published_papers
"タイトル(日本語)","タイトル(英語)","著者(日本語)","著者(英語)","担当区分","概要(日本語)","概要(英語)","出版者・発行元(日本語)","出版者・発行元(英語)","出版年月","誌名(日本語)","誌名(英語)","巻","号","開始ページ","終了ページ","記述言語","査読の有無","招待の有無","掲載種別","国際・国内誌","国際共著","DOI","ISSN","eISSN","URL","URL2","主要な業績かどうか","公開の有無"
"Plasma-Assisted Annealing of Pt-Doped Rutile TiO2 Nanoparticles for Enhanced Decomposition and Bacterial Inactivation under General Lighting","Plasma-Assisted Annealing of Pt-Doped Rutile TiO2 Nanoparticles for Enhanced Decomposition and Bacterial Inactivation under General Lighting","Retsuo Kawakami, Yuta Makino, Shin-ichiro Yanagiya, Akihiro Shirai, Masahito Niibe, Yoshitaka Nakano","Retsuo Kawakami, Yuta Makino, Shin-ichiro Yanagiya, Akihiro Shirai, Masahito Niibe, Yoshitaka Nakano","null","null","null","null","null","2024-01-11","Journal of Vacuum Science and Technology. B, Nanotechnology & Microelectronics : Materials, Processing, Measurement, & Phenomena : JVST B","Journal of Vacuum Science and Technology. B, Nanotechnology & Microelectronics : Materials, Processing, Measurement, & Phenomena : JVST B","Vol.42","null","012203:1","012203:12","eng","true","null","scientific_journal","null","null","10.1116/6.0003101","2166-2746","null","null","null","null","null"
"Remote Bactericidal Effect of Anatase TiO2 Photocatalytic Nanoparticles Annealed with Low-Temperature O2 Plasma","Remote Bactericidal Effect of Anatase TiO2 Photocatalytic Nanoparticles Annealed with Low-Temperature O2 Plasma","Retsuo Kawakami, Yuki Takao, Akihiro Shirai, Takashi Mukai","Retsuo Kawakami, Yuki Takao, Akihiro Shirai, Takashi Mukai","null","The remote bactericidal effect of TiO photocatalyst, i.e., the bactericidal effect away from the photocatalyst, was successfully achieved using a humidified airflow. The TiO photocatalyst used was anatase-type TiO nanoparticles (NPs) annealed with a low-temperature O plasma. For comparison, anatase-type TiO NPs annealed in the air were used. The bacteria, Bacillus subtilis, were placed away from the TiO NPs. The plasma-assisted-annealed TiO NPs significantly inactivated 99% of the bacterial cells in 5 h, whereas the pristine and air-annealed TiO NPs inactivated 88-90% of the bacterial cells. The remote bactericidal effect of plasmaassisted-annealed TiO NPs would be attributed to a larger amount of HO molecules traveled by the airflow from the TiO NPs. The molecules were generated by chemically reacting more photoexcited carriers on the TiO surface with HO and O in the airflow. These photoexcited carriers originated from more oxygen-based species adsorbed and more oxygen vacancies introduced on the TiO surface by the plasma-assisted-annealing.","The remote bactericidal effect of TiO photocatalyst, i.e., the bactericidal effect away from the photocatalyst, was successfully achieved using a humidified airflow. The TiO photocatalyst used was anatase-type TiO nanoparticles (NPs) annealed with a low-temperature O plasma. For comparison, anatase-type TiO NPs annealed in the air were used. The bacteria, Bacillus subtilis, were placed away from the TiO NPs. The plasma-assisted-annealed TiO NPs significantly inactivated 99% of the bacterial cells in 5 h, whereas the pristine and air-annealed TiO NPs inactivated 88-90% of the bacterial cells. The remote bactericidal effect of plasmaassisted-annealed TiO NPs would be attributed to a larger amount of HO molecules traveled by the airflow from the TiO NPs. The molecules were generated by chemically reacting more photoexcited carriers on the TiO surface with HO and O in the airflow. These photoexcited carriers originated from more oxygen-based species adsorbed and more oxygen vacancies introduced on the TiO surface by the plasma-assisted-annealing.","null","null","2022-12","Biocontrol Science","Biocontrol Science","Vol.27","No.4","217","222","eng","true","null","scientific_journal","null","null","10.4265/bio.27.217","1884-0205","null","null","null","null","null"
