A. Okui, K. Moriya, N. Kai, M. Yamada, A. Nishikawa, A. Loesing, N. Ohkawa, H. Sekiguchi,“Multipoint MicroLED probes for selective neural stimulation in optogenetics,”Jpn. J. Appl. Phys. Brief Note, 64, 048005 (2025).DOI
H. Sekiguchi, H. Katagiri, K. Hoshino, R. Togashi, K. Kishino,“Voltage-tunable RGB emission from a single self-assembled InGaN nanocolumn LED,”Jpn. J. Appl. Phys. Brief Note, 64, 028004 (2025).DOI
G. Shinohara, T. Kayama, A. Okui, W. Oda, A. Nishikawa, A. Loesing, N. Kuga, T. Sasaki, H. Sekiguchi,“Hybrid Probe Combining MicroLED and Neural Electrode for Precise Neural Modulation and Multi-Site Recording,”Appl. Phys. Express, 18, 026501 (2025).DOI
2024
S. Okada, N. Ohkawa, K. Moriya, Y. Saitoh, M. Ishikawa, K. Oya, A. Nishikawa, H. Sekiguchi,“Photopharmacological modulation of hippocampal local fieldpotential by caged-glutamate with MicroLED prob,”Neuropsychopharmacol. Rep., 44, 658 (2024).DOI
R. Kanda, T. Kitade, A. Nishikawa, A. Loesing, H. Sekiguchi,“Fabrication Process of MicroLED Film for Achieving Vertical Current Injection Using Transfer Technology,”Phys. Stat. Sol. A, 221, 2400051 (2024).DOI
T. Kitade, R. Kanda, K. Matsui, A. Nishikawa, A. Loesing, I. Fukunaga, H. Sekiguchi,“Optimization of Gate Structure for Damageless MicroLED Thin Films in Optogenetic Applications,”Phys. Stat. Sol. A, 221, 2300834 (2024).DOI
2023
H. Sekiguchi,“Development of MicroLED neuroscience probe,”JSAP Rev, 2023, 230421 (2023).DOI
M. Yamaga, K. P. O’Donnell, H. Sekiguchi, A. Wakahara,“Crystal-field analysis and models of Eu-emission centers with C3v symmetry in situ Eu- and Mg-codoping GaN layers,”J. Lumin. (2023).DOI
S. Setogawa, R. Kanda, S. Tada, T. Hikima, Y. Saitoh, M. Ishikawa, S. Nakada, F. Seki, K. Hikishima, H. Matsumoto, K. Mizuseki, O. Fukayama, M. Osanai, H. Sekiguchi, N. Ohkawa,“A novel micro-ECoG recording method for recording multisensory neural activity from the parietal to temporal cortices in mice,”Molecular Brain, 16, 38 (2023).DOI
2022
H. Yasunaga, H. Takeuchi, K. Mizuguchi, A. Nishikawa, A. Loesing, M. Ishikawa, C. Kamiyoshihara, S. Setogawa, N. Ohkawa, and H. Sekiguchi,“MicroLED neural probe for effective in vivo optogenetic stimulation,”Opt. Express, 30, 40292-40305 (2022).DOI
S. Setogawa, R. Kanda, S. Tada, Y. Saitoh, M. Ishikawa, S. Nakada, F. Seki, K. Hikishima, H. Matsumoto, K. Mizuzeki, O. Fukayama, M. Osanai, H. Sekiguchi, N. Ohkawa,“A novel micro-ECoG recording method for recording multisensory neural activity from the parietal to emporal cortices in mice,”bioRxiv (2022).DOI
T. Okuno, R. Onoda, L. Toyoshima, K. Miyata, H. Sekiguchi, A. Wakahara, T. Nakaoka,“Local strain-dependent Zeeman splitting in GaN:Eu,”AIP Adv., 12, 075315 (2022).DOI
H. Sekiguchi, H. Matsuhira, R. Kanda, S. Tada, T. Kitade, M. Tsutsumi, A. Nishikawa, A. Loesing, I. Fukunaga, S. Setogawa and N. Ohkawa,“Adhesionable flexible GaN-based microLED array film to brain surface for in vivo optogenetic stimulation,”Appl. Phys. Express, 15, 046501 (2022).DOI
2021
H. Yasunaga, T. Takagi, D. Shinko, Y. Nakayama, Y. Takeuchi, A. Nishikawa, A. Loesing, M. Ohsawa, H. Sekiguchi,“Development of a neural probe integrated with high-efficiency MicroLEDs for in vivo application,”Japanese Journal of Applied Physics, 60, 016503 (2021).DOI
2020
H. Okada, K. Miwa, T. Yokoyama, K. Yamane, A. Wakahara, H. Sekiguchi,“GaN-Based Monolithic Inverter Consiting of Enhacement- and Depletion-Mode MOSFETs by Si ion,”Phys. Stat. Sol. A, 1900550 (2020).
