Updated on 2024/03/18

写真a

 
Heajeong Cheong
 
Organization
Graduate School of Engineering Graduate School of Engineering Assistant Professor
Graduate School
Graduate School of Engineering
Undergraduate School
School of Engineering
Title
Assistant Professor
Contact information
メールアドレス
External link

Degree 1

  1. 博士(学術) ( 2019.3   東京工業大学 ) 

Research Interests 1

  1. LED,IGZO,マイクロ波

Research Areas 1

  1. Manufacturing Technology (Mechanical Engineering, Electrical and Electronic Engineering, Chemical Engineering) / Electron device and electronic equipment

Current Research Project and SDGs 1

  1. GaNを利用したマイクロLEDの開発

Research History 6

  1. Nagoya University   Assistant Professor

    2020.5

  2. Nagoya University

    2016.11 - 2020.3

  3. 産業技術総合研究所   フレキシブルエレクトロニクス研究センター   特別研究員

    2013.4 - 2015.12

  4. 産業技術総合研究所   ナノシステム研究部門   特別研究員

    2012.10 - 2013.3

  5. 産業技術総合研究所   環境化学技術研究部門   研究員

    2011.10 - 2012.5

  6. Samsung Electronics Co., Ltd.   System LSI C&M PA

    2009.3 - 2011.3

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    Country:Korea, Republic of

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Education 3

  1. Tokyo Institute of Technology

    2004.10 - 2009.3

  2. 東亜大学校大学院(韓国)   自然科学部   修士課程新素材物理専攻

    2001.3 - 2003.2

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    Country: Korea, Republic of

  3. 東亜大学校(韓国)   自然科学部   新素材物理学科 

    1999.9 - 2001.2

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    Country: Korea, Republic of

Committee Memberships 2

  1.   極低温実験室運営委員会委員  

    2020.4   

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    Committee type:Other

  2.   VBL運営委員会  

    2020.4   

Awards 2

  1. The 2nd IEEE Tokyo Student workshop、オリジナリティ賞受賞

    2005.12   東京工業大学   100年後の光デバイス

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    Award type:Award from Japanese society, conference, symposium, etc.  Country:Japan

  2. 交流研究助成金

    2005.3   財団法人丸文研究交流財団   シリコン量子ドット発光デバイスの研究

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    Award type:Award from publisher, newspaper, foundation, etc.  Country:Japan

 

Papers 24

  1. Dislocation Suppresses Sidewall-Surface Recombination of Micro-LEDs Reviewed

    Jeong-Hwan Park, Markus Pristovsek, Wentao Cai, Heajeong Cheong, Chang-Mo Kang, Dong-Seon Lee, Tae-Yeon Seong, Hiroshi Amano

    laser and photonics reviews     page: 2300199 (1 of 8) - 2300199 (8 of 8)   2023.6

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    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: https://doi.org/10.1002/lpor.202300199

  2. Impact of Sidewall Conditions on Internal Quantum Efficiency and Light Extraction Efficiency of Micro-LEDs Reviewed

    Jeong-Hwan Park, Markus Pristovsek, Wentao Cai, Heajeong Cheong, Atsushi Tanaka, Yuta Furusawa, Dong-Pyo Han, Tae-Yeon Seong, Hiroshi Amano

    Advanced Optical Materials     page: 2203128-1 - 2203128-9   2023.3

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    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: https://doi.org/10.1002/adom.202203128

  3. The effect of dry etching condition on the performance of blue micro light-emitting diodes with reduced quantum confined Stark effect epitaxial layer Reviewed

    Jeong-Hwan Park, Wentao Cai,Heajeong Cheong,Yasuhisa Ushida, Da-Hoon Lee, Yuto Ando, Yuta Furusawa, Yoshio Honda, Dong-Seon Lee,Tae-Yeon Seong, and Hiroshi Amano

    Journal of Applied Physics     page: 153104   2022.4

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    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: https://doi.org/10.1063/5.0085384

  4. Dislocation Suppresses Sidewall-Surface Recombination of Micro-LEDs

    Park, JH; Pristovsek, M; Cai, WT; Cheong, HJ; Kang, CM; Lee, DS; Seong, TY; Amano, H

