The 6th International Conference on Light-Emitting Devices and Their Industrial Applications 2018(LEDIA2018)


April 25 Wed.

Joint Session (LEDIA, LDC, and IoT-SNAP)

Chairs: Atsushi Kanno(National Institute of Information and Communications Technology, Japan)
Sunao Kurimura(Natinal Institute of Material Science, Japan)
Ryuji Katayama(Osaka University, Japan)

Room 301

Start End Session No. Title Speaker Description
13:30 13:45 Opening talk Hiroshi Murata1, Kenichi Kitayama2, Ryuji Katayama1
1Osaka University, Japan,
2The Graduate School for the Creation of New Photonics Industries, Japan
13:45 14:15 IOT-LDC-LEDIA-1
Towards the Augmented Internet of Things Huei Ee Yap
LP-Research Inc., Japan
The purpose of the ARcore platform is to provide a customer with a complete system integration to create his own high-performance AR product based on the ARcore.
14:15 14:45 IOT-LDC-LEDIA-2
Fiber-optic-based Life Cycle Monitoring of Aerospace Composite Structures: Toward Digitalization of Next Generation Aircraft Shu Minakuchi, Nobuo Takeda
University of Tokyo, Japan
This talk will overview our recent activity of composite life cycle monitoring by embedded fiber-optic sensors. Detailed information obtained from composite structures can be utilized to build the digital replicas and to predict their performance.
14:45 15:15 IOT-LDC-LEDIA-3
Laser Diode Based Underwater Optical Wireless Communication Takao Sawa1, Koji Tojo2, Naoki Nishimura2, Shin Ito3
1JAMSTEC, Japan,
2Shimadzu Corp., Japan,
3SAS Co., Ltd., Japan
We developed an underwater optical wireless communication modem using high power laser diode. 20 Mbps communication speed at 120 m distance, and 32 kbps at 190 m distance were established through underwater tests.
15:15 15:45 break
15:45 16:15 IOT-LDC-LEDIA-4
Recent Progress of Retinal Imaging Laser Technology Mitsuru Sugawara
QD Laser, Japan
16:15 16:45 IOT-LDC-LEDIA-5
III-nitride Semiconductor Light Emitting Transistors Kazuhide Kumakura, Junichi Nishinaka, Hideki Yamamoto
NTT Basic Research Laboratories, NTT Corporation, Japan
Light-emitting transistors, which are based on heterojunction bipolar transistors, can output both electric and optical signals with high-frequency modulation. We discuss their potential for optical communication and optoelectronic device applications.
16:45 17:15 IOT-LDC-LEDIA-6
High Photosensitivity HFET-type Nitride Based Photosensors Motoaki Iwaya1, Tetsuya Takeuchi1, Satoshi Kamiyama1, Isamu Akasaki1, 2
1Meijo University, Japan,
2Nagoya University, Japan
In this presentation, we introduce a GaN-based heterostructure field effect transistor type photosensor featuring high photosensitivity and rejection ratio. These photosensors have many applications such as flame sensor, visible light communication etc.
April 26 Thu.

Chairs: Jeehee Cho(Chonbuk National University, Korea)
Hoi Wai Choi(The University of Hong Kong, Hong Kong)