"Bactericidal Effects of Low-Temperature Atmospheric-Pressure Air Plasma Jets with No Damage to Plant Nutrient Solutions","Bactericidal Effects of Low-Temperature Atmospheric-Pressure Air Plasma Jets with No Damage to Plant Nutrient Solutions","Retsuo Kawakami, Mutsumi Aihara, Takuto Izumi, Akihiro Shirai, Mukai Takashi","Retsuo Kawakami, Mutsumi Aihara, Takuto Izumi, Akihiro Shirai, Mukai Takashi","null","null","null","null","null","2022-11","Biochemical Engineering Journal","Biochemical Engineering Journal","Vol.187","null","108661:1","108661:9","eng","true","null","scientific_journal","null","null","10.1016/j.bej.2022.108661","1369-703X","null","null","null","null","null"
"Photocatalytic Activity Enhancement of Anatase/Rutile-Mixed Phase TiO2 Nanoparticles Annealed with Low-Temperature O2 Plasma","Photocatalytic Activity Enhancement of Anatase/Rutile-Mixed Phase TiO2 Nanoparticles Annealed with Low-Temperature O2 Plasma","Retsuo Kawakami, Yuki Mimoto, Shin-ichiro Yanagiya, Akihiro Shirai, Masahito Niibe, Yoshitaka Nakano, Takashi Mukai","Retsuo Kawakami, Yuki Mimoto, Shin-ichiro Yanagiya, Akihiro Shirai, Masahito Niibe, Yoshitaka Nakano, Takashi Mukai","null","null","null","null","null","2021-12-21","Physica Status Solidi (A) Applications and Materials Science","Physica Status Solidi (A) Applications and Materials Science","Vol.218","null","2100536-1","2100536-13","eng","true","null","scientific_journal","null","null","10.1002/pssa.202100536","1862-6319","null","null","null","null","null"
"Effects of Nonequilibrium Atmospheric-Pressure O2 Plasma-Assisted Annealing on Anatase TiO2 Nanoparticles","Effects of Nonequilibrium Atmospheric-Pressure O2 Plasma-Assisted Annealing on Anatase TiO2 Nanoparticles","Retsuo Kawakami, Yuki Yoshitani, Akihiro Shirai, Shin-ichiro Yanagiya, Hirofumi Koide, Yuki Mimoto, Kosuke Kajikawa, Masahito Niibe, Yoshitaka Nakano, Chisato Azuma, Takashi Mukai","Retsuo Kawakami, Yuki Yoshitani, Akihiro Shirai, Shin-ichiro Yanagiya, Hirofumi Koide, Yuki Mimoto, Kosuke Kajikawa, Masahito Niibe, Yoshitaka Nakano, Chisato Azuma, Takashi Mukai","null","null","null","null","null","2020-05-20","Applied Surface Science","Applied Surface Science","Vol.526","null","146684:1","146684:12","eng","true","null","scientific_journal","null","null","10.1016/j.apsusc.2020.146684","0169-4332","null","null","null","null","null"
"Effects of Air-Based Nonequilibrium Atmospheric Pressure Plasma Jet Treatment on Characteristics of Polypropylene Film Surfaces","Effects of Air-Based Nonequilibrium Atmospheric Pressure Plasma Jet Treatment on Characteristics of Polypropylene Film Surfaces","Retsuo Kawakami, Yuki Yoshitani, Kimiaki Mitani, Masahito Niibe, Yoshitaka Nakano, Chisato Azuma, Takashi Mukai","Retsuo Kawakami, Yuki Yoshitani, Kimiaki Mitani, Masahito Niibe, Yoshitaka Nakano, Chisato Azuma, Takashi Mukai","null","null","null","null","null","2020-02-18","Applied Surface Science","Applied Surface Science","Vol.509","null","144910:1","144910:10","eng","true","null","scientific_journal","null","null","10.1016/j.apsusc.2019.144910","0169-4332","null","null","null","null","null"
"Steady-state and time-resolved optical properties of multilayer film of titanium dioxide sandwiched by gold nanoparticles and gold thin film","Steady-state and time-resolved optical properties of multilayer film of titanium dioxide sandwiched by gold nanoparticles and gold thin film","Shin-ichiro Yanagiya, Toshihiko Takahata, Yuuki Yoshitani, Retsuo Kawakami, Akihiro Furube","Shin-ichiro Yanagiya, Toshihiko Takahata, Yuuki Yoshitani, Retsuo Kawakami, Akihiro Furube","null","We proposed metal insulator (MI) and metal insulator metal (MIM) structures of titanium dioxide (TiO2) sandwiched by gold nanoparticles (AuNPs) layer and gold sputtered thin film (only for the MIM film) to couple localized plasmon mode of AuNP with multi reflection mode and/or cavity resonator mode of TiO2. The optical extinctions of MI and MIM with differing TiO2 thickness were studied theoretically by finite element method simulation and experimentally by optical spectrometry. The extinction peaks of MI and MIM shifted by exchanging the surrounding medium from air to TiO2. The interference of TiO2 in MI structure also affected the extinction spectra showing the oscillation along the