2019
H. Sekiguchi, M. Sakai, T. Kamada, K. Yamane, H. Okada, and A. Wakahara,“Observation of single optical site of Eu and Mg codoped GaN grown by NH3-source molecular beam epitaxy,”J. Appl. Phys., 125, 175702 (2019).
H. Sekiguchi, Y. Higashi, K. Yamane, A. Wakahara, H. Okada, and K. Kishino,“Fabrication and optical properties of regularly arranged GaN-based nanocolumns on Si substrate,”J. Vac. Sci. Tech. B, 37, 31207 (2019).
H. Sekiguchi, H. Yasunaga, K. Tsuchiyama, and R. Nitta,“Neural optical probe with monolithically integrated intensity-monitoring mLED and polymer waveguide for optogenetics,”Electron. Lett., 55, 619-621 (2019).
J. A. Piedra-Lorenzana, K. Yamane, K. Shiota, J. Fujimoto, S. Tanaka, H. Sekiguchi, H. Okada, A. Wakahara,“Estimation of Ga adatom diffusion length for GaP growth by molecular beam epitaxy,”J.Cryst. Growth, 512, 37-40 (2019).
H. Sekiguchi, K. Date, T. Imanishi, H. Tateishi, K. Yamane, H. Okada, K. Kishino, A. Wakahara,“Regularly arranged Eu-doped GaN nanocolumns grown by RF-plasma-assisted molecular beam epitaxy through Ti-mask selective-area growth technique,”J. Cryst. Growth, 511, 73-78 (2019).
2018
K. Yamane, S. Mugikura, S. Tanaka, H. Sekiguchi, H. Okada, A. Wakahara,“Impact of temperature and nitrogen composition on the growth of GaAsPN alloys,”J. Cryst. Growth, 486, 24-29 (2018).
A. Sukegawa, H. Sekiguchi, R. Matsuzaki, K. Yamane, H. Okada, K. Kishino, and A. Wakahara,“Self-organized Eu doped GaN nanocolumn light-emitting diode grown by RF-molecular-beam epitaxy,”Phys. Stat. Sol. A, 216, 1800501 (2019).
2017
K. Yamane, K. Sato, H. Sekiguchi, H. Okada, A. Wakahara,“Doping control of SaAsPN alloys by molecular beam epitaxy for monolithic II-V/Si tandem solar cells,”J. Cryst. Growth, 473, 55-59 (2017).
K. Yamane, M. Goto, K. Takahashi, H. Sekiguchi, H. Okada, A. Wakahara,“Growth of a lattice-matched GaAsPN P-I-N junction on a Si substrate for monolithic III-V/Si tandem solar cells,”Appl. Phys. Express, 10, 075504 (2017).
K. Yamane, M. Moriyama, K. Boualiong, H. Sekiguchi, H. Okada, A. Wakahara,“Metal-organic vapor phase epitaxy of GaPN alloys via surface nitridation using ammonia,”Phys. Stat. Sol. (B), 254, 1600483 (2017).
