A5103202896- Semiconductor Quantum Structures and Devices
- Advanced Semiconductor Detectors and Materials
- Nanowire Synthesis and Applications
- Quantum Dots Synthesis And Properties
- Semiconductor Lasers and Optical Devices
- Photonic and Optical Devices
- Semiconductor materials and devices
- Chalcogenide Semiconductor Thin Films
- Advancements in Semiconductor Devices and Circuit Design
- solar cell performance optimization
- Semiconductor materials and interfaces
- GaN-based semiconductor devices and materials
- Thin-Film Transistor Technologies
- ZnO doping and properties
- Gas Sensing Nanomaterials and Sensors
- Photonic Crystals and Applications
- Quantum and electron transport phenomena
- Silicon Nanostructures and Photoluminescence
- Copper-based nanomaterials and applications
- Transition Metal Oxide Nanomaterials
- Advanced Thermoelectric Materials and Devices
- Advanced Optical Sensing Technologies
- Solar-Powered Water Purification Methods
- 3D IC and TSV technologies
- Electronic and Structural Properties of Oxides
Korea Institute of Science and Technology
2016-2025
Gyeongsang National University Hospital
2022
Gyeongsang National University
2022
Seoul National University
2017-2022
Korea University
2005-2020
Korea University of Science and Technology
2017-2020
Korean Association Of Science and Technology Studies
2002-2018
Korea Advanced Nano Fab Center
2017
Kookmin University
2017
Ulsan National Institute of Science and Technology
2017
We observed a significant enhancement in light output from GaN-based light-emitting diodes (LEDs) which two-dimensional photonic crystal (PC) patterns were integrated. Two-dimensional square-lattice air-hole array with period that varied 300 to 700 nm generated by laser holography. Unlike the commonly utilized electron-beam lithographic technique, holographic method can make over large area high throughput. The resultant PC-LED devices pattern of ∼500nm had more than double power, as...
Abstract Multispectral infrared imaging can acquire spectral information that is not attainable from single band photodetectors. While emerging nanomaterials such as colloidal quantum dots and 2D materials are heavily studied to realize dual‐band photodetectors by stacking them vertically, no device has yet demonstrated high detectivity with response speeds. In this work, bias‐tunable, two‐terminal cover short‐wavelength mid‐wavelength at 300 K. A metamorphic barrier developed connect short...
Herein, a self‐powered electronic nose strategy with highly selective gas detection is described. The two‐dimensional microarray based on the triboelectrification between ZnO nanowires and dielectric layers, heterogeneous catalytic reaction occurring NiO nanoparticles. These noses show ability to distinguish four volatile organic compound (VOC) gases (methanol, ethanol, acetone, toluene) limit of 0.1% at room temperature using no external power source.
Abstract Si-based integrated circuits have been intensively developed over the past several decades through ultimate device scaling. However, Si technology has reached physical limitations of These fuelled search for alternative active materials (for transistors) and introduction optical interconnects (called “Si photonics”). A series attempts to circumvent limits are based on use III-V compound semiconductor due their superior benefits, such as high electron mobility direct bandgap. To...
Abstract One-dimensional crystal growth enables the epitaxial integration of III-V compound semiconductors onto a silicon (Si) substrate despite significant lattice mismatch. Here, we report short-wavelength infrared (SWIR, 1.4–3 μm) photodetector that employs InAs nanowires (NWs) grown on Si. The wafer-scale NWs form Si without metal catalyst or pattern assistance; thus, is free metal-atom-induced contaminations and also cost-effective. NW arrays with an average height 50 μm provide...
Numerous wireless optogenetic systems have been reported for practical tether-free optogenetics in freely moving animals. However, most devices rely on battery-powered or coil-powered requiring periodic battery replacement bulky, high-cost charging equipment with delicate antenna design. This leads to spatiotemporal constraints, such as limited experimental duration due life animals' restricted movement within specific areas maintain power transmission. In this study, we present a wireless,...
One-dimensional crystal growth allows the epitaxial integration of compound semiconductors on silicon (Si), as large lattice-mismatch strain arising from heterointerfaces can be laterally relieved. Here, we report direct heteroepitaxial a mixed anion ternary InAsyP1–y nanowire array across an entire 2 in. Si wafer with unprecedented spatial, structural, and special uniformity dramatic improvements in aspect ratio (>100) area density (>5 × 108/cm2). Heterojunction solar cells consisting...
Lightweight, flexible solar cells from III–V semiconductors offer new application opportunities for devices that require a power supply, such as cars, drones, satellites, or wearable devices, due to their outstanding efficiency and power-to-weight ratio (specific power). However, the specific stability of photovoltaic (PV) need be enhanced use in applications because current PV are vulnerable moisture heat. Here, we develop ultra-lightweight, InGaP/GaAs tandem with dual-function...