spectrum of AuNP in TiO2. Then, the extinction degree of MIM was higher than that of MI because of the coupling between cavity resonance mode with localized plasmon mode and interband transition in AuNPs. In addition, the cross section of MI and MIM films were observed by scanning electron microscopy. The surface of thinner film was rough because TiO2 heterogeneously grew from AuNP. The irregular growth of TiO2 might have induced the wide range extinction in 300 2500 nm after Au thin film deposition. The transient absorption spectra using a femtosecond laser were also carried out under the condition of 800 nm for excitation laser and 950 nm for probe laser. The long lived electron (∼1 ns) was observed in thick MIM film as a result of hot electron transfer from the gold nanostructure in the film.","We proposed metal insulator (MI) and metal insulator metal (MIM) structures of titanium dioxide (TiO2) sandwiched by gold nanoparticles (AuNPs) layer and gold sputtered thin film (only for the MIM film) to couple localized plasmon mode of AuNP with multi reflection mode and/or cavity resonator mode of TiO2. The optical extinctions of MI and MIM with differing TiO2 thickness were studied theoretically by finite element method simulation and experimentally by optical spectrometry. The extinction peaks of MI and MIM shifted by exchanging the surrounding medium from air to TiO2. The interference of TiO2 in MI structure also affected the extinction spectra showing the oscillation along the spectrum of AuNP in TiO2. Then, the extinction degree of MIM was higher than that of MI because of the coupling between cavity resonance mode with localized plasmon mode and interband transition in AuNPs. In addition, the cross section of MI and MIM films were observed by scanning electron microscopy. The surface of thinner film was rough because TiO2 heterogeneously grew from AuNP. The irregular growth of TiO2 might have induced the wide range extinction in 300 2500 nm after Au thin film deposition. The transient absorption spectra using a femtosecond laser were also carried out under the condition of 800 nm for excitation laser and 950 nm for probe laser. The long lived electron (∼1 ns) was observed in thick MIM film as a result of hot electron transfer from the gold nanostructure in the film.","null","null","2019-05","ChemNanoMat : Chemistry of Nanomaterials for Energy, Biology and More","ChemNanoMat : Chemistry of Nanomaterials for Energy, Biology and More","Vol.5","null","1015","1020","eng","true","true","scientific_journal","null","null","10.1002/cnma.201900042","2199-692X","null","null","null","null","null"
"Effects of Ultraviolet Wavelength and Intensity on AlGaN Thin Film Surfaces Irradiated Simultaneously with CF4 Plasma and Ultraviolet","Effects of Ultraviolet Wavelength and Intensity on AlGaN Thin Film Surfaces Irradiated Simultaneously with CF4 Plasma and Ultraviolet","Retsuo Kawakami, Masahito Niibe, Yoshitaka Nakano, Shin-ichiro Yanagiya, Yuki Yoshitani, Chisato Azuma, Takashi Mukai","Retsuo Kawakami, Masahito Niibe, Yoshitaka Nakano, Shin-ichiro Yanagiya, Yuki Yoshitani, Chisato Azuma, Takashi Mukai","null","null","null","null","null","2019-01-01","Vacuum","Vacuum","Vol.159","null","45","50","eng","true","null","scientific_journal","null","null","10.1016/j.vacuum.2018.10.017","0042-207X","null","null","null","null","null"
"Characteristics of TiO2 Thin Films Surfaces Treated by O2 Plasma in Dielectric Barrier Discharge with the Assistance of External Heating","Characteristics of TiO2 Thin Films Surfaces Treated by O2 Plasma in Dielectric Barrier Discharge with the Assistance of External Heating","Retsuo Kawakami, Masahito Niibe, Yoshitaka Nakano, Yuma Araki, Yuki Yoshitani, Chisato Azuma, Takashi Mukai","Retsuo Kawakami, Masahito Niibe, Yoshitaka Nakano, Yuma Araki, Yuki Yoshitani, Chisato Azuma, Takashi Mukai","null","null","null","null","null","2018-03-27","Vacuum","Vacuum","Vol.152","null","265","271","eng","true","null","scientific_journal","null","null","10.1016/j.vacuum.2018.03.051","0042-207X","null","null","null","null","null"
