A5066327937- Quantum and electron transport phenomena
- 2D Materials and Applications
- Graphene research and applications
- Magnetic properties of thin films
- Advanced Memory and Neural Computing
- MXene and MAX Phase Materials
- Semiconductor materials and devices
- Physics of Superconductivity and Magnetism
- Nanowire Synthesis and Applications
- Perovskite Materials and Applications
- Advancements in Semiconductor Devices and Circuit Design
- Advancements in Battery Materials
- Semiconductor Quantum Structures and Devices
- Graphene and Nanomaterials Applications
- Magnetic Field Sensors Techniques
- Ferroelectric and Negative Capacitance Devices
- Surface and Thin Film Phenomena
- Diamond and Carbon-based Materials Research
- Topological Materials and Phenomena
- Electronic and Structural Properties of Oxides
- Theoretical and Computational Physics
- Chalcogenide Semiconductor Thin Films
- Photonic Crystals and Applications
- Molecular Junctions and Nanostructures
- Transition Metal Oxide Nanomaterials
Sejong University
2015-2024
Sungkyunkwan University
2023
Yonsei University
2020
University of Sargodha
2020
University of Central Punjab
2020
Beijing Graphene Institute
2017-2019
Gwangju University
2019
University of Seoul
2014-2017
Government of the Republic of Korea
2016
Korea Institute of Science and Technology
2006-2010
Transistors Switch onto Spin Using the spin of an electron in addition to, or instead of, charge properties is believed to have many benefits terms speed, power-cost, and integration density over conventional electronic circuits. At heart field spintronics has been a proposed spin-analog transistor, effect transistor. Koo et al. (p. 1515 ) demonstrate injection detection between two ferromagnetic contacts show how magnitude spin-current source drain can be controlled by voltage applied gate....
An emerging electronic material as one of transition metal dichalcogenides (TMDCs), tungsten disulfide (WS2) can be exfoliated an atomically thin layer and compensate for the drawback graphene originating from a gapless band structure. A direct bandgap, which is obtainable in single-layer WS2, attractive characteristic developing optoelectronic devices, well field-effect transistors. However, its relatively low mobility electrical characteristics susceptible to environments remain obstacles...
Abstract Bipolar junction transistors (BJTs), the basic building blocks of integrated circuits, are deployed to control switching applications and logic operations. However, as thickness a conventional BJT device approaches few atoms, its performance decreases substantially. The stacking atomically thin 2D semiconductor materials is advantageous for manufacturing devices owing high carrier density electrons holes. Here, an n–p–n composed heavily doped molybdenum ditelluride (n‐MoTe 2 )...
We report on the frictional force between an SiN tip and graphene/graphite surfaces using lateral microscopy. The cantilever we have used was made of membrane has a low stiffness 0.006 N m(-1). prepared graphene flakes Si wafer covered with silicon oxides. smaller than that oxide larger graphite (multilayer graphene). Force spectroscopy also employed to study van der Waals tip. Judging in graphite-graphene-silicon order, friction is suspected be related interactions. As normal acting surface...
The properties of single-layer graphene are strongly affected by metal adsorbates and clusters on graphene. Here, we study the effect a thin layer chromium (Cr) titanium (Ti) metals chemical vapor deposition (CVD)-grown using Raman spectroscopy transport measurements. spectra measurements show that both Cr Ti affect structure as well electronic CVD-grown shift peak frequencies, intensities widths bands analyzed after films different thickness shifts in G 2D positions indicate doping metals....
The development of low resistance contacts to 2D transition-metal dichalcogenides (TMDs) is still a big challenge for the future generation field effect transistors (FETs) and optoelectronic devices. Here, we report chemical doping technique achieve contact by keeping intrinsic properties few layers WS2. transfer length method has been used investigate on resistance. After doping, (Rc) multilayer (ML) WS2 reduced 0.9 kΩ·μm. significant reduction Rc mainly due high electron density, thus in...
We report a simple and mass-scalable approach for thin MoS2 films via RF sputtering combined with the post-deposition annealing process. have prepared as-sputtered film using target in system. The was subjected to improve crystalline quality at 700 °C sulfur argon environment. analysis confirmed growth of continuous bilayer few-layer film. mobility value ~29 cm(2)/Vs current on/off ratio on order ~10(4) were obtained MoS2. increased up ~173-181 cm(2)/Vs, respectively, our FETs is larger than...
