A5061354200- Nanowire Synthesis and Applications
- Graphene research and applications
- Silicon Nanostructures and Photoluminescence
- 2D Materials and Applications
- Photonic and Optical Devices
- Advanced Memory and Neural Computing
- Anodic Oxide Films and Nanostructures
- Semiconductor materials and interfaces
- Semiconductor materials and devices
- Carbon and Quantum Dots Applications
- Thin-Film Transistor Technologies
- MXene and MAX Phase Materials
- Neural Networks and Reservoir Computing
- Plasmonic and Surface Plasmon Research
- Neuroscience and Neural Engineering
- Machine Learning in Materials Science
- ZnO doping and properties
- Ga2O3 and related materials
- Photoreceptor and optogenetics research
- Advancements in Semiconductor Devices and Circuit Design
- Perovskite Materials and Applications
- Graphene and Nanomaterials Applications
- Mechanical and Optical Resonators
- Advanced Thermoelectric Materials and Devices
- Orbital Angular Momentum in Optics
Jeju National University
2021-2025
Government of the Republic of Korea
2021
Johns Hopkins University
2019-2020
Korea University
2017-2020
Kyung Hee University
2010-2016
Samsung (South Korea)
2016
Korea Research Institute of Standards and Science
2011-2014
Korea University of Science and Technology
2011-2012
Triboelectric charging involves frictional contact of two different materials, and their electrification usually relies on polarity difference in the triboelectric series. This limits choices materials for pairs, hindering research development energy harvest devices utilizing effect. A progressive approach to resolve this issue modification chemical structures effectively engineering properties. Here, we describe a facile method change property polymeric surface via atomic-level...
Au/Ag bilayered metal mesh with arrays of nanoholes were devised as a catalyst for metal-assisted chemical etching silicon. The present allows us not only to overcome drawbacks involved in conventional Ag-based processes, but also fabricate extended silicon nanowires (SiNWs) controlled dimension and density. We demonstrate that SiNWs different morphologies axial orientations can be prepared from wafers given orientation by controlling the conditions. explored phenomenological model explains...
We report substantially enhanced photoluminescence (PL) from hybrid structures of graphene/ZnO films at a band gap energy ZnO (∼3.3 eV/376 nm). Despite the well-known constant optical conductivity graphene in visible-frequency regime, its abnormally strong absorption violet-frequency region has recently been reported. In this Letter, we demonstrate that resonant excitation plasmon is responsible for such and eventually contributes to photoemission when corrugation surface modulates photons...
Electronic pacemakers can treat electrical conduction disorders in hearts; however, they are invasive, bulky, and linked to increased incidence of infection at the tissue-device interface. Thus, researchers have looked other more biocompatible methods for cardiac pacing or resynchronization, such as femtosecond infrared light pulsing, optogenetics, polymer-based patches integrated with metal electrodes. Here we develop a nongenetic approach optical modulation cells tissues. We demonstrate...
Abstract Optical vector vortex beams provide additional degrees of freedom for spatially distinguishable channels in data transmission. Although several coherent light sources carrying a topological singularity have been reported, it remains challenging to develop general strategy designing ultra-small, high-quality photonic nanocavities that generate and support optical modes. Here we demonstrate wavelength-scale, low-threshold, anti-vortex nanolasers C 5 symmetric cavity formed by...
Abstract We develop a nanoheater utilizing single Si nanowire with porous segment that produces localized heat. The 19-fold higher resistivity of the compared to solid in facilitates substantial confinement heat by Joule heating. profiles are examined using scanning thermal microscopy, direct imaging technique. recorded along longitudinal and cross-sectional axes reveal is concentrated sub-micrometer region segment, whereas it uniformly distributed whole axis homogeneous nanowire. Moreover,...
A generic process for the preparation of curved silicon nanowires (SiNWs) with ribbon-like cross sections was developed. The present synthetic approach is based on chemical etching (100)-oriented wafers in mixture solutions HF and H(2)O(2) by using patterned thin gold films as catalyst provides a unique opportunity fabrication extended arrays zigzag SiNWs, ultrathin straight [111] SiNWs controlled turning angles. On basis our experiments performed under various conditions, factors governing...
Porous silicon (PSi) is recognized as an attractive building block for photonic devices because of its novel properties including high ratio surface to volume and light absorption. We first report near-ultraviolet (UV)-sensitive graphene/PSi photodetectors (PDs) fabricated by utilizing graphene PSi a carrier collector photoexcitation layer, respectively. Thanks absorption enlarged energy-band gap PSi, the responsivity (Ri) quantum efficiency (QE) PDs are markedly enhanced in near-UV range....