Room 411+412

Start End Session No. Title Speaker Description
9:00 9:30 LEDIA1-1Invited Development of Advanced Hybrid GaN-based Tunnel Junction LEDs James S. Speck
University of California, Santa Barbara, USA
In this presentation, we present UCSB work on the develop of hybrid MBE/MOCVD tunnel junction LEDs. The tunnel junctions are grown directly on MOCVD LED layers which are terminated with a heavily doped layer. We review cleaning procedures prior to the NH3 (ammonia) MBE. 
9:30 9:45 LEDIA1-2 Characterization of AlGaN-Based Tunnel Junction Ultraviolet Light Emitting Diodes Yusuke Goto, Hisanori kojima, Kazuyoshi Iida, Myunghee KIM, Norikatsu Koide, Tetsuya Takeuchi, Motoaki Iwaya, Satoshi Kamiyama, Isamu Akasaki
Meijo University, Japan
We demonstrated AlGaN-based tunnel junction (TJ) ultraviolet light emitting diodes (UV-LEDs) fabricated on high-quality n-Al0.62Ga0.38N templates using MOVPE. A TJ UV LEDs emitting at 310 nm under 40mA driving current was obtained.
9:45 10:00 LEDIA1-3 Electroluminescence Enhancement for Near-Ultraviolet Light Emitting Diodes with Graphene/AZO-Based Current Spreading Layers Li Lin1, Yiyu Ou1, Xiaolong Zhu2, Berit Herstroem3, Flemming Jensen3, Haiyan Ou1
1Department of Photonics Engineering, Technical University of Denmark, Denmark,
2Department of Micro- and Nanotechnology, Technical University of Denmark, Denmark,
3DTU Danchip, Technical University of Denmark, Denmark
Near-ultraviolet light emitting diodes with different aluminum-doped zinc oxide-based current spreading layers were fabricated and electroluminescence (EL) was compared. A 170% EL enhancement was achieved by using a graphene-based interlayer.
10:00 10:15 LEDIA1-4 Optical and Device Characteristics of InGaN/GaN Light Emitting Diodes with Multilayer Graphene as Transparent and Current Spreading Electrodes Ying-Hsiang Wang1, Wei-Ming Lee1, Shih-Wei Feng1, Hsiang-Chen Wang2
1Department of Applied Physics, National University of Kaohsiung, Taiwan, Taiwan,
2Graduate Institute of Opto-Mechatronics, National Chung Cheng University, Taiwan, Taiwan
We demonstrated InGaN-based LEDs with graphene transparent conductive electrodes. The shorter response, rise, delay, and recombination times of the InGaN-based LEDs with graphene transparent conductive electrodes provide more efficient carrier injection, transport, relaxation, and recombination.
10:15 10:30 LEDIA1-5 Gan Metal–Semiconductor–Metal Ultraviolet Photodetector with a Reduced-Graphene Oxide Schottky Contact Bhishma Pandit, Jaehee Cho
Chonbuk National University, Korea
GaN and its ternary compound with AlN have drawn much attention for the high speed and high responsivity ultraviolet (UV) photodetectors (PDs) because of their direct and wide energy bandgap, robustness and high radiation hardness.
10:30 10:45 Break

LEDIAp2: Short Presentation
Chair: Hisashi Murakami(Tokyo University of Agriculture and Technology, Japan)

Start End Session No. Title Speaker Description
10:45 11:42 Short Presentation
11:42 13:00 Lunch Break