"Characteristics of N2 and O2 Plasma-Induced Damages on AlGaN Thin Film Surfaces","Characteristics of N2 and O2 Plasma-Induced Damages on AlGaN Thin Film Surfaces","Retsuo Kawakami, Masahito Niibe, Yoshitaka Nakano, Ryo Tanaka, Chisato Azuma, Takashi Mukai","Retsuo Kawakami, Masahito Niibe, Yoshitaka Nakano, Ryo Tanaka, Chisato Azuma, Takashi Mukai","null","null","null","null","null","2017-11-01","Physica Status Solidi (A) Applications and Materials Science","Physica Status Solidi (A) Applications and Materials Science","Vol.214","No.11","1700393-1","1700393-7","eng","true","null","scientific_journal","null","null","10.1002/pssa.201700393","1862-6300","null","null","null","null","null"
"Generation of Electrical Damage in n-GaN Films Following Treatment in a CF4 Plasma","Generation of Electrical Damage in n-GaN Films Following Treatment in a CF4 Plasma","Yoshitaka Nakano, Retsuo Kawakami, Masahito Niibe","Yoshitaka Nakano, Retsuo Kawakami, Masahito Niibe","null","null","null","null","null","2017-10-13","Applied Physics Express","Applied Physics Express","Vol.10","null","116201-1","116201-4","eng","true","null","scientific_journal","null","null","10.7567/APEX.10.116201","1882-0786","null","null","null","null","null"
"AlGaN Surfaces Etched by CF4 Plasma with and without the Assistance of Near-Ultraviolet Irradiation","AlGaN Surfaces Etched by CF4 Plasma with and without the Assistance of Near-Ultraviolet Irradiation","Retsuo Kawakami, Masahito Niibe, Yoshitaka Nakano, Takashi Mukai","Retsuo Kawakami, Masahito Niibe, Yoshitaka Nakano, Takashi Mukai","null","null","null","null","null","2017-02-01","Vacuum","Vacuum","Vol.136","null","28","35","eng","true","null","scientific_journal","null","null","10.1016/j.vacuum.2016.11.016","0042-207X","null","null","null","null","null"
"Damage Characteristics of n-GaN Crystal Etched with N2 Plasma by Soft X-Ray Absorption Spectroscopy","Damage Characteristics of n-GaN Crystal Etched with N2 Plasma by Soft X-Ray Absorption Spectroscopy","Masahito Niibe, Takuya Kotaka, Retsuo Kawakami, Yoshitaka Nakano, Takashi Mukai","Masahito Niibe, Takuya Kotaka, Retsuo Kawakami, Yoshitaka Nakano, Takashi Mukai","null","null","null","null","null","2016-01-23","e-Journal of Surface Science and Nanotechnology","e-Journal of Surface Science and Nanotechnology","Vol.14","null","9","13","eng","true","null","scientific_journal","null","null","10.1380/ejssnt.2016.9","1348-0391","null","null","null","null","null"
"Surface Analysis of AlGaN Treated with CF4 and Ar Plasma Etching","Surface Analysis of AlGaN Treated with CF4 and Ar Plasma Etching","Shohdai Hirai, Masahito Niibe, Retsuo Kawakami, Tatsuo Shirahama, Yoshitaka Nakano, Takashi Mukai","Shohdai Hirai, Masahito Niibe, Retsuo Kawakami, Tatsuo Shirahama, Yoshitaka Nakano, Takashi Mukai","null","null","null","null","null","2015-12-19","e-Journal of Surface Science and Nanotechnology","e-Journal of Surface Science and Nanotechnology","Vol.13","null","481","487","eng","true","null","scientific_journal","null","null","10.1380/ejssnt.2015.481","1348-0391","null","null","null","null","null"
"Comparison between AlGaN Surfaces Etched by Carbon Tetrafluoride and Argon Plasmas: Effect of the Fluorine Impurities Incorporated in the Surface","Comparison between AlGaN Surfaces Etched by Carbon Tetrafluoride and Argon Plasmas: Effect of the Fluorine Impurities Incorporated in the Surface","Retsuo Kawakami, Masahito Niibe, Yoshitaka Nakano, Tatsuo Shirahama, Shodai Hirai, Takashi Mukai","Retsuo Kawakami, Masahito Niibe, Yoshitaka Nakano, Tatsuo Shirahama, Shodai Hirai, Takashi Mukai","null","null","null","null","null","2015-06-18","Vacuum","Vacuum","Vol.119","null","264","269","eng","true","null","scientific_journal","null","null","10.1016/j.vacuum.2015.06.002","0042-207X","null","null","null","null","null"
"Ar+-Irradiation-Induced Damage in Hydride Vapor-Phase Epitaxy GaN Films","Ar+-Irradiation-Induced Damage in Hydride Vapor-Phase Epitaxy GaN Films","Yoshitaka Nakano, Daisuke Ogawa, Keiji Nakamura, Retsuo Kawakami, Masahito Niibe","Yoshitaka Nakano, Daisuke Ogawa, Keiji Nakamura, Retsuo Kawakami, Masahito Niibe","null","null","null","null","null","2015-06-15","Journal of Vacuum Science & Technology A","Journal of Vacuum Science & Technology A","Vol.33","null","043002-1","043002-5","eng","true","null","scientific_journal","null","null","10.1116/1.4922593","0734-2101","null","null","null","null","null"
