read0043190/published_papers/52693420 Yuusuke Takashima Kentaro Nagamatsu Masanobu Haraguchi Yoshiki Naoi Polarization-tunable plasmonic coloration across ultrawide gamut using lossy-metal/dielectric/width-modulated lossy-metal subwavelength grating structure Switchable structural coloration has attracted significant interest in many applications because this approach can dynamically generate static and multiple colors based on external stimuli. However, the dynamic controllable gamut is limited to a narrow visible region. This study experimentally demonstrated polarization-tunable plasmonic color across an ultrawide gamut using lossy-metal/dielectric/width-modulated lossy-metal subwavelength grating (SWG). The numerically simulated electromagnetic field distribution shows that p-polarized (the electric field perpendicular to the grating) and s-polarized (the field parallel to the grating) irradiations excited spectrally broadened optical resonances owing to the optical damping of the lossy metals and these resonances induced a large phase difference between both types of irradiations over a wide wavelength region. Our hypothesis that a suitable combination of different structural SWG widths can be used to design the phase difference was validated via these simulations. Moreover, the calculated field distribution showed that the designed phase difference varied the polarization states of the reflected light across the entire visible region, depending on the wavelength. The SWG structure was fabricated using electron-beam lithography, and the measured reflection spectra exhibited excellent agreement with the simulation results. The fabricated sample formed an ultrawide oval in the CIE1931 color space by rotating the polarizer and realized an extremely wide polarization-tunable gamut compared to the existing gamut. The proposed strategy, which benefits from lossy materials, contributes to development of novel design concepts and material selection for various color-control applications. AIP Publishing AIP Advances 2158-3226 15 10 null null 20251001 10.1063/5.0283117 read0043190/published_papers/52659090 Yuto Matsubara Atsushi Tomita Koki Fujii Yusuke Takayanagi Yuusuke Takashima Yoshiki Naoi Kentaro Nagamatsu High AlN molar fraction AlGaN and AlGaN/AlN superlattices growth by ultra-high-temperature metalorganic vapor phase epitaxy Abstract We demonstrated the growth of high AlN molar fraction AlGaN single-layers and AlGaN superlattices (SLs) using jet stream gas flow metalorganic vapor phase epitaxy. Successful Ga incorporation was confirmed at 1700 °C in AlGaN single-layer growth while maintaining crystalline quality, indicating coherent growth on AlN. During AlGaN/AlN SLs growth, SLs structures with sharp interfaces and a high average AlN molar fraction of 88.0% were obtained at 1500 °C. Scanning transmission electron microscopy and energy-dispersive X-ray spectroscopy revealed that the compositional distribution in the cross section of the AlGaN/AlN SLs was as expected. Furthermore, the dependence on the input Al/(Al+Ga) ratio clarified that controlling the Al flow rate led to a slight adjustment in the average AlN molar fraction, whereas controlling the Ga flow rate resulted in a substantial adjustment in the average AlN molar fraction. These findings are significant for controlling Ga incorporation during the high-temperature AlGaN growth. IOP Publishing Japanese Journal of Applied Physics 1347-4065 64 9 095503 095503 20250901 10.35848/1347-4065/adfda4 read0043190/published_papers/52659092 Yuto Matsubara Atsushi Tomita Koki Fujii Yusuke Takayanagi Yuusuke Takashima Yoshiki Naoi Kentaro Nagamatsu GaN localization in AlGaN grown by ultra-high-temperature metalorganic vapor phase epitaxy Abstract GaN localization in AlGaN was achieved through ultra-high-temperature metalorganic vapor phase epitaxy. This localization was observed as a hillock structure measuring several micrometers. Localization occurred in the nonlinear region between the input Al/(Al+Ga) ratio and solid composition (AlN in AlGaN) at 1500 °C under the condition of a high flow rate and a low Al/(Al+Ga) ratio during the simultaneous supply of Al and Ga. X-ray diffraction analysis detected a GaN peak during AlGaN growth, whereas scanning electron microscopy energy dispersive X-ray spectroscopy revealed compositional inhomogeneity of Al and Ga. These findings, which facilitate material localization, can be expected as a future technology for achieving high internal quantum efficiency. IOP Publishing Japanese Journal of Applied Physics 1347-4065 64 7 075501 075501 20250701 10.35848/1347-4065/ade415 read0043190/published_papers/47619817 Yuusuke Takashima Kentaro Nagamatsu Masanobu Haraguchi Yoshiki Naoi Dynamic wide gamut color generation using highly lossy metal-based metal-dielectric-metal structure Abstract Dynamic structural color control across a wide spectral range was experimentally achieved via phase retardation between orthogonal polarization states in a Ni/SiO₂/Ni-subwavelength grating (SWG) structure. The fabricated Ni/SiO₂/Ni-SWG structure exhibited spectrally broadened resonant reflection dips due to the optical damping of Ni. The resonances induced a large phase retardation between the p- and s-polarizations over a wide spectral range, and the retardation changed the reflected polarization states depending on the wavelength. The rotation of the analyzing polarizer enabled the dynamic variation of the reflected structural color from the sample across the wide visible color gamut. IOP Publishing Applied Physics Express 1882-0786 17 7 072005 072005 20240701 10.35848/1882-0786/ad62d3 read0043190/published_papers/46928641 Yuusuke Takashima Shunsuke Furuta Kentaro Nagamatsu Masanobu Haraguchi Yoshiki Naoi Broadband Ag/SiO₂/Fe/TiO₂ ultrathin planar absorber with a wide acceptance angle from visible to near-infrared regions We present theoretical and experimental evidences of a broadband ultrathin optical absorber, constructed