H. Okada, M. Baba, M. Furukawa, K. Yamane, H. Sekiguchi, A. Wakahara,“Formation of SiO2 film by chemical capor deposition enhaced by atomic species extracted from a surface-wave generated plasma,”AIP Conference Proceedings, 1807, 020006 (2017).
H. Oktavianto, K. Yamane, H. Sekiguchi, T. Hizawa, A. Wakahara,“Hydrogen flame with bioinspired optoelectronic integrated circuit and field-programmable gate array using integrated three-dimensional system architecture,”Sens. Mater., 29, 587-600 (2017).
H. Sekiguchi, T. Imanishi, R. Matsuzaki, K. Ozaki, K. Yamane, H. Okada, K. Kishino, A. Wakahara,“Stable-wavelength operation of europium-doped GaN nanocolumn light-emitting diodes grown by rf-plasma-assisted molecular beam epitaxy,”Electron. Lett, 53, 666-668 (2017).
2016
H. Sekiguchi, M. Sakai, T. Kamada, H. Tateishi, A. Syouji and A. Wakahara,“Optical sites in Eu- and Mg-codoped GaN grown by NH3-source molecular beam epitaxy,”Appl. Phys. Lett., 109, 151106 (2016).
K. Tsuchiyama, K. Yamane, S. Utsunomiya, H. Sekiguchi, H. Okada, A. Wakahara,“Monolithic integration of Si-MOSFET and GaN-LED using Si/SiO2/GaN-LED wafer,”Appl. Phys. Express, 9, 104101 (2016).
H. Sekiguchi, S. Nishikawa, T. Imanishi, K. Ozaki, K. Yamane, H. Okada, K. Kishino, A. Wakahara,“Structural and optical properties of Eu-doped GaN nanocolumns on (111) Si substrates grown by RF-plasma-assisted molecular beam epitaxy,”Japanese Journal of Applied Physics, 55, 05FG07 (2016).
N. Urakami, K. Yamane, H. Sekiguchi, H. Okada, A. Wakahara,“Molecular-beam epitaxy growth of dilute GaAsN alloys by surface nitridation,”J. Cryst. Growth, 435, 19-23 (2016).
H. Okada, M. Shinohara, Y. Kondo, H. Sekiguchi, K. Yamane, A. Wakahara,“Investigation of HCl-based surface treatment for GaN devices,”AIP Conference Proceedings, 1709, 020011 (2016).
K. Tsuchiyama, K. Yamane, H. Sekiguchi, H. Okada, A. Wakahara,“Fabrication of Si/SiO2/GaN structure by surface-activated bonding for monolithic integration of optoelectronic devices,”Japanese Journal of Applied Physics, 55, 05FL01 (2016).
2015
Kouji Yamano, Katsumi Kishino, Hiroto Sekiguchi, Takao Oto, Akihiro Wakahara, Yoichi Kawakami,“Novel selective area growth method for regularly arranged AlGaN nanocolumns using nanotemplates,”Journal of Crystal Growth, 425, 316 (2015).
Masayoshi Kanemoto, Hiroto Sekiguchi, Keisuke Yamane, Hiroshi Okada, Akihiro Wakahara,“Eu3+ luminescence properties of Eu- and Mg-codoped AlGaN,”Journal of Luminescence, 166, 60-66 (2015).
2014
Keisuke Yamane, Noriyuki Urakami, Hiroto Sekiguchi, Akihiro Wakahara,“III-V-N compounds for multi-junction solar cells on Si,”IEEE Photovoltaic Specialist Conference, 2972 (2014).
Hiroshi Okada, Yuki Okada, Hiroto Sekiguchi, Akihiro Wakahara, Shinichiro Sato, Takeshi Ohshima,“Study of proton irradiation effects on p- and n-type GaN based on two-terminal resistance dependence on 380 keV proton fluence,”IEICE Transactions on Electronics, E97-C, 409 (2014).
