinc acetate with 3-cyano-1,5-(4-antipyrinyl)formazan (LH) in a methanolic solution. Single-crystal X-ray diffraction analysis of complex 1 shows that the formazanate ligands bind to the zinc center in a five-member chelate "open" form via the 1- and 4-positions of the 1,2,4,5-tetraazapentadienyl formazanate backbone leading to the formation of the mononuclear bis(formazanate) zinc complex exhibiting a distorted octahedral geometry. We also report the study of resistive-switching random access memory application of this solution-processable bis(formazanate) Zn(II) complex to facilitate the practical implementation of transition metal complex-based molecular memory devices. The complex demonstrated high conductance switching with a large ON-OFF ratio, good stability, and a long retention time. A trap-controlled space charge limited current mechanism is proposed for the observed resistive switching behavior of the device, wherein the role played by the [ZnIIL2] complex that comprises the extended redox-active conjugated ligand backbone is revealed by corroborating electrochemical studies, spectrochemical experiments, and DFT calculations. In addition to providing significant insights into the molecular design of transition metal complexes for memory applications, this study also presents the utilization of ZnIIL2 towards the realization of non-volatile resistive random access memory (RRAM) devices with inorganic/organic hybrid active layers that are highly cost-effective and sustainable. These devices exhibited multilevel switching and low current operation, both of which are desirable for advanced memory applications.
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Affiliation(s)
- Sunita Birara
- Department of Chemistry, Indian Institute of Technology Jodhpur, Rajasthan-342030, India.
| | - Shalu Saini
- Department of Electrical Engineering, Indian Institute of Technology Jodhpur, Rajasthan-342030, India.
| | - Moumita Majumder
- Department of Metallurgical and Materials Engineering, Indian Institute of Technology Jodhpur, Rajasthan-342030, India.
| | - Prem Lama
- CSIR-Indian Institute of Petroleum, Haridwar Road, Mokhampur, Dehradun-248005, India
| | - Shree Prakash Tiwari
- Department of Electrical Engineering, Indian Institute of Technology Jodhpur, Rajasthan-342030, India.
| | - Ramesh K Metre
- Department of Chemistry, Indian Institute of Technology Jodhpur, Rajasthan-342030, India.
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5
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Pyo J, Jang J, Ju D, Lee S, Shim W, Kim S. Amorphous BN-Based Synaptic Device with High Performance in Neuromorphic Computing. MATERIALS (BASEL, SWITZERLAND) 2023; 16:6698. [PMID: 37895680 PMCID: PMC10608025 DOI: 10.3390/ma16206698] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 10/13/2023] [Accepted: 10/14/2023] [Indexed: 10/29/2023]
Abstract
The von Neumann architecture has faced challenges requiring high-fulfillment levels due to the performance gap between its processor and memory. Among the numerous resistive-switching random-access memories, the properties of hexagonal boron nitride (BN) have been extensively reported, but those of amorphous BN have been insufficiently explored for memory applications. Herein, we fabricated a Pt/BN/TiN device utilizing the resistive switching mechanism to achieve synaptic characteristics in a neuromorphic system. The switching mechanism is investigated based on the I-V curves. Utilizing these characteristics, we optimize the potentiation and depression to mimic the biological synapse. In artificial neural networks, high-recognition rates are achieved using linear conductance updates in a memristor device. The short-term memory characteristics are investigated in depression by controlling the conductance level and time interval.
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Affiliation(s)
- Juyeong Pyo
- Division of Electronics and Electrical Engineering, Dongguk University, Seoul 04620, Republic of Korea
| | - Junwon Jang
- Division of Electronics and Electrical Engineering, Dongguk University, Seoul 04620, Republic of Korea
| | - Dongyeol Ju
- Division of Electronics and Electrical Engineering, Dongguk University, Seoul 04620, Republic of Korea
| | - Subaek Lee
- Division of Electronics and Electrical Engineering, Dongguk University, Seoul 04620, Republic of Korea
| | - Wonbo Shim
- Department of Electrical and Information Engineering, Seoul National University of Science and Technology, Seoul 01811, Republic of Korea
| | - Sungjun Kim
- Division of Electronics and Electrical Engineering, Dongguk University, Seoul 04620, Republic of Korea
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6
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R RT, Das RR, Reghuvaran C, James A. Graphene-based RRAM devices for neural computing. Front Neurosci 2023; 17:1253075. [PMID: 37886675 PMCID: PMC10598392 DOI: 10.3389/fnins.2023.1253075] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Accepted: 09/13/2023] [Indexed: 10/28/2023] Open
Abstract
Resistive random access memory is very well known for its potential application in in-memory and neural computing. However, they often have different types of device-to-device and cycle-to-cycle variability. This makes it harder to build highly accurate crossbar arrays. Traditional RRAM designs make use of various filament-based oxide materials for creating a channel that is sandwiched between two electrodes to form a two-terminal structure. They are often subjected to mechanical and electrical stress over repeated read-and-write cycles. The behavior of these devices often varies in practice across wafer arrays over these stresses when fabricated. The use of emerging 2D materials is explored to improve electrical endurance, long retention time, high switching speed, and fewer power losses. This study provides an in-depth exploration of neuro-memristive computing and its potential applications, focusing specifically on the utilization of graphene and 2D materials in RRAM for neural computing. The study presents a comprehensive analysis of the structural and design aspects of graphene-based RRAM, along with a thorough examination of commercially available RRAM models and their fabrication techniques. Furthermore, the study investigates the diverse range of applications that can benefit from graphene-based RRAM devices.
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Affiliation(s)
| | | | | | - Alex James
- Digital University, Thiruvananthapuram, Kerala, India
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7
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Gao D, Xie X, Wei D. A Design Methodology for Fault-Tolerant Neuromorphic Computing Using Bayesian Neural Network. MICROMACHINES 2023; 14:1840. [PMID: 37893277 PMCID: PMC10608997 DOI: 10.3390/mi14101840] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 09/22/2023] [Accepted: 09/25/2023] [Indexed: 10/29/2023]
Abstract
Memristor crossbar arrays are a promising platform for neuromorphic computing. In practical scenarios, the synapse weights represented by the memristors for the underlying system are subject to process variations, in which the programmed weight when read out for inference is no longer deterministic but a stochastic distribution. It is therefore highly desired to learn the weight distribution accounting for process variations, to ensure the same inference performance in memristor crossbar arrays as the design value. In this paper, we introduce a design methodology for fault-tolerant neuromorphic computing using a Bayesian neural network, which combines the variational Bayesian inference technique with a fault-aware variational posterior distribution. The proposed framework based on Bayesian inference incorporates the impacts of memristor deviations into algorithmic training, where the weight distributions of neural networks are optimized to accommodate uncertainties and minimize inference degradation. The experimental results confirm the capability of the proposed methodology to tolerate both process variations and noise, while achieving more robust computing in memristor crossbar arrays.