using Ag(85 nm)/SiO₂(70 nm)/Fe(13 nm)/TiO₂(60 nm) planar films, with a wide acceptance angle and effective admittance similar to that of air. Calculations show that this system displays near-complete visible to near-infrared absorption owing to admittance matching. The electromagnetic distribution within the layered film reveals that the high absorption rate is primarily attributed to the deep subwavelength Fe film. Maximum absorption of 99.3% is achieved even with a 13-nm-thick Fe absorptive film, and an average absorption rate of 94.8% is observed in the 400–1100 nm wavelength range. Notably, even at 60° oblique incidence, the fabricated absorber sustains an absorption rate of 85.4% (for unpolarized light). Such absorbers can be applied to efficient thermal generation and various other applications owing to their minimal heat capacity, expansive area, and fabrication simplicity. Optica Publishing Group Optical Materials Express 2159-3930 14 3 778 778 20240226 10.1364/ome.517239 read0043190/published_papers/43601953 Kentaro Nagamatsu Takumi Miyagawa Atsushi Tomita Hideki Hirayama Yuusuke Takashima Yoshiki Naoi High growth temperature for AlN by jet stream gas flow metalorganic vapor phase epitaxy Scientific Reports 2045-2322 13 1 null null 20231200 10.1038/s41598-023-29150-6 36765074 2-s2.0-85147893388 read0043190/published_papers/43601951 Atsushi Tomita Takumi Miyagawa Hideki Hirayama Yuusuke Takashima Yoshiki Naoi Kentaro Nagamatsu Investigation of V/III ratio dependencies for optimizing AlN growth during reduced parasitic reaction in metalorganic vapor phase epitaxy Scientific Reports 2045-2322 13 1 null null 20231200 10.1038/s41598-023-30489-z 36849503 2-s2.0-85148974788 read0043190/published_papers/40133000 Kentaro Nagamatsu Shota Tsuda Takumi Miyagawa Reiya Aono Hideki Hirayama Yuusuke Takashima Yoshiki Naoi Reduction of parasitic reaction in high-temperature AlN growth by jet stream gas flow metal–organic vapor phase epitaxy Abstract AlGaN-based deep ultraviolet light-emitting diodes (LEDs) have a wide range of applications such as medical diagnostics, gas sensing, and water sterilization. Metal–organic vapor phase epitaxy (MOVPE) method is used for the growth of all-in-one structures, including doped layer and thin multilayers, using metal–organic and gas source raw materials for semiconductor devices. For AlN growth with high crystalline quality, high temperature is necessary to promote the surface migration of Al atoms and Al-free radicals. However, increase in temperature generates parasitic gas-phase prereactions such as adduct formation. In this work, AlN growth at 1500 °C by a stable vapor phase reaction has been achieved by jet stream gas flow metal–organic vapor phase epitaxy. The AlN growth rate increases with gas flow velocity and saturates at ~ 10 m/s at room temperature. Moreover, it is constant at an ammonia flow rate at a V/III ratio from 50 to 220. These results demonstrate the reduction in adduct formation, which is a typical issue with the vapor phase reaction between triethylaluminum and ammonia. The developed method provides the in-plane uniformity of AlN thickness within 5%, a low concentration of unintentionally doped impurities, smooth surface, and decrease in dislocation density because of the suppression of parasitic reactions. Springer Science and Business Media LLC Scientific Reports 2045-2322 12 1 null null 20221200 10.1038/s41598-022-10937-y read0043190/published_papers/40856452 Yuusuke Takashima Kentaro Nagamatsu Masanobu Haraguchi Yoshiki Naoi Ultra-thin deep ultraviolet perfect absorber using an Al/TiO₂/AlN system An ultra-thin perfect absorber for deep ultraviolet light was realized using an Al/TiO₂/AlN system. The TiO₂ thickness was optimized using the Fresnel phasor diagram in complex space to achieve perfect light absorption. As a result of the calculation almost perfect absorption into the TiO₂ film was found, despite the film being much thinner than the wavelength. An optimized Al/TiO₂/AlN system was fabricated, and an average absorption greater than 97% was experimentally demonstrated at wavelengths of approximately 255–280 nm at normal light incidence. Our structure does not require nanopatterning processes, and this is advantageous for low-cost and large-area manufacturing. Optica Publishing Group Optics Express 1094-4087 30 24 44229 44229 20221121 10.1364/oe.474847 read0043190/published_papers/40856442 Yuusuke Takashima Masanobu Haraguchi Yoshiki Naoi Numerical finite-difference time-domain calculation for extreme enhancement of magneto-optical effect at ultraviolet wavelength using Ni-subwavelength grating on SiO<inf>2</inf>/Ni structure Optical Review 1349-9432 29 1 62 67 20220200 10.1007/s10043-021-00711-2 2-s2.0-85122869647 read0043190/published_papers/40856444 Yuusuke Takashima Masanobu Haraguchi Yoshiki Naoi Highly reflective visible color filter based on a double layer TiO<inf>2</inf> subwavelength structure Optical Materials Express 2159-3930 11 8 2712 2721 20210801 10.1364/OME.433431 2-s2.0-85111988237 read0043190/published_papers/40856447 Yuusuke Takashima Atsuki Sasada Kentaro Nagamatsu Masanobu Haraguchi Yoshiki Naoi Design of AlN-subwavelength grating for deep ultraviolet wavelength reflector operating at 244 nm of wavelength Proceedings of SPIE - The International Society for Optical Engineering 1996-756X 11926 null null 20210000 10.1117/12.2616175 2-s2.0-85120469004 read0043190/published_papers/34436164 Kozo Sugimoto Shigeki Matsuo Yoshiki Naoi Inscribing diffraction grating inside silicon substrate using a subnanosecond laser in one photon absorption wavelength <title>Abstract</title>Using focused subnanosecond laser pulses at <inline-formula><alternatives><tex-math>$$1.064\,\upmu \hbox {m}$$</tex-math><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mn>1.064</mml:mn> <mml:mspace /> <mml:mi>μ</mml:mi> <mml:mtext>m</mml:mtext> </mml:mrow> </mml:math></alternatives></inline-formula> wavelength, modification of silicon