"Recovery of X-ray Absorption Spectral Profile in Etched TiO2 Thin Films","Recovery of X-ray Absorption Spectral Profile in Etched TiO2 Thin Films","Keiji Sano, Masahito Niibe, Retsuo Kawakami, Yoshitaka Nakano","Keiji Sano, Masahito Niibe, Retsuo Kawakami, Yoshitaka Nakano","null","null","null","null","null","2015-04-08","Journal of Vacuum Science & Technology A","Journal of Vacuum Science & Technology A","Vol.33","No.3","031403-1","031403-4","eng","true","null","scientific_journal","null","null","10.1116/1.4917012","0734-2101","null","null","null","null","null"
"Electrical Investigation of Deep-Level Defects Introduced in AlGaN/GaN Heterostructures by CF4 Plasma Treatments","Electrical Investigation of Deep-Level Defects Introduced in AlGaN/GaN Heterostructures by CF4 Plasma Treatments","Retsuo Kawakami, Yoshitaka Nakano, Masahito Niibe, Tatsuo Shirahama, Takashi Mukai","Retsuo Kawakami, Yoshitaka Nakano, Masahito Niibe, Tatsuo Shirahama, Takashi Mukai","null","null","null","null","null","2015-02-24","ECS Solid State Letters","ECS Solid State Letters","Vol.4","No.4","36","38","eng","true","null","scientific_journal","null","null","10.1149/2.0011505ssl","2162-8742","null","null","null","null","null"
"Optical and Electrical Investigation of Ar+-Irradiated GaN","Optical and Electrical Investigation of Ar+-Irradiated GaN","Chen Miao-Gen, Keiji Nakamura, Qiu Yan-Qing, Daisuke Ogawa, Retsuo Kawakami, Masahito Niibe, Yoshitaka Nakano","Chen Miao-Gen, Keiji Nakamura, Qiu Yan-Qing, Daisuke Ogawa, Retsuo Kawakami, Masahito Niibe, Yoshitaka Nakano","null","null","null","null","null","2014-11","Applied Physics Express","Applied Physics Express","Vol.7","No.11","111003-1","111003-3","eng","true","null","scientific_journal","null","null","10.7567/APEX.7.111003","1882-0786","null","null","null","null","null"
"Damage Characteristics of n-GaN Thin Film Surfaces Etched by Ultraviolet Light-Assisted Helium Plasmas","Damage Characteristics of n-GaN Thin Film Surfaces Etched by Ultraviolet Light-Assisted Helium Plasmas","Retsuo Kawakami, Masahito Niibe, Yoshitaka Nakano, Tatsuo Shirahama, Kazuma Aoki, Kenta Oba, Mari Takabatake, Takashi Mukai","Retsuo Kawakami, Masahito Niibe, Yoshitaka Nakano, Tatsuo Shirahama, Kazuma Aoki, Kenta Oba, Mari Takabatake, Takashi Mukai","null","null","null","null","null","2014-10","Thin Solid Films","Thin Solid Films","Vol.570","null","81","86","eng","true","null","scientific_journal","null","null","10.1016/j.tsf.2014.09.019","0040-6090","null","null","null","null","null"
"Surface Damage of 6H-SiC Originating from Argon Plasma Irradiation","Surface Damage of 6H-SiC Originating from Argon Plasma Irradiation","Retsuo Kawakami, Niibe Masahito, Takeuchi Hideo, Konishi Masashi, Mori Yuta, Shirahama Tatsuo, Yamada Tetsuya, Tominaga Kikuo","Retsuo Kawakami, Niibe Masahito, Takeuchi Hideo, Konishi Masashi, Mori Yuta, Shirahama Tatsuo, Yamada Tetsuya, Tominaga Kikuo","null","null","null","null","null","2013-11-11","Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms","Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms","Vol.315","null","213","217","null","true","null","scientific_journal","null","null","10.1016/j.nimb.2013.05.084","0168-583X","null","null","null","null","null"
"Damage characteristics of n-GaN thin film surfaces etched by N2 plasmas","Damage characteristics of n-GaN thin film surfaces etched by N2 plasmas","Retsuo Kawakami, Niibe Masahito, Nakano Yoshitaka, Shirahama Tatsuo, Yamada Tetsuya, Aoki Kazuma, Takabatake Mari, Tominaga Kikuo, Mukai Takashi","Retsuo Kawakami, Niibe Masahito, Nakano Yoshitaka, Shirahama Tatsuo, Yamada Tetsuya, Aoki Kazuma, Takabatake Mari, Tominaga Kikuo, Mukai Takashi","null","null","null","null","null","2013-11-07","Physica Status Solidi (C) Current Topics in Solid State Physics","Physica Status Solidi (C) Current Topics in Solid State Physics","Vol.10","No.11","1553","1556","eng","true","null","scientific_journal","null","null","10.1002/pssc.201300190","1610-1642","null","null","null","null","null"