LEDIAp2: Poster Session

Exhibition Hall A

Start End Session No. Title Speaker Description
13:00 14:30 LEDIAp2-1 Algan-Based Deep UV Flip-Chip Light Emitting Diode with AlN/Al Reflector Tae Hoon Park, Tae Ho Lee, Tae Geun Kim
Korea University, Korea
AlGaN-based deep ultraviolet flip-chip light-emitting diodes using AlN/Al electrodes were studied, which shows the outstanding Ohmic behavior for both n- and p-AlGaN layers and high reflectance.
LEDIAp2-2 The Effect of the Metallic Nano-Grating for 365nm Polarized UV-LED Eun-Kyung Chu1, Nam-Woo Kang1, Beom-Rae Noh1, Hee-Jung Choi1, Kwon Yung-Ju2, Kyoung-Kook Kim1
1Dept. of Advanced Convergence Technology, Korea,
2Dept. of Nano Optical Engineering, Korea
The aluminum based metal nano-grating with a period of 100nm is fabricated on the sapphire substrate of the flip-chip by e-beam evaporator and inductively coupled plasma etching for 365nm polarized UV-LED.
LEDIAp2-3 Wide Band Gap Transparent Conductive Oxides of Oxide/Metal/Oxide Triple-Layer Structure based on Fluorine Tin Oxide Si-Won Kim1, Gyu-Jae Yohn1, Soae Jeong1, Beom-Rae Noh1, So-Yeon Park2, Suyeon Son2, Kyoung-Kook Kim1
1Convergence Technology, Korea Polytechnic University, Korea,
2Dept. of Nano Optical Engineering, Korea Polytechnic University, Korea
For wide bandgap TCOs, we fabricated OMO structure using FTO and Ag nano-layer. This TCO shows the lower resistivity of 6.43 x 10-4 Ωcm and the average optical transmittance of about 84% in deep UV
LEDIAp2-4 Efficient Blue Micro-Light-Emitting Diodes Using SiOx-Based Glass Electrode Kyung Rock Son, Byeong Ryong Lee, Tae Ho Lee, Sang Hoon Oh
School of electrical Engineering, Korea University, Korea
The SiOx-based glass electrode that has a high transmittance and even a current path was applied as a transparent conducting electrode (TCE) of micro-light-emitting diodes to overcome their saturated efficiency, instead of conventional TCE material,
LEDIAp2-5 Self-Standing ZnO Nanotube/SiO2 Core?Shell Arrays for High Photon Extraction Efficiency in III-Nitride Emitter Hee-Jung Choi1, Semi Oh2, Soo-Hyun Kang1, Kab Ha1, Eun-Kyung Chu1, Won-Seok Lee3, Soon-Hwan Kwon3, Kyoung-Kook Kim1
1Dept. of Advanced convergence Technology, Korea,
2Dept. of Materials Science & Technology (GIST), Korea,
3Dept. of Nano Optical Engineering, Korea
Self-standing ZnO nanotubes arrays were fabricated on the surface of a GaN-based emitter with an indium tin oxide (ITO) transparent layer using a hydrothermal method and temperature cooling down process.
LEDIAp2-6 Improved Light Extraction Efficiency of GaN-Based Near Ultraviolet Light-Emitting Diodes Using TiO2/HfO2 DBR Electrode with Conductive Filaments Sanghoon Oh, Kyung Rock Son, Tae Geun Kim
School of Electrical Engineering, korea university, Korea
We have reported a distributed Bragg reflector, having high reflectance, based p-type electrodes to reflect light absorbed by p-electrodes made of metal from ultraviolet micro-light emitting diodes emitting at 385 nm to improve light extraction.
LEDIAp2-7 Thermal Annealing Effect of Ti Buffer Layer for the Growth of GAN Film Tzu-Ting Lin, Shih-Hao Chan, Shao-Ze Tseng, Sheng-Hui Chen
National Central University, Taiwan
Ti buffer layers were fabricated and annealed with various temperatures to achieve good crystalline properties in (002) on Si wafer. Then GaN thin films can be deposited on the Ti buffer layer with good crystallization.
LEDIAp2-8 Characterizations and Growth of ZnO: B Films Grown by Low-Pressure Chemical Vapor Deposition on Glass Substrates Wei-Ming Lee1, Ying-Hsiang Wang1, Chin-Yi Tsai1, Shih-Wei Feng1, Chien-Hsun Chen2, Hsiang-Chen Wang3, Li-Wei Tu4
1Department of Applied Physics, National University of Kaohsiung, Kaohsiung, Taiwan, Taiwan,
2Green Energy and Environment Research Labs, Industrial Technology Research Institute, Hsinchu, Taiwan, Taiwan,
3Graduate Institute of Opto-Mechatronics, National Chung Cheng University, Taiwan, Taiwan,
4Department of Physics and Center for Nanoscience and Nanotechnology, National Sun Yat-Sen University, Kaohsiung, Taiwan, Taiwan
The results of this work provide information for the LPCVD growth of ZnO films grown on glass substrates that could be potentially utilized for high-performance and low-cost transparent conductive oxides and their associated applications.
LEDIAp2-9 A study on p-type Conductivity of Phosphorus-doped ZnO Thin Film using RF Sputtering and Annealing So-Yeon Park1, Si-Won Kim2, Gyu-Jae Yohn2, Hee-Jung Choi2, Yebin Im1, Kyoung-Kook Kim2
1Dept. of Nano Optical Engineering, Korea,
2Dept. of Advanced convergence Technology, Korea
we have tried to grow phosphorus dopes ZnO using RF sputtering and to use annealing. The p-type ZnO grown on sapphire substrate shows the electrical properties of concentration of 10^17/cm3 with mobility of 1.2 cm2/Vs.
LEDIAp2-10 Photoluminescence Investigation of Near White Light-Emitting Zinc Stannate-Based Phosphors Mu-Tsun Tsai, Chih-Chuan Chan, Chien-Hung Lin
National Formosa University, Taiwan