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Affiliation(s)
- Di Gao
- The School of Intelligent Manufacturing, Hangzhou Polytechnic, Hangzhou 311402, China;
| | - Xiaoru Xie
- The School of Electronic Science and Engineering, Nanjing University, Nanjing 210023, China
| | - Dongxu Wei
- The College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou 310027, China
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8
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Swoboda T, Gao X, Rosário CMM, Hui F, Zhu K, Yuan Y, Deshmukh S, Köroǧlu Ç, Pop E, Lanza M, Hilgenkamp H, Rojo MM. Spatially-Resolved Thermometry of Filamentary Nanoscale Hot Spots in TiO 2 Resistive Random Access Memories to Address Device Variability. ACS APPLIED ELECTRONIC MATERIALS 2023; 5:5025-5031. [PMID: 37779889 PMCID: PMC10537448 DOI: 10.1021/acsaelm.3c00782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Accepted: 08/14/2023] [Indexed: 10/03/2023]
Abstract
Resistive random access memories (RRAM), based on the formation and rupture of conductive nanoscale filaments, have attracted increased attention for application in neuromorphic and in-memory computing. However, this technology is, in part, limited by its variability, which originates from the stochastic formation and extreme heating of its nanoscale filaments. In this study, we used scanning thermal microscopy (SThM) to assess the effect of filament-induced heat spreading on the surface of metal oxide RRAMs with different device designs. We evaluate the variability of TiO2 RRAM devices with area sizes of 2 × 2 and 5 × 5 μm2. Electrical characterization shows that the variability indicated by the standard deviation of the forming voltage is ∼2 times larger for 5 × 5 μm2 devices than for the 2 × 2 μm2 ones. Further knowledge on the reason for this variability is gained through the SThM thermal maps. These maps show that for 2 × 2 μm2 devices the formation of one filament, i.e., hot spot at the device surface, happens reliably at the same location, while the filament location varies for the 5 × 5 μm2 devices. The thermal information, combined with the electrical, interfacial, and geometric characteristics of the device, provides additional insights into the operation and variability of RRAMs. This work suggests thermal engineering and characterization routes to optimize the efficiency and reliability of these devices.
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Affiliation(s)
- Timm Swoboda
- Department
of Thermal and Fluid Engineering, Faculty of Engineering Technology, University of Twente, Enschede 7500 AE, The Netherlands
| | - Xing Gao
- Faculty
of Science and Technology and MESA+ Institute for Nanotechnology, University of Twente, Enschede 7500 AE, The Netherlands
| | - Carlos M. M. Rosário
- Faculty
of Science and Technology and MESA+ Institute for Nanotechnology, University of Twente, Enschede 7500 AE, The Netherlands
| | - Fei Hui
- School
of Materials Science and Engineering, Zhengzhou
University, Zhengzhou 450001, China
| | - Kaichen Zhu
- MIND,
Department of Electronic and Biomedical Engineering, Universitat de Barcelona, Barcelona 08007, Spain
| | - Yue Yuan
- Materials
Science and Engineering Program, Physical Science and Engineering
Division, King Abdullah University of Science
and Technology (KAUST), Thuwal 23955-6900, Saudi
Arabia
| | - Sanchit Deshmukh
- Department
of Electrical Engineering, Stanford University, Stanford, California 94305, United States
| | - Çaǧıl Köroǧlu
- Department
of Electrical Engineering, Stanford University, Stanford, California 94305, United States
| | - Eric Pop
- Department
of Electrical Engineering, Stanford University, Stanford, California 94305, United States
- Department
of Materials Science and Engineering, Stanford
University, Stanford, California 94305, United States
- Precourt
Institute for Energy, Stanford University, Stanford, California 94305, United States
| | - Mario Lanza
- Materials
Science and Engineering Program, Physical Science and Engineering
Division, King Abdullah University of Science
and Technology (KAUST), Thuwal 23955-6900, Saudi
Arabia
| | - Hans Hilgenkamp
- Faculty
of Science and Technology and MESA+ Institute for Nanotechnology, University of Twente, Enschede 7500 AE, The Netherlands
| | - Miguel Muñoz Rojo
- Department
of Thermal and Fluid Engineering, Faculty of Engineering Technology, University of Twente, Enschede 7500 AE, The Netherlands
- 2D
Foundry,
Instituto de Ciencia de Materiales de Madrid (ICMM), CSIC, Madrid 28049, Spain
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9
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Aldana S, Zhang H. Unravelling the Data Retention Mechanisms under Thermal Stress on 2D Memristors. ACS OMEGA 2023; 8:27543-27552. [PMID: 37546646 PMCID: PMC10398860 DOI: 10.1021/acsomega.3c03200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Accepted: 07/07/2023] [Indexed: 08/08/2023]
Abstract
Memristors based on two-dimensional (2D) materials are a rapidly growing research area due to their potential in energy-efficient in-memory processing and neuromorphic computing. However, the data retention of these emerging memristors remains sparsely investigated, despite its crucial importance to device performance and reliability. In this study, we employ kinetic Monte-Carlo simulations to investigate the data retention of a 2D planar memristor. The operation of the memristor depends on field-driven on defect migration, while thermal diffusion gradually evens the defect distribution, leading to the degradation of the high resistance state (HRS) and diminishing the ON/OFF ratio. Notably, we examine the resilience of devices based on single crystals of transition metal dichalcogenides (TMDs) in harsh environments. Specifically, our simulations show that MoS2-based devices have negligible degradation after 10 years of thermal annealing at 400 K. Furthermore, the variability in data retention lifetime across different temperatures is less than 22%, indicating a relatively consistent performance over a range of thermal conditions. We also demonstrate that device miniaturization does not compromise data retention lifetime. Moreover, employing materials with higher activation energy for defect migration can significantly enhance data retention at the cost of increased switching voltage. These findings shed light on the behavior of 2D memristors and pave the way for their optimization in practical applications.
