Dong‐Seon Lee

Gwangju Institute of Science and Technology

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Trends

Author Order

Document Type

Co-Authors

A. J. Steckl

University of Cincinnati

Jung‐Hong Min

Gwangju Institute of Science and Technology

Woo‐Lim Jeong

Gwangju Institute of Science and Technology

Si‐Young Bae

Korea Institute of Ceramic Engineering and Technology

Jae‐Phil Shim

Korea Advanced Nano Fab Center

J. M. Zavada

New York University

Jin Hyeok Kim

Chonnam National University

Chang‐Mo Kang

Korea Institute of Radiological and Medical Sciences

Hiroshi Amano

Nagoya University

Seung‐Hyun Mun

Gwangju Institute of Science and Technology

Cooperative Institutions

Gwangju Institute of Science and Technology

167

Seoul National University

Government of the Republic of Korea

Korea Advanced Institute of Science and Technology

Samsung (South Korea)

Gwangju University

Sungkyunkwan University

Yonsei University

Hanyang University

Korea Institute of Science and Technology

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Field

Large-scale and high-quality III-nitride membranes through microcavity-assisted crack propagation by engineering tensile-stressed Ni layers

Opto-Electronic Science (2022)

Jung‐Hong Min Kwang Jae Lee Tae-Hoon Chung Jung‐Wook Min Kuang‐Hui Li

Epitaxially grown III-nitride alloys are tightly bonded materials with mixed covalent-ionic bonds. This tight bonding presents tremendous challenges in developing III-nitride membranes, even though semiconductor membranes can provide numerous advantages by removing thick, inflexible, and costly substrates. Herein, cavities with various sizes were introduced by overgrowing target layers, such as undoped GaN and green LEDs, on nanoporous templates prepared by electrochemical etching of n-type GaN. The large primary interfacial toughness was effectively reduced according to the design of the cavity density, and the overgrown target layers were then conveniently exfoliated by engineering tensile-stressed Ni layers. The resulting III-nitride membranes maintained high crystal quality even after exfoliation due to the use of GaN-based nanoporous templates with the same lattice constant. The microcavity-assisted crack propagation process developed for the current III-nitride membranes forms a universal process for developing various kinds of large-scale and high-quality semiconductor membranes.

Nanoporous

10.29026/oes.2022.220016

Cite

Citations (8)

Monolithic integration of AlGaInP-based red and InGaN-based green LEDs via adhesive bonding for multicolor emission

Scientific Reports (2017)

Chang‐Mo Kang Seok-Jin Kang Seung‐Hyun Mun Soo-Young Choi Jung‐Hong Min

In general, to realize full color, inorganic light-emitting diodes (LEDs) are diced from respective red-green-blue (RGB) wafers consisting of inorganic crystalline semiconductors. Although this conventional method can realize full color, it is limited when applied to microdisplays requiring high resolution. Designing a structure emitting various colors by integrating both AlGaInP-based and InGaN-based LEDs onto one substrate could be a solution to achieve full color with high resolution. Herein, we introduce adhesive bonding and a chemical wet etching process to monolithically integrate two materials with different bandgap energies for green and red light emission. We successfully transferred AlGaInP-based red LED film onto InGaN-based green LEDs without any cracks or void areas and then separated the green and red subpixel LEDs in a lateral direction; the dual color LEDs integrated by the bonding technique were tunable from the green to red color regions (530-630 nm) as intended. In addition, we studied vertically stacked subpixel LEDs by deeply analyzing their light absorption and the interaction between the top and bottom pixels to achieve ultra-high resolution.

Subpixel rendering

RGB color model

Red Color

10.1038/s41598-017-11239-4

Cite

Citations (45)

Strategy toward the fabrication of ultrahigh-resolution micro-LED displays by bonding-interface-engineered vertical stacking and surface passivation

Nanoscale (2019)