into opaque state was induced. While silicon exhibits one-photon absorption at this wavelength, the modification was induced inside <inline-formula><alternatives><tex-math>$$300\,\upmu \hbox {m}$$</tex-math><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mn>300</mml:mn> <mml:mspace /> <mml:mi>μ</mml:mi> <mml:mtext>m</mml:mtext> </mml:mrow> </mml:math></alternatives></inline-formula>-thick silicon substrate without damaging top or bottom surfaces. The depth range of the focus position was investigated where inside of the substrate can be modified without damaging the surfaces. Using this technique, diffraction gratings were inscribed inside silicon substrate. Diffraction from the gratings were observed, and the diffraction angle well agreed with the theoretical value. These results demonstrate that this technique could be used for fabricating infrared optical elements in silicon. Springer Science and Business Media LLC Scientific Reports 2045-2322 10 1 null null 20201200 10.1038/s41598-020-78564-z read0043190/published_papers/31036547 Yuusuke Takashima Kohei Moriiwa Masanobu Haraguchi Yoshiki Naoi Optical detection for magnetic field using Ni-subwavelength grating on SiO<inf>2</inf>/thin-film Ag/glass structure Scientific Reports 2045-2322 10 1 null null 20201200 10.1038/s41598-020-74202-w 33168843 2-s2.0-85095718295 read0043190/published_papers/31036548 Yuusuke Takashima Masanobu Haraguchi Yoshiki Naoi Gan-based high-contrast grating for refractive index sensor operating blue–violet wavelength region Sensors (Switzerland) 1424-8220 20 16 1 12 20200802 10.3390/s20164444 32784872 2-s2.0-85089346041 read0043190/published_papers/31036549 Y. Okano Y. Takashima M. Haraguchi Y. Naoi Magnetically tunable visible reflectivity utilizing the electron accumulation in indium-tin-oxide waveguide layer with subwavelength grating Proceedings of SPIE - The International Society for Optical Engineering 1996-756X 11467 null null 20200000 10.1117/12.2568382 2-s2.0-85091964007 read0043190/published_papers/31036550 Yuusuke Takashima Masanobu Haraguchi Yoshiki Naoi Dual-wavelengths filter operating at visible wavelength region using subwavelength grating on waveguide structure Optical Review 1349-9432 26 5 466 471 20191001 10.1007/s10043-019-00541-3 2-s2.0-85071584691 read0043190/published_papers/31036551 Yuusuke Takashima Keita Kusaba Masanobu Haraguchi Yoshiki Naoi Highly Sensitive Refractive Index Sensor Using Dual Resonance in Subwavelength Grating/Waveguide With Normally Incident Optical Geometry IEEE Sensors Journal 1558-1748 19 15 6147 6153 20190801 10.1109/JSEN.2019.2910585 2-s2.0-85068696171 read0043190/published_papers/31036553 Yuusuke Takashima Kouhei Moriiwa Masanobu Haraguchi Yoshiki Naoi Ni subwavelength grating/SiO<inf>2</inf>/Ag based optical magnetic field sensor with normal incident geometry Proceedings of SPIE - The International Society for Optical Engineering 1996-756X 11089 null null 20190000 10.1117/12.2529017 2-s2.0-85072916851 read0043190/published_papers/31036552 Yuusuke Takashima Masanobu Haraguchi Yoshiki Naoi Optical magnetic field sensor based on guided-mode resonance with Ni subwavelength grating/waveguide structure Proceedings of SPIE - The International Society for Optical Engineering 1996-756X 10928 null null 20190000 10.1117/12.2509490 2-s2.0-85066760901 read0043190/published_papers/31036554 Yuusuke Takashima Masanobu Haraguchi Yoshiki Naoi Highly sensitive magnetic field sensor with normal-incidence geometry using Ni-based bilayer subwavelength periodic structure operating in visible-wavelength region Japanese Journal of Applied Physics 1347-4065 57 8 null null 20180800 10.7567/JJAP.57.08PE01 2-s2.0-85051050190 read0043190/published_papers/31036555 Hiroki Kawakami Yoshiki Naoi Takuro Tomita Femtosecond laser-assisted thermal annealing of Ni electrode on SiC substrate AIP Advances 2158-3226 8 6 null null 20180601 10.1063/1.5036804 2-s2.0-85048129118 read0043190/published_papers/31036556 Yuusuke Takashima Masanobu Haraguchi Yoshiki Naoi High-sensitivity refractive index sensor with normal incident geometry using a subwavelength grating operating near the ultraviolet wavelength Sensors and Actuators, B: Chemical 0925-4005 255 1711 1715 20180200 10.1016/j.snb.2017.08.185 2-s2.0-85028449949 read0043190/published_papers/40856449 Yuusuke Takashima Masanobu Haraguchi Yoshiki Naoi Guided mode resonance based magnetic field sensor including Ni nano-grating Optics InfoBase Conference Papers Part F125-OPJ 2018 null null 20180000 10.1364/OPJ.2018.31aCJ5 2-s2.0-85065837176 read0043190/published_papers/31036557 Yuusuke Takashima Masato Tanabe Masanobu Haraguchi Yoshiki Naoi Ultraviolet polarizer with a Ge subwavelength grating Applied Optics 2155-3165 56 29 8224 8229 20171010 10.1364/AO.56.008224 29047687 2-s2.0-85030664260 read0043190/published_papers/31036558 Yuusuke Takashima Masato Tanabe Masanobu Haraguchi Yoshiki Naoi Theoretical investigation of polarization control in ultraviolet wavelength region using eigenmode within subwavelength grating Optical Review 1349-9432 24 1 80 86 20170201 10.1007/s10043-016-0293-8 2-s2.0-84996879650 read0043190/published_papers/31036559 Takuro Tomita Manato Deki Eizo Yanagita Yota Bando Yoshiki Naoi Takahiro Makino Takeshi Ohshima Femtosecond-laser-induced defects on silicon carbide probed by electrical conductivity Journal of Laser Micro Nanoengineering 1880-0688 12 2 72 75 20170000 10.2961/jlmn.2017.02.0004 2-s2.0-85029502848 read0043190/published_papers/31036560 Yuusuke Takashima Masato Tanabe Masanobu Haraguchi Yoshiki Naoi Highly polarized emission from a GaN-based ultraviolet light-emitting diode using a Si-subwavelength grating on a SiO<inf>2</inf> underlayer Optics Communications 0030-4018 369 38 43 20160615 10.1016/j.optcom.2016.02.027 2-s2.0-84960900398 read0043190/published_papers/31036562 Yun Jeong Choi Yoshiki Naoi Takuro Tomita Self-organization of highly ordered honeycomb buckling patterns in crystalline thin films Japanese