2013
Manoj Kumar, Hiroto Sekiguchi, Hiroshi Okada, Akihiro Wakahara,“Influence of contact shape on AlGaN/GaN Schottky diode prepared on Si with thick buffer layer,”Applied Physics A: Materials Science and Processing, 112, 847-853 (2013).
Manoj Kumar, Changyong Lee, Hiroto Sekiguchi, Hiroshi Okada, Akihiro Wakahara,“Demonstration of a large-area AlGaN/GaN Schottky barrier photodetector on Si with high detection limit,”Semiconductor Science and Technology, 28, 94005 (2013).
Noriyuki Urakami, Hiroto Sekiguchi, Hiroshi Okada, and Akihiro Wakahara,“Growth of dilute BGaP allloys by molecular beam epitaxy,”Journal of Crystal Growth, 378, 96 (2013).
Hiroto Sekiguchi, Yasufumi Takagi, Tatsuki Otani, Ryota Matsumura, Hiroshi Okada, and Akihiro Wakahara,“Red Light-Emitting Diodes with Site Selective Eu doped GaN Active Layer,”Japanese Journal of Applied Physics, 52, 08JH01 (2013).
Hiroto Sekiguchi, Yasufumi Takagi, Tatsuki Otani, Hiroshi Okada, and Akihiro Wakahara,“Emission enhancement mechanism of GaN:Eu by Mg codoping,”Journal of Applied Physics,, 113, 13105 (2013).
Sang-Baie Shin, Hiroto Sekiguchi, Hiroshi Okada, and Akihiro Wakahara,“CMOS-Compatible Backside-Illuminated Photodiode for Opto-electronic Integrated Circuit Device,”Japanese Journal of Applied Physics, 52, 04CG12 (2013).
国際会議 (International Conferences)
2024
G. Shinohara, A. Okui, A. Nishikawa, A. Loesing, T. Kayama, N. Kuga, T. Sasaki, H. Sekiguchi,“Development of MicroLED/Neural Electrode Hybrid Device,”The 11th Asia-Pacific Workshop on Widegap Semiconductors(APWS2024), MA3-7, Hanwha Resorts Haeundae, Korea (2024).
R. Kanda, T. Kitade, A. Nishikawa, A. Loesing, H. Sekiguchi,“Development of MicroLED film with vertical current injection structure,”The 10th International Conference on Light-Emitting Devices and Their Industrial Applications (LEDIA2024), LEDIA4-05, Pacifico Yokohama, Japan (2024).
2023
Kakeru Oya, Gota Shinohara, Hibiki Takeuchi, Shogo Okada, Atsushi Nishikawa, Alexander Loesing, Mikiko Ishikawa, Nobuyuki Kai, Noriaki Ohwaka,Hiroto Sekiguchi,“Development of needle-shaped MicroLED/Microfluidic device for optogenetic stimulation and drug delivery,”The 14th International Conference on Nitride Semiconductors (ICNS-14), TuP-OD-20, Fukuoka,Japan (2023).
Ryota Kanda, Taiki Kitde, Atsushi Nishikawa, Alexander Loesing, Masaki Sirai, Hiroki Kobayashi, Izumi Fukunaga, Takuya Hikima, Noriaki Ohkawa,Hiroto Sekiguchi,“Flexible MicroLED array film adhering to the brain surface for in vivo optogenetic stimulation,”The 14th International Conference on Nitride Semiconductors (ICNS-14), OD11-4, Fukuoka,Japan (2023).
Hiroki Yasunaga, Atsushi Nishikawa, Alexander Loesing, Mikiko Ishikawa, Chikako Kamiyoshihara, Susumu Setogawa, Noriaki Ohkawa, Hiroto Sekiguchi,“Development of MicroLED neural device for effective optogenetic stimulation,”The 14th International Conference on Nitride Semiconductors (ICNS-14), OD10-7, Fukuoka,Japan (2023).