Dae‐Myeong Geum Seong Kwang Kim Chang‐Mo Kang Seung‐Hyun Moon Jihoon Kyhm

In this study, we proposed a strategy to fabricate vertically stacked subpixel (VSS) micro-light-emitting diodes (μ-LEDs) for future ultrahigh-resolution microdisplays. At first, to vertically stack the LED with different colors, we successfully adopted a bonding-interface-engineered monolithic integration method using SiO2/SiNx distributed Bragg reflectors (DBRs). It was found that an intermediate DBR structure could be used as the bonding layer and color filter, which could reflect and transmit desired wavelengths through the bonding interface. Furthermore, the optically pumped μ-LED array with a pitch of 0.4 μm corresponding to the ultrahigh-resolution of 63 500 PPI could be successfully fabricated using a typical semiconductor process, including electron-beam lithography. Compared with the pick-and-place strategy (limited by machine alignment accuracy), the proposed strategy leads to the fabrication of significantly improved high-density μ-LEDs. Finally, we systematically investigated the effects of surface traps using time-resolved photoluminescence (TRPL) and two-dimensional simulations. The obtained results clearly demonstrated that performance improvements could be possible by employing optimal passivation techniques by diminishing the pixel size for fabricating low-power and highly efficient microdisplays.

Passivation

Subpixel rendering

10.1039/c9nr04423j

Cite

Citations (48)

Gain without inversion in interband transitions of semiconductor quantum wells from a single-particle perspective

Physical review. B, Condensed matter (1996)

Dong‐Seon Lee Kevin J. Malloy

The quantum interferences arising in three-level atomic systems are investigated in analogous asymmetric semiconductor quantum well structures. These investigations lead to the conditions necessary for induced zero absorption and gain without population inversion in interband transitions. Asymmetric quantum well configurations are proposed and analyzed for induced zero absorption and gain without inversion using a single-particle density-matrix approach. This density-matrix approach is described and shown to give the steady-state solutions for absorption and gain without the approximations required for perturbative or iterative methods. Both excitonic and continuum transitions are examined using typical semiconductor parameters with excitonic transitions contributing the largest fraction of gain without inversion. While interband transitions differ from intraband and atomic transitions, results for the proposed quantum well configurations validate the basic concept of inversionless gain in semiconductors and point the way to ultralow threshold semiconductor microlasers. \textcopyright{} 1996 The American Physical Society.

Population inversion

Density matrix

10.1103/physrevb.53.15749

Cite

Citations (10)

EFFECTS OF EXTREME TIDAL RANGE ON CHARACTERISTICS OF POLYCHLORINATED BIPHENYL DISTRIBUTION IN SEDIMENT OF INDUSTRIAL INCHEON NORTH HARBOR, KOREA

Environmental Toxicology and Chemistry (2000)

Seung K. Kim Dong‐Seon Lee Jae Ryoung Oh Sung Hyun Kahng

This study investigated the influence of the high tidal range on the polychlorinated biphenyl (PCB) levels and the compositional characteristics in the sediments of the North Incheon Harbor basin, Korea. The results indicated that the high tidal range could induce complicated effects on the distribution and the compositional characteristics of PCBs. Significant differences in the total PCB concentration were found between the tidal and subtidal zones. Higher total PCBs in the tidal zone established a total PCB gradient in a transversal direction along the harbor basin. The large tidal range created tidal currents strong enough to grade the sediment particles, establishing a gradient of total PCBs corresponding to an observed sediment particle size along the longitudinal direction of the basin. Heterogeneous congener patterns were observed in some parts of the tidal zone where diverse physicochemical and microbiological conditions are to be expected. However, tidally driven, active sediment transport promoted spatial homogeneity in the congener pattern. Sedimentation rate of suspended solids appeared to overwhelm any induced heterogeneity in the PCB congener pattern. Consequently, the congener pattern within the harbor basin was fairly uniform and similar to that of a dominant input source.

Congener

Polychlorinated biphenyl

Sedimentation

Tidal current

Biphenyl

Tidal range

10.1897/1551-5028(2000)019<2448:eoetro>2.3.co;2

Cite

Citations (0)

Highly elongated vertical GaN nanorod arrays on Si substrates with an AlN seed layer by pulsed-mode metal–organic vapor deposition

CrystEngComm (2016)

Si‐Young Bae Byung Oh Jung Kaddour Lekhal Sang Yun Kim Jeong Yong Lee

Precisely controlled morphology of GaN nanorods was obtained on a thin AlN seed layer and their height increased as the diameter of the mask openings decreased.