"Characteristics of TiO2 Surfaces Etched by Capacitively Coupled Radio Frequency N2 and He Plasmas","Characteristics of TiO2 Surfaces Etched by Capacitively Coupled Radio Frequency N2 and He Plasmas","Retsuo Kawakami, Niibe Masahito, Nakano Yoshitaka, Konishi Masashi, Mori Yuta, Takeuchi Hideo, Shirahama Tatsuo, Yamada Tetsuya, Tominaga Kikuo","Retsuo Kawakami, Niibe Masahito, Nakano Yoshitaka, Konishi Masashi, Mori Yuta, Takeuchi Hideo, Shirahama Tatsuo, Yamada Tetsuya, Tominaga Kikuo","null","null","null","null","null","2013-06-13","Journal of Physics: Conference Series","Journal of Physics: Conference Series","Vol.441","null","012038-1","012038-6","eng","true","null","scientific_journal","null","null","10.1088/1742-6596/441/1/012038","1742-6596","null","null","null","null","null"
"Comparison between Damage Characteristics of p- and n-GaN Surfaces Etched by Capacitively Coupled Radio Frequency Argon Plasmas","Comparison between Damage Characteristics of p- and n-GaN Surfaces Etched by Capacitively Coupled Radio Frequency Argon Plasmas","Retsuo Kawakami, Niibe Masahito, Nakano Yoshitaka, Konishi Masashi, Mori Yuta, Takeichi Atsushi, Tominaga Kikuo, Mukai Takashi","Retsuo Kawakami, Niibe Masahito, Nakano Yoshitaka, Konishi Masashi, Mori Yuta, Takeichi Atsushi, Tominaga Kikuo, Mukai Takashi","null","Damage characteristics of p-GaN surfaces etched by capacitively coupled radio frequency Ar plasma at various gas pressures have been studied in terms of the ultraviolet (UV) light irradiation effect. The UV light corresponding to Ar II is emitted from the plasma at high gas pressures from 50 to 100 mTorr, whereas no UV light is emitted at a low gas pressure of 10 mTorr. The result of the etched p-GaN surface is compared with that of the etched n-GaN surface. The difference between the results of the p- and n-GaN surfaces depends strongly on the gas pressure. Both the experimental N/Ga ratios at the p- and n-GaN surfaces etched at the low gas pressure decrease with increasing etching time. The decreases in the experimental N/Ga ratios agree with the simulation results that N atoms at the p- and n-GaN surfaces are preferentially removed by Ar+ions. The morphologies of the p- and n-GaN surfaces etched at the low gas pressure are similar to those of the as-grown surfaces. The damage characteristic of the p-GaN surface induced in the absence of the UV light irradiation also appears at the high gas pressures, although the p-GaN surfaces etched at the high gas pressures are irradiated with the emitted UV light. In contrast, both the experimental N/Ga ratios and morphologies of the n-GaN surfaces etched at the high gas pressures change with increasing etching time. The changes in the n-GaN surfaces probably result from the UV light irradiation.","Damage characteristics of p-GaN surfaces etched by capacitively coupled radio frequency Ar plasma at various gas pressures have been studied in terms of the ultraviolet (UV) light irradiation effect. The UV light corresponding to Ar II is emitted from the plasma at high gas pressures from 50 to 100 mTorr, whereas no UV light is emitted at a low gas pressure of 10 mTorr. The result of the etched p-GaN surface is compared with that of the etched n-GaN surface. The difference between the results of the p- and n-GaN surfaces depends strongly on the gas pressure. Both the experimental N/Ga ratios at the p- and n-GaN surfaces etched at the low gas pressure decrease with increasing etching time. The decreases in the experimental N/Ga ratios agree with the simulation results that N atoms at the p- and n-GaN surfaces are preferentially removed by Ar+ions. The morphologies of the p- and n-GaN surfaces etched at the low gas pressure are similar to those of the as-grown surfaces. The damage characteristic of the p-GaN surface induced in the absence of the UV light irradiation also appears at the high gas pressures, although the p-GaN surfaces etched at the high gas pressures are irradiated with the emitted UV light. In contrast, both the experimental N/Ga ratios and morphologies of the n-GaN surfaces etched at the high gas pressures change with increasing etching time. The changes in the n-GaN surfaces probably result from the UV light irradiation.","null","null","2013-05-20","Japanese Journal of Applied Physics","Japanese Journal of Applied Physics","Vol.52","null","05EC05-1","05EC05-5","eng","true","null","scientific_journal","null","null","10.7567/JJAP.52.05EC05","0021-4922","null","http://ci.nii.ac.jp/naid/150000106941/","null","null","null"