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Affiliation(s)
- Samuel Aldana
- Centre
for Research on Adaptive Nanostructures and Nanodevices (CRANN) and
Advanced Materials and Bioengineering Research (AMBER) Research Centers, Trinity College Dublin, Dublin D02 PN40, Ireland
- School
of Physics, Trinity College Dublin, Dublin D02 PN40, Ireland
| | - Hongzhou Zhang
- Centre
for Research on Adaptive Nanostructures and Nanodevices (CRANN) and
Advanced Materials and Bioengineering Research (AMBER) Research Centers, Trinity College Dublin, Dublin D02 PN40, Ireland
- School
of Physics, Trinity College Dublin, Dublin D02 PN40, Ireland
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10
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Zahoor F, Hussin FA, Isyaku UB, Gupta S, Khanday FA, Chattopadhyay A, Abbas H. Resistive random access memory: introduction to device mechanism, materials and application to neuromorphic computing. DISCOVER NANO 2023; 18:36. [PMID: 37382679 PMCID: PMC10409712 DOI: 10.1186/s11671-023-03775-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2022] [Accepted: 01/17/2023] [Indexed: 06/30/2023]
Abstract
The modern-day computing technologies are continuously undergoing a rapid changing landscape; thus, the demands of new memory types are growing that will be fast, energy efficient and durable. The limited scaling capabilities of the conventional memory technologies are pushing the limits of data-intense applications beyond the scope of silicon-based complementary metal oxide semiconductors (CMOS). Resistive random access memory (RRAM) is one of the most suitable emerging memory technologies candidates that have demonstrated potential to replace state-of-the-art integrated electronic devices for advanced computing and digital and analog circuit applications including neuromorphic networks. RRAM has grown in prominence in the recent years due to its simple structure, long retention, high operating speed, ultra-low-power operation capabilities, ability to scale to lower dimensions without affecting the device performance and the possibility of three-dimensional integration for high-density applications. Over the past few years, research has shown RRAM as one of the most suitable candidates for designing efficient, intelligent and secure computing system in the post-CMOS era. In this manuscript, the journey and the device engineering of RRAM with a special focus on the resistive switching mechanism are detailed. This review also focuses on the RRAM based on two-dimensional (2D) materials, as 2D materials offer unique electrical, chemical, mechanical and physical properties owing to their ultrathin, flexible and multilayer structure. Finally, the applications of RRAM in the field of neuromorphic computing are presented.
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Affiliation(s)
- Furqan Zahoor
- School of Computer Science and Engineering, Nanyang Technological University, Singapore, Singapore
| | - Fawnizu Azmadi Hussin
- Department of Electrical and Electronics Engineering, Universiti Teknologi Petronas, Seri Iskandar, Malaysia
| | - Usman Bature Isyaku
- Department of Electrical and Electronics Engineering, Universiti Teknologi Petronas, Seri Iskandar, Malaysia
| | - Shagun Gupta
- School of Electronics and Communication Engineering, Shri Mata Vaishno Devi University, Katra, India
| | - Farooq Ahmad Khanday
- Department of Electronics & Instrumentation Technology, University of Kashmir, Srinagar, India
| | - Anupam Chattopadhyay
- School of Computer Science and Engineering, Nanyang Technological University, Singapore, Singapore
| | - Haider Abbas
- Division of Material Science and Engineering, Hanyang University, Seoul, South Korea
- School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore, Singapore
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11
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Lanza M, Hui F, Wen C, Ferrari AC. Resistive Switching Crossbar Arrays Based on Layered Materials. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2205402. [PMID: 36094019 DOI: 10.1002/adma.202205402] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Revised: 08/25/2022] [Indexed: 06/15/2023]
Abstract
Resistive switching (RS) devices are metal/insulator/metal cells that can change their electrical resistance when electrical stimuli are applied between the electrodes, and they can be used to store and compute data. Planar crossbar arrays of RS devices can offer a high integration density (>108 devices mm- 2 ) and this can be further enhanced by stacking them three-dimensionally. The advantage of using layered materials (LMs) in RS devices compared to traditional phase-change materials and metal oxides is that their electrical properties can be adjusted with a higher precision. Here, the key figures-of-merit and procedures to implement LM-based RS devices are defined. LM-based RS devices fabricated using methods compatible with industry are identified and discussed. The focus is on small devices (size < 9 µm2 ) arranged in crossbar structures, since larger devices may be affected by artifacts, such as grain boundaries and flake junctions. How to enhance device performance, so to accelerate the development of this technology, is also discussed.
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Affiliation(s)
- Mario Lanza
- Physical Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Fei Hui
- School of Materials Science and Engineering, The Key Laboratory of Material, Processing and Mold of the Ministry of Education, Henan Key Laboratory of Advanced, Nylon Materials and Application, Zhengzhou University, Zhengzhou, 450001, P. R. China
| | - Chao Wen
- Cambridge Graphene Centre, University of Cambridge, Cambridge, CB3 0FA, UK
| | - Andrea C Ferrari
- Cambridge Graphene Centre, University of Cambridge, Cambridge, CB3 0FA, UK
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12
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Betal A, Bera J, Sharma A, Rath AK, Sahu S. Charge trapped CdS quantum dot embedded polymer matrix for a high speed and low power memristor. Phys Chem Chem Phys 2023; 25:3737-3744. [PMID: 36683490 DOI: 10.1039/d2cp05014e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The data storage requirement in the digital world is increasing day by day with the advancement of the internet of things. In this respect, nonvolatile resistive random-access memory is an option that provides high density and low power data storage capabilities. In this work, zero-dimensional colloidal CdS quantum dots and a polymer composite at an appropriate ratio were used to fabricate a memristive device. Comparison with a pristine CdS quantum dot-based device reveals that a surrounding matrix around the quantum dots is needed for observing memristive behavior. The quantum dots embedded in the polymer matrix device showed extremely stable electrical switching behavior that can be operated for more than 300 cycles and 60 000 seconds. Moreover, the device needs extremely low power to operate at a very high speed. The smooth surface morphology dictates a charge trapping mechanism for the switching phenomenon; however, an interplay between different charge transport mechanisms leads to the fast switching and high on-off ratio of the device.