    LASER & PHOTONICS REVIEWS   Vol. 17 ( 10 )   2023.10

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    Publisher:Laser and Photonics Reviews  

    Nonradiative recombination rate that consists of dislocation-related nonradiative recombination rate (A0) and surface recombination rate (As) is one of the major parameters determining the performance of microlight-emitting diodes (µLEDs). Recent demonstrations improving the efficiency of blue InGaN or red AlGaInP µLEDs using specific methods such as atomic layer deposition or chemical treatment confirm the suppression of As. However, it is hardly found that those methods effectively improve the efficiency of red InGaN µLEDs so far. Here, it is discovered that the dislocation leads to an ineffective As. First, an intrinsic As degrades the external quantum efficiency (EQE) of blue InGaN µLEDs, resulting in EQE decreases with shrinking size. Second, panchromatic cathodoluminescence finds evidence that most of the carriers can be trapped before reaching the sidewall due to high A0. This results in shortened diffusion length of carriers and reduces the number of carriers reaching the sidewall. Consequently, the opposite trend of increasing EQE with shrinking size occurs in the case of red InGaN µLEDs due to an ineffective As. Furthermore, an 8.3 nm quantum well of InGaN with 13% Indium content that can reach a ≈690 nm wavelength at the low current is shown.

    DOI: 10.1002/lpor.202300199

    Web of Science

    Scopus

  5. Impact of Sidewall Conditions on Internal Quantum Efficiency and Light Extraction Efficiency of Micro-LEDs

    Park, JH; Pristovsek, M; Cai, WT; Cheong, HJ; Tanaka, A; Furusawa, Y; Han, DP; Seong, TY; Amano, H

    ADVANCED OPTICAL MATERIALS   Vol. 11 ( 10 )   2023.5

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    Publisher:Advanced Optical Materials  

    The sidewall condition is a key factor determining the performance of micro-light emitting diodes (µLEDs). In this study, equilateral triangular III-nitride blue µLEDs are prepared with exclusively m-plane sidewall surfaces to confirm the impact of sidewall conditions. It is found that inductively coupled plasma-reactive ion etching (ICP-RIE) causes surface damages to the sidewall and results in rough surface morphology. As confirmed by time-resolved photoluminescence (TRPL) and X-ray photoemission spectroscopy (XPS), tetramethylammonium hydroxide (TMAH) eliminates the etching damage and flattens the sidewall surface. After ICP-RIE, 100 µm2-µLEDs yield higher external quantum efficiency (EQE) than 400 µm2-µLEDs. However, after TMAH treatment, the peak EQE of 400 µm2-µLEDs increases by ≈10% in the low current regime, whereas that of 100 µm2-µLEDs slightly decreases by ≈3%. The EQE of the 100 µm2-µLEDs decreases after TMAH treatment although the internal quantum efficiency (IQE) increases. Further, the IQE of the 100 µm2-µLEDs before and after TMAH treatment is insignificant at temperatures below 150 K, above which it becomes considerable. Based on PL, XPS, scanning transmission electron microscopy, and scanning electron microscopy results, mechanisms for the size dependence of the EQE of µLEDs are explained in terms of non-radiative recombination rate and light extraction.

    DOI: 10.1002/adom.202203128

    Web of Science

    Scopus

  6. Red emission from InGaN active layer grown on nanoscale InGaN pseudosubstrates Reviewed

    Cai, WT; Wang, J; Park, JH; Furusawa, Y; Cheong, HJ; Nitta, S; Honda, Y; Pristovsek, M; Amano, H

    JAPANESE JOURNAL OF APPLIED PHYSICS   Vol. 62 ( 2 )   2023.2

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:Japanese Journal of Applied Physics  

    We demonstrated nanoplatelet In x Ga1−x N pseudosubstrates with In content varying from 0 to 0.3 on low-dislocation-density GaN substrates. These nanoplatelets efficiently relax in-plane strain, thus allowing for the use of a thick active layer to reduce built-in polarization. The 15 nm thick InGaN active layers grown under the same conditions on these nanoplatelets showed a remarkable cathodoluminescence redshift from 460 to 617 nm, suggesting enhanced In incorporation efficiency in InGaN nanoplatelets with higher In content. Moreover, the 617 nm-emitting sample presented an imperceptible blueshift under excitation-power-dependent photoluminescence, indicating a weak polarization field introduced by the high-In-content pseudosubstrates and the thick active layer.