"Etching Damage and Its Recovery by Soft X-ray Irradiation Observed in Soft X-ray Absorption Spectra of TiO2 Thin Film","Etching Damage and Its Recovery by Soft X-ray Irradiation Observed in Soft X-ray Absorption Spectra of TiO2 Thin Film","Niibe Masahito, Sano Keiji, Kotaka Takuya, Retsuo Kawakami, Tominaga Kikuo, Nakano Yoshitaka","Niibe Masahito, Sano Keiji, Kotaka Takuya, Retsuo Kawakami, Tominaga Kikuo, Nakano Yoshitaka","null","null","null","null","null","2013-03-22","Journal of Applied Physics","Journal of Applied Physics","Vol.113","No.12","126101-1","126101-3","eng","true","null","scientific_journal","null","null","10.1063/1.4798301","0021-8979","null","null","null","null","null"
"Effect of UV Irradiation on Ar-Plasma Etching Characteristics of GaN","Effect of UV Irradiation on Ar-Plasma Etching Characteristics of GaN","Yoshitaka Nakano, Keiji Nakamura, Masahito Niibe, Retsuo Kawakami, Noriyoshi Ito, Takuya Kotaka, Kikuo Tominaga","Yoshitaka Nakano, Keiji Nakamura, Masahito Niibe, Retsuo Kawakami, Noriyoshi Ito, Takuya Kotaka, Kikuo Tominaga","null","null","null","null","null","2013-01-21","ECS Journal of Solid State Science and Technology","ECS Journal of Solid State Science and Technology","Vol.2","No.3","110","113","eng","true","null","scientific_journal","null","null","10.1149/2.004304jss","2162-8769","null","null","null","null","null"
"Damage Analysis of n-GaN Crystal Etched with He and N2 Plasmas","Damage Analysis of n-GaN Crystal Etched with He and N2 Plasmas","Niibe Masahito, Kotaka Takuya, Retsuo Kawakami, Nakano Yoshitaka, Inaoka Takeshi, Tominaga Kikuo, Mukai Takashi","Niibe Masahito, Kotaka Takuya, Retsuo Kawakami, Nakano Yoshitaka, Inaoka Takeshi, Tominaga Kikuo, Mukai Takashi","null","To understand the details of etching-induced damage on a GaN surface, n-GaN crystals were plasma-etched with He and N2 gases. The etched surfaces were analyzed by X-ray photoelectron spectroscopy (XPS) and soft X-ray absorption spectroscopy (XAS) methods. The composition of the surface etched with He plasma changed significantly to being Ga-rich with the N/Ga ratio nearly equaling 0.4--0.5. The ratio of the surface etched with N2 plasma was about 0.6. The shape of the near-edge X-ray absorption fine structure (NEXAFS) of the N-K edge deformed with increasing gas pressure and processing time. The deformation can be explained by the increase in the band widths of a number of peaks in the NEXAFS spectra owing to the increase in the degree of structural disorder in the crystal. The increase in band width for the surface etched with N2 plasma was larger than that for the surface etched with He plasma. The above results can be explained with the model of the elastic energy transfer ratio of He+ and N2+ ions incident on the solid surface.","To understand the details of etching-induced damage on a GaN surface, n-GaN crystals were plasma-etched with He and N2 gases. The etched surfaces were analyzed by X-ray photoelectron spectroscopy (XPS) and soft X-ray absorption spectroscopy (XAS) methods. The composition of the surface etched with He plasma changed significantly to being Ga-rich with the N/Ga ratio nearly equaling 0.4--0.5. The ratio of the surface etched with N2 plasma was about 0.6. The shape of the near-edge X-ray absorption fine structure (NEXAFS) of the N-K edge deformed with increasing gas pressure and processing time. The deformation can be explained by the increase in the band widths of a number of peaks in the NEXAFS spectra owing to the