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Affiliation(s)
- Atanu Betal
- Indian Institute of Technology Jodhpur, Department of Physics, Jodhpur, 342037, India.
| | - Jayanta Bera
- Indian Institute of Technology Jodhpur, Department of Physics, Jodhpur, 342037, India.
| | - Ashish Sharma
- Council of Scientific and Industrial Research, National Chemical Laboratory, Pune, 411008, India.,Academy of Scientific and Innovative Research, Ghaziabad, 201002, India
| | - Arup K Rath
- Council of Scientific and Industrial Research, National Chemical Laboratory, Pune, 411008, India.,Academy of Scientific and Innovative Research, Ghaziabad, 201002, India
| | - Satyajit Sahu
- Indian Institute of Technology Jodhpur, Department of Physics, Jodhpur, 342037, India.
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Baranowski M, Sachser R, Marinković BP, Ivanović SD, Huth M. Charge Transport inside TiO 2 Memristors Prepared via FEBID. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:nano12234145. [PMID: 36500769 PMCID: PMC9740258 DOI: 10.3390/nano12234145] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Revised: 11/15/2022] [Accepted: 11/18/2022] [Indexed: 05/27/2023]
Abstract
We fabricated memristive devices using focused electron beam-induced deposition (FEBID) as a direct-writing technique employing a Pt/TiO2/Pt sandwich layer device configuration. Pinching in the measured current-voltage characteristics (i-v), the characteristic fingerprint of memristive behavior was clearly observed. The temperature dependence was measured for both high and low resistive states in the range from 290 K down to about 2 K, showing a stretched exponential behavior characteristic of Mott-type variable-range hopping. From this observation, a valence change mechanism of the charge transport inside the TiO2 layer can be deduced.
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Affiliation(s)
- Markus Baranowski
- Physikalisches Institut, Goethe University, 60438 Frankfurt am Main, Germany
| | - Roland Sachser
- Physikalisches Institut, Goethe University, 60438 Frankfurt am Main, Germany
| | - Bratislav P. Marinković
- Institute of Physics Belgrade, University of Belgrade, Pregrevica 118, 11080 Belgrade, Serbia
| | - Stefan Dj. Ivanović
- Institute of Physics Belgrade, University of Belgrade, Pregrevica 118, 11080 Belgrade, Serbia
| | - Michael Huth
- Physikalisches Institut, Goethe University, 60438 Frankfurt am Main, Germany
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14
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Avila LB, Serrano Arambulo PC, Dantas A, Cuevas-Arizaca EE, Kumar D, Müller CK. Study on the Electrical Conduction Mechanism of Unipolar Resistive Switching Prussian White Thin Films. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:2881. [PMID: 36014746 PMCID: PMC9416141 DOI: 10.3390/nano12162881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Revised: 08/04/2022] [Accepted: 08/10/2022] [Indexed: 06/15/2023]
Abstract
The electrical conduction mechanism of resistive switching Prussian white (PW) thin films obtained by the electrodeposition method was examined by AC impedance spectroscopy and DC current-voltage measurements. Using an electrode tip to contact PW grown over Au, robust unipolar resistive switching was observed with a current change of up to three orders of magnitude, high repeatability, and reproducibility. Moreover, electrical impedance spectroscopy showed that the resistive switching comes from small conductive filaments formed by potassium ions before the establishment of larger conductive channels. Both voltammetry and EIS measurements suggest that the electrical properties and conductive filament formation are influenced by defects and ions present in the grain boundaries. Thus, PW is a potential material for the next generation of ReRAM devices.
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Affiliation(s)
- Lindiomar B. Avila
- Departamento de Física, Universidade Federal de Santa Catarina, Florianópolis 88040-900, Santa Catarina, Brazil
| | - Pablo C. Serrano Arambulo
- Departamento de Física, Universidade Federal de Santa Catarina, Florianópolis 88040-900, Santa Catarina, Brazil
| | - Adriana Dantas
- Department of Chemical and Food Engineering, Federal University of Santa Catarina, Florianopolis 88040-900, Santa Catarina, Brazil
| | | | - Dinesh Kumar
- Shoolini University of Biotechnology and Management Sciences, Solan 173229, India
| | - Christian K. Müller
- Faculty of Physical Engineering/Computer Sciences, University of Applied Sciences Zwickau, 08056 Zwickau, Germany
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15
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All-Printed Flexible Memristor with Metal–Non-Metal-Doped TiO2 Nanoparticle Thin Films. NANOMATERIALS 2022; 12:nano12132289. [PMID: 35808124 PMCID: PMC9268177 DOI: 10.3390/nano12132289] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Revised: 06/29/2022] [Accepted: 06/30/2022] [Indexed: 01/17/2023]
Abstract
A memristor is a fundamental electronic device that operates like a biological synapse and is considered as the solution of classical von Neumann computers. Here, a fully printed and flexible memristor is fabricated by depositing a thin film of metal–non-metal (chromium-nitrogen)-doped titanium dioxide (TiO2). The resulting device exhibited enhanced performance with self-rectifying and forming free bipolar switching behavior. Doping was performed to bring stability in the performance of the memristor by controlling the defects and impurity levels. The forming free memristor exhibited characteristic behavior of bipolar resistive switching with a high on/off ratio (2.5 × 103), high endurance (500 cycles), long retention time (5 × 103 s) and low operating voltage (±1 V). Doping the thin film of TiO2 with metal–non-metal had a significant effect on the switching properties and conduction mechanism as it directly affected the energy bandgap by lowering it from 3.2 eV to 2.76 eV. Doping enhanced the mobility of charge carriers and eased the process of filament formation by suppressing its randomness between electrodes under the applied electric field. Furthermore, metal–non-metal-doped TiO2 thin film exhibited less switching current and improved non-linearity by controlling the surface defects.