Taiki Kitade, Atsushi Nishikawa, Alexander Loesing, Masaki Shirai, Hiroki Kobayashi, Izumi Fukunaga, Hiroto Sekiguchi,“Optimization of gate structure in hollow-structured MicroLED array for batch transfer technique towards flexible LED film,”The 14th International Conference on Nitride Semiconductors (ICNS-14), OD8-3, Fukuoka,Japan (2023).
Ryota Kanda, Shuto Tada, Susumu Setogawa, Noriaki Ohkawa, Hiroto Sekiguchi,“Development of Micro-Electrocorticography Device Covering Wide Area of Cortex in Mice,”2022 MRS Spring Meeting & Exhibit, SB10.06.04, Virtual(Honolulu, Hawaii, USA.) (2022).
Hiroki Yasunaga, Daisuke Shinko, Koyo Mizuguchi, Atsushi Nishikawa, Alexander Loesing, Susumu Setogawa, Noriaki Ohkawa, Hiroto Sekiguchi,“Development of high efficiency MicroLED neural probe for in vivo optotogenetic stimulation,”The 9th International Conference on Light-Emitting Devices and Their Industrial Applications, LEDIA3-01, Kanagawa, Japan (2022).
2021
Hiroto Sekiguchi, Hiroki Yasunaga, Atsushi Nishikawa, and Masahiro Ohsawa,“Development of MicroLED Neural Probe for Optogenetics,”Materials Science and Advanced Electronics Created by Singularity, Virtual (2021).
2019
Hiroto Sekiguchi, Hiroki Yasunaga, Kazuaki Tsuchiyama, Keisuke Yamane, Hiroshi Okada, Akihiro Wakahara,“Monolithic Integration of GaN-micro-LED and Si-MOSFET for Bio-application,”The 26th International Display Workshops (IDW ’19), FMC4/LCT4-3, Sapporo, Japan (2019).
Hiroki Yasunaga, Masahiro Ohsawa, and Hiroto Sekiguchi,“Fabrication of Needle-Shaped GaN-μLED Neural Probe for Optogenetics,”The 9th Asia-Pacific Workshop on Widegap Semiconductors(APWS2019), OD4-3, Okinawa, Japan (2019).
Hiroto Sekiguchi, Masaru Sakai and Akihiro Wakahara,“Possibility of Single Optical Site of Eu and Mg Codoped GaN,”13th International Conference on Nitride Semiconductors(ICNS-13), IP02.16, Bellevue, Washington (2019).
Hiroto Sekiguchi, Kiyomasa Miwa, Keisuke Yamane, Akihiro Wakahara, and Hiroshi Okada,“GaN-based Inverter by Monolithic Integration of Threshold Controlled MOSFETs,”Compound Semiconductor Week 2019 (CSW2019) (2019).
Hiroto Sekiguchi, Hiroki Yasunaga, Keisuke Yamane, Akihiro Wakahara,“Fabrication of neural optical probe using GaN-based blue micro LEDs,”The 7th International Conference on Light-Emitting Devices and Their Industrial Applications(LEDIA’19), kanagawa, Japan (2019).
2018
Hiroki Yasunaga, Hiroto Sekiguchi,“Development of integrated blue μLED neural probes for optogenetic stimulation in the depth direction,”International Workshop on Nitride Semiconductors 2018 (2018).
A. Sukegawa, H. Sekiguchi, Y. Tamai, S. Fujiwara, K. Yamane, H. Okada, K. Kishino, A. Wakahara,“RF-MBE growth of regularly arranged Europium doped GaN nanocolumns on AlN/Si template for single photon emitter,”International Workshop on Nitride Semiconductors 2018 (2018).
Hiroto Sekiguchi, Y. Higashi, K. Yamane, H. Okada, A. Wakahara,“Effect of Column Diameter and Height on Optical Properties of Regularly Arranged GaN Nanocolumn Grown by rf-MBE,”North America Molecular Beam Epitaxy Conferecne (2018).