    DOI: 10.35848/1347-4065/acb74c

    Web of Science

    Scopus

  7. High In content nitride sub-micrometer platelet arrays for long wavelength optical applications

    Cai, WT; Furusawa, Y; Wang, J; Park, JH; Liao, YQ; Cheong, HJ; Nitta, S; Honda, Y; Pristovsek, M; Amano, H

    APPLIED PHYSICS LETTERS   Vol. 121 ( 21 )   2022.11

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    Publisher:Applied Physics Letters  

    We demonstrate high, up to 30% In content InGaN sub-micrometer platelets on GaN by metalorganic vapor phase epitaxy. These InGaN platelets were selectively grown on flat GaN seeds formed in sub-micrometer-scale openings in a SiNx mask. The platelets were highly uniform without any dislocations or pits, with an atomically flat (0001) surface. The typical height was ∼120 nm, which significantly exceeded the normal critical layer thickness of a c-plane InGaN film. The strain state was comprehensively characterized by microbeam x-ray diffraction and transmission electron microscopy. Due to a gradual elastic relaxation of strain, the In content increased almost linearly from bottom to top because of the strong strain-dependent In incorporation. These platelets can serve as high-quality strain-relaxed templates for long wavelength micro-light-emitting diodes.

    DOI: 10.1063/5.0120723

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  8. Interplay of sidewall damage and light extraction efficiency of micro-LEDs

    Park, JH; Pristovsek, M; Cai, WT; Cheong, H; Kumabe, T; Lee, DS; Seong, TY; Amano, H

    OPTICS LETTERS   Vol. 47 ( 9 ) page: 2250 - 2253   2022.5

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    Language:English   Publisher:Optics Letters  

    This Letter describes the impact of shape on micro light-emitting diodes (µLEDs), analyzing 400 µm2 area µLEDs with various mesa shapes (circular, square, and stripes). Appropriate external quantum efficiency (EQE) can yield internal quantum efficiency (IQE) which decreases with increasing peripheral length of the mesas. However, light extraction efficiency (ηe) increased with increasing mesa periphery. We introduce analysis of Jpeak (the current at peak EQE) since it is proportional to the non-radiative recombination. Etching the sidewalls using tetramethylammonium hydroxide (TMAH) increased the peak EQE and decreased the sidewall dependency of Jpeak. Quantitatively, the TMAH etching reduced non-radiative surface recombination by a factor of four. Hence, shrinking µLEDs needs an understanding of the relationship between non-radiative recombination and ηe, where analyzing Jpeak can offer new insights.

    DOI: 10.1364/OL.456993

    Web of Science

    Scopus

    PubMed

  9. The effect of dry etching condition on the performance of blue micro light-emitting diodes with reduced quantum confined Stark effect epitaxial layer

    Park, JH; Cai, W; Cheong, H; Ushida, Y; Lee, DH; Ando, Y; Furusawa, Y; Honda, Y; Lee, DS; Seong, TY; Amano, H

    JOURNAL OF APPLIED PHYSICS   Vol. 131 ( 15 )   2022.4

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    Publisher:Journal of Applied Physics  

    As the size of micro light-emitting diodes (μLEDs) decreases, μLEDs encounter etching damage especially at the sidewalls that critically affects their properties. In this study, we investigated the influence of etching bias power (Pbias) on the performance of μLEDs and found that the current-voltage and light output-current characteristics of μLEDs were enhanced when Pbias was reduced. It was shown that at low Pbias, the chemical reaction between etching gas and gallium nitride, rather than ion sputtering, dominated the etching process, leading to low plasma damage and rough surface morphology. Additionally, to understand the etching-induced surface roughening behaviors, various substrates with different threading dislocation densities were treated at low Pbias. It was found that for the sample (with p-contact size of 10 × 10 μm2), the efficiency droop was approximately 20%, although the current reached 10 mA due most probably to the suppressed polarization effect in the quantum well. It was further observed that the external quantum efficiency (EQE) was dependent on Pbias, where the lowest Pbias yielded the highest maximum EQE, indicating that the plasma damage was mitigated by reducing Pbias. Optimization of dry etching and polarization-suppression conditions could pave the way for realizing high-performance and brightness μLEDs for next-generation displays.