Nanorod

Deposition

Morphology

10.1039/c5ce02056e

Cite

Citations (36)

Growth, Fabrication, and Characterization of GaN-based Columnar LEDs

Duk‐Jo Kong Chang‐Mo Kang Si‐Young Bae Dong‐Seon Lee

GaN micro- (or nano-) column structures have been studied in an attempt to enhance the LED performance by improving the light extraction and reducing the strain due to the large lattice mismatch between GaN and InGaN. Nowadays columnar LEDs are drawing attention as a candidate for a multicolor emission source as illustrated in Fig. 1. Though numerous studies have focused on selective area growth, the top-down approach has often been the subject of study since it can realize a columnar structure more easily than when using the bottom-up method. However, predominant issue in the top-down approach is dry-etch damage resulting from the inductively coupled plasma (ICP) and reactive ion etching (RIE) systems. According to the previous reports the damage usually results in the increase in the sheet-resistance of GaN, along with the decrease in the reverse breakdown voltage and the reductions in the Schottky barrier height in the diodes formed on GaN. The roughened sidewall after etching also exhibited higher series resistance in the device and deteriorates the electrical characteristics. KOH treatment has been found to improve the electrical characteristics through the removal of the damaged region and providing the vertical profile in the sidewall with a smooth surface. Moreover, the size control of GaN micro- (or nano-) columns also becomes possible by adopting the KOH treatment.

Dry etching

Wide-bandgap semiconductor

10.1364/jsap.2014.20p_c1_1

Cite

Citations (0)

Advanced Graphene/Metal-Mesh Hybrid Transparent Electrodes via Ultraviolet (UV)–Ozone Treatment for UV-Range Optoelectronic Devices

ACS Applied Electronic Materials (2024)

Je-Sung Lee Jung‐Hong Min Kyung-Pil Kim Woo‐Lim Jeong Hoe-Min Kwak

The fabrication of advanced graphene/metal-mesh hybrid transparent electrodes (TEs) suitable for ultraviolet (UV)-range optoelectronic applications is reported herein, employing UV–ozone treatment. The UV–ozone treatment of transferred graphene is adopted to simultaneously enable oxidation doping and taint removal from the graphene surface and obtain the supplementary benefit of optical transmittance enhancement. Furthermore, the changes in the physical and chemical properties of graphene under different UV–ozone-treated times were characterized using Raman, X-ray/UV photoelectron spectroscopy, Hall measurements, and the transmission line method. Subsequently, hybrid structures combining various UV–ozone-treated graphene samples with a metal-mesh were tested as TEs in gallium nitride-based 375 nm near-UV light-emitting diodes (LEDs). Results indicate a noteworthy enhancement in light output power: a 48.3% increase relative to an untreated LED and an 18.3% increase compared to a conventional indium tin oxide (ITO)-based LED, particularly after 300 s of UV–ozone treatment. The present study provides a practical approach to overcome the limitations of existing ITO TEs for UV applications, thereby facilitating the future commercialization of graphene-based optoelectronic devices.

Ultraviolet

Indium tin oxide

10.1021/acsaelm.4c00652

Cite

Citations (0)

Resistive switching characteristics of metal oxide for nonvolatile memory applications

Rui Dong M. Hasan Hyejung Choi Dong‐Seon Lee M. B. Pyun

The resistance switching characteristics of several metal oxides has been reported recently for nonvolatile memory applications (NVM). However, various issues such as the switching mechanisms, switching uniformity, scalability and reproducibility have not yet been solved. In this paper, we discuss the recent progress of switching mechanisms and switching behaviors of various materials.

Non-Volatile Memory

Fast switching

Switching time

10.1109/icsict.2008.4734691

Cite

Citations (0)

Combined Effect of Carrier Localization and Polarity in InxGa1−xN/GaN Quantum Wells

Journal of Nanoscience and Nanotechnology (2014)

H. Y. Hwang Sang-Bae Choi Hoonill Jeong Dong‐Seon Lee Young-Dahl Jho

The influence of carrier localization and polarization-induced electric fields on the spectral variation of photoluminescence was comparatively studied in polar and semipolar InxGa1-x N/GaN strained quantum wells embedded in p-i-n diodes. Two representative structures with x = 0.16 for polar (0001) diodes and potential fluctuations for semipolar diodes grown along (1122) direction have been investigated with a reverse bias up to -4 V. From the s-shaped spectral shift as a function of temperature, the existence of single and triple localization traps was confirmed in polar and semipolar diodes. Within our bias range, we observed the monotonic blueshift with reverse bias in the polar sample, indicating that the carriers are laterally localized and thus influenced by the vertical piezoelectric fields. In clear contrast, the semipolar sample showed the blueshift of localized states only at low temperatures, while the deepest localization features were found at the highest available temperatures, overriding the influence of thermal activation and polarization fields.

Blueshift

Polarity (international relations)

10.1166/jnn.2015.10369

Cite

Citations (2)