H. Sekiguchi, K. Yamane, H. Okada, K. Kishino, A. Wakahara,“Fabrication of regularly arranged InGaN:Eu/GaN quanutum wells by rf-plasma-assisted molecular beam epitaxy,”20th International Conference on Molecular Beam Epitxy, Th-B4-2, Renaissance (R) Shanghai Zhongshan Park Hotel (2018).
K. Yamane, Y. Tachihara, T. Kittaka, H. Sekiguchi, H. Okada, A. Wakahara,“Interpretation of lattice constant and N composition in GaPN alloys through ab initio calculations and experimentations,”International Conference on Metal Organic Vapor Phase Epitaxy-XIX (ICMOVPE-XIX), P1-30, Nara Kasugano International Forum (2018).
Hiroto Sekiguchi, Rosuke Matsuzaki, Atsushi Sukegawa, Keisuke Yamane, Hiroshi Okada, Katsumi Kishino, Akihiro Wakahara,“Eu doped GaN nanocolumn light-emitting diodes exhibiting high emission-wavelength stability,”The 45th International Symposium on coupound semiconductors, Th2B6-2, Massachusetts Institute of Technology (2018).
2017
Akihiro Wakahara, Keisuke Yamane, Kento Sato, Masaya Goto, Kenjiro Takahashi, Hiroto Sekiguchi, Hiroshi Okada,“Growth and device application of GaAsPN alloys on Si with lattice-matching conditions,”JSAP 2017 Symposium Photovoltaic 4.0, 16p-304-3, Pacifico Yokohama (2017).
Hiroto Sekiguchi, Seiya Kamizuki, Kazuaki Tsuchiyama, Keisuke Yamane, Hiroshi Okada, Akihiro Wakahara,“Si channeled Implantation in GaN in its Device Application,”9th International Symposium on Advanced Plasma Science and its Applications for Nitrides and Nanomaterials, 03aC02O, Chubu Univeristy (2017).
2016
Akihiro Wakahara, Hiroto Sekiguch, and Masaru Sakai,“Stable Luminous Eu Site with High Excitation Efficiency in NH3-MBE Grown GaN co-Doped with Mg,”The 2016 Materials Research Society Fall Meeting, EM2.9.04, Massachusetts (2016).
Keisuke Yamane, Tohoru Matsubara, Narihito Okada, Akihiro Wakahara, Kazuyuki Tadatomo,“Structural Origins of Lattice Bowing of Freestanding GaN Substrates Grown by Hydride Vapor Phase Epitaxy,”The 2016 European Materials Research Society Fall Meeting, G.6.4, Warsaw University of Technology (2016).
H. Sekiguchi, H. Tateishi, T. Imanishi, K. Yamane, H. Okada, K. Kishino, A. Wakahara,“Growth of Eu doped GaN thin film and nanocolumns grown by molecular beam epitaxy,”Energy Material Nanotechnology meeting on Epitaxy 2016, A30, Budapest, Hungary (2016).
Kento Sato, Keisuke Yamane, Masaya Goto, Kenjiroh Takahashi, Hiroto Sekiguchi, Hiroshi Okada, Akihiro Wakahara,“Doping control of GaAsPN grown by molecular beam epitaxy toward monolithic III-V/Si tandem solar cells,”The 2016 European Materials Research Society Fall Meeting, I.2.4, Warsaw, Poland (2016).
Kazuaki Tsuchiyama, Keisuke Yamane, Shu Utsunomiya, Shota Nakagawa, Yoshiki Tachihara, Hiroto Sekiguchi, Hiroshi Okada and Akihiro Wakahara,“Monolithic integration of Si-MOSFETs and GaN-?LEDs using Si/SiO2/GaN-LED structure,”The 2016 European Materials Research Society Fall Meeting, I.5.2, Warsaw, Poland (2016).
Kerlee Boualiong, Kesukei Yamane, Masashi Moriyama, Hiroto Sekiguchi, Hiroshi Okada, Akihiro Wakahara,“Metalorganic Vapor Phase Epitaxy of GaPN alloys Assisted by Surface nitridation with ammonia,”43th International Symposium on Compound Semiconductor (ISCS2016), MoP-ISCS-007, Toyama, Japan (2016).
