A5101543221- Ferroelectric and Negative Capacitance Devices
- Semiconductor materials and devices
- Perovskite Materials and Applications
- Advanced Memory and Neural Computing
- Quantum Dots Synthesis And Properties
- Organic Light-Emitting Diodes Research
- ZnO doping and properties
- Ferroelectric and Piezoelectric Materials
- Electronic and Structural Properties of Oxides
- Advanced Photonic Communication Systems
- Optical Network Technologies
- Advanced Sensor and Energy Harvesting Materials
- Conducting polymers and applications
- GaN-based semiconductor devices and materials
- MXene and MAX Phase Materials
- Luminescence and Fluorescent Materials
- TiO2 Photocatalysis and Solar Cells
- Photonic and Optical Devices
- Wood Treatment and Properties
- Fiber-reinforced polymer composites
- Advanced Photocatalysis Techniques
- Semiconductor Lasers and Optical Devices
- Advanced Optical Network Technologies
- Organic Electronics and Photovoltaics
- Natural Fiber Reinforced Composites
Korea University
2021-2025
Georgia Institute of Technology
2025
Samsung (South Korea)
2016-2024
Electronics and Telecommunications Research Institute
2001-2024
Sejong University
2021-2024
Seoul National University
2018-2021
Chungnam National University
2020-2021
Tohoku University
2008-2011
High-performance organic field-effect transistors (OFETs) based on polyelectrolyte gate dielectric and electrospun poly(3-hexylthiophene) (P3HT) nanofibers were fabricated a flexible polymer substrate. The use of UV-crosslinked hydrogel including ionic liquids for the insulating layer enabled fast large-area fabrication transistor arrays. P3HT directly deposited methacrylated During UV irradiation through patterned mask, methacrylate groups formed covalent bonds with layer, which provides...
Stretchable organic light-emitting diodes are ubiquitous in the rapidly developing wearable display technology. However, low efficiency and poor mechanical stability inhibit their commercial applications owing to restrictions generated by strain. Here, we demonstrate exceptional performance of a transparent (molybdenum-trioxide/gold/molybdenum-trioxide) electrode for buckled, twistable, geometrically stretchable under 2-dimensional random area strain with invariant color coordinates. The...
Abstract Ferroelectric materials offer a low‐energy, high‐speed alternative to conventional logic and memory circuitry. Hafnia‐based films have achieved single‐digit nm ferroelectricity, enabling further device miniaturization. However, they can exhibit nonideal behavior, specifically wake‐up fatigue effects, leading unpredictable performance variation over consecutive electronic switching cycles, preventing large‐scale commercialization. The origins are still under debate. Using...
Three new D−π–A-structured organic dyes, coded as SGT-138, SGT-150, and SGT-151, with the expansion of π-conjugation in π-bridge acceptor parts have been developed to adjust HOMO/LUMO levels expand light absorption range dyes. Referring SGT-137 dye, group was extended from 4-hexyl-4H-thieno[3,2-b]indole (TI) 9-hexyl-9H-thieno[2′,3′:4,5]thieno[3,2-b]indole (TII), (E)-3-(4-(benzo[c][1,2,5]thiadiazol-4-yl)phenyl)-2-cyanoacrylic acid (BTCA)...
Ferroelectric Field-Effect Transistors Because of their simple structure and operation scheme based on characteristic spontaneous polarization, ferroelectric field-effect-transistors (FeFETs), which are reviewed by Jinseong Heo, Min Hyuk Park, co-workers in article number 2204904, considered promising for ultrahigh-density information storage with high speed power efficiency. A post-3D-NAND the FeFET is shown.
Despite significant progress in device performance, dye-sensitized solar cells (DSSCs) continue to fall short of their theoretical potential. Moreover, research recent years needs pay more attention improving the fabrication process. To achieve efficiency limit, it is crucial optimize interface between dye and TiO2 nanoparticles entire stack. Our study indicates that optimizing structure or size coadsorbents implementing a monolayer adsorption process can be an effective strategy reduce...
In the solution process using perovskite nanocrystals (PNCs) as emitting materials for light-emitting diodes (LEDs), solvent orthogonality typically plays a crucial role in preserving stable interfacial conditions between carrier transport layers on both sides. Unfortunately, there is lack of clear understanding which to choose and what effects has realizing photo/electroluminescence (PL EL) properties given PNCs. Here, we investigate impact merely changing dispersing solvents PNCs, belong...
In this work, we report a planar Si-based ferroelectric field-effect transistor (FEFET) characterized by high memory window (MW) of 4.79 V, ten-year retention, and pass disturb-free characteristics. This achievement is realized through the use 20-nm-thick laminated Hf <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$_{{0}.{5}}$ </tex-math></inline-formula> Zr0.5O2 (L-HZO) film with Al2O3 (AO)-insertion...
<h2>Summary</h2> Investigating exciton dynamics and device physics in phosphorescent organic light-emitting diodes (Ph-OLEDs) is important for developing highly efficient devices with optimal color purity. Herein, we conduct an in-depth exploration of the recombination zone various radiative transitions within blue Ph-OLEDs using operando electrically pumped spectroscopy. It serves as a versatile tool enabling simultaneous analysis time-resolved electroluminescence photoluminescence. Our...