    DOI: 10.1063/5.0085384

    Web of Science

    Scopus

  10. Effect of substrate misorientation on the concentration of impurities and surface morphology of an epitaxial GaN layer on N-polar GaN substrate by MOVPE Reviewed

    Nagamatsu, K; Ando, Y; Kono, T; Cheong, H; Nitta, S; Honda, Y; Pristovsek, M; Amano, H

    JOURNAL OF CRYSTAL GROWTH   Vol. 512   page: 78 - 83   2019.4

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    Language:Japanese   Publishing type:Research paper (scientific journal)   Publisher:Journal of Crystal Growth  

    This study examines the effect of (0 0 0 −1) GaN substrate misorientation on the residual impurities and surface morphology of N-polar GaN grown by metalorganic vapor-phase epitaxy. Carbon, silicon, and oxygen concentrations decreased with increasing GaN substrate misorientation angle, with the lowest impurity concentration achieved for a misorientation angle of 2° toward the m-axis, with 6 × 10 15 cm −3 carbon, 6 × 10 15 cm −3 silicon, and 4 × 10 17 cm −3 oxygen atoms. The oxygen concentration was measured at a depth of 0.5 μm below the wafer surface, and the oxygen concentration decreased with increasing thickness. The incorporation of carbon and oxygen revealed a strong dependence on the misorientation angle. The step distance height of the steps parallel to the [1 1 −2 0] direction (or perpendicular to the [1 −1 0 0] m-direction) was confirmed to be a double-height layer step. This phenomenon indicated that m-direction steps are stable for N-polar growth in GaN. In cases of large misorientation toward the m-axis in of the GaN substrate it was difficult to control the misorientation perpendicular to the nominal direction leading to a-axis direction by wafer bowing at wafer manufacturing. Therefore, step-bunching was generated for each symmetric m-axis due to an increase in the compound's off-angle, thus causing the surface roughness to become large.

    DOI: 10.1016/j.jcrysgro.2019.02.013

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  11. Suitability of Copper Nitride as a Wiring Ink Sintered by Low-Energy Intense Pulsed Light Irradiation Reviewed

    Nakamura, T; Cheong, HJ; Takamura, M; Yoshida, M; Uemura, S

    NANOMATERIALS   Vol. 8 ( 8 )   2018.8

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:Nanomaterials  

    Copper nitride particles have a low decomposition temperature, they absorb light, and are oxidation-resistant, making them potentially useful for the development of novel wiring inks for printing circuit boards by means of intense pulsed light (IPL) sintering at low-energy. Here, we compared the thermal decomposition and light absorption of copper materials, including copper nitride (Cu3N), copper(I) oxide (Cu2O), or copper(II) oxide (CuO). Among the copper compounds examined, copper nitride had the second highest light absorbency and lowest decomposition temperature; therefore, we concluded that copper nitride was the most suitable material for producing a wiring ink that is sintered by means of IPL irradiation. Wiring inks containing copper nitride were compared with those of wiring inks containing copper nitride, copper(I) oxide, or copper(II) oxide, and copper conversion rate and sheet resistance were also determined. Under low-energy irradiation (8.3 J cm−2), copper nitride was converted to copper at the highest rate among the copper materials, and provided a sheet resistance of 0.506 Ω·sq−1, indicating that copper nitride is indeed a candidate material for development as a wiring ink for low-energy intense pulsed light sintering-based printed circuit board production processes.

    DOI: 10.3390/nano8080617

    Web of Science

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  12. <i>m</i>-Plane GaN Schottky Barrier Diodes Fabricated With MOVPE Layer on Several Off-Angle <i>m</i>-Plane GaN Substrates

    Tanaka, A; Ando, Y; Nagamatsu, K; Deki, M; Cheong, H; Ousmane, B; Kushimoto, M; Nitta, S; Honda, Y; Amano, H

    PHYSICA STATUS SOLIDI A-APPLICATIONS AND MATERIALS SCIENCE   Vol. 215 ( 9 )   2018.5

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:Physica Status Solidi (A) Applications and Materials Science  

    In this study, GaN m-plane Schottky barrier diodes are fabricated by metalorganic vapor-phase epitaxy (MOVPE) on several off-angle gallium nitride (GaN) substrates, and the off-cut angle dependence of impurity incorporation is investigated. We show that the MOVPE layer on the substrate inclined 5° toward the [000–1] direction has extremely low impurity incorporation. These results provide important suggestions for the fabrication of m-plane power devices.

