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Volatile and Nonvolatile Resistive Switching in Lateral 2D Molybdenum Disulfide-Based Memristive Devices
Authors:
Sofía Cruces,
Mohit D. Ganeriwala,
Jimin Lee,
Ke Ran,
Janghyun Jo,
Lukas Völkel,
Dennis Braun,
Bárbara Canto,
Enrique G. Marín,
Holger Kalisch,
Michael Heuken,
Andrei Vescan,
Rafal Dunin-Borkowski,
Joachim Mayer,
Andrés Godoy,
Alwin Daus,
Max C. Lemme
Abstract:
Developing electronic devices capable of emulating biological functions is essential for advancing brain-inspired computation paradigms such as neuromorphic computing. In recent years, two-dimensional materials have emerged as promising candidates for neuromorphic electronic devices. This work addresses the coexistence of volatile and nonvolatile resistive switching in lateral memristors based on…
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Developing electronic devices capable of emulating biological functions is essential for advancing brain-inspired computation paradigms such as neuromorphic computing. In recent years, two-dimensional materials have emerged as promising candidates for neuromorphic electronic devices. This work addresses the coexistence of volatile and nonvolatile resistive switching in lateral memristors based on molybdenum disulfide with silver as the active electrode. The fabricated devices exhibited switching voltages of ~0.16 V and ~0.52 V for volatile and nonvolatile operation, respectively, under direct-current measurements. They also displayed the essential synaptic functions of paired-pulse facilitation and short- and long-term plasticity under pulse stimulation. The operation mechanism was investigated by in-situ transmission electron microscopy, which showed lateral migration of silver ions along the molybdenum disulfide between electrodes. Based on the experimental data, a macroscopic semi-classical electron transport model was used to reproduce the current-voltage characteristics and support the proposed underlying switching mechanisms.
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Submitted 3 April, 2025;
originally announced April 2025.
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Plasma-enhanced atomic layer deposition of Al$_2$O$_3$ on graphene using monolayer hBN as interfacial layer
Authors:
Barbara Canto,
Martin Otto,
Michael J. Powell,
Vitaliy Babenko,
Aileen O Mahony,
Harm Knoops,
Ravi S. Sundaram,
Stephan Hofmann,
Max C. Lemme,
Daniel Neumaier
Abstract:
The deposition of dielectric materials on graphene is one of the bottlenecks for unlocking the potential of graphene in electronic applications. In this paper we demonstrate the plasma enhanced atomic layer deposition of 10 nm thin high quality Al$_2$O$_3$ on graphene using a monolayer of hBN as protection layer. Raman spectroscopy was performed to analyze possible structural changes of the graphe…
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The deposition of dielectric materials on graphene is one of the bottlenecks for unlocking the potential of graphene in electronic applications. In this paper we demonstrate the plasma enhanced atomic layer deposition of 10 nm thin high quality Al$_2$O$_3$ on graphene using a monolayer of hBN as protection layer. Raman spectroscopy was performed to analyze possible structural changes of the graphene lattice caused by the plasma deposition. The results show that a monolayer of hBN in combination with an optimized deposition process can effectively protect graphene from damage, while significant damage was observed without an hBN layer. Electrical characterization of double gated graphene field effect devices confirms that the graphene did not degrade during the plasma deposition of Al$_2$O$_3$. The leakage current densities were consistently below 1 nA/mm for electric fields across the insulators of up to 8 MV/cm, with irreversible breakdown happening above. Such breakdown electric fields are typical for Al$_2$O$_3$ and can be seen as an indicator for high quality dielectric films.
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Submitted 24 August, 2022;
originally announced August 2022.
