A5050319646- ZnO doping and properties
- Quantum Dots Synthesis And Properties
- Supercapacitor Materials and Fabrication
- Advanced Sensor and Energy Harvesting Materials
- Chalcogenide Semiconductor Thin Films
- Conducting polymers and applications
- Nanowire Synthesis and Applications
- Advancements in Battery Materials
- Gas Sensing Nanomaterials and Sensors
- Ga2O3 and related materials
- Electrospun Nanofibers in Biomedical Applications
- Semiconductor materials and devices
- Copper-based nanomaterials and applications
- Advanced Memory and Neural Computing
- Graphene research and applications
- Thin-Film Transistor Technologies
- Carbon Nanotubes in Composites
- Electronic and Structural Properties of Oxides
- Electrochemical sensors and biosensors
- Nanomaterials and Printing Technologies
- Advanced battery technologies research
- Electrocatalysts for Energy Conversion
- MXene and MAX Phase Materials
- Liquid Crystal Research Advancements
- Laser-Ablation Synthesis of Nanoparticles
Korea Institute of Machinery and Materials
2008-2024
Korea Institute of Geoscience and Mineral Resources
2014-2023
Daejeon University
2021
Government of the Republic of Korea
2021
Korea University of Science and Technology
2018
Kookmin University
2017
University of Pennsylvania
2012-2016
Yonsei University
2006-2011
Korea Institute of Science and Technology
2008
Seoul National University
2001-2008
We report bandlike transport in solution-deposited, CdSe QD thin-films with room temperature field-effect mobilities for electrons of 27 cm(2)/(V s). A concomitant shift and broadening the solid optical absorption compared to that dispersed samples is consistent electron delocalization measured mobilities. Annealing indium contacts allows thermal diffusion doping thin-films, shifting Fermi energy, filling traps, providing access bands. Temperature-dependent measurements show 220 K on a...
Synthetic methods produce libraries of colloidal nanocrystals with tunable physical properties by tailoring the nanocrystal size, shape, and composition. Here, we exploit diversity design materials, interfaces, processes to construct all-nanocrystal electronic devices using solution-based processes. Metallic silver semiconducting cadmium selenide are deposited form high-conductivity high-mobility thin-film electrodes channel layers field-effect transistors. Insulating aluminum oxide...
We investigate the effects of stoichiometric imbalance on electronic properties lead chalcogenide nanocrystal films by introducing excess (Pb) or selenium (Se) through thermal evaporation. Hall-effect and capacitance-voltage measurements show that carrier type, concentration, Fermi level in solids may be precisely controlled their stoichiometry. By manipulating only stoichiometry solids, we engineer characteristics optoelectronic devices. Lead field-effect transistors (FETs) are fabricated...
We report a simple, solution-based, postsynthetic colloidal, atomic layer deposition (PS-cALD) process to engineer stepwise the surface stoichiometry and therefore electronic properties of lead chalcogenide nanocrystal (NC) thin films integrated in devices. found that unlike chalcogen-enriched NC surfaces are structurally, optically, electronically unstable, chloride treatment creates well-passivated shell stabilizes NCs. Using PS-cALD we demonstrate high electron field-effect mobilities...
Vertically aligned ZnO nanowires were grown on c-plane sapphire substrate by metal organic chemical vapor deposition technique. The single crystalline and structurally uniform did not exhibit any noticeable defects. Pt/ZnO nanowire Schottky diodes fabricated using e-beam lithography then characterized measuring temperature-dependent I−V characteristics. diode exhibited a low barrier height of 0.42 V ideality factor 1.6 at room temperature. Temperature-dependent hydrogen-sensing measurements...
We study charge injection and transport in PbSe nanocrystal thin films. By engineering the contact metallurgy ligand exchange chemistry surface passivation, we demonstrate partial Fermi-level pinning at metal–nanocrystal interface an insulator-to-metal transition with increased coupling doping, allowing us to design high conductivity mobility construct complementary circuits from n-type p-type transistors realized a single material by selecting metallurgy.