increase in the degree of structural disorder in the crystal. The increase in band width for the surface etched with N2 plasma was larger than that for the surface etched with He plasma. The above results can be explained with the model of the elastic energy transfer ratio of He+ and N2+ ions incident on the solid surface.","null","null","2013-01-21","Japanese Journal of Applied Physics","Japanese Journal of Applied Physics","Vol.52","null","01AF04-1","01AF04-5","eng","true","null","scientific_journal","null","null","10.7567/JJAP.52.01AF04","0021-4922","null","http://ci.nii.ac.jp/naid/150000106327/","null","null","null"
"Capacitively Coupled Radio Frequency Nitrogen Plasma Etch Damage to N-Type Gallium Nitride","Capacitively Coupled Radio Frequency Nitrogen Plasma Etch Damage to N-Type Gallium Nitride","Retsuo Kawakami, Atsushi Takeichi, Masahito Niibe, Masashi Konishi, Yuta Mori, Takuya Kotaka, Takeshi Inaoka, Kikuo Tominaga, Takashi Mukai","Retsuo Kawakami, Atsushi Takeichi, Masahito Niibe, Masashi Konishi, Yuta Mori, Takuya Kotaka, Takeshi Inaoka, Kikuo Tominaga, Takashi Mukai","null","null","null","null","null","2013-01-05","Vacuum","Vacuum","Vol.87","null","136","140","eng","true","null","scientific_journal","null","null","10.1016/j.vacuum.2012.07.006","0042-207X","null","null","null","null","null"
"Characteristics of TiO2 Thin Film Surfaces Treated by Helium and Air Dielectric Barrier Discharge Plasmas","Characteristics of TiO2 Thin Film Surfaces Treated by Helium and Air Dielectric Barrier Discharge Plasmas","Retsuo Kawakami, Niibe Masahito, Takeichi Atsushi, Mori Yuta, Konishi Masashi, Kotaka Takuya, Matsunaga Fumihiko, Takasaki Toshihide, Kitano Takanori, Miyazaki Takahiro, Inaoka Takeshi, Tominaga Kikuo","Retsuo Kawakami, Niibe Masahito, Takeichi Atsushi, Mori Yuta, Konishi Masashi, Kotaka Takuya, Matsunaga Fumihiko, Takasaki Toshihide, Kitano Takanori, Miyazaki Takahiro, Inaoka Takeshi, Tominaga Kikuo","null","The characteristics of TiO2 thin film surfaces treated with He and air dielectric barrier discharge (DBD) plasmas at different gas pressures are investigated. There is a difference between the two DBD plasma characteristics: for He-DBD, which is an atmospheric pressure glow discharge (APGD), the breakdown voltage and discharge current hardly change with increasing gas pressure, whereas for air-DBD, which is basically a filamentary discharge, they increase with increasing gas pressure. There is also a difference between the characteristics of TiO2 surfaces treated with the two DBDs. The surface roughness for He-DBD is lower than the roughness of the as-grown surface, whereas that for air-DBD is higher. The surface hydrophilicity for He-DBD is more enhanced than the hydrophilicity of the as-grown surface regardless of UV irradiation. The hydrophilicity for air-DBD is dependent on UV irradiation. It is more enhanced with UV irradiation; it is not improved adequately without UV irradiation.","The characteristics of TiO2 thin film surfaces treated with He and air dielectric barrier discharge (DBD) plasmas at different gas pressures are investigated. There is a difference between the two DBD plasma characteristics: for He-DBD, which is an atmospheric pressure glow discharge (APGD), the breakdown voltage and discharge current hardly change with increasing gas pressure, whereas for air-DBD, which is basically a filamentary discharge, they increase with increasing gas pressure. There is also a difference between the characteristics of TiO2 surfaces treated with the two DBDs. The surface roughness for He-DBD is lower than the roughness of the as-grown surface, whereas that for air-DBD is higher. The surface hydrophilicity for He-DBD is more enhanced than the hydrophilicity of the as-grown surface regardless of UV irradiation. The hydrophilicity for air-DBD is dependent on UV irradiation. It is more enhanced with UV irradiation; it is not improved adequately without UV irradiation.","null","null","2012-08-20","Japanese Journal of Applied Physics, Part 1 (Regular Papers & Short Notes)","Japanese Journal of Applied Physics, Part 1 (Regular Papers & