Search Results - "Sumi, Tomoaki"

Vacancy-type defects in bulk GaN grown by oxide vapor phase epitaxy probed using positron annihilation by Uedono, Akira, Takino, Junichi, Sumi, Tomoaki, Okayama, Yoshio, Imanishi, Masayuki, Ishibashi, Shoji, Mori, Yusuke

“…•Vacancies in GaN grown by OVPE method were studied using positron annihilation.•Major defect species was identified as Ga-vacancy coupled with oxygen…”
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Effect of additional N2O gas on the suppression of polycrystal formation and high-rate GaN crystal growth by OVPE method by Shimizu, Ayumu, Kitamoto, Akira, Kamiyama, Masahiro, Tsuno, Shintaro, Ishibashi, Keiju, Usami, Shigeyoshi, Imanishi, Masayuki, Maruyama, Mihoko, Yoshimura, Masashi, Sumi, Tomoaki, Takino, Junichi, Okayama, Yoshio, Hata, Masahiko, Isemura, Masashi, Mori, Yusuke

“…•We introduced N2O gas into the OVPE-GaN growth process.•Polycrystal formation was suppressed by the addition of N2O gas.•The 512-µm-thick OVPE-GaN layer was…”
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Development of a 2-inch GaN wafer by using the oxide vapor phase epitaxy method by Takino, Junichi, Sumi, Tomoaki, Okayama, Yoshio, Nobuoka, Masaki, Kitamoto, Akira, Imanishi, Msayuki, Yoshimura, Masashi, Mori, Yusuke

“…From the previous studies, one of the challenges in the oxide vapor phase epitaxy (OVPE) method was suppressing poly-crystal generation for thick GaN growth…”
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Floral design GaN crystals: low-resistive and low-dislocation-density growth by oxide vapor phase epitaxy by Takino, Junichi, Sumi, Tomoaki, Okayama, Yoshio, Kitamoto, Akira, Usami, Shigeyoshi, Imanishi, Masayuki, Yoshimura, Masashi, Mori, Yusuke

“…Abstract GaN crystal growth mode in the oxide vapor phase epitaxy (OVPE) method, which simultaneously provides low electrical resistance and low threading…”
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Influence of oxygen-related defects on the electronic structure of GaN by Ohata, Satoshi, Kawamura, Takahiro, Akiyama, Toru, Usami, Shigeyoshi, Imanishi, Masayuki, Yoshimura, Masashi, Mori, Yusuke, Sumi, Tomoaki, Takino, Junichi

“…Abstract Perfect GaN is a colorless, transparent crystal. However, because of intentional and unintentional impurities, GaN crystals have colors and lose some…”
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Effect of methane additive on GaN growth using the OVPE method by Kitamoto, Akira, Takino, Junichi, Sumi, Tomoaki, Kamiyama, Masahiro, Tsuno, Shintaro, Ishibashi, Keiju, Gunji, Yoshikazu, Imanishi, Masayuki, Okayama, Yoshio, Nobuoka, Masaki, Isemura, Masashi, Yoshimura, Masashi, Mori, Yusuke

“…The oxide vapor phase epitaxy method is expected to be a useful technique for bulk GaN growth, because it allows long-term growth without producing a solid…”
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Vapor-phase epitaxial growth of GaN films using Ga2O vapor and NH3 by Imade, Mamoru, Bu, Yuan, Sumi, Tomoaki, Kitamoto, Akira, Yoshimura, Masashi, Sasaki, Takatomo, Imsemura, Masashi, Mori, Yusuke

“…High-temperature epitaxial growth (>1200°C) of GaN using Ga2O vapor and NH3 was performed to increase the crystal growth rate and improve crystal qualities…”
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Pressure-Dependent Raman Scattering Spectrum of Piezoelectric (Li,Na,K)NbO3 Lead-Free Ceramics by Kakimoto, Ken-ichi, Sumi, Tomoaki, Kagomiya, Isao

“…High-pressure Raman scattering experiments have been carried out for (Na 0.5 K 0.5 )NbO 3 and Li x (Na 0.5 K 0.5 ) 1-x NbO 3 (abbreviated as LNKN-100$x$)…”
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Dependence of polarity inversion on V/III ratio in −c-GaN growth by oxide vapor phase epitaxy by Taniyama, Yuki, Yamaguchi, Yohei, Takatsu, Hiroaki, Sumi, Tomoaki, Kitamoto, Akira, Imade, Mamoru, Yoshimura, Masashi, Isemura, Masashi, Mori, Yusuke

“…One of the issues in bulk c-GaN growth is the decrease in the diameter of crystals with an increase in thickness owing to the appearance of inclined and…”
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Growth of GaN layers using Ga2O vapor obtained from Ga and H2O vapor by Sumi, Tomoaki, Taniyama, Yuuki, Takatsu, Hiroaki, Juta, Masami, Kitamoto, Akira, Imade, Mamoru, Yoshimura, Masashi, Isemura, Masashi, Mori, Yusuke