Journal of Applied Physics 1347-4065 54 10 null null 20151001 10.7567/JJAP.54.105502 2-s2.0-84943327917 read0043190/published_papers/31036561 Yuusuke Takashima Ryo Shimizu Masanobu Haraguchi Yoshiki Naoi Influence of low-contrast subwavelength grating shape on polarization characteristics of GaN-based light-emitting diode emissions Optical Engineering 1560-2303 54 6 null null 20150601 10.1117/1.OE.54.6.067112 2-s2.0-84947460636 read0043190/published_papers/31036563 Yuusuke Takashima Ryo Shimizu Masanobu Haraguchi Yoshiki Naoi Polarized emission characteristics of uv-led with subwavelength grating Japanese Journal of Applied Physics 1347-4065 53 7 null null 20140700 10.7567/JJAP.53.072101 2-s2.0-84903574737 read0043190/published_papers/31036564 Manato Deki Tomoki Oka Shodai Takayoshi Yoshiki Naoi Takahiro Makino Takeshi Ohshima Takuro Tomita Temperature dependence of electric conductivities in femtosecond laser modified areas in silicon carbide Materials Science Forum 1662-9752 778-780 661 664 20140000 10.4028/www.scientific.net/MSF.778-780.661 2-s2.0-84896091686 read0043190/published_papers/31036565 Dohyung Kim Heesub Lee Kazuya Yamazumi Yoshiki Naoi Shiro Sakai Fabrication of C-doped p-AlGaInN light-emitting diodes by the insertion of Al4C3 Japanese Journal of Applied Physics 1347-4065 52 8 PART 2 null null 20130800 10.7567/JJAP.52.08JG18 2-s2.0-84883138317 read0043190/published_papers/40856450 Yuusuke Takashima Ryo Shimizu Masanobu Haraguchi Yoshiki Naoi Optical characteristics of UV-LED with subwavelength grating Technical Digest of the 18th Microoptics Conference, MOC 2013 null null 20130000 2-s2.0-84894174889 read0043190/published_papers/31036566 Jin Ping Ao Yoshiki Naoi Yasuo Ohno Thermally stable TiN Schottky contact on AlGaN/GaN heterostructure Vacuum 0042-207X 87 150 154 20130000 10.1016/j.vacuum.2012.02.038 2-s2.0-84888998386 read0043190/published_papers/31036567 Tianya Tan Mitsuaki Tohno Masakazu Matsumoto Yoshiki Naoi Shiro Sakai Electroluminescence orientation in InGaN/GaN LED on nano-patterned sapphire by MOCVD Journal Wuhan University of Technology, Materials Science Edition 1000-2413 27 6 1137 1138 20121200 10.1007/s11595-012-0617-x 2-s2.0-84875709083 read0043190/published_papers/31036571 Jin Ping Ao Asato Suzuki Kouichi Sawada Satoko Shinkai Yoshiki Naoi Yasuo Ohno Schottky contacts of refractory metal nitrides on gallium nitride using reactive sputtering Vacuum 0042-207X 84 12 1439 1443 20100625 10.1016/j.vacuum.2009.12.006 2-s2.0-77956451399 read0043190/published_papers/31036570 Yuji Nariyuki Masakazu Matsumoto Takeshi Noda Katsushi Nishino Yoshiki Naoi Shiro Sakai Atsuyuki Fukano Satoru Tanaka Evaluation and re-growth of p-GaN on nano-patterned GaN on sapphire substrate Physica Status Solidi (C) Current Topics in Solid State Physics 1610-1642 7 7-8 2121 2123 20100000 10.1002/pssc.200983481 2-s2.0-77955790546 read0043190/published_papers/31036569 Yoshiki Naoi Masakazu Matsumoto Tianya Tan Mistuaki Tohno Shiro Sakai Atsuyuki Fukano Satoru Tanaka GaN-based light emitting diodes with periodic nano-structures on the surface fabricated by nanoimprint lithography technique Physica Status Solidi (C) Current Topics in Solid State Physics 1610-1642 7 7-8 2154 2156 20100000 10.1002/pssc.200983486 2-s2.0-77955835293 read0043190/published_papers/31036568 Jing Zhang Yoshiki Naoi Shiro Sakai Atsuyuki Fukano Satoru Tanaka GaN surface nanostructure photodetector based on back side incidence Physica Status Solidi (C) Current Topics in Solid State Physics 1610-1642 7 7-8 1804 1806 20100000 10.1002/pssc.200983506 2-s2.0-77955780519 read0043190/published_papers/31036573 R. Matsuoka T. Okimoto K. Nishino Y. Naoi S. Sakai AlGaN epitaxial lateral overgrowth on Ti-evaporated GaN/sapphire substrate Journal of Crystal Growth 0022-0248 311 10 2847 2849 20090501 10.1016/j.jcrysgro.2009.01.027 2-s2.0-65749086683 read0043190/published_papers/31036572 Jing Zhang Yoshiki Naoi Shiro Sakai Atsuyuki Fukano Satoru Tanaka Fabrication and photovoltaic measurements of surface nanostructure of AlGaInN-based photodetector Japanese Journal of Applied Physics 1347-4065 48 11 null null 20090000 10.1143/JJAP.48.111001 2-s2.0-73849112079 read0043190/published_papers/31036575 Mamiko Yamamoto Yuta Hamazaki Masashi Tsukihara Yoshiki Naoi Katsushi Nishino Shiro Sakai Growth of AlN and GaN by metalorganic chemical vapor deposition on BP synthesized by flux method Japanese Journal of Applied Physics, Part 2: Letters 1347-4065 46 12-16 null null 20070400 10.1143/JJAP.46.L323 2-s2.0-34547913075 read0043190/published_papers/31036576 M. Tsukihara K. Sumiyoshi T. Okimoto K. Kataoka S. Kawamichi K. Nishino Y. Naoi S. Sakai Effect of middle temperature intermediate layer on crystal quality of AlGaN grown on sapphire substrates by metalorganic chemical vapor deposition Journal of Crystal Growth 0022-0248 300 1 190 193 20070301 10.1016/j.jcrysgro.2006.11.011 2-s2.0-33847262914 read0043190/published_papers/31036577 Kazuhide Sumiyoshi Masashi Tsukihara Ken Kataoka Syuichi Kawamichi Takashi Okimoto Katsushi Nishino Yoshiki Naoi Shiro Sakai Al<inf>0.17</inf>Ga<inf>0.83</inf>N film using middle-temperature intermediate layer grown on (0001) sapphire substrate by metal-organic chemical vapor deposition Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers 1347-4065 46 2 491 495 20070208 10.1143/JJAP.46.491 2-s2.0-34547902912 read0043190/published_papers/31036578 Kazuhide Sumiyoshi Masashi Tsukihara Ken Kataoka Shuichi Kawamichi Tadashi Okimoto Katsushi Nishino Yoshiki Naoi Shiro Sakai Al<inf>0.17</inf>Ga<inf>0.83</inf>N film with middle temperature-intermediate layer grown on trenched sapphire substrate by MOCVD Journal of Crystal Growth 0022-0248 298 SPEC. ISS 300 304 20070100 10.1016/j.jcrysgro.2006.10.031 2-s2.0-33846436089 read0043190/published_papers/31036574 Y. Naoi K. Ikeda T. Hama K. Ono R. Choi T. Fukumoto K. Nishino S. Sakai S. M. Lee M. Koike Blue light emitting diode fabricated on a-plane GaN film over r-sapphire substrate