    DOI: 10.1002/pssa.201700645

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  13. Flexible InGaZnO TFT devices obtained via humid-UV irradiation with an aqueous-fluoroalcoholic precursor Reviewed

    Shintaro Ogura, Heajeong Cheong, Sei Uemura, Hirobumi Ushijima and Nobuko Fukuda.

    Flexible and Printed Electronics     2016.11

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    Language:English   Publishing type:Research paper (scientific journal)  

  14. Solution-processed hybrid organic-inorganic complementary thin-film transistor inverter Reviewed

    Heajeong Cheong, Kazunori Kuribara, Shintaro Ogura, Nobuko Fukuda, Manabu Yoshida, Hirobumi Ushijima and Sei Uemura,

    Jpn. J. Appl. Phys     2016.4

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    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

  15. Rapid preparation of solution-processed InGaZnO thin film by microwave irradiation and photoirradiation Reviewed

    Heajeong Cheong, Shintaro Ogura, Hirobumi Ushijima, Manabu Yoshida, Nobuko Fukuda, and Sei Uemura,

    AIP advanced     2015.3

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    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

    DOI: https://doi.org/10.1063/1.4922512

  16. Investigation of Low Temperature Process of Solution Processed Oxide Semiconductor as a Thin Film Transistor Reviewed

    Hea Jeong Cheong, Shintaro Ogura, Manabu Yoshida, Hirobumi Ushijima, Nobuko Fukuda, Sei Uemura

    J. Photopolym. Sci. Techol     2015

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    Authorship:Lead author   Language:English  

  17. Effect of Microwave Annealing on Oxide-Semiconductor-Precursor Ink Reviewed

    Hea Jeong Cheong, Nobuko Fukuda, Shintaro Ogura, Heisuke Sakai, Yoshida Manabu, Takehito Kodzasa, Hideo Tokuhisa, Kazuhiko Tokoro, Kazuhiko Takeuchi, Ritsuko Nagahata, Takashi Nakamura, and Sei Uemura

    J. Photopolym. Sci. Technol.     2014

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    Authorship:Lead author   Language:English  

  18. Characterization of an Oxide Semiconductor Prepared by Microwave Sintering Reviewed

    Hea Jeong Cheong, Nobuko Fukuda, Heisuke Sakai, Shintaro Ogura, Kazuhiko Takeuchi, Ritsuko Nagahata, Sei Uemura

    Jpn. J. Appl. Phys     2014

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    Authorship:Lead author   Language:English  

  19. Visible Electroluminescence from Spherical-shaped Silicon Nanocrystals Reviewed

    Hea Jeong Cheong, Atsushi Tanaka, Daihei Hippo, Koichi Usami, Yoshishige Tsuchiya, Hiroshi Mizuta, and Shunri Oda

    Jpn. J. Appl. Phys.     2008

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    Authorship:Lead author   Language:English  

  20. Growth of highly Luminescence Silicon Nanocrystals by Rapid Thermal Chemical Vapor Deposition Reviewed

    Yong Kim, Hea Jeong Cheong, Jung Hyun Kang, Jae Kwon Kim, Tae Hun Chung, Hong Jun Bark, Jae-Yel Yi

    Key. Eng. Mat     2005

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    Language:English  

  21. Formation of luminescent Si nanocrystals by high-temperature rapid thermal chemical vapor deposition Reviewed

    Hea Jeong Cheong, Jung Hyun Kang, Jae Kwon Kim, Yong Kim, Tae Hun Chung, Hong Jun Bark, Jae-Yel Yi

    Appl. Phys. Lett.     2003

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    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