We experimentally investigate the near white light emission of Zn2SnO4 (ZTO)-based powders via a sol-gel process. The photoluminescence (PL) mechanism was discussed. Significant enhancement in PL intensity was demonstrated for the ZnO-rich ZTO phosphors.
LEDIAp2-11 Highly Efficient Photonic Conversion Mediums Based on Polymer  Complexes for Applications in Light Emitting Devices Petronela Horlescu, Corneliu S. Stan, Simona E. Bacaita
“Gheorghe Asachi” Technical University of Iasi/ Faculty of Chemical Engineering and Environmental Protection, Romania
New polymer complexes with impressive luminescent properties were prepared and investigated. Their facile preparation path both in bulk and thin films recommend them as photonic conversion mediums in light emitting devices.
LEDIAp2-12 Numerical and Experimental Investigations for Deposited Nanosilver Tracks on Polyimide Films with Heterostructures Chia-Yen Chan1, Kuan-Cheng Shih2, Yu-Hsin Lin1
1Instrument Technology Research Center, National Applied Research Laboratories, Taiwan,
2Kingley Rubber Industrial Co., Ltd., Taiwan
Numerical computations and experimental measurements have been complimentarily performed to study the nanosilver solution ejected from a drop-on-demand piezoelectric inkjet printhead and the characteristics of the deposited nanosilver tracks on the Polyimide substrates with heterostructures.
LEDIAp2-13 Effect of the Oxygen Concentration on Electrical Properties of GaN Crystals Grown with the Na-flux Point Seed Method K. Endo, T. Yamada, H. Kubo, K. Murakami, M. Imanishi, M. Yoshimura, Y. Mori
Osaka University, Japan
We investigated electrical properties of a GaN crystal grown with {10“1” 1} plane in the Na-flux point seed method. The resistivity was 8.9×10-4 Ω cm, which was much lower than that of crystals with (0001) plane.
LEDIAp2-14 The Effect Of Nitrogen Pressure On Threading Dislocation Density During The  Na-flux GaN Growth Using Point Seed Technique Yuki Sawada, Takumi Yamada, Kosuke Murakami, Keisuke Kakinouchi, Kosuke Nakamura, Kanako Okumura, Tomoko Kitamura, Yasuhiro Unoki, Masayuki Imanishi, Masashi Yoshimura, Yusuke Mori
Osaka University, Japan
We investigated the relationship between dislocation density and nitrogen pressure. Dislocation density reduced with reduction of nitrogen pressure, reaching the order of 104 /cm2 with 3.0-MPa pressure due to c-plane shrinking during growth.
LEDIAp2-15 Reduction of Li Impurity in the Freestanding Gan Substrate Fabricated Using the Sapphire Dissolution Technique in the Na-Flux Growth Takumi Yamada, Masayuki Imanishi, Kosuke Murakami, Kosuke Nakamura, Mamoru Imade, Masashi Yoshimura, Yusuke Mori
Osaka University, Japan
In Na-flux sapphire dissolution technique for fabricating freestanding GaN substrates, incorporation of Li impurity in crystals can’t be avoided. For reduction of Li impurity, GaN crystals were regrown on GaN substrates obtained by the technique.
LEDIAp2-16 Sol-Gel-Derived Hole-Transporting NiOx Films for Perovskite CsPbBr3 Green Light-Emitting Diodes Chun-Yuan Huang1, Shyh-Jer Huang2, Yi-Hsiu Hsieh1
1Nation Taitung University, Taiwan,
2National Cheng Kung University, Taiwan
A novel perovskite light-emitting diodes (PeLED) with nickel oxide for efficient hole transport. Via adequately adjusting the thickness of NiOx, low turn-on voltage of 3.4 V and high luminance of 1200 cd/m2 can be achieved.
LEDIAp2-17 Optically Readable GaN-based Micro-LEDs Using NiO-based ReRAM as an N-Type Contact Layer for Micro-LED Display Byeong Ryong Lee, Ju Hyun Park, Hyun Tae Kim, Kyung Rock Son, Tae Geun Kim
Korea university, Korea
New driving technology of micro-light-emitting-diodes (μLEDs) display by combining resistive random access memory (RRAM) with lateral LED have been developed. Excellent unipolar RRAM behavior and superior μLED performance were shown.
LEDIAp2-18 Optical and Device Characteristics of InGaN/GaN Light Emitting Diodes with Multilayer Graphene as Transparent and Current Spreading Electrodes Ying-Hsiang Wang1, Wei-Ming Lee1, Shih-Wei Feng1, Hsiang-Chen Wang2
1Department of Applied Physics, National University of Kaohsiung, Taiwan, Taiwan,
2Graduate Institute of Opto-Mechatronics, National Chung Cheng University, Taiwan, Taiwan
We demonstrated InGaN-based LEDs with graphene transparent conductive electrodes. The shorter response, rise, delay, and recombination times of the InGaN-based LEDs with graphene transparent conductive electrodes provide more efficient carrier injection, transport, relaxation, and recombination.
LEDIAp2-19 High Efficiency UV-Emitters with Micro-Hole Pattern and ITO Nanoparticles Beom-Rae Noh1, Joon-Sung Kwon1, Nam-Woo Kang1, Eun-Kyung Chu1, Si-Won Kim1, Kwang-Gyun Im2, Kyoung-Kook Kim1
1Dept. of Advanced Convergence Technology, Korea,
2Dept. of Nano Optical Engineering, Korea
In UV-emitter, the pitch of the micro-hole is 25 micrometers with the etching depth of 75 nm, and the diameter of micro-hole was fabricated to 4, 6, 8, and 10um by photolithography and ICP-RIE processing.