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Oxidising and carburising catalyst conditioning for the controlled growth and transfer of large crystal monolayer hexagonal boron nitride
Authors:
Vitaliy Babenko,
Ye Fan,
Vlad-Petru Veigang-Radulescu,
Barry Brennan,
Andrew J. Pollard,
Oliver Burton,
Jack A. Alexander-Webber,
Robert S. Weatherup,
Barbara Canto,
Martin Otto,
Daniel Neumaier,
Stephan Hofmann
Abstract:
Hexagonal boron nitride (h-BN) is well-established as a requisite support, encapsulant and barrier for 2D material technologies, but also recently as an active material for applications ranging from hyperbolic metasurfaces to room temperature single-photon sources. Cost-effective, scalable and high quality growth techniques for h-BN layers are critically required. We utilise widely-available iron…
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Hexagonal boron nitride (h-BN) is well-established as a requisite support, encapsulant and barrier for 2D material technologies, but also recently as an active material for applications ranging from hyperbolic metasurfaces to room temperature single-photon sources. Cost-effective, scalable and high quality growth techniques for h-BN layers are critically required. We utilise widely-available iron foils for the catalytic chemical vapour deposition (CVD) of h BN and report on the significant role of bulk dissolved species in h-BN CVD, and specifically, the balance between dissolved oxygen and carbon. A simple pre-growth conditioning step of the iron foils enables us to tailor an error-tolerant scalable CVD process to give exceptionally large h-BN monolayer domains. We also develop a facile method for the improved transfer of as-grown h-BN away from the iron surface by means of the controlled humidity oxidation and subsequent rapid etching of a thin interfacial iron oxide; thus, avoiding the impurities from the bulk of the foil. We demonstrate wafer-scale (2 inch) production and utilise this h-BN as a protective layer for graphene towards integrated (opto) electronic device fabrication.
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Submitted 26 November, 2020;
originally announced November 2020.
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Analogue two-dimensional semiconductor electronics
Authors:
Dmitry K. Polyushkin,
Stefan Wachter,
Lukas Mennel,
Maksym Paliy,
Giuseppe Iannaccone,
Gianluca Fiori,
Daniel Neumaier,
Barbara Canto,
Thomas Mueller
Abstract:
While digital electronics has become entirely ubiquitous in today's world and appears in the limelight, analogue electronics is still playing a crucial role in many devices and applications. Current analogue circuits are mostly manufactured using silicon as active material, but the ever present demand for improved performance, new devices and flexible integration has - similar to their digital cou…
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While digital electronics has become entirely ubiquitous in today's world and appears in the limelight, analogue electronics is still playing a crucial role in many devices and applications. Current analogue circuits are mostly manufactured using silicon as active material, but the ever present demand for improved performance, new devices and flexible integration has - similar to their digital counterparts - pushed for research into alternative materials. In recent years two-dimensional materials have received considerable research interest, fitting their promising properties for future electronics. In this work we demonstrate an operational amplifier - a basic building block of analogue electronics - using a two-dimensional semiconductor, namely molybdenum disulfide, as active material. Our device is capable of stable operation with good performance, and we demonstrate its use in feedback circuits such as inverting amplifiers, integrators, log amplifiers, and transimpedance amplifiers.
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Submitted 31 August, 2019;
originally announced September 2019.
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Non-local electrical detection of spin-polarized surface currents in the 3D topological insulator BiSbTeSe$_{2}$
Authors:
Shaham Jafarpisheh,
Frank Volmer,
Zhiwei Wang,
Bárbara Canto,
Yoichi Ando,
Christoph Stampfer,
Bernd Beschoten
Abstract:
The spin-polarized surface states in topological insulators offer unique transport characteristics that make them distinguishable from trivial conductors. Here, we detect the impact of these surface states in the topological insulator BiSbTeSe$_{2}$ by electrical means using a non-local transport configuration with ferromagnetic Co/Al$_2$O$_3$ electrodes. We show that the non-local measurement all…
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The spin-polarized surface states in topological insulators offer unique transport characteristics that make them distinguishable from trivial conductors. Here, we detect the impact of these surface states in the topological insulator BiSbTeSe$_{2}$ by electrical means using a non-local transport configuration with ferromagnetic Co/Al$_2$O$_3$ electrodes. We show that the non-local measurement allows to probe the surface currents flowing along the whole surface, i.e.~from the top along the side to the bottom surface and back to the top surface along the opposite side. Increasing the temperature increases the interaction between bulk and surface states, which shortens this non-local current path along the surface and hence leads to a complete disappearance of the non-local signal at around 20K. Interestingly, we observe that the ratio between spin signal to background signal is much larger in the non-local geometry compared to the local one. Given that the observed ratio in the non-local geometry aligns well with expectations for spin-polarized surface states, our findings suggest that an as-yet unresolved mechanism diminishes the spin signal in the local geometry.
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Submitted 6 October, 2025; v1 submitted 24 July, 2019;
originally announced July 2019.