and on a-plane bulk GaN substrate Physica Status Solidi (C) Current Topics in Solid State Physics 1862-6351 4 7 2810 2813 20070000 10.1002/pssc.200674826 2-s2.0-45749104253 read0043190/published_papers/31036579 F. W. Yan Y. Naoi M. Tsukihara S. Kawamichi T. Yadani K. Sumiyoshi S. Sakai Diffusion effect-induced InNAs films growth on GaAs (1 0 0) substrates by MOCVD Physica B: Condensed Matter 0921-4526 376-377 1 595 597 20060400 10.1016/j.physb.2005.12.150 2-s2.0-33645164598 read0043190/published_papers/31036580 Takashi Okimoto Masashi Tsukihara Kazuhide Sumiyoshi Ken Kataoka Katsushi Nishino Yoshiki Naoi Shiro Sakai Effect of GaNP buffer layer on AlGaN epilayers deposited on (0001) sapphire substrates by metalorganic chemical vapor deposition Japanese Journal of Applied Physics, Part 2: Letters 1347-4065 45 8-11 null null 20060310 10.1143/JJAP.45.L236 2-s2.0-33645964650 read0043190/published_papers/31036583 Fawang Yan Yoshiki Naoi Masashi Tsukihara Takayuki Yadani Shiro Sakai Interdiffusion induced In(Ga)NAs films growth on GaAs substrates by low-pressure metalorganic chemical vapor deposition Journal of Crystal Growth 0022-0248 282 1-2 29 35 20050815 10.1016/j.jcrysgro.2005.04.083 2-s2.0-22644435507 read0043190/published_papers/31036582 Y. Naoi H. Sato H. Yamamoto K. Ono A. Nakamura MKimura S. Nouda S. Sakai Growth and fabrication of AlGaInN-based UV-LEDs using SiN nano-mask technique Proceedings of SPIE - The International Society for Optical Engineering 0277-786X 5722 417 424 20050000 10.1117/12.601958 2-s2.0-23744446756 read0043190/published_papers/31036581 R. J. Choi S. Kubo M. Tsukihara K. Inoue Y. Naoi K. Nishino S. Sakai Effects of V/III flux ratio on AlInGaN/AlGaN quantum wells grown by atmospheric pressure MOCVD Physica Status Solidi C: Conferences 1610-1634 2 7 2149 2152 20050000 10.1002/pssc.200461442 2-s2.0-27344459458 read0043190/published_papers/31036584 Fawang Yan Masashi Tsukihara Akihiro Nakamura Takayuki Yadani Tetsuya Fukumoto Yoshiki Naoi Shiro Sakai Surface smoothing mechanism of AlN film by initially alternating supply of ammonia Japanese Journal of Applied Physics, Part 2: Letters 0021-4922 43 8 B null null 20040815 10.1143/JJAP.43.L1057 2-s2.0-6344231723 read0043190/published_papers/31036585 H. D. Li M. Tsukihara Y. Naoi Y. B. Lee S. Sakai Investigations of V-shaped defects and photoluminescence of thin GaN-rich GaNP layers grown on a GaN epilayer by metalorganic chemical vapor deposition Applied Physics Letters 0003-6951 84 11 1886 1888 20040315 10.1063/1.1687462 2-s2.0-1842788582 read0043190/published_papers/31036590 Young Bae Lee Ryohei Takaki Hisao Sato Yoshiki Naoi Shiro Sakai High efficiency GaN-based LEDs using plasma selective treatment of p-GaN surface Physica Status Solidi (A) Applied Research 0031-8965 200 1 87 90 20031100 10.1002/pssa.200303253 2-s2.0-0348146365 read0043190/published_papers/31036595 Jin Ping Ao Daigo Kikuta Naotaka Kubota Yoshiki Naoi Yasuo Ohno High-Temperature Stability of Copper-Gate AlGaN/GaN High Electron Mobility Transistors IEICE Transactions on Electronics 0916-8524 E86-C 10 2051 2057 20031000 2-s2.0-0242664193 read0043190/published_papers/31036591 Jin Ping Ao Daigo Kikuta Naotaka Kubota Yoshiki Naoi Yasuo Ohno Copper gate AlGaN/GaN HEMT with low gate leakage current IEEE Electron Device Letters 0741-3106 24 8 500 503 20030800 10.1109/LED.2003.815158 2-s2.0-0042387929 read0043190/published_papers/31036594 Masashi Tsukihara Yoshiki Nao Hongdong Li Shiro Sakai Dislocation reduction in GaN layer by introducing GaN-rich GaNP intermediate layers Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers 0021-4922 42 4 A 1514 1516 20030400 10.1143/jjap.42.1514 2-s2.0-0038269280 read0043190/published_papers/31036592 Hiroyuki Naoi Denis M. Shaw Yoshiki Naoi Shiro Sakai George J. Collins Growth of InAs on GaAs(1 0 0) by low-pressure metalorganic chemical vapor deposition employing in situ generated arsine radicals Journal of Crystal Growth 0022-0248 250 3-4 290 297 20030400 10.1016/S0022-0248(02)02352-7 2-s2.0-0037399976 read0043190/published_papers/31036593 M. Tsukihara Y. Naoi S. Sakai H. D. Li GaN growth using a low-temperature GaNP buffer on sapphire by metalorganic chemical vapor deposition Applied Physics Letters 0003-6951 82 6 919 921 20030210 10.1063/1.1544061 2-s2.0-0037428797 read0043190/published_papers/31036589 Yoshiki Naoi Toshihiko Tada Hongdong Li Nan Jiang Shiro Sakai Growth and evaluation of GaN with SiN interlayer by MOCVD Physica Status Solidi C: Conferences 1610-1634 7 2077 2081 20030000 10.1002/pssc.200303442 2-s2.0-34248506986 read0043190/published_papers/31036588 Jin Ping Ao Naotaka Kubota Daigo Kikuta Yoshiki Naoi Yasuo Ohno Thermal stability investigation of copper-gate AlGaN/GaN high electron mobility transistors Physica Status Solidi C: Conferences 1610-1634 7 2376 2379 20030000 10.1002/pssc.200303350 2-s2.0-77954612114 read0043190/published_papers/31036587 Masashi Tsukihara Yoshiki Naoi Hong Dong Li Tomoya Sugahara Shiro Sakai The influence of a low temperature GaNP buffer on GaN growth by metalorganic chemical vapor deposition Physica Status Solidi C: Conferences 1610-1634 7 2757 2760 20030000 10.1002/pssc.200303550 2-s2.0-84875084948 read0043190/published_papers/31036596 Hongdong Li Masashi Tsukihara Yoshiki Naoi Shiro Sakai Dislocation reduction in GaN epilayers grown on a GaNP buffer on sapphire substrate by metalorganic chemical vapor deposition Japanese Journal of Applied Physics, Part 2: Letters 0021-4922 41 11 B null null 20021115 10.1143/jjap.41.l1332 2-s2.0-20244365150 read0043190/published_papers/31036600 Jie Bai Tao Wang Yuhuai Liu Yoshiki Naoi Hongdong Li Shiro Sakai Influence of pyramidal defects on photoluminescence of Mg-doped AlGaN/GaN superlattice structures Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers 0021-4922 41 10 5909 5911 20021000 10.1143/jjap.41.5909 2-s2.0-0036818474 read0043190/published_papers/31036597 Young Bae Lee Tao Wang Yu Huai Liu Jin Ping Ao Hong Dong Li Hisao Sato