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16
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Pam ME, Li S, Su T, Chien YC, Li Y, Ang YS, Ang KW. Interface-Modulated Resistive Switching in Mo-Irradiated ReS 2 for Neuromorphic Computing. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2202722. [PMID: 35610176 DOI: 10.1002/adma.202202722] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Revised: 04/30/2022] [Indexed: 06/15/2023]
Abstract
Coupling charge impurity scattering effects and charge-carrier modulation by doping can offer intriguing opportunities for atomic-level control of resistive switching (RS). Nonetheless, such effects have remained unexplored for memristive applications based on 2D materials. Here a facile approach is reported to transform an RS-inactive rhenium disulfide (ReS2 ) into an effective switching material through interfacial modulation induced by molybdenum-irradiation (Mo-i) doping. Using ReS2 as a model system, this study unveils a unique RS mechanism based on the formation/dissolution of metallic β-ReO2 filament across the defective ReS2 interface during the set/reset process. Through simple interfacial modulation, ReS2 of various thicknesses are switchable by modulating the Mo-irradiation period. Besides, the Mo-irradiated ReS2 (Mo-ReS2 ) memristor further exhibits a bipolar non-volatile switching ratio of nearly two orders of magnitude, programmable multilevel resistance states, and long-term synaptic plasticity. Additionally, the fabricated device can achieve a high MNIST learning accuracy of 91% under a non-identical pulse train. The study's findings demonstrate the potential for modulating RS in RS-inactive 2D materials via the unique doping-induced charged impurity scattering property.
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Affiliation(s)
- Mei Er Pam
- Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore, 117583, Singapore
| | - Sifan Li
- Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore, 117583, Singapore
| | - Tong Su
- Science, Mathematics and Technology (SMT), Singapore University of Technology and Design (SUTD), 8 Somapah Road, Singapore, 487372, Singapore
| | - Yu-Chieh Chien
- Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore, 117583, Singapore
| | - Yesheng Li
- Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore, 117583, Singapore
| | - Yee Sin Ang
- Science, Mathematics and Technology (SMT), Singapore University of Technology and Design (SUTD), 8 Somapah Road, Singapore, 487372, Singapore
| | - Kah-Wee Ang
- Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore, 117583, Singapore
- Institute of Materials Research and Engineering, A*STAR, 2 Fusionopolis, Singapore, 138634, Singapore
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17
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Batool S, Idrees M, Zhang SR, Han ST, Zhou Y. Novel charm of 2D materials engineering in memristor: when electronics encounter layered morphology. NANOSCALE HORIZONS 2022; 7:480-507. [PMID: 35343522 DOI: 10.1039/d2nh00031h] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The family of two-dimensional (2D) materials composed of atomically thin layers connected via van der Waals interactions has attracted much curiosity due to a variety of intriguing physical, optical, and electrical characteristics. The significance of analyzing statistics on electrical devices and circuits based on 2D materials is seldom underestimated. Certain requirements must be met to deliver scientific knowledge that is beneficial in the field of 2D electronics: synthesis and fabrication must occur at the wafer level, variations in morphology and lattice alterations must be visible and statistically verified, and device dimensions must be appropriate. The authors discussed the most recent significant concerns of 2D materials in the provided prose and attempted to highlight the prerequisites for synthesis, yield, and mechanism behind device-to-device variability, reliability, and durability benchmarking under memristors characteristics; they also indexed some useful approaches that have already been reported to be advantageous in large-scale production. Commercial applications, on the other hand, will necessitate further effort.
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Affiliation(s)
- Saima Batool
- Institute for Advanced Study, Shenzhen University, Shenzhen, 518060, P. R. China.
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, Institute of Microscale Optoelectronics, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen, 518060, P. R. China
| | - Muhammad Idrees
- Additive Manufacturing Institute, College of Mechatronics and Control Engineering, Shenzhen University, Shenzhen 518060, P. R. China
| | - Shi-Rui Zhang
- Department of Electronic Materials Engineering, Research School of Physics, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Su-Ting Han
- College of Electronics Science & Technology, Shenzhen University, Shenzhen, 518060, P. R. China
| | - Ye Zhou
- Institute for Advanced Study, Shenzhen University, Shenzhen, 518060, P. R. China.
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18
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Zhang W, Lei J, Dai Y, Zhang X, Kang L, Peng B, Hu F. Switching-behavior improvement in HfO 2/ZnO bilayer memory devices by tailoring of interfacial and microstructural characteristics. NANOTECHNOLOGY 2022; 33:255703. [PMID: 35294938 DOI: 10.1088/1361-6528/ac5e70] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Accepted: 03/16/2022] [Indexed: 06/14/2023]
Abstract
We investigated the effect of top contact interface and microstructural characteristics of the insulating layers on resistive switching behaviors by fabricating and characterizing the HfO2/ZnO bilayer heterostructures. Different thickness of ZnO underlying layer and different deposition temperatures of the upper HfO2layer were designed to analyze the intrinsic contribution of the crystalline microstructure of the insulating bilayer. Pt and Ti top electrodes were used to demonstrate the extrinsic contribution of the interface configuration. It was observed that all devices show bipolar RS characteristics. Unlike the device composed of Pt/HfO2/ZnO/Pt that exhibit an abrupt switching, a gradually continuous switching in the reset process was identified in the device composed of Ti/HfO2/ZnO/Pt. Interfacial charge migration process/characteristic plays a key role in the RS process as well as its conduction mechanism. The RS performance of the former is significantly better than that of the latter, including much lower reset voltage, two orders of magnitude larger OFF/ON ratio and HRS resistance. In addition, as compared to the intrinsic contribution arising from the microstructure of the HfO2/ZnO bilayer to the RS performances and current transport mechanism, the extrinsic effect contributed from the electrode characteristics (and its interface) is dominant.