“…In this study, we performed growth of GaN layers using Ga2O vapor synthesized from Ga and H2O vapor. In this process, we employed H2O vapor instead of HCl gas…”
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High Temperature Growth of Non-polar $a$-Plane GaN Film Grown Using Gallium-Oxide as Ga Source by Sumi, Tomoaki, Bu, Yuan, Kitamoto, Akira, Imade, Mamoru, Yoshimura, Masashi, Isemura, Masashi, Mori, Yusuke

“…In this study, we reported a decrease of oxygen concentration and an increase in the growth rate of $a$-plane gallium nitride ($a$-GaN) film grown using Ga 2 O…”
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Origin of Black Color in Heavily Doped n‐Type GaN Crystal by Sumi, Tomoaki, Takino, Junichi, Okayama, Yoshio, Usami, Shigeyoshi, Imanishi, Masayuki, Yoshimura, Masashi, Mori, Yusuke

“…In semiconductor materials, doping is used mainly for controlling the electrical properties. There have been attempts to grow low‐resistivity n‐type gallium…”
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Homoepitaxial growth of a-plane GaN layers by reaction between Ga2O vapor and NH3 gas by Sumi, Tomoaki, Taniyama, Yuuki, Takatsu, Hiroaki, Juta, Masami, Kitamoto, Akira, Imade, Mamoru, Yoshimura, Masashi, Isemura, Masashi, Mori, Yusuke

“…Growth of high-quality a-plane GaN layers was performed by reaction between Ga2O vapor and NH3 gas at a high temperature. Smooth a-plane GaN epitaxial layers…”
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Corrigendum to “Vapor-phase epitaxial growth of GaN films using Ga2O vapor and NH3” [Journal of Crystal Growth 350 (2012) 56–59] by Imade, Mamoru, Bu, Yuan, Sumi, Tomoaki, Kitamoto, Akira, Yoshimura, Masashi, Sasaki, Takatomo, Isemura, Masashi, Mori, Yusuke

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Homoepitaxial growth of a -plane GaN layers by reaction between Ga 2 O vapor and NH 3 gas by Sumi, Tomoaki, Taniyama, Yuuki, Takatsu, Hiroaki, Juta, Masami, Kitamoto, Akira, Imade, Mamoru, Yoshimura, Masashi, Isemura, Masashi, Mori, Yusuke

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Homoepitaxial growth of a-plane GaN layers by reaction between Ga sub(2) O vapor and NH sub(3) gas by Sumi, Tomoaki, Taniyama, Yuuki, Takatsu, Hiroaki, Juta, Masami, Kitamoto, Akira, Imade, Mamoru, Yoshimura, Masashi, Isemura, Masashi, Mori, Yusuke

“…Growth of high-quality a-plane GaN layers was performed by reaction between Ga sub(2) O vapor and NH3 gas at a high temperature. Smooth a-plane GaN epitaxial…”
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Growth of GaN layers using Ga 2 O vapor obtained from Ga and H 2 O vapor by Sumi, Tomoaki, Taniyama, Yuuki, Takatsu, Hiroaki, Juta, Masami, Kitamoto, Akira, Imade, Mamoru, Yoshimura, Masashi, Isemura, Masashi, Mori, Yusuke

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Growth of GaN layers using Ga sub(2) O vapor obtained from Ga and H sub(2) O vapor by Sumi, Tomoaki, Taniyama, Yuuki, Takatsu, Hiroaki, Juta, Masami, Kitamoto, Akira, Imade, Mamoru, Yoshimura, Masashi, Isemura, Masashi, Mori, Yusuke

“…In this study, we performed growth of GaN layers using Ga sub(2) O vapor synthesized from Ga and H sub(2) O vapor. In this process, we employed H sub(2) O…”
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Pressure-Dependent Raman Scattering Spectrum of Piezoelectric (Li,Na,K)NbO 3 Lead-Free Ceramics by Kakimoto, Ken-ichi, Sumi, Tomoaki, Kagomiya, Isao

“…High-pressure Raman scattering experiments have been carried out for (Na 0.5 K 0.5 )NbO 3 and Li x (Na 0.5 K 0.5 ) 1- x NbO 3 (abbreviated as LNKN-100 x )…”
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Low resistive and low dislocation GaN wafer produced by OVPE method by Takino, Junichi, Sumi, Tomoaki, Okayama, Yoshio, Nobuoka, Masaki, Kitamoto, Akira, Imanishi, Msayuki, Yoshimura, Masashi, Mori, Yusuke

“…We have been developing Oxide Vapor Phase Epitaxy (OVPE) method for manufacturing of high quality and low cost GaN wafers. In a previous research, high…”
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