    DOI: https://doi.org/10.1063/1.1616646

  22. Rapid Thermal Annealing Effect on Charge Storage Characteristics in MOS Capacitor with Ge Nanocrystals Reviewed

    Jae Kwon Kim, Hea Jeong Cheong, Kyung Hwa Park, Yong Kim, Jae-Yel Yi and Hong Jun Bark, Yong Lee

    J. Kor. Phys. Soc.     2003

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    Language:English   Publishing type:Research paper (scientific journal)  

  23. Rapid-thermal-annealing effect on lateral charge loss in metal-oxide-semiconductor capacitors with Ge nanocrystals Reviewed

    Jae Kwon Kim, Hea Jeong Cheong, Yong Kim, Jae-Yel Yi, Hong Jun Bark, S. H. Bang and J. H. Cho

    Appl. Phys. Lett.     2003

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    Language:English   Publishing type:Research paper (scientific journal)  

  24. Charge retention characteristics in a metal-insulator-semiconductor capacitor containing Ge nanocrystal Reviewed

    Yong Kim, Hea Jeong Cheong, Kyung Hwa Park, Tae Hun Chung, Hong Jun Bark, Jae-Yel Yi, Suk, Hyun Bang, and Jin Hyung Cho

    Semicond. Sci. Technol.     2002

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    Language:English   Publishing type:Research paper (scientific journal)  

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Presentations 28

  1. GaNのマイクロ波アニーリングにおける加熱効率の評価と考察 International coauthorship

    中村 考志、鄭 恵貞、田中 敦之、天野 浩

    2023年第70回応用物理学会春季学術講演会  2023.3.16  公益社団法人 応用物理学会

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    Event date: 2023.3

    Language:Japanese   Presentation type:Poster presentation  

    Venue:東京   Country:Japan  

  2. The importance of sidewall conditions on the performance of micro LEDs International conference

    Jeong-Hwan Park, Markus Pristovsek, Wentao Cai, Heajeong Cheong, Atsushi Tanaka, Yuta Furusawa, Dong-Pyo Han, Tae-Yeon Seong, Hiroshi Amano

    2023.3.17 

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    Event date: 2023.3

    Language:English   Presentation type:Oral presentation (general)  

    Country:Japan  

  3. Relationship between sidewall damage and light extraction efficiency on the micro-LED International conference

    Jeong-Hwan Park, Markus Pristovsek, Wentao Cai, Heajeong Cheong, Takeru Kumabe, Dong-Seon Lee, Tae-Yeon Seong, Hiroshi Amano

    IWN2022 

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    Event date: 2022.10

    Language:English   Presentation type:Poster presentation  

    Country:Germany  

  4. Enhanced Indium Incorporation in full InGaN MQWs on High Indium Content InGaN Platelets International conference

    IWN2022 

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    Event date: 2022.10

    Language:English   Presentation type:Oral presentation (general)  

    Country:Germany  

  5. マイクロ波磁場による窒化ガリウム基板の急速アニーリング技術の開発と基板の特性評価 International coauthorship

    中村考志、西岡 将輝、鄭 恵貞、田中 敦之、天野 浩

    第83回応用物理学会秋季学術講演会  2022.9.20  公益社団法人 応用物理学会

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    Event date: 2022.9

    Language:Japanese   Presentation type:Poster presentation  

    Venue:東北   Country:Japan  

  6. "High In-Content InGaN Platelets as Underlayer for Light-Emitting Diodes Toward Long Wavelength Application "

    Wentao Cai, Yuta Furusawa, Jeong-Hwan Park, Heajeong Cheong, Shugo Nitta, Yoshio Honda, Hiroshi Amano

    The Electronic Materials Conference2022 

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    Event date: 2022.6 - 2022.7

    Language:English   Presentation type:Oral presentation (general)  

    Country:United States  

  7. Enhancing the External Quantum Efficiency of Micro-LEDs via Optimized Dry Etching Condition International conference

    Jeong-Hwan Park, Heajeong Cheong, Yasuhisa Ushida, Wentao Cai, Yuta Furusawa, Tae-Yeon Seong, Hiroshi Amano

    The Electronic Materials Conference 2022 

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    Event date: 2022.6 - 2022.7

    Language:English   Presentation type:Oral presentation (general)  