Quantum confinement in transition metal dichalcogenides (TMDCs) enables the realization of deterministic single-photon emitters. The position and polarization control single photons have been achieved via local strain engineering using nanostructures. However, most existing TMDC-based emitters are operated by optical pumping, while emission sites electrically pumped uncontrolled. Here, we demonstrate driven located at positions where strains induced atomic force microscope indentation on a...
Abstract The incorporation of metal-organic frameworks into advanced devices remains a desirable goal, but progress is hindered by difficulties in preparing large crystalline framework films with suitable electronic performance. We demonstrate the direct growth large-area, high quality, and phase pure single crystals through chemical vapor deposition dimolybdenum paddlewheel precursor, Mo 2 (INA) 4 . These exceptionally uniform, quality cover areas up to 8600 µm can be grown down thicknesses...
Graphene/Si quantum dot (QD) heterojunction diodes are reported for the first time. The photoresponse, very sensitive to variations in size of QDs as well doping concentration graphene and consistent with quantum-confinement effect, is remarkably enhanced near-ultraviolet range compared commercially available bulk-Si photodetectors. photoresponse proves be dominated by carriertunneling mechanism.
Wafer-scale graphene/Si-nanowire (Si-NW) array heterostructures for molecular sensing have been fabricated by vertically contacting single-layer graphene with high-density Si NWs. Graphene is grown in large scale chemical vapour deposition and NWs are aligned metal-assisted etching of wafer. plays a key role preventing tips vertical from being bundled, thereby making stand on wafer separately each other under graphene, critical structural feature the uniform Schottky-type junction between...
Abstract Förster resonance energy transfer (FRET), referred to as the of photon absorbed in donor acceptor, has received much attention an important physical phenomenon for its potential applications optoelectronic devices well understanding some biological systems. If one-atom-thick graphene is used or it can minimize separation between and thereby maximizing FRET efficiency ( E ). Here, we report first fabrication a system composed silica nanoparticles (SNPs) quantum dots (GQDs) donors...
Nonvolatile flash-memory capacitors containing graphene quantum dots (GQDs) of 6, 12, and 27 nm average sizes (d) between SiO2 layers for use as charge traps have been prepared by sequential processes: ion-beam sputtering deposition (IBSD) 10 on a p-type wafer, spin-coating GQDs the layer, IBSD 20 GQD layer. The presence almost single array at distance ∼13 from SiO2/Si wafer interface is confirmed transmission electron microscopy photoluminescence. memory window estimated capacitance-voltage...
We first report graphene-assisted chemical etching (GaCE) of silicon by using patterned graphene as an catalyst. Chemical-vapor-deposition-grown transferred on a substrate is to mesh with nanohole arrays oxygen plasma anodic- aluminum-oxide mask. The prepared mesh/silicon immersed in mixture solution hydrofluoric acid and hydro peroxide various molecular fractions at optimized temperatures. underneath then selectively etched form aligned nanopillar arrays. morphology the nanostructured can...
A simple, cost-effective, and highly reliable method for constructing an air-bridged electrical contact on large arrays of vertically aligned nanowires was developed. The present may open up new opportunities developing advanced nanowire-based devices energy harvest storage, power generation, sensing applications.
A simple top–down approach for the continuous mass preparation of single crystalline silicon nanowires (SiNWs) with controlled lengths was developed. The is based on periodic pulsing anodic bias during gold-assisted chemical etching a substrate and subsequent ultrasonic treatment resulting porosity-patterned SiNWs selective breakage at porous segments, allows us to overcome some drawbacks in conventional bottom–up methods SiNW growth.
Abstract Single-Si-nanowire (NW)-based DNA sensors have been recently developed, but their sensitivity is very limited because of high noise signals, originating from small source-drain current the single Si NW. Here, we demonstrate that chemical-vapor-deposition-grown large-scale graphene/surface-modified vertical-Si-NW-arrays junctions can be utilized as diode-type biosensors for highly-sensitive and -selective detection specific oligonucleotides. For this, a twenty-seven-base-long...
The development of memory devices with functions that simultaneously process and store data is required for efficient computation. To achieve this, artificial synaptic have been proposed because they can construct hybrid networks biological neurons perform neuromorphic However, irreversible aging these electrical causes unavoidable performance degradation. Although several photonic approaches to controlling currents suggested, suppression current levels switching analog conductance in a...
We report the enhancement of light absorption in Si nanowire photovoltaic devices with one-dimensional dielectric or metallic gratings that are fabricated by a damage-free, precisely aligning, polymer-assisted transfer method. Incorporation Si3N4 grating effectively enhances photocurrents for transverse-electric polarized light. The wavelength at which maximum photocurrent is generated readily tuned adjusting pitch. Moreover, electrical properties preserved before and after transferring onto...