Tomohiko Imanishi, Hiroto Sekiguchi, Satoshi Nishikawa, Kohei Ozaki, Yamane, Hiroshi Okada, Katsumi Kishino, and Akihiro Wakahara,“Eu concentration dependence of Eu doped GaN nanocolumns grown by RF-plasma-assisted molecular beam epitaxy,”43th International Symposium on Compound Semiconductor (ISCS2016), WeB1-4, Toyama, Japan (2016).
2015
Kazuaki Tsuchiyama, Keisuke Yamane, Hiroto Sekiguchi, Hiroshi Okada, and Akihiro Wakahara,“Fabrication of Si/SiO2/GaN-LED wafer using surface activated bonding,”The 6th International Symposium on Growth of III-Nitrides, We-B6, Hamamatsu, Japan (2015).
Kohei Date, Hiroto Sekiguchi, Ai Yanagihara, Keisuke Yamane, Akihiro Wakahara, Katsumi Kishino,“Evaluation of surface diffusion lengths of Ga adatom on m-and c-plane GaN during MBE growth,”The 6th International Symposium on Growth of III-Nitrides, LN-Tu-1, Hamamatsu, Japan (2015).
Satoshi Nishikawa, Hiroto Sekiguchi, Tomohiko Imanishi, Keisuke Yamane, Hiroshi Okada, Akihiro Wakahara,“Eu doped GaN nanocolumns grown by rf-plasma-assisted molecular beam eptaxy,”The 6th International Symposium on Growth of III-Nitrides, Hamamatsu, Japan (2015).
Hiroyuki Tahara, Hiroto Sekiguchi, Keisuke Yamane, Hiroshi Okada, Akihiro Wakahara,“Eu incorporation mechanism of Eu doped GaN grown by rf-plasma-assisted molecular-beam epitaxy,”The 6th International Symposium on Growth of III-Nitrides, Hamamatsu, Japan (2015).
Kento Sato, Keisuke Yamane, Shun Mugikura, Hiroto Sekiguchi, Hiroshi Okada, Akihiro Wakahara,“Effects of growth temperature on crystalline quality of high nitrogen composition GaAsPN,”The Irago Conference 2015, P53, Tahara, Japan (2015).
Yutaka Kondo, Kyohei Kawakami, Hiroshi Okada, Hiroto Sejiguchi, Keisuke Yamane, and Akihiro Wakahara,“Study of pretreatment for surface passivation layer deposition on AlGaN/GaN transistors,”11th Topical Workshop on Heterostructure Microelectronics, 9-3, Hida, Japan (2015).
Hiroto Sekiguchi, Masayoshi Kanemoto, Keisuke Yamane, Hiroshi Okada, Akihiro Wakahara,“Sharp red light-emitting diodes using optical site selected Eu doped GaN active layer,”Material Challenges in Alternative & Renewable Energy, Jeju, Korea (2015).
2014
Koji Yamano, Takao Oto, Hiroto Sekiguchi, Akihiro Wakahara, Yoichi Kawakami, Katsumi Kishino,“Regularly Arranged AlGaN Nanocolumn Growth on Nanocolumn Templates,”International Conference on Molecular Beam Epitaxy, FlagStaf, USA (2014).
Noriyuki Urakami, Hiroto Sekiguchi, Hiroshi Okada, Akihiro Wakahara,“Growth of Dilute Nitride Layer and Its Application to GaAs(P)N Quantum Well Structure,”International Conference on Molecular Beam Epitaxy, FlagStaf, USA (2014).
Hiroto Sekiguchi, Ryota Matsumura, Masayoshi Kanemoto, Takuho Kamada, Masaru Sakai, Atsushi Syouji, Akihiro Wakahara,“Optical Site Control of Eu doped GaN by Mg Codoping,”International Conference on Molecular Beam Epitaxy, FlagStaf, USA (2014).