LEDIA3: Novel Application & Materials
Chairs: Ryuji Katayama(Osaka University, Japan)
Je Won Kim(Namseoul University, Korea)

Room 411+412

Start End Session No. Title Speaker Description
14:30 15:00 LEDIA3-1Invited LED Technology for Dental Applications Paul Michael Petersen
Technical University of Denmark, Denmark
LEDs have a large potential in many dental and oral applications. Areas such as photo polymerization, fluorescence imaging, photodynamic therapy, and photoactivated disinfection are important future candidates for LED based diagnostics and treatment in dentistry.
15:00 15:15 LEDIA3-2 Organosilicon-Functionalized Carbon Dots Based White LED Yunfeng Wang1, Zhengmao Yin3, Chuanjian Zhou2, Zheng Xie1, Shuyun Zhou1
1The HongKong Polytechnic University, China,
2The HongKong Polytechnic University, China,
3College of Materials Science and Engineering, Qingdao University of Science and Techlogy, China
Organisilicon functionalized carbon dots can be used as optical conversion materials in the application of dichromatic and trichromatic White LED which can meet high requirement for lighting and display.
15:15 15:30 LEDIA3-3 Solution Processed All Inorganic Quantum Dots Light Emitting Diodes with UV Ozone Treatment Hsin-Chieh Yu1, 2, Yiyang Shen2, Hoang-Tuan Vu2, Chih-Chiang Yang2, Chun-Yuan Huang3
1Institute of Lighting and Energy Photonics, College of Photonics, National Chiao Tung University, Taiwan,
2Advanced Optoelectronic Technology Center, National Cheng Kung University, Taiwan,
3Department of Applied Science, National Taitung University, Taiwan
All inorganic quantum dots light emitting diodes (QLEDs) with emission wavelength of 536nm were demonstrated. The maximum current efficiency and luminance with UV ozone treatment for 3 minutes were 1.66 cd/A and 14623 cd/m2, respectively.
15:30 15:45 LEDIA3-4 Photonic Conversion Mediums Based on Polymer Embedded Carbon Dots for Applications in Light Emitting/Solar Energy Harvesting Devices Corneliu S. Stan, Petronela Horlescu, Catalina A. Peptu
Gheorghe Asachi Technical University, Romania
The particular emissive properties of our Carbon Dots with PLQY>80% embedded in polymer matrices are suitable for applications as photonic conversion layers in light emitting devices or increasing the conversion efficiency of solar cells.
15:45 16:15 Break

LEDIA4: Advanced Devices II
Chairs: James S. Speck(UCSB, USA)
Gen-ichi Hatakoshi(Waseda University, Japan)