Katsushi Nishino Yoshiki Naoi Shiro Sakai Fabrication of high-output-power AlGaN/GaN-based UV-light-emitting diode using a Ga droplet layer Japanese Journal of Applied Physics, Part 2: Letters 0021-4922 41 10 A null null 20021001 10.1143/jjap.41.l1037 2-s2.0-0036814774 read0043190/published_papers/31036601 Young Bae Lee Tao Wang Yu Huai Liu Jin Ping Ao Yuji Izumi Yves Lacroix Hong Dong Li Jie Bai Yoshiki Naoi Shiro Sakai High-performance 348 nm AlGaN/GaN-based ultraviolet-light-emitting diode with a SiN buffer layer Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers 0021-4922 41 7 A 4450 4453 20020700 10.1143/jjap.41.4450 2-s2.0-0036656323 read0043190/published_papers/31036598 H. Yamamoto Y. Naoi Y. Fujii Y. Shintani Lateral overgrowth of diamond films on metal masked substrate by microwave plasma chemical vapor deposition International Journal of Modern Physics B 0217-9792 16 6-7 841 844 20020320 10.1142/s0217979202010488 2-s2.0-0037139106 read0043190/published_papers/31036599 Hirofumi Yamamoto Yoshiki Naoi Yoshihiro Shintani Growth of diamond films on grooved Si substrates Journal of Crystal Growth 0022-0248 236 1-3 176 180 20020300 10.1016/S0022-0248(01)01912-1 2-s2.0-0036498924 read0043190/published_papers/31036602 Y. Naoi Y. Kawakami T. Nakanishi Y. Lacroix Y. Shintani S. Sakai Characterization of GaN films etched using reactive ion etching technique by secondary ion mass spectrometry Materials Science in Semiconductor Processing 1369-8001 4 6 555 558 20011200 10.1016/S1369-8001(02)00016-1 2-s2.0-0035574893 read0043190/published_papers/31036603 A. P. Young L. J. Brillson Y. Naoi C. W. Tu Chemical composition, morphology, and deep level electronic states of GaN (0001) (1×1) surfaces prepared by indium decapping Journal of Vacuum Science and Technology B: Microelectronics and Nanometer Structures 1071-1023 19 6 2063 2066 20011100 10.1116/1.1412656 2-s2.0-0035519465 read0043190/published_papers/31036604 H. Naoi D. M. Shaw Y. Naoi G. J. Collins S. Sakai Growth of InNAs by low-pressure metalorganic chemical vapor deposition employing microwave-cracked nitrogen and in situ generated arsine radicals Journal of Crystal Growth 0022-0248 222 3 511 517 20010100 10.1016/S0022-0248(00)00975-1 2-s2.0-0035152091 read0043190/published_papers/31036607 S. Sakai T. Wang Y. Morishima Y. Naoi New method of reducing dislocation density in GaN layer grown on sapphire substrate by MOVPE Journal of Crystal Growth 0022-0248 221 1-4 334 337 20001200 10.1016/S0022-0248(00)00709-0 2-s2.0-0034511241 read0043190/published_papers/31036609 Nan Jiang Susumu Kujime Hirofumi Yamamoto Takeshi Inaoka Yoshiki Naoi Yoshihiro Shintani Hiroshi Makita Akimitsu Hatta Akio Hiraki Electron microscopic study on the initial stages of (111)-oriented diamonds grown on Pt substrates Japanese Journal of Applied Physics, Part 2: Letters 0021-4922 39 6 B null null 20000600 10.1143/jjap.39.l623 2-s2.0-0034205915 read0043190/published_papers/31036605 L. J. Brillson A. P. Young T. M. Levin G. H. Jessen J. Schäfer Y. Yang S. H. Xu H. Cruguel G. J. Lapeyre F. A. Ponce Y. Naoi C. Tu J. D. McKenzie C. R. Abernathy Localized states at GaN surfaces, Schottky barriers, and quantum well interfaces Materials Science and Engineering B: Solid-State Materials for Advanced Technology 0921-5107 75 2-3 218 223 20000601 10.1016/S0921-5107(00)00367-6 2-s2.0-33645803654 read0043190/published_papers/31036608 Alexander P. Young Leonard J. Brillson Yoshiki Naoi Charles W. Tu Effect of nitrogen ion damage on the optical and electrical properties of MBE GaN grown on MOCVD GaN/sapphire templates Materials Research Society Symposium - Proceedings 0272-9172 595 null null 20000000 2-s2.0-0033701731 read0043190/published_papers/31036606 Alexander P. Young Leonard J. Brillson Yoshiki Naoi Charles W. Tu The effect of nitrogen ion damage on the optical and electrical properties of MBE GaN grown on MOCVD GaN/sapphire templates MRS Internet Journal of Nitride Semiconductor Research 1092-5783 5 SUPPL. 1 null null 20000000 10.1557/s1092578300005081 2-s2.0-3242785635 read0043190/published_papers/31036610 L. J. Brillson T. M. Levin G. H. Jessen A. P. Young C. Tu Y. Naoi F. A. Ponce Y. Yang G. J. Lapeyre J. D. MacKenzie C. R. Abernathy Defect formation near GaN surfaces and interfaces Physica B: Condensed Matter 0921-4526 273-274 70 74 19991215 10.1016/S0921-4526(99)00409-3 2-s2.0-0033314702 read0043190/published_papers/31036615 S. Mahanty M. Hao T. Sugahara R. S.Q. Fareed Y. Morishima Y. Naoi T. Wang S. Sakai V-shaped defects in InGaN/GaN multiquantum wells Materials Letters 0167-577X 41 2 67 71 19991000 10.1016/S0167-577X(99)00105-6 2-s2.0-0033364030 read0043190/published_papers/31036611 T. Tsuruoka M. Kawasaki S. Ushioda R. Franchy Y. Naoi T. Sugahara S. Sakai Y. Shintani Combined HREELS/LEED study on the oxidation of GaN surfaces Surface Science 0039-6028 427-428 257 261 19990601 10.1016/S0039-6028(99)00275-7 2-s2.0-0033149491 read0043190/published_papers/31036612 M. Hao S. Mahanty T. Sugahara Y. Morishima H. Takenaka J. Wang S. Tottori K. Nishino Y. Naoi S. Sakai Configuration of dislocations in lateral overgrowth GaN films Journal of Applied Physics 0021-8979 85 9 6497 6501 19990501 10.1063/1.370110 2-s2.0-13044313490 read0043190/published_papers/31036613 J. Wang M. Nozaki M. Lachab R. S. Qhalid Fareed Y. Ishikawa T. Wang Y. Naoi S. Sakai Formation and optical properties of InGaN/GaN nano-structures grown on amorphous Si substrates by MOCVD Journal of Crystal Growth 0022-0248 200 1-2 85 89 19990400 10.1016/S0022-0248(98)00935-X 2-s2.0-0033115624 read0043190/published_papers/31036616 J. Wang M. Nozaki Y. Ishikawa M. S. Hao Y. Morishima T. Wang Y. Naoi S. Sakai Fabrication of nanoscale structures of InGaN by MOCVD lateral overgrowth Journal of Crystal Growth 0022-0248 197 1-2 48 53 19990000 10.1016/S0022-0248(98)00777-5 2-s2.0-0033080109 read0043190/published_papers/31036614 Doo Hyeb Youn Mohamed Lachab Maosheng Hao Tomoya Sugahara Hironori Takenaka Yoshiki Naoi Shiro