In this study, a block shear strength test was conducted to compare and analyze the failure mode on glued laminated timber, CLT, Ply-lam which are mainly used for construction of wood as engineering wood. Through this, CLT manufacturing conditions optimum production, such type lamina, plywood, adhesive, layer composition, were investigated. The results follow. test, it showed high in order CLT. particular, is made composite structure larch plywood passed 7.1 N/mm2, Korean industrial...
The purpose of this study is to optimize the bonding method plywood suitable for cross-laminated timber (CLT) with as a core by analyzing flexural performance and failure mode according lamina species, in longitudinal direction, whether or not adhesive applied joint. In case Douglas fir layer, modulus elasticity decreased about 11.5% due bonding, rupture increased application method. optimal conditions were derived butt joint without adhesive, half lap larch 15% 40%, respectively. When using...
Abstract We propose a novel synaptic design of more efficient neuromorphic edge-computing with substantially improved linearity and extremely low variability. Specifically, parallel arrangement ferroelectric tunnel junctions (FTJ) an incremental pulsing scheme provides great improvement in for weight updating by averaging update rates multiple devices. To enable such FTJ building blocks, we have demonstrated the lowest reported variability: σ / μ = 0.036 cycle to 0.032 device among six dies...
Abstract The presence of 2D electron gas (2DEG) at the interface between an amorphous Al 2 O 3 ( a ‐AO) thin film and anatase TiO (TO) is demonstrated. ‐AO TO films are prepared via atomic layer deposition on SrTiO (STO) single crystal substrate. reduction surface during produces oxygen vacancies, which effective donors. systematic analysis physical properties reveals that crystallinity affects conductivity, carrier concentration mobility 2DEG, also critical thickness, minimum thickness for...
The desire to enhance the efficiency of organic light-emitting devices (OLEDs) has driven investigation advanced materials with fascinating properties. In this work, top-emission OLEDs (TEOLEDs) is enhanced by introducing ampicillin microstructures (Amp-MSs) dual phases (α-/β-phase) that induce photoluminescence (PL) and electroluminescence (EL). Moreover, Amp-MSs can adjust charge balance Fermi level (EF ) alignment, thereby decreasing leakage current. decrease in wave-guided modes light...
We report significant reduction of threading dislocations in GaN films grown by hydride vapor phase epitaxy on AlN/sapphire templates employing CrN nanoislands the AlN. High quality with very small twist mosaic as well tilt have been templates, which had but large mosaic. The were formed nitridation a thin Cr film deposited sputtering template, where template was prepared metal organic epitaxy. full width at half maximum values x-ray rocking curves from 114, 209, and 243arcsec for (0002),...
Herein, an unprecedented report is presented on the incorporation of size-dependent gold nanoparticles (AuNPs) with polyvinylpyrrolidone (PVP) capping into a conventional hole transport layer, poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS). The layer blocks ion-diffusion/migration in methylammonium-lead-bromide (MAPbBr
Abstract The 2D electron gas (2DEG) phenomenon that occurs at the amorphous thin film hetero‐oxide interface attracts great attention since it can avoid use of a single‐crystal oxide substrate. In this study, analysis 2DEG amorphous‐Al 2 O 3 ( ‐AO)/ZnO is conducted using ZnO as bottom substrate, where both films are grown by atomic layer deposition. Having used Al(CH ) Al‐precursor for ‐AO growth on previously film, its strong reducing power induces formation interface. As result Hall...
Ternary Solvent Engineering In article number 2300604, Islam, Jesuraj, Ryu and co-workers demonstrate a way to control defects voids by ternary solvent engineering. The power conversion efficiency (PCE) with the increased over 20% uniform perovskite morphology minimal defects. Additionally, engineering could be beneficial from an industrial perspective for achieving stable large-area devices.
This study presents a material selection strategy for the interfacial layer (IL) in ferroelectric (FE) memory stacks. The nucleation-limited switching (NLS) model was applied to analyze kinetics of metal/FE/insulator/metal (MFIM) structure, where Hf0.5Zr0.5O2 (HZO) used as FE. Activation field ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${E}_{a}$ </tex-math></inline-formula> ) and characteristic time...
Ferroelectric HfO2-based films incorporated in nonvolatile memory devices offer a low-energy, high-speed alternative to conventional systems. Oxygen vacancies have been rigorously cited literature be pivotal stabilizing the polar noncentrosymmetric phase responsible for ferroelectricity films. Thus, ability regulate and control oxygen vacancy migration operando such materials would potentially step changing new functionalities, tunable electrical properties, enhanced device lifespan. Herein,...
Abstract A transistor is fabricated with a 2D electron gas (2DEG) channel at the Al 2 O 3 (AO)/SrTiO (STO) interface. The threshold voltage ( V th ) shift of 2DEG in Pt/AO/2DEG/STO stack induced by negative bias stress investigated. Two‐terminal current–voltage and capacitance–voltage characterization through gate source reveals that metallic turns into semiconducting when applied. Transfer curve measurement various conditions on field‐effect performed to evaluate effect stress. becomes...
Transient phenomena of hybrid Raman/erbium-doped fiber amplifier (EDFA) upon optical channel add-drop are investigated. The transient responses surviving channels resulted from the combined dynamics Raman and EDFA. It is shown that suggested method employing fast gain control EDFA only can effectively suppress variation output power. transient-suppressing Raman/EDFA proven to be enough for wavelength-division-multiplexing networks including reconfigurable multiplexer and/or transparent...