Van der Waals (vdW) heterostructures composed of atomically thin two-dimensional (2D) materials have more potential than conventional metal-oxide semiconductors because their tunable bandgaps, and sensitivities. The remarkable features these amazing vdW are leading to multi-functional logic devices, photodetectors, negative differential resistance (NDR) Esaki diodes. Here, an stacking p-type black arsenic (b-As) n-type tin disulfide (n-SnS
Abstract To avoid the complexity of circuit for in‐memory computing, simultaneous execution multiple logic gates (OR, AND, NOR, and NAND) memory behavior are demonstrated in a single device oxygen plasma‐treated gallium selenide (GaSe) memtransistor. Resistive switching with R ON /R OFF ratio range 10 4 to 6 is obtained depending on channel length (150 1600 nm). Oxygen plasma treatment GaSe film created shallow deep‐level defect states, which exhibit carriers trapping/de‐trapping, that lead...
Emerging technologies such as neuromorphic computing and nonvolatile memories based on floating gate field-effect transistors (FETs) hold promise for addressing a wide range of artificial intelligence tasks. For example, seeks to emulate the human brain's functionality employs device that mimics role synapse in brain. However, achieving high current ON/OFF ratio program erase states memory with metal is necessary. This study demonstrates multi-functional heterostructures transition...
In this article, we report layer-controlled, continuous and large-area molydenum sulfide (MoS2) growth onto a SiO2/Si substrate by RF sputtering combined with sulfurization. A two-step process was employed to synthesize MoS2 films. the first step, an atomically thin MoO3 film deposited magnetron at 300 °C. Subsequently, as-sputtered further subjected post-annealing sulfurization processes 650 °C for 1 hour. It observed that number of layers can be controlled adjusting time. The fabricated...
Molybdenum disulfide (MoS2) has recently emerged as a promising candidate for fabricating ultrathin-film photovoltaic devices. These devices exhibit excellent performance, superior flexibility, and low production cost. Layered MoS2 deposited on p-Si establishes built-in electric field at MoS2/Si interface that helps in photogenerated carrier separation operation. We propose an Al2O3-based passivation the surface to improve performance of bulklike solar cells. Interestingly, it was observed...
Abstract Precise doping-profile engineering in van der Waals heterostructures is a key element to promote optimal device performance various electrical and optical applications with two-dimensional layered materials. Here, we report tungsten diselenide- (WSe 2 ) based pure vertical diodes atomically defined p-, i- n-channel regions. Externally modulated p- n-doped layers are respectively formed on the bottom top facets of WSe single crystals by direct evaporations high low work-function...
Heterostructures comprising two-dimensional (2D) semiconductors fabricated by individual stacking exhibit interesting characteristics owing to their 2D nature and atomically sharp interface. As an emerging material, black phosphorus (BP) nanosheets have drawn much attention because of small band gap semiconductor along with high mobility. Stacking structures composed p-type BP n-type transition metal dichalcogenides can produce interface van der Waals interaction which leads p-n diode...
This paper reports on high photo responsivity (<italic>R</italic><sub>λ</sub> ∼ 1913 AW<sup>−1</sup>) of MoS<sub>2</sub> photodetector by decorating a thin layer ZnO quantum dots MoS<sub>2</sub>.
It is of immense interest to improve the power conversion efficiency graphene/silicon Schottky junction solar cells. The ultrathin graphene has essential properties, such as tunable work function increase barrier height and built-in potential for efficient charge transport in photovoltaic devices. Here, we use plasma-enhanced CVD grow directly on planar n-type silicon fabricate cells compatible industrial-level applications. A key component our accomplishment optimization grown, continuous...
Vertical heterostructures of transition-metal dichalcogenide semiconductors have attracted considerable attention and offer new opportunities in electronics optoelectronics for the development innovative multifunctional devices. Here, we designed a novel compact vertically stacked two-dimensional (2D) n-WS2/p-GeSe/n-WS2 van der Waals (vdW) heterojunction bipolar transistor (2D-HBT)-based chemical sensor. The performance 2D-HBT vdW heterostructure with different base thicknesses is...
We present a van der Waals p-MoTe<sub>2</sub>/n-MoTe<sub>2</sub>homojunction p–n diode with low resistance metal contacts.
Abstract 2D layered germanium selenide (GeSe) with p -type conductivity is incorporated asymmetric contact electrode of chromium/Gold (Cr/Au) and Palladium/Gold (Pd/Au) to design a self-biased, high speed an efficient photodetector. The photoresponse under photovoltaic effect investigated for the wavelengths light (i.e. ~220, ~530 ~850 nm). device exhibited promising figures merit required photodetection, specifically Schottky barrier diode highly sensitive NIR irradiation at zero voltage...
Graphene is an air-friendly material that can be easily p-doped by oxygen; therefore, a stable, defect-free, and efficient graphene n-doping technique should developed for achieving high performance in electronic optoelectronic devices. In this study, we present unique method n-type chemical doping of monolayer grown through vapor deposition. The process thoroughly examined using X-ray photoelectron spectroscopy, Raman ultraviolet spectroscopy. findings demonstrate the use KBr solution...