Sakai Investigation on the P-ype activation mechanism in Mg-doped GaN films grown by metalorganic chemical vapor deposition Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers 0021-4922 38 2 A 631 634 19990000 10.1143/jjap.38.631 2-s2.0-0347270586 read0043190/published_papers/31036619 Tomoya Sugahara Maosheng Hao Tao Wang Daisuke Nakagawa Yoshiki Naoi Katsusi Nishino Shiro Sakai Role of dislocation in InGaN phase Separation Japanese Journal of Applied Physics, Part 2: Letters 0021-4922 37 10 SUPPL. B null null 19981015 10.1143/jjap.37.l1195 2-s2.0-0032181735 read0043190/published_papers/31036625 Doo Hyeb Youn Maosheng Hao Yoshiki Naoi Sourindra Mahanty Shiro Sakai Comparison and investigation of ohmic characteristics in the Ni/AuZn and Cr/AuZn metal schemes Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers 0021-4922 37 9 A 4667 4671 19980900 10.1143/jjap.37.4667 2-s2.0-0032154560 read0043190/published_papers/31036622 Y. Naoi K. Kobatake S. Kurai K. Nishino H. Sato M. Nozaki S. Sakai Y. Shintani Characterization of bulk GaN grown by sublimation technique Journal of Crystal Growth 0022-0248 189-190 163 166 19980615 10.1016/S0022-0248(98)00218-8 2-s2.0-0032089894 read0043190/published_papers/31036621 T. Tsuruoka N. Takahashi R. Franchy S. Ushioda Y. Naoi H. Sato S. Sakai Y. Shintani HREELS analysis of the vibrational and electronic properties of GaN film on sapphire(0 0 0 1) grown by metalorganic chemical vapor deposition Journal of Crystal Growth 0022-0248 189-190 677 681 19980615 10.1016/S0022-0248(98)00248-6 2-s2.0-0348200628 read0043190/published_papers/31036620 Shiro Sakai Tin S. Cheng Thomas C. Foxon Tomoya Sugahara Yoshiki Naoi Hiroyuki Naoi Growth of InNAs on GaAs(1 0 0) substrates by molecular-beam epitaxy Journal of Crystal Growth 0022-0248 189-190 471 475 19980615 10.1016/S0022-0248(98)00333-9 2-s2.0-0032092033 read0043190/published_papers/31036626 Doo Hyeb Youn Maosheng Hao Hisao Sato Tomoya Sugahara Yoshiki Naoi Shiro Sakai Ohmic contact to p-type GaN Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers 0021-4922 37 4 SUPPL. A 1768 1771 19980400 10.1143/jjap.37.1768 2-s2.0-0032050593 read0043190/published_papers/31036624 Hisao Sato Tomoya Sugahara Yoshiki Naoi Shiro Sakai Compositional inhomogeneity of InGaN grown on sapphire and bulk GaN substrates by metalorganic chemical vapor deposition Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers 0021-4922 37 4 SUPPL. A 2013 2015 19980400 10.1143/jjap.37.2013 2-s2.0-0032047588 read0043190/published_papers/31036623 Tomoya Sugahara Hisao Sato Maosheng Hao Yoshiki Naoi Satoshi Kurai Satoru Tottori Kenji Yamashita Katsushi Nishino Linda T. Romano Shiro Sakai Direct evidence that dislocations are non-radiative recombination centers in GaN Japanese Journal of Applied Physics 1347-4065 37 4A L398 L400 19980400 10.1143/jjap.37.l398 2-s2.0-85042807979 read0043190/published_papers/31036627 Maosheng Hao Tomoya Sugahara Hisao Sato Yoshiyuki Morishima Yoshiki Naoi Linda T. Romano Shiro Sakai Study of threading dislocations in wurtzite GaN films grown on sapphire by metalorganic chemical vapor deposition Japanese Journal of Applied Physics, Part 2: Letters 0021-4922 37 3 A null null 19980300 10.1143/jjap.37.l291 2-s2.0-0032023301 read0043190/published_papers/31036628 Hisao Sato Tomoya Sugahara Maosheng Hao Yoshiki Naoi Satoshi Kurai Kenji Yamashita Katsushi Nishino Shiro Sakai Surface pretreatment of bulk GaN for homoepitaxial growth by metalorganic chemical vapor deposition Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers 0021-4922 37 2 626 631 19980200 10.1143/jjap.37.626 2-s2.0-0031998287 read0043190/published_papers/31036629 S. Sakai H. Sato T. Sugahara Y. Naoi S. Kurai K. Yamashita S. Tottori M. Hao K. Wada K. Nishino Growth of bulk GaN by sublimation method Materials Science Forum 1662-9752 264-268 PART 2 1107 1110 19980000 10.4028/www.scientific.net/msf.264-268.1107 2-s2.0-0342457407 read0043190/published_papers/31036618 Maosheng Hao Tomoya Sugahara Satoru Tottori Masaaki Nozaki Satoshi Kurai Katsushi Nishino Yoshiki Naoi Shiro Sakai Correlation between dislocations and luminescence in GaN Proceedings of SPIE - The International Society for Optical Engineering 0277-786X 3419 138 145 19980000 10.1117/12.311002 2-s2.0-0032401561 read0043190/published_papers/31036617 Hiroki Uemura Hirofumi Yamamoto Takeshi Inaoka Hiroshi Makita Yoshiki Naoi Yoshihiro Shintani Temperature dependence of crystal size and nucleation density of diamond film New Diamond and Frontier Carbon Technology 1344-9931 8 5 339 346 19980000 2-s2.0-3042956674 read0043190/published_papers/31036631 Hisao Sato Yoshiki Naoi Shiro Sakai X-ray diffraction analysis of GaN and GaN/InGaN/GaN double-hetero structures grown on sapphire substrate by metalorganic chemical vapor deposition Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers 0021-4922 36 4 A 2018 2021 19970400 10.1143/jjap.36.2018 2-s2.0-0031120414 read0043190/published_papers/31036634 Hisao Sato Mihir Ranjan Sarkar Yoshiki Naoi Shiro Sakai XPS measurement of valence band discontinuity at GaP/GaN heterointerfaces Solid-State Electronics 0038-1101 41 2 SPEC. ISS. 205 207 19970200 10.1016/s0038-1101(96)00167-0 2-s2.0-0031076048 read0043190/published_papers/31036632 Hiroyuki Naoi Yoshiki Naoi Shiro Sakai MOCVD growth of InAsN for infrared applications Solid-State Electronics 0038-1101 41 2 SPEC. ISS. 319 321 19970200 10.1016/s0038-1101(96)00236-5 2-s2.0-0031078861 read0043190/published_papers/31036635 S. Sakai S. Kurai K. Nishino K. Wada H. Sato Y. Naoi Growth of GaN by sublimation technique and homoepitaxial growth by MOCVD Materials Research Society Symposium - Proceedings 0272-9172 449 15 22 19970000 2-s2.0-0030685023 read0043190/published_papers/31036633 H. Sato Y. Naoi S. Sakai Structural analysis of GaN and GaN/InGaN/GaN DH structures on sapphire (0001) substrate grown by MOCVD Materials Research Society Symposium - Proceedings 0272-9172 449 441 446 19970000 2-s2.0-0030711985 read0043190/published_papers/31036630 