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Affiliation(s)
- Wei Zhang
- College of Electronic and Optical Engineering, Nanjing University of Posts and Telecommunications, Nanjing 210023, People's Republic of China
| | - Jianzhang Lei
- College of Electronic and Optical Engineering, Nanjing University of Posts and Telecommunications, Nanjing 210023, People's Republic of China
| | - Yixian Dai
- College of Electronic and Optical Engineering, Nanjing University of Posts and Telecommunications, Nanjing 210023, People's Republic of China
| | - Xuehua Zhang
- College of Electronic and Optical Engineering, Nanjing University of Posts and Telecommunications, Nanjing 210023, People's Republic of China
| | - Limin Kang
- School of Chemical Engineering, Nanjing University of Science and Technology, Nanjing 210094, People's Republic of China
| | - Bowen Peng
- College of Electronic and Optical Engineering, Nanjing University of Posts and Telecommunications, Nanjing 210023, People's Republic of China
| | - Fangren Hu
- College of Electronic and Optical Engineering, Nanjing University of Posts and Telecommunications, Nanjing 210023, People's Republic of China
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19
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Lian H, Cheng X, Hao H, Han J, Lau MT, Li Z, Zhou Z, Dong Q, Wong WY. Metal-containing organic compounds for memory and data storage applications. Chem Soc Rev 2022; 51:1926-1982. [PMID: 35083990 DOI: 10.1039/d0cs00569j] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
With the upcoming trend of Big Data era, some new types of memory technologies have emerged as substitutes for the traditional Si-based semiconductor memory devices, which are encountering severe scaling down technical obstacles. In particular, the resistance random access memory (RRAM) and magnetic random access memory (MRAM) hold great promise for the in-memory computing, which are regarded as the optimal strategy and pathway to solve the von Neumann bottleneck by high-throughput in situ data processing. As far as the active materials in RRAM and MRAM are concerned, organic semiconducting materials have shown increasing application perspectives in memory devices due to their rich structural diversity and solution processability. With the introduction of metal elements into the backbone of molecules, some new properties and phenomena will emerge accordingly. Consequently, the RRAM and MRAM devices based on metal-containing organic compounds (including the small molecular metal complexes, metallopolymers, metal-organic frameworks (MOFs) and organic-inorganic-hybrid perovskites (OIHPs)) have been widely explored and attracted intense attention. In this review, we highlight the fundamentals of RRAM and MRAM, as well as the research progress of the applications of metal-containing organic compounds in both RRAM and MRAM. Finally, we discuss the challenges and future directions for the research of organic RRAM and MRAM.
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Affiliation(s)
- Hong Lian
- MOE Key Laboratory of Advanced Display and System Applications, Shanghai University, 149 Yanchang Road, Jingan District, Shanghai 200072, China.,School of Mechanical & Electronic Engineering and Automation, Shanghai University, 99 Shangda Road, Baoshan District, Shanghai 200444, China. .,MOE Key Laboratory of Interface Science and Engineering in Advanced Materials, Taiyuan University of Technology, 79 Yingze West Street, Taiyuan, 030024, China
| | - Xiaozhe Cheng
- MOE Key Laboratory of Advanced Display and System Applications, Shanghai University, 149 Yanchang Road, Jingan District, Shanghai 200072, China.,MOE Key Laboratory of Interface Science and Engineering in Advanced Materials, Taiyuan University of Technology, 79 Yingze West Street, Taiyuan, 030024, China.,Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Hong Kong, China.
| | - Haotian Hao
- MOE Key Laboratory of Interface Science and Engineering in Advanced Materials, Taiyuan University of Technology, 79 Yingze West Street, Taiyuan, 030024, China
| | - Jinba Han
- MOE Key Laboratory of Interface Science and Engineering in Advanced Materials, Taiyuan University of Technology, 79 Yingze West Street, Taiyuan, 030024, China
| | - Mei-Tung Lau
- Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Hong Kong, China. .,The Hong Kong Polytechnic University Shenzhen Research Institute, Shenzhen 518057, China
| | - Zikang Li
- Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Hong Kong, China. .,The Hong Kong Polytechnic University Shenzhen Research Institute, Shenzhen 518057, China
| | - Zhi Zhou
- School of Chemistry and Materials Science, Hunan Agricultural University, Changsha 410128, China.
| | - Qingchen Dong
- MOE Key Laboratory of Advanced Display and System Applications, Shanghai University, 149 Yanchang Road, Jingan District, Shanghai 200072, China.,School of Mechanical & Electronic Engineering and Automation, Shanghai University, 99 Shangda Road, Baoshan District, Shanghai 200444, China. .,MOE Key Laboratory of Interface Science and Engineering in Advanced Materials, Taiyuan University of Technology, 79 Yingze West Street, Taiyuan, 030024, China
| | - Wai-Yeung Wong
- Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Hong Kong, China. .,The Hong Kong Polytechnic University Shenzhen Research Institute, Shenzhen 518057, China
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20
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Zhang Y, Wu Q, Cui J, Li C. Tunable dual-channel slow light in a graphene grating plasmonic waveguide. APPLIED OPTICS 2022; 61:345-351. [PMID: 35200868 DOI: 10.1364/ao.442912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 12/08/2021] [Indexed: 06/14/2023]
Abstract
We propose a plasmonic waveguide comprising a single-layer graphene, a silica dielectric layer, and a silicon grating substrate to realize dual-channel slow surface plasmon polaritons. The dual-channel results from the introduction of two kinds of periodic structures with defects in the waveguide. According to the Bragg equation, we match the appropriate structure parameters to ensure the slow light dual-channel working around λ1=9369.1nm (32 THz) and λ2=7138.2nm (42 THz). The influence of the structure parameters on the slow light effect is discussed, and the largest value of the normalized delay bandwidth product (NDBP) is up to 7.38. Then, by shifting the gate voltage, obvious linear blueshift of the dual-channel is achieved. In this process, the slow light performance of the dual-channel exhibits good stability, and the average values of the NDBP are 4.5 and 4.4. Due to the flexible tunability, the waveguide may pave the way for the design of slow light devices.
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21
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Andreeva N, Mazing D, Romanov A, Gerasimova M, Chigirev D, Luchinin V. Contact Engineering Approach to Improve the Linearity of Multilevel Memristive Devices. MICROMACHINES 2021; 12:mi12121567. [PMID: 34945416 PMCID: PMC8706226 DOI: 10.3390/mi12121567] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Revised: 12/10/2021] [Accepted: 12/14/2021] [Indexed: 11/16/2022]
Abstract
Physical mechanisms underlying the multilevel resistive tuning over seven orders of magnitude in structures based on TiO2/Al2O3 bilayers, sandwiched between platinum electrodes, are responsible for the nonlinear dependence of the conductivity of intermediate resistance states on the writing voltage. To improve the linearity of the electric-field resistance tuning, we apply a contact engineering approach. For this purpose, platinum top electrodes were replaced with aluminum and copper ones to induce the oxygen-related electrochemical reactions at the interface with the Al2O3 switching layer of the structures. Based on experimental results, it was found that electrode material substitution provokes modification of the physical mechanism behind the resistive switching in TiO2/Al2O3 bilayers. In the case of aluminum electrodes, a memory window has been narrowed down to three orders of magnitude, while the linearity of resistance tuning was improved. For copper electrodes, a combination of effects related to metal ion diffusion with oxygen vacancies driven resistive switching was responsible for a rapid relaxation of intermediate resistance states in TiO2/Al2O3 bilayers.