    Country:United States  

  8. Fabrication of micro-LED and HEMT on the same wafer for an active-matrix display International conference

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    Event date: 2022.4

    Language:English   Presentation type:Oral presentation (general)  

    Venue:JAPAN  

  9. High In-content InGaN Platelet as Underlayer for Light Emitting Diodes toward Long Wavelength Application International conference

    Cai Wentao

    International Conference on Materials and Systems for Sustainability2021  2021.11.5 

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    Event date: 2021.11 - 2021.1

    Language:English   Presentation type:Poster presentation  

    Venue:On-Line   Country:Japan  

  10. The effect of dry etching condition on the micro-LED International conference

    Jeong-hwan Park

    The 21st International Meeting on Information Display  2021.8.27 

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    Event date: 2021.8

    Language:English   Presentation type:Poster presentation  

    Venue:On-Line   Country:Korea, Republic of  

  11. シリコン量子ドットからの可視エレクトロルミネッセンスの観測

    鄭 恵貞

    第53回応用物理学関係連合講演会  2006.3 

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    Venue:武蔵工業大学世田谷キャンパス  

  12. サイズ制御したシリコン量子ドットからの可視エレクトロルミネッセンス

    鄭 恵貞

    第67回応用物理学会学術講演会  2006.9 

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    Venue:上智大学四谷キャンパス  

  13. ナノ結晶シリコンドット発光デバイスの断面構造解析と窒化膜を利用した高性能化の検討

    鄭 恵貞

    第68回応用物理学会学術講演会  2007.9 

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    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:北海道大学札幌キャンパス  

  14. 基板窒化処理によるシリコンナノ結晶ELデバイスの高性能化

    鄭 恵貞

    第69回応用物理学会学術講演会  2008.9 

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    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:中部大学三浦幸平メモリアルホール  

  15. マイクロ波加熱を利用した酸化物TFTの作製

    鄭 恵貞

    第74回応用物理学会春季学術講演会  2013.9 

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    Venue:同志社大学京田辺キャンパス  

  16. 酸化物半導体前駆体のインク化とマイクロ波焼成プロセスの開発

    鄭 恵貞

    第61回応用物理学会春季学術講演会  2014.3 

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    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:青山学院大学相模原キャンパス  

  17. 酸化物半導体の低温化・短時間焼成プロセスの検討

    鄭 恵貞

    第75回応用物理学会秋季学術講演会  2014.9 

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    Language:Japanese   Presentation type:Oral presentation (general)  

  18. 酸化物半導体を低温溶液プロセスで作製する際のマイクロ波及び真空紫外光照射効果の確認

    鄭 恵貞

    第62回応用物理学会春季学術講演会  2015.3 

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    Language:Japanese   Presentation type:Oral presentation (general)  

  19. 低温塗布IGZOを用いた有機半導体とのハイブリッドインバータの作製

    鄭 恵貞

    第76回応用物理学会秋季学術講演会  2015.9 

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    Language:Japanese   Presentation type:Oral presentation (general)  

  20. Visible Electroluminescence from Size-Controlled Silicon Quantum Dots International conference

    Heajeong Cheong

    Conference on Laser and Electro-Optics 2006  2006.5 

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    Language:English   Presentation type:Oral presentation (general)  

    Venue:California Long beach Convention center, (USA)  

  21. Light emission from size reduced nanocrystal silicon quantum dots International conference

    Heajeong Cheong

    Conference on Laser and Electro-Optics 2007  2007.5 

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    Language:English   Presentation type:Oral presentation (general)  

    Venue:Baltimore Convention Center, Maryland, (USA)  

  22. Characterization of an Oxide Semiconductor Prepared by Microwave Sintering International conference

    Heajeong Cheong

    International Conference on Flexible and Printed Electronics  2013.9 

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    Language:English   Presentation type:Oral presentation (general)  

    Venue:Jeju island, (Korea),  

  23. Effect of Microwave annealing on oxide-semiconductor-precursor Ink International conference

    Heajeong Cheong

    International Conference of Photopolymer Science and Technology  2014.6 

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    Language:English   Presentation type:Oral presentation (general)  

    Venue:Chiba (JAPAN)  

  24. Low temperature fabrication of oxide semiconductor thin film transistor by photo irradiation International conference