Room 411+412

Start End Session No. Title Speaker Description
16:15 16:45 LEDIA4-1Invited GaN Monolithic Integration for Lighting and Display Hoi Wai Choi
The University of Hong Kong, Hong Kong
The monolithic integration of optoelectronic and electronic devices on the GaN platform for lighting and display is discussed. Optoelectronic devices include red, green and blue LEDs achieved by strain manipulation, while SB-MOSFETs and BJTs are candidates as electronic devices.
16:45 17:00 LEDIA4-2 Fabrication of 10×10 array structure of micro-LED display using Si micro-cup substrate Ryosuke Nawa, Takeyoshi Onuma, Tomohiro Yamaguchi, Tohru Honda
Kogakuin Univ., Japan
Fabrication of Si micro-cup substrate and its application for a 10×10 array structure of micro-LED display are demostrated to reduction of cross-talk.
17:00 17:15 LEDIA4-3 GaAsP Tunable Single-Mode Semiconductor Laser using Periodically Slotted Structure with Simplified Fabrication Process Ryuji KatayamaSo Kusumoto, Masahiro Uemukai, 
Osaka University, Japan
A tunable single-mode laser using a 10-micron-period slotted structure was fabricated by single-step RIE for simultaneous ridge and slotted structure formation. Single-mode lasing with a 1.56 nm tuning range was demonstrated.
17:15 17:45 LEDIA4-4Invited Nano-Mold & Nano Structured LEDs Je Won Kim
Namseoul University, Korea
April 27 Fri.

LEDIA5: Characterizations
Chairs: Tetsuo Narita(Toyota Central R&D Labs. Inc., Japan)
Jong Kyu Kim(Pohang University of Sci. and Technol., Korea)

Room 411+412

Start End Session No. Title Speaker Description
9:15 9:45 LEDIA5-1Invited Nondestructive Analysis of Threading Dislocations in GaN by Multiphoton-Excitation Photoluminescence Tomoyuki Tanikawa
Institute for Materials Research, Tohoku University, Japan
Threading dislocations in GaN crystals were observed using multiphoton-excitation photoluminescence. Threading dislocations have nonradiative characteristics and they exhibited as dark lines. This method is useful for further investigation on crystal defects in widegap materials.
9:45 10:00 LEDIA5-2 Degradation of Electro-Optical Parameters and Electromigration of Hydrogen in (In)AlGaN-based UVB LEDs Johannes Glaab1, Jan Ruschel1, Tim Kolbe1, Arne Knauer1, Jens Rass1, Neysha Lobo Ploch1, Markus Weyers1, Michael Kneissl1, 2, Sven Einfeldt1
1Ferdinand-Braun-Institut, Berlin, Germany, Germany,
2Technische Universitaet Berlin, Berlin, Germany, Germany
Investigations on the degradation of UVB LEDs reveal that the change of the optical power and voltage is accompanied by electromigration of hydrogen from the p-side into the n-side of the device.
10:00 10:15 LEDIA5-3 Microstructure of GaN fin LEDs: Characterization of Structural and Optical Properties by STEM-CL Gordon Schmidt1, F. Bertram1, P. Veit1, T. Hampel1, J. Hartmann2, F. Steib2, H. Zhou2, J. Ledig2, S. Fündling2, H.-H. Wehmann2, A. Waag2, J. Cristen1
1Otto-von-Guericke-University Magdeburg, Germany,
2Technische Universität Braunschweig, Germany
Using highly spatially resolved cathodoluminescence microscopy, we present the structural and optical properties of an InGaN/GaN core-shell fin grown by metal organic vapor phase epitaxy on GaN/sapphire template covered with a patterned SiO-mask.
10:15 10:30 LEDIA5-4 Spectroscopic Ellipsometry Study on P-Type NiO Films Mizuki Ono1, Kohei Sasaki2, 3, Tomohiro Yamaguchi1, Masataka Higashiwaki3, Akito Kuramata2, Shigenobu Yamakoshi2, Tohru Honda1, Takeyoshi Onuma1, 3
1Kogakuin University, Japan,
2Tamura Corporation, Japan,
3National Institute of Information and Communications Technology, Japan
Impact of thermal annealing in N2 and O2 ambient on optical constants in p-type NiO films were studied using spectroscopic ellipsometry. O2 annealing was found to be preferred to suppress reduction of Ni vacancies.
10:30 11:00 Break

LEDIA6: Growths
Chair: Tomoyuki Tanikawa(Institute for Materials Research, Tohoku University, Japan)

