A5083829802- Copper Interconnects and Reliability
- Electronic Packaging and Soldering Technologies
- Semiconductor materials and devices
- 3D IC and TSV technologies
- Advanced Sensor and Energy Harvesting Materials
- Metal and Thin Film Mechanics
- Phase-change materials and chalcogenides
- Thin-Film Transistor Technologies
- Semiconductor materials and interfaces
- Chalcogenide Semiconductor Thin Films
- Conducting polymers and applications
- ZnO doping and properties
- Nanomaterials and Printing Technologies
- Electrocatalysts for Energy Conversion
- CO2 Reduction Techniques and Catalysts
- Advancements in Battery Materials
- Integrated Circuits and Semiconductor Failure Analysis
- Advanced Surface Polishing Techniques
- Advanced Photocatalysis Techniques
- Graphene research and applications
- Electrodeposition and Electroless Coatings
- Diamond and Carbon-based Materials Research
- Advanced Welding Techniques Analysis
- Nonlinear Optical Materials Studies
- Catalytic Processes in Materials Science
Seoul National University
2015-2024
Ministry of Science and ICT
2024
Advanced Institute of Convergence Technology
2021-2022
University of Seoul
2014-2021
Seoul Institute
2021
Fox Corporation (United States)
2016-2018
Xerox (France)
2016-2018
Teledyne Technologies (United States)
2017-2018
Technical University of Denmark
2017-2018
University of Michigan
2017-2018
We report annealing-free compact TiO<sub>x</sub> layer by atomic deposition for high efficiency flexible perovskite solar cells, and maintained 95% of the initial PCE after 1000 bending cycles with 10 mm radius.
Organogel-based stretchable electronic conductors exhibit electrical conduction even under a large stretching deformation of 300% without electrochemical reactions at DC voltages. The resistance change with is almost strain-insensitive up to 50% strain and it remains each 1000 fatigue cycle. polymeric conductive paths ofPSS are well preserved during the mechanical deformation.
Abstract For steady electroconversion to value-added chemical products with high efficiency, electrocatalyst reconstruction during electrochemical reactions is a critical issue in catalyst design strategies. Here, we report reconstruction-immunized system which Cu nanoparticles are protected by quasi-graphitic C shell. This shell epitaxially grew on bonding via gas–solid reaction governed the CO (g) - 2 (s) equilibrium. The shell-coated was stable reduction and provided platform for rational...
Artificial auxetic sweat ducts enable electronic skin sensors to perform reliable and noninvasive health monitoring over a week.
The enhancement of the electrical conductivity by doping is important in hematite (α-Fe(2)O(3)) photoanodes for efficient solar water oxidation. However, spite many successful demonstrations using extrinsic dopants, such as Sn, Ti, and Si, achieved photocurrent still lower than practical requirement. There lack our understanding how intrinsic oxygen defects can change interact with dopants. In this study, we systematically investigate interplay vacancies Sn dopants context photoanodic...
The evolution of copper-based interconnects requires the realization an ultrathin diffusion barrier layer between Cu interconnect and insulating layers. present work reports use atomically thin graphene as a to metallization. performance is investigated by varying grain size thickness layer; single-layer average 2 ± 1 μm (denoted small-grain SLG), 10 large-grain multi-layer (MLG) 5-10 nm. thermal stability these barriers after annealing Cu/small-grain SLG/Si, Cu/large-grain Cu/MLG/Si stacks...
Low-temperature-processed perovskite solar cells (PSCs), especially those fabricated on flexible substrates, exhibit device performance that is worse than of high-temperature-processed PSCs. One the main reasons for inferior low-temperature-processed PSCs loss photogenerated electrons in electron collection layer (ECL) or related interfaces, i.e., indium tin oxide/ECL and ECL/perovskite. Here, we report tailoring energy level transporting ability oxide ECLs using Zn2SnO4 nanoparticles...
Organic neuromorphic computing/sensing platforms are a promising concept for local monitoring and processing of biological signals in real time. Neuromorphic devices sensors with low conductance power consumption high low-impedance sensing desired. However, it has been struggle to find materials fabrication methods that satisfy both these properties simultaneously single substrate. Here, nanofiber channels self-formed ion-blocking layer fabricated create organic electrochemical transistors...
The effect of local atomic arrangement CuZn alloys was demonstrated on enhanced ethanol selectivity from CO 2 RR and supported by density functional theory (DFT) calculations.
Atomic migration under an electric field, electromigration, in molten and crystalline Ge2Sb2Te5 was studied using a pulsed dc stress to isolated line structure. Under single pulse (∼10−3 s), melted by Joule heating, electrostatic force-induced drift of Ge Sb toward the cathode Te anode observed. Effective charge numbers were calculated be 0.28, 0.38, −0.29 for Ge, Sb, Te, respectively. Electromigration state applying 10 MHz dc; constituent elements migrated cathode, which suggests hole...
Deformation behavior of the Ag nanowire flexible transparent electrode under bending strain is studied and results in a novel approach for highly reliable network with mechanically welded junctions. Bending fatigue tests up to 500 000 cycles are used evaluate situ resistance change while imposing fixed, uniform strain. In initial stages cycles, thermally annealed networks show reduction fractional followed by transient steady‐state increase at later cycling. SEM analysis reveals that caused...
Hematite (α-Fe2O3) has been attracting attention for photoelectrochemical water oxidation due to its visible light photon absorption capacity and high chemical stability, but the short-diffusion length of holes large overpotential are still challenging overcome. Here, in an effort address these challenges, we develop a hierarchically nanostructured photoanode composed iron-oxides; Ti-doped hematite nanorods decorated with undoped underlayer β-FeOOH nano-branches. The nanorod array is...
Abstract As the demand for soft and flexible devices steadily increases, ionic applications demonstrated with gel materials have come under spotlight. Here, stretchable wearable diodes (SIDs) made from polyelectrolyte hydrogels are introduced. Polyelectrolyte mechanically modified using methacrylated polysaccharides while preserving ion‐permselectivity of poly(sulfopropyl acrylate) potassium salt (PSPA) poly([acrylamidopropyl]trimethylammonium chloride) (PDMAPAA‐Q), forming copolymers. Then,...
As the technology of flexible electronics has remarkably advanced, long-term reliability devices attracted much attention, as it is an important factor for such in reaching real commercial viability. To guarantee bending fatigue lifetime, exact evaluation strain and change electrical resistance required. In this study, we investigated strains Cu thin films on polyimide substrates with different thicknesses using monolayer bilayer models monitored metal electrode during a test. For electrode,...
As biological signals are mainly based on ion transport, the differences in signal carriers have become a major issue for intimate communication between electrical devices and areas. In this respect, an ionic device which can directly interpret from systems needs to be designed. Particularly, it is also required amplify effective processing, since amount of ions acquired very small. Here, we report amplification as well sensing through modified design polyelectrolyte hydrogel-based diodes....
Electrocatalysts for CO2 electroreduction require not only high-performance active materials to control the series reaction but also conductive and durable supports ensure long-term stability under harsh operating conditions. Instead of conventional heterogeneous catalysts made by attaching metal on supports, we manufactured a self-formed tandem catalyst designed cascade C2H4. Using oxygen partial pressure-controlled calcination, electrospun copper acetate/polyacrylonitrile nanofibers were...