Hiroki Uemura Akira Mizoguchi Takahiro Hanabusa Kazutaka Takeda Takeshi Inaoka Hiroshi Makita Yoshiki Naoi Yoshihiro Shintani Takeshi Tachibana Growth conditions of highly oriented diamond on Pt substrate New Diamond and Frontier Carbon Technology 1344-9931 7 5-6 293 296 19970000 2-s2.0-3042909216 read0043190/published_papers/31036636 Tatsuya Okada Satoshi Kurai Yoshiki Naoi Katsushi Nishino Fukuji Inoko Shiro Sakai Transmission electron microscopy of sublimation-grown GaN single crystal and GaN homoepitaxial film Japanese Journal of Applied Physics, Part 2: Letters 0021-4922 35 10 SUPPL. B null null 19961015 10.1143/jjap.35.l1318 2-s2.0-0030259931 read0043190/published_papers/31036637 Satoshi Kurai Toshimitsu Abe Yoshiki Naoi Shiro Sakai Growth and characterization of thick GaN by sublimation method and homoepitaxial growth by metalorganic chemical vapor deposition Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers 0021-4922 35 3 1637 1640 19960300 10.1143/jjap.35.1637 2-s2.0-0030100471 read0043190/published_papers/31036638 Satoshi Kurai Yoshiki Naoi Toshimitsu Abe Susumu Ohmi Shiro Sakai Photopumped stimulated emission from homoepitaxial GaN grown on bulk GaN prepared by sublimation method Japanese Journal of Applied Physics, Part 2: Letters 0021-4922 35 1 B null null 19960100 10.1143/jjap.35.l77 2-s2.0-0029753163 read0043190/published_papers/31036639 Yoshiki Naoi Satoshi Kurai Shiro Sakai Tao Yang Hoshihiro Shintani Stress distribution and dislocation dynamics in GaAs grown on Si by metalorganic chemical vapor deposition Journal of Crystal Growth 0022-0248 145 1-4 321 325 19941202 10.1016/0022-0248(94)91070-7 2-s2.0-0028761905 read0043190/published_papers/31036640 Y. Naoi K. Ito Y. Uehara S. Ushioda Y. Murata Very high resolution photoelectron spectra of NEA-GaAs Surface Science 0039-6028 283 1-3 457 461 19930301 10.1016/0039-6028(93)91019-L 2-s2.0-0027553444 read0043190/published_papers/31036641 Yuji Hirao Yoshiki Naoi Yoshinobu Nagano Masuo Fukui Light Emission Characteristics and Surface Roughness of Au/AlO<inf>x</inf>/Al Tunnel Junction Journal of the Physical Society of Japan 1347-4073 60 12 4366 4373 19911200 10.1143/JPSJ.60.4366 2-s2.0-0004421066 read0043190/published_papers/31036642 Y. Naoi M. Fukui Intensity of surface-plasmon polariton energy emitted into the air side in an air/Ag-film/prism configuration Physical Review B 0163-1829 42 8 5009 5012 19900000 10.1103/PhysRevB.42.5009 2-s2.0-35949011877 read0043190/published_papers/31036643 Yoshiki Naoi Masuo Fukui Evaluation of Surface Roughness Parameters of Metal Films by Light Scattering Technique Journal of the Physical Society of Japan 1347-4073 58 12 4511 4516 19890000 10.1143/JPSJ.58.4511 2-s2.0-0004394156 read0043190/misc/35418648 TAKASHIMA Yuusuke 高島 祐介 SHIMIZU Ryo 清水 亮 HARAGUCHI Masanobu 原口 雅宣 NAOI Yoshiki 直井 美貴 Linearly polarized nitride-based light emitting diode with multilayer subwavelength grating 多層サブ波長回折格子を用いた窒化物系直線偏光LED (レーザ・量子エレクトロニクス) We investigated the polarization characteristics of UV-LED with multilayer subwavelength grating. The grating structure was optimized for polarization control by the eigen-mode analysis within the grating and the investigation of the field distribution with finite time difference domain method. The optimized structure was fabricated on GaN based UV-LED. The electroluminescence spectra from the UV-LED showed highly polarized emission. The extinction ratio reached to 11. We succeeded in demonstrating highly polarized UV-LED by using multilayer subwaveength grating. 紫外偏光制御デバイスは半導体リソグラフィーや医療等の多くの工業分野で利用される重要なデバイスである．近年，III族窒化物LEDの発展によって，集積デバイスへの応用も期待されるようになってきた．そこで我々は多層サブ波長回折格子を用いた偏光制御UV-LEDへの応用に着目した．サブ波長回折格子中では，従来の回折とは異なり，周期的な屈折率分布による固有モードと入射光の相互作用が光伝播を支配する．そのモード固有状態を制御することにより低損失かつ高い偏光選択性が期待できる．今回，多層サブ波長回折格子がUV-LEDの偏光特性に与える影響の理論的検討を行い最適構造をUV-LED上に作製した結果，消光比11:1の偏光特性を有するUV-LEDを実現した． The Institute of Electronics, Information and Communication Engineers 一般社団法人電子情報通信学会 Technical report of IEICE. LQE 電子情報通信学会技術研究報告 = IEICE technical report : 信学技報 0913-5685 114 338 69 72 20141127 read0043190/misc/35231630 SUGAHARA T. 菅原 智也 FAREED R.S.Q. 直井 美貴 WANG T. 西野 克志 NAOI Y. 直井 美貴 NISHINO K. 西野 克志 SAKAI S. 酒井 士郎 Cathodoluminescence Characterization of Dislocation Property in Nitride Semiconductors CL法による窒化物半導体の転位特性の評価 日本電子顕微鏡学会 Electron-microscopy 電子顕微鏡 0417-0326 34 225 228 19991101 read0043190/misc/38364320 Matsui Y. 松井 之輝 Tsuruoka T. 鶴岡 徹 Ushioda S. 潮田 資勝 Naoi Y. 直井 美貴 Naoi H. 直井 弘之 Sakai S. 酒井 士郎 Shintani Y. 新谷 義廣 Electron energy loss spectra of modulation-doped GaAs/AlGaAs single heterostructure 変調ドープGaAs/AlGaAs単一ヘテロ構造のエネルギー損失スペクトル The Physical Society of Japan (JPS) 一般社団法人日本物理学会 Abstracts of the meeting of the Physical Society of Japan. Sectional meeting 日本物理学会講演概要集. 秋の分科会 1996 2 130 130 19960913 read0043190/misc/37744286 Naoi Hiroyuki 直井 弘之 Naoi Yoshiki 直井 美貴 Sakai Shiro 酒井 士郎 Shintani Yoshihiro 新谷 義廣 Theoretical consideration about the growth mechanism of GaAs on the small groove made in Si substrate by selective MOCVD 選択MOCVD成長によるSi基板上微小溝でのGaAsの埋め込みパターンの理論的考察 Selective MOCVD growth of GaAs on preferentially etched(100)Si substrate was investigated.Si(100)substrate which was etched to different depth using SiO_2 as a etching mask were prepared,and GaAs was grown by MOCVD at about 20 torr.The growth rate on the etched Si substrate is analyzed to find out a condition to obtain flat surface after the growth.The longer migration length of the growing species and the longer bottom surface length in the grooves makes the surface flat. Si基板上微小溝へのGaAsの選択MOCVD成長を行った場合の埋め込みパターンの平坦化について議論する．KOHにより，SiO_2をマスクとして面方位(100)のSi基板にさまざまな深さの溝を作製し，GaAsの選択MOCVD成長を行った．また，表面拡散方程式を用いることにより，溝部での成長速度を計算した．その結果，原料種のマイグレーション長および溝の底面が大きいほど，埋め込みパターンが平坦化することが分かった． The Institute of Electronics, Information and Communication Engineers 一般社団法人電子情報通信学会 Technical report of IEICE. OPE 電子情報通信学会技術研究報告. OPE, 光エレクトロニクス 94 397 13 18 19941215 応用物理学会 応用物理学会2019年春季学術講演会Poster Award 20190300 財団法人三木康楽会 三木康楽会賞 20040100