In this report, ZnO single nanowire (NW)-based devices were fabricated on the same by e-beam lithography so that both sides had Ohmic contact and one side Schottky contact. Information about mechanism for low-power UV detection these was unambiguously provided I-V measurements. Adsorption desorption of oxygen molecules at NW surface are responsible device with contacts sides. Barrier height modulations interface states side.
Transparency of the glass substrate plays an important role in performance many optical and electronic devices. Herein, authors have demonstrated a simple method to create high wide–range anti-reflection layer on surface by "carving" it with hot alkali solution (95 °C). Morphology, composition, properties were controlled changing both original composition substrates etching time. Enhanced transparency (up 97.7%) was achieved wide wavelength range. Superhydrophilic antifogging also...
Abstract A large amount of silicon debris particles are generated during the slicing ingots into thin wafers for fabrication integrated-circuit chips and solar cells. This results in a significant loss valuable materials at about 40% mass ingots. In addition, hazardous sludge waste is produced containing largely carbide, which common cutting material on saw. Efforts recovery from recycling have been directed towards converting or carbide other chemicals. Here, we report an aerosol-assisted...
Titanium oxide passivation layer was employed and optimized to stabilize the performance of bottom gate amorphous indium–gallium–zinc (a-IGZO) thin-film transistors (TFTs). A molybdenum/titanium (Mo/Ti) source–drain electrode deposited on an a-IGZO layer, formed by oxidizing Ti using oxygen plasma after etching Mo layer. By increasing treatment time, subthreshold slope leakage current TFTs were improved 0.3 pA, respectively, degradation TFT not observed, even thermal at for 1 h.
Colloidal semiconductor nanocrystal (NC) thin films have been integrated in light-emitting diodes, solar cells, field-effect transistors (FETs), and flexible, electronic circuits. However, NC devices are typically fabricated operated an inert environment since the reactive surface high surface-to-volume ratio of materials render them sensitive to oxygen, water, many solvents. This sensitivity has limited device scaling large-scale integration achievable by conventional fabrication...
Abstract Crumpled graphene (CGR) is considered a promising supercapacitor material to achieve high power and energy density because it could overcome the disadvantages of 2 D GR sheets such as aggregation during electrode fabrication process, reduction available surface area, limitation electron ion transport. Even though CGR shows good results, carbon materials are limited in terms their capacitance performance. Here, we report highly enhanced by fabricating 3 composite containing CGR,...
Next-generation devices and systems require the development integration of advanced materials, realization which inevitably requires two separate processes: property engineering patterning. Here, we report a one-step, ink-lithography technique to pattern engineer properties thin films colloidal nanocrystals that exploits their chemically addressable surface. Colloidal are deposited by solution-based methods form local chemical treatment is applied using an ink-printing simultaneously modify...
The multiple-step synthesis, harmful organic solvents, and hazardous binders are the major obstacles for supercapacitor (SC) designers. A conventional synthesis of nanocomposite is normally involves complex steps time-consuming. To reduce these multiple process time, we report carbon nitride-doped gadolinium sulfide (CN/Gd2S3) obtained via a one-step in situ thermal reduction method. In our study, introduce poly(3,4-ethylenedioxythiophenes): polystyrene sulfonate (PEDOT–PSS) to act as dual...
Electro-optic performance of a liquid-crystal (LC) system is enhanced by TiO(2) nanoparticle dispersed in nematic liquid crystal (NLC). The 2.5 V threshold voltage LC for device operation lowered to 0.5 through mixing up 2 wt.%. To characterize the shape and size distribution nanoparticles, high-resolution transmission electron microscopy employed. Transmittance spectra structure nondispersed showed that transparency similar pure LC.
We report the controlled and selective doping of colloidal PbSe nanowire arrays to define pn junctions for electronic optoelectronic applications. The nanowires are remotely doped through their surface, p-type by exposure oxygen n-type introducing a stoichiometric imbalance in favor excess lead. By employing patternable poly(methyl)methacrylate blocking layer, we along length. demonstrate integrated complementary metal-oxide semiconductor inverters axially that have gains 15 near full signal...