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22
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Dai Y, Yang B, Li X, Shao P, Wang X, Wang F, Ding C, Yang F. First-principles study of bipolar resistive memories based on monolayer α-GeTe. NANOTECHNOLOGY 2021; 32:475701. [PMID: 34384054 DOI: 10.1088/1361-6528/ac1d04] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Accepted: 08/11/2021] [Indexed: 06/13/2023]
Abstract
In this work, the electrical properties of monolayerα-GeTe (MLα-GeTe) based on first-principles were studied, in which armchairα-GeTe shows an ohmic current-voltage relationship and zigzagα-GeTe shows an obvious nonlinear current. The potential distribution and band structure explain the mechanism for the anisotropy and nonlinearity. Then, based on calculation of the binding energy and Mulliken population, eight interface structures between graphene (GR) and MLα-GeTe were constructed, in which GC3 and TC3 were found to be relatively stable. Next, GR/MLα-GeTe/GR was established based on the two interfaces (GC3 and TC3). The current-voltage (IV) characteristics were calculated to show that the device has bipolar resistance characteristics, suitable set and reset voltages and a high window value (104). Further analysis of electron density inferred that the resistance mechanism was based on the drift of Te vacancies forming conductive filaments. And the performance of GR/MLα-GeTe/GR was found to be improved by the creation of Te vacancies. This work indicates that GR/MLα-GeTe/GR has the potential to be used to build resistive random access memory (RRAM) with good performance and may be instructive and valuable for the manufacture and application of RRAM.
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Affiliation(s)
- Yuehua Dai
- School of Electronics and Information Engineering, Anhui University, Hefei 230000, People's Republic of China
| | - Bin Yang
- School of Electronics and Information Engineering, Anhui University, Hefei 230000, People's Republic of China
| | - Xing Li
- School of Electronics and Information Engineering, Anhui University, Hefei 230000, People's Republic of China
| | - Peng Shao
- School of Electronics and Information Engineering, Anhui University, Hefei 230000, People's Republic of China
| | - Xiaoqing Wang
- School of Electronics and Information Engineering, Anhui University, Hefei 230000, People's Republic of China
| | - Feifei Wang
- School of Electronics and Information Engineering, Anhui University, Hefei 230000, People's Republic of China
| | - Cheng Ding
- School of Electronics and Information Engineering, Anhui University, Hefei 230000, People's Republic of China
| | - Fei Yang
- School of Electronics and Information Engineering, Anhui University, Hefei 230000, People's Republic of China
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23
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Mutee Ur Rehman HM, Rehman MM, Saqib M, Ali Khan S, Khan M, Yang Y, Kim S, Rahman SA, Kim WY. Highly Efficient and Wide Range Humidity Response of Biocompatible Egg White Thin Film. NANOMATERIALS 2021; 11:nano11071815. [PMID: 34361201 PMCID: PMC8308394 DOI: 10.3390/nano11071815] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/06/2021] [Revised: 07/02/2021] [Accepted: 07/08/2021] [Indexed: 11/23/2022]
Abstract
Biopolymers are a solution to solve the increasing problems caused by the advances and revolution in the electronic industry owing to the use of hazardous chemicals. In this work, we have used egg white (EW) as the low-cost functional layer of a biocompatible humidity sensor and deposited it on gold (Au) interdigitated electrodes (IDEs) patterned through the state-of-the-art fabrication technology of thermal vacuum evaporation. The presence of hydrophilic proteins inside the thin film of EW makes it an attractive candidate for sensing humidity. Usually, the dependence of the percentage of relative humidity (%RH) on the reliability of measurement setup is overlooked for impedimetric humidity sensors but we have used a modified experimental setup to enhance the uniformity of the obtained results. The characteristics of our device include almost linear response with a quick response time (1.2 s) and fast recovery time (1.7 s). High sensitivity of 50 kΩ/%RH was achieved in the desirable detection range of 10–85%RH. The device size was intentionally kept small for its potential integration in a marketable chip. Results for the response of our fabricated sensor for dry and wet fingertips, along with determining the rate of breathing through the mouth, are part of this study, making it a potential device for health monitoring.
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Affiliation(s)
| | - Muhammad Muqeet Rehman
- Department of Electronic Engineering, Jeju National University, Jeju 63243, Korea; (M.S.); (S.A.K.); (Y.Y.); (S.K.); (S.A.R.)
- Correspondence: (M.M.R.); (W.-Y.K.)
| | - Muhammad Saqib
- Department of Electronic Engineering, Jeju National University, Jeju 63243, Korea; (M.S.); (S.A.K.); (Y.Y.); (S.K.); (S.A.R.)
| | - Shenawar Ali Khan
- Department of Electronic Engineering, Jeju National University, Jeju 63243, Korea; (M.S.); (S.A.K.); (Y.Y.); (S.K.); (S.A.R.)
| | - Maryam Khan
- Department of Electrical Engineering, GIK Institute, Topi 23460, Pakistan;
| | - Yunsook Yang
- Department of Electronic Engineering, Jeju National University, Jeju 63243, Korea; (M.S.); (S.A.K.); (Y.Y.); (S.K.); (S.A.R.)
| | - Seongwan Kim
- Department of Electronic Engineering, Jeju National University, Jeju 63243, Korea; (M.S.); (S.A.K.); (Y.Y.); (S.K.); (S.A.R.)
| | - Sheik Abdur Rahman
- Department of Electronic Engineering, Jeju National University, Jeju 63243, Korea; (M.S.); (S.A.K.); (Y.Y.); (S.K.); (S.A.R.)
| | - Woo-Young Kim
- Faculty of Applied Energy System, Major of Electronic Engineering, Jeju National University, Jeju 63243, Korea;
- Department of Electronic Engineering, Jeju National University, Jeju 63243, Korea; (M.S.); (S.A.K.); (Y.Y.); (S.K.); (S.A.R.)