    Heajeong Cheong

    International Conference of Science and Technology of Synthetic Metals  2014.7 

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    Language:English   Presentation type:Oral presentation (general)  

    Venue:Turku (Finland)  

  25. Fabrication of solution-processed oxide semiconductor thin film transistors at low temperature International conference

    Hea Jeong Cheong

    International Conference on Flexible and Printed Electronics,  2014.10 

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    Language:English   Presentation type:Oral presentation (general)  

  26. Investigation of Low Temperature Process of Solution Processed Oxide Semiconductor as a Thin Film Transistor International conference

    Heajeong Cheong

    International Conference of Photopolymer Science and Technology  2015.6 

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    Language:English   Presentation type:Oral presentation (general)  

    Country:Japan  

  27. Solution-Processed Hybrid Organic–Inorganic Complementary Thin-Film Transistor Inverter International conference

    Heajeong Cheong

    International Conference on Solid State Devices and Materials  2015.9 

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    Language:English   Presentation type:Oral presentation (general)  

    Country:Japan  

  28. Fabrication of Hybrid Organic-Inorganic Complementary Inverter at Low Temperature”, International Conference on Flexible and Printed Electronics International conference

    Heajeong Cheong

    International Conference on Flexible and Printed Electronics  2015.10 

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    Language:English   Presentation type:Oral presentation (general)  

    Country:Taiwan, Province of China  

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Other research activities 3

  1. 萌芽的共創研究

    2023.7
    -
    2024.3

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    電場・磁場分離マイクロ波加熱によるGaNの再結晶化促進メカニズムの究明

  2. CIRFE若手活性化支援事業

    2021.7
    -
    2022.3

  3. 産総研-名古屋大学アライアンス事業

    2020.11
    -
    2022.3

Research Project for Joint Research, Competitive Funding, etc. 4

  1. Red発光Micro LED素子の開発 International coauthorship

    2023.6 - 2024.5

    共同研究  共同研究

    鄭恵貞, CAI Wentao, WANG Jia, HAN Qingyuan

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    Authorship:Coinvestigator(s)  Grant type:Collaborative (industry/university)

    Grant amount:\30000000 ( Direct Cost: \23077000 、 Indirect Cost:\6923000 )

  2. GaNの極性を利用したマイクロ波アニール(全く新規の独創的研究)

    2021.7 - 2022.3

    CIRFE若手活性化支援事業の研究費 

    鄭恵貞

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    Authorship:Principal investigator  Grant type:Other

    Grant amount:\2200000 ( Direct Cost: \2200000 )

  3. マイクロ波磁場加熱によるGaN薄膜への高効率イオン注入プロセスの研究開発

    2020.11 - 2022.3

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    Authorship:Principal investigator  Grant type:Other

    Grant amount:\120000 ( Direct Cost: \120000 )

  4. [Integrated GaN Active Matrix Emitters (i-GAME) International coauthorship

    2017.6

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    Authorship:Coinvestigator(s)  Grant type:Other

    Grant amount:\82500000 ( Direct Cost: \80097500 、 Indirect Cost:\2402500 )

Industrial property rights 3

  1. 東海国立大学機構

    鄭恵貞

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    Applicant:東海国立大学機構

    Application no:2022-069325  Date applied:2022.4

    Country of applicant:Domestic   Country of acquisition:Domestic

  2. 独立行政法人産業技術総合研究所

    福田伸子、鄭 恵貞

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    Application no:特願2013-263412(P2013-263412)  Date applied:2015.12

    Announcement no:特開2014-143403(P2014-143403A)  Date announced:2016.8

    Country of applicant:Domestic   Country of acquisition:Domestic

    【発明の名称】多成分系酸化物半導体の前駆体塗布液及び該塗布液を用いた多成分系酸化物半導体膜の製造方法

  3. 独立行政法人産業技術総合研究所

    植村 聖、鄭 恵貞

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    Applicant:独立行政法人産業技術総合研究所

    Application no:特願2015-10985(P2015-10985)  Date applied:2015.1

    Announcement no:特開2016-136565(P2016-136565A)  Date announced:2016.7

    Country of applicant:Domestic   Country of acquisition:Domestic

    【発明の名称】半導体製造装置および半導体製造方法