Akihiro Wakahara, Noriyuki Urakami, Hiroto Sekiguchi, Keisuke Yamane,“III-V-N/Si heteroepitaxy for multijunction solar cells,”40th IEEE Photovoltaic Specialist Conference (PVSC-40), Denver, Colorado, USA (2014).
Akinari Takada, Satoru Ochi, Hiroto Sekiguchi, Hiroshi Okada, Akihiro Wakahara,“GaN-Based UV Sensor Array for Integration with Si Sensing Circuit,”6th International Symposium on Advanced Plasma Science and its Applications for Nitrides and Nanomaterials, Aichi, Japan (2014).
Tsuchiyama, Hiroto Sekiguchi, Hiroshi Okada, Akihiro Wakahara,“Evaluation of Optical Property in Various InGaN Micro-LED Size (l=470nm),”6th International Symposium on Advanced Plasma Science and its Applications for Nitrides and Nanomaterials, Aichi, Japan (2014).
Ryota Matsumura, Hiroto Sekiguchi, Hiroshi Okada, Akihiro Wakahara,“Eu concentration dependence of optical properties for Eu and Mg codoped GaN,”6th International Symposium on Advanced Plasma Science and its Applications for Nitrides and Nanomaterials, Aichi, Japan (2014).
2013
Akihiro Wakahara, Noriyuki Urakami, Hironari Ito, Hiroshi Okada, and Hiroto Sekiguchi,“III-N-based optoelectronic devices and their integration,”10th Topical Workshop on Heterostructure Microelectronics, Hakodate, Hokkaido, Japan (2013).
Hiroshi Okada, Yuki Okada, Hiroto Sekiguchi, Akihiro Wakahara, S. Sato, T. Oshima,“Proton irradiation effects on electrical and luminescence properties of GaN-based light emitting device,”10th Topical Workshop on Heterostructure Microelectronics, Hakodate, Hokkaido, Japan (2013).
Masayoshi Kanemoto, Hiroto Sekiguchi, Yasufumi Takagi, Hiroshi Okada, Akihiro Wakahara,“Effect of Mg codoping on optical characteristics in Eu doped AlGaN,”MRS-JSAP-Joint, Kyoto, Japan. (2013).
Hiroto Sekiguchi, Ryota Matsumura, Tatsuki Otani, Yasufumi Takagi, Hiroshi Okada, Akihiro Wakahara,“Fabrication of low-temperature-dependent light-emitting diodes using Eu and Mg codoped GaN,”International conferenece on nitride semiconductor 10, Washington, DC, USA (2013).
Noriyuki Urakami, Hironari Ito, Hiroto Sekiguchi, Hiroshi Okada, and Akihiro Wakahara,“Growth and multiple stacking of self-assembled InGaAsN/GaP quantum dot by molecular beam epitaxy,”17th Int. Conf. on Crystal Growth and Epitaxy, Warsaw, Poland (2013).
Hiroshi Okada, Yuki Okada, Hiroto Sekiguchi, Akihiro Wakahara, Shinichiro Sato, and Takeshi Ohshima,“Proton irradiation effects on p- and n-type GaN,”2013 Asia-Pacific Workshop on Fundamentals and Applications of Advanced Semiconductor Devices, Seoul, Korea (2013).
Noriyuki Urakami, Hironari Ito, Hiroto Sekiguchi, Hiroshi Okada, Akihiro Wakahara,“Growth of GaAsN quantum well structure by surface nitridation,”the 40th Int. Symp. On Compound Semiconductors, Kobe, Japan. (2013).
藤原慎二郎、関口寛人、助川睦、玉井良和、山根啓輔、岡田浩、若原昭浩、岸野克巳,“Fabrication of regularly arranged Eu-doped GaN nanocolumns on AlN/Si substrate grown by RF-MBE,”第37回電子材料シンポジウム、Th2-21、長浜ロイヤルホテル、滋賀県長浜市 (2018年1月).