- Correspondence: (M.M.R.); (W.-Y.K.)
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24
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Pang CS, Zhou R, Liu X, Wu P, Hung TYT, Guo S, Zaghloul ME, Krylyuk S, Davydov AV, Appenzeller J, Chen Z. Mobility Extraction in 2D Transition Metal Dichalcogenide Devices-Avoiding Contact Resistance Implicated Overestimation. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2021; 17:e2100940. [PMID: 34110675 PMCID: PMC9703574 DOI: 10.1002/smll.202100940] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 03/25/2021] [Indexed: 06/01/2023]
Abstract
Schottky barrier (SB) transistors operate distinctly different from conventional metal-oxide semiconductor field-effect transistors, in a unique way that the gate impacts the carrier injection from the metal source/drain contacts into the channel region. While it has been long recognized that this can have severe implications for device characteristics in the subthreshold region, impacts of contact gating of SB in the on-state of the devices, which affects evaluation of intrinsic channel properties, have been yet comprehensively studied. Due to the fact that contact resistance (RC ) is always gate-dependent in a typical back-gated device structure, the traditional approach of deriving field-effect mobility from the maximum transconductance (gm ) is in principle not correct and can even overestimate the mobility. In addition, an exhibition of two different threshold voltages for the channel and the contact region leads to another layer of complexity in determining the true carrier concentration calculated from Q = COX * (VG -VTH ). Through a detailed experimental analysis, the effect of different effective oxide thicknesses, distinct SB heights, and doping-induced reductions in the SB width are carefully evaluated to gain a better understanding of their impact on important device metrics.
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Affiliation(s)
- Chin-Sheng Pang
- Birck Nanotechnology Center, Department of Electrical and Computer Engineering, Purdue University, 1205 W State St, West Lafayette, IN, 47907, USA
| | - Ruiping Zhou
- Birck Nanotechnology Center, Department of Electrical and Computer Engineering, Purdue University, 1205 W State St, West Lafayette, IN, 47907, USA
| | - Xiangkai Liu
- Birck Nanotechnology Center, Department of Electrical and Computer Engineering, Purdue University, 1205 W State St, West Lafayette, IN, 47907, USA
| | - Peng Wu
- Birck Nanotechnology Center, Department of Electrical and Computer Engineering, Purdue University, 1205 W State St, West Lafayette, IN, 47907, USA
| | - Terry Y T Hung
- Birck Nanotechnology Center, Department of Electrical and Computer Engineering, Purdue University, 1205 W State St, West Lafayette, IN, 47907, USA
| | - Shiqi Guo
- School of Engineering and Applied Science, The George Washington University, Washington, DC, 20052, USA
| | - Mona E Zaghloul
- School of Engineering and Applied Science, The George Washington University, Washington, DC, 20052, USA
| | - Sergiy Krylyuk
- Materials Science and Engineering Division, National Institute of Standards and Technology (NIST), Gaithersburg, MD, 20899, USA
| | - Albert V Davydov
- Materials Science and Engineering Division, National Institute of Standards and Technology (NIST), Gaithersburg, MD, 20899, USA
| | - Joerg Appenzeller
- Birck Nanotechnology Center, Department of Electrical and Computer Engineering, Purdue University, 1205 W State St, West Lafayette, IN, 47907, USA
| | - Zhihong Chen
- Birck Nanotechnology Center, Department of Electrical and Computer Engineering, Purdue University, 1205 W State St, West Lafayette, IN, 47907, USA
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Kumari A, Shanbogh SM, Udachyan I, Kandaiah S, Roy A, Varade V, Ponnam A. Interface-Driven Multifunctionality in Two-Dimensional TiO 2 Nanosheet/Poly(Dimercaptothiadiazole-Triazine) Hybrid Resistive Random Access Memory Device. ACS APPLIED MATERIALS & INTERFACES 2020; 12:56568-56578. [PMID: 33283514 DOI: 10.1021/acsami.0c16451] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Interface-driven multifunctional facets are gearing up in the field of science and technology. Here, we present the interface-activated resistive switching (RS), negative differential resistance, diode behavior, and ultraviolet (UV) light sensing in nanosheet-based hybrid devices. A hybrid device i.e., titanium dioxide nanosheet (TiO2-NS)/poly(dimercaptothiadiazole-triazine)[Poly(DMcT-CC)] is fabricated by spin coating Poly(DMcT-CC) polymer on hydrothermally as-grown TiO2-NS. The pristine devices of both materials show either small or no magnitude of RS, but the hybrid device shows highly enhanced RS of nearly four orders due to the formation of a p-n junction at the NS/polymer interface. The resistive random access memory feature appears to be more prominent in the hybrid device i.e., high and low current states are found to be stable in repetitive cycles since the interface acts as a trapping center for the carriers. The UV sensing ability of the hybrid device has been demonstrated by a threefold increment in a current at 60 mV. The impedance spectroscopy has been employed to show that the multifunctional features are directly associated to the NS/polymer interface, which deduce that the manipulation of such interfaces can pave the way for developing the hybrid structures.
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Affiliation(s)
- Anju Kumari
- Department of Physics, School of Applied Sciences, REVA University, Bengaluru 560064, India
| | - Shobith M Shanbogh
- Department of Physics, School of Applied Sciences, REVA University, Bengaluru 560064, India
| | - Iranna Udachyan
- Department of Chemical Science, The Radical Research Center and the Schlesinger Family Center for Compact Accelerators, Radiation Sources and Application, Ariel University, Ariel 40700, Israel
| | - Sakthivel Kandaiah
- Department of Chemistry, School of Applied Sciences, REVA University, Bengaluru 560064, India
| | - Amit Roy
- Department of Physics, Indian Institute of Science, Bengaluru 560012, India
| | - Vaibhav Varade
- Department of Condensed Matter Physics, Charles University, Prague 116 36, Czech Republic
| | - Anjaneyulu Ponnam
- Department of Physics, School of Applied Sciences, REVA University, Bengaluru 560064, India
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