Room 411+412

Start End Session No. Title Speaker Description
11:00 11:30 LEDIA6-1Invited Formation Mechanism of Singular Structure in Alinn Layer Grown on M-GaN substrate by MOVPE Yuya Inatomi1, Akira Kusaba1, Yoshihiro Kangawa1, 2, 3, Kazunobu Kojima4, Shigefusa Chichibu3, 4
1Department of Aeronautics and Astronautics, Kyushu University, Japan,
2RIAM, Kyushu University, Japan,
3IMaSS, Nagoya University, Japan,
4IMRAM, Tohoku University, Japan
We performed theoretical analysis to understand formation mechanisms of singular structures observed in AlInN epitaxial layers grown on low defect density m-plane freestanding GaN substrate by metalorganic vapor phase epitaxy (MOVPE).
11:30 11:45 LEDIA6-2 Thermodynamic and Experimental Analyses of Beta-Ga2O3 Growth by Ozone Molecular Beam Epitaxy Natsuki Ueda1, Yohei Sawada1, Keita Konishi1, Yoshiaki Nakata2, Masataka Higashiwaki2, Yoshinao Kumagai1
1Tokyo University of Agriculture and Technology, Japan,
2National Institute of Information and Communications Technology, Japan
Growth of Ga2O3 by ozone molecular beam epitaxy (MBE) was analyzed both thermodynamically and experimentally. Unique growth behavior in the experiment can be explained by thermodynamic analysis considering formation of sub-oxide molecules.
11:45 12:00 LEDIA6-3 Heteroepitaxial Growth of e-Ga2O3 Thin Films on c-Plane Sapphire and GaN templates by HVPE Mayuko Sato, Nao Takekawa, Keita Konishi, Hisashi Murakami, Yoshinao Kumagai
Tokyo University of Agriculture and Technology, Japan
Epitaxial e-Ga2O3 layers were successfully grown by hydrogen-free HVPE using GaCln and O2. It was clarified that phase-purity of e-Ga2O3 films were improved by decreasing the source zone temperature and increasing O2 input partial pressure.
12:00 13:00 Break

LEDIA7: Advanced Processes
Chair: Malgorzata Iwinska(UNIPRESS, Poland)
Tomohiro Yamaguchi(Kogakuin University, Japan)

Room 411+412

Start End Session No. Title Speaker Description
13:00 13:30 LEDIA7-1Invited High Purity in HVPE Method as an Advantage Used for Controllable Doping of GaN – Influence of Different Dopants on Electrical, Optical, and Structural Properties of GaN Crystals Malgorzata Iwinska
Institute of High Pressure Physics Polish Academy of Sciences (Unipress), Poland
Gallium nitride crystals were grown by HVPE method on high-quality GaN seeds. Different dopants were investigated in order to obtain highly conductive (Si, Ge) and semi-insulating (Mn, Fe, C) material.
13:30 13:45 LEDIA7-2 Aln Templates for Low Threading Dislocation Density GaN-on-Si: A Solution to Boost the Adoption of GaN-on-Si for LEDs and μLEDs Fabrice Semond, S. Rennesson, G. Gommé, E. Frayssinet, P. Vennéguès, J. Massies
Université Côte d’Azur, CRHEA-CNRS, France
Production of AlN-on-Si templates by MBE for MOCVD growth of low threading dislocation density GaN is presented. These templates simplify growth of GaN-on-Si and would accelerate adoption of GaN-on-Si for the fabrication LEDs and µLEDs.
13:45 14:00 LEDIA7-3 Fabrication of Polarity-Inverted GaN Heterostructure by Surface-Activated Wafer Bonding and Silicon Removal Takuya Onodera1, Masahiro Uemukai1, Kazuya Takahashi2, Motoaki Iwaya2, Isamu Akasaki2, Yusuke Hayashi3, Hideto Miyake3, Maki Kushimoto4, Heajeong Cheong5, Yoshio Honda5, Hiroshi Amano4, 5, Ryuji Katayama1
1Graduate School of Engineering, Osaka University, Japan,
2Faculty of Science and Technology, Meijo Univ., Japan,
3Graduate School of Regional Innovation Studies, Mie Univ., Japan,
4Department of Electronics, Nagoya Univ., Japan,
5DepartInstitute of Materials and Systems for Sustainability, Nagoya Univ.ment of Electronics, Nagoya Univ., Japan
We succeeded in the fabrication of polarity-inverted GaN heterostructure by utilizing layer transfer process with surface-activated bonding and subsequent removal of the silicon substrate, which is an essential structure for nonlinear optical waveguides.
14:00 14:15 LEDIA7-4 Structural Recovery of Mg-ion-Implanted N-polar Bulk GaN Substrates by High-Temperature Heat Treatment Sakiko Yamanobe1, Kento Yoshida1, Keita Konishi1, Shinya Takashima2, Masaharu Edo2, Yoshinao Kumagai1
1Tokyo University of Agriculture and Technology, Japan,
2Fuji Electric Co., Ltd., Japan
High-temperature heat treatment of N-polar bulk GaN substrates with Mg-ion-implantation on their surfaces was investigated. It was found that the structural quality can be recovered by heating at 1300 ℃ without using any capping layer.
14:15 14:30 LEDIA7-5Invited P-type Conduction of Mg-ion Implanted N-polar GaN and the Optical Investigation Tetsuo Narita1, K. Kataoka1, H. Iguchi1, K. Shima2, K. Kojima2, S.F. Chichibu2, 3, M. Kanechika1, T. Uesugi1, T. Kachi3
1Toyota Central R&D Labs., Inc., Japan,
2IMRAM, Tohoku University, Japan,
3IMaSS, Nagoya University, Japan
We demonstrate p-type conduction by using Mg and hydrogen ion implantation into nitrogen-polar GaN. The optical and electrical properties clearly exhibit the proof of p-type and the existence of point defects due to implantation.
14:30 15:15 Break