Fabrication of high quantum efficiency nanoscale device is challenging due to increased carrier loss at surface. Low dimensional materials such 0D dots and 2D have been widely studied mitigate the loss. Here, we demonstrate a strong photoluminescence enhancement from graphene/III-V dot mixed-dimensional heterostructures. The distance between graphene in 2D/0D hybrid structure determines degree radiative recombination 80% 800% compared only structure. Time-resolved decay also shows lifetimes...
Abstract 2D materials such as graphene hold significant potential for optoelectronic applications due to their unique surface properties and strong light‐matter interaction. Despite the promise, achieving high‐performance photonic devices using alone remains challenging, therefore, integrating with different dimensional semiconductors has emerged an alternative approach enhance device functionality. Here, p ‐type graphene/InAs quantum dot (QD)/ n GaAs mixed‐dimensional heterojunctions are...
We report on fabrication and characterization of high-quality 32 × GaAs photodetector (PD) arrays Si substrates fabricated by wafer bonding epitaxial lift-off (ELO) techniques. Fabricated PD showed good crystal quality with Raman spectra X-ray diffraction measurement. Also, pitch scaling gave us faster ELO process time as well high-density arrays. Furthermore, we investigated electrical optical characteristics pin substrates. Especially, the components dark current were also evaluated,...
We propose a new Ge waveguide platform on Si substrates using F- and Y-based insulator cladding such as CaF2 Y2O3 , which have small refractive index, broad transparency range, high thermal conductivity. First, we verified the by optical mode simulation, showing that Mid-infrared (MID-IR) light is well confined in proposed due to large differences indexes of insulators. also investigated aspects order quickly dissipate heat for stable source integration. It was found our provided better...
Abstract In this study, multicolor photodetectors (PDs) fabricated by using bulk p-i-n-based visible GaAs and near-infrared InGaAs structures were monolithically integrated through a high-throughput epitaxial lift-off (ELO) process. To perform detection in structures, PDs transferred onto Y 2 O 3 bonding layer to simultaneously detect photons minimize the optical loss. As result, it was found that top PD bottom vertically aligned without tilting x-ray diffraction (XRD) measurement. A...
Bi-layered hybrid nanostructures of polythiophene (PTh) and metal nanotubes are fabricated by a sequential electrochemical synthetic method. Huge enhancement photoluminescence PTh single coated with nanometer-scale Cu, Ni, or Co is observed using laser confocal microscope, can be explained the effect surface plasmon resonance. Bright light emission from strand PTh/Cu nanotube (see figure).
Epitaxial growth of III–V materials on Si is a promising approach for large-scale, relatively low-cost, and high-efficiency Si-based multi-junction solar cells. Several micron-thick compositionally graded buffers are typically grown to reduce the high threading dislocation density that arises due lattice mismatch between Si. Here, we show optically transparent n-In0.1Al0.9As/n-GaAs strained layer superlattice filter layers can be used in GaAs buffer while maintaining thickness below 2 μm....
Remnant lipoproteins (RLPs) are products of partially catabolized chylomicrons and very-low-density lipoprotein, from which some triglycerides have been removed. These particles smaller denser than the parent believed to be strongly atherogenic. We explored association between RLP cholesterol (RLP-C) ischemic stroke, including stroke subtypes.A cohort 142 patients (90 men 52 women; age, 65.2±12.8 years, mean±SD) was enrolled; all had acute infarcts confirmed by diffusion-weighted MRI,...
We report the fabrication of quantum dot infrared photodetectors (QDIPs) on silicon (Si) substrates by means metal wafer bonding and an epitaxial lift-off process. According to photoluminescence (PL) x-ray diffraction measurements, QDIP layer was transferred onto Si substrate without degradation crystal quality or residual strain. In addition, from PL results, we found that optical cavity formed because Pt/Au material served as back mirror facet GaAs/air front mirror. The device performance...
The high optical responsivity of the InAlAs-InGaAs metamorphic high-electron mobility transistor on GaAs substrate with composite channels is reported. Experimental results verify that photovoltaic effect causing effective decrease threshold voltage responsible for photoresponse to a 1.55-μm illumination.
Monolithic 3-D integration has emerged as a promising technological solution for traditional transistor scaling limitations and interconnection bottleneck. The challenge we must overcome is processing temperature limit top side devices in order to ensure proper performance of bottom devices. To solve this problem, developed low III–V Ge layer stacking process using wafer bonding epitaxial lift-off, since these materials can be processed at provide extended opportunity/functionality (sensor,...