LEDIA8: Extended Wavelength Devices
Chairs: Bao-Ping Zhang(Xiamen University, China)
Young-Joo Kim(Yonsei University, Korea)

Room 411+412

Start End Session No. Title Speaker Description
15:15 15:45 LEDIA8-1Invited Arrays of Truncated Cone AlGaN Deep-Ultraviolet Light-Emitting Diodes for Efficient Outcoupling of in-Plane Emission Jong Kyu Kim
We present 280 nm AlGaN Deep-ultraviolet (DUV) light-emitting diodes (LEDs) having arrays of truncated cone (TC) shaped active mesas with MgF2/Al reflectors on the inclined sidewalls to effectively extract the intrinsically strong transverse-magnetic (TM) polarized emission.
15:45 16:00 LEDIA8-2 Design of Transverse Quasi-Phase-Matched AlN Waveguide for Deep UV Second Harmonic Generation Shuhei Yamaguchi1, Masahiro Uemukai1, Kazuya Takahashi2, Motoaki Iwaya2, Isamu Akasaki2, Yusuke Hayashi3, Hideto Miyake3, Tomoya Yamada1, Yasufumi Fujiwara1, Ryuji Katayama1
1Graduate School of Engineering, Osaka University, Japan,
2Faculty of Science and Technology, Meijo University, Japan,
3Graduate School of Regional Innovation Studies, Mie University, Japan
In order to realize high efficiency deep ultraviolet second harmonic generation, a polarity-inverted multilayer AlN-waveguide-based novel device structure, called as the transverse quasi-phase-matched structure, are proposed and designed based on the numerical simulation.
16:00 16:15 LEDIA8-3 Demonstration of Red Vertical-Microcavity LEDs with Eu-Doped GaN as an Active Layer Keishi Shiomi, Tomohiro Inaba, Jun Tatebayashi, Yasufumi Fujiwara
Osaka University, Japan
We report on the demonstration of electrically-driven red vertical-microcavity light-emitting-diodes (LEDs) with Eu-doped GaN as an active layer cladded by AlInN/GaN and dielectric ZrO2/SiO2 distributed Bragg reflectors as bottom and top microcavities, respectively.
16:15 16:45 LEDIA8-4Invited Fabrication of VCSELs Emitting in the ‘Green Gap’ Bao-Ping Zhang
Department of Electronic Engineering, Xiamen University, China
VCSELs emitting in the spectral range from 479.6 nm to 565.7 nm, covering most of the ‘green gap’, are demonstrated. These devices are featured with low threshold current, continuous-wave lasing at room temperature.

LEDIA9: Tutorial Session
Chair: Yoshinao Kumagai(Tokyo University of Agriculture and Technology, Japan)

Room 411+412

Start End Session No. Title Speaker Description
16:45 17:30 LEDIA9-1Invited Modeling and Process Design of III-nitride MOVPE Yoshihiro Kangawa1, 2, Pawel Kempisty2, 3, Kenji Shiraishi2
1Kyushu University, Japan,
2Nagoya University, Japan,
3IHPP, PAS, Poland
The knowledge of atomistic-scale phenomena on growth surface is indispensable to optimize the growth conditions of thin films. We developed a physical model for investigating unintentional doping in GaN MOVPE by an ab initio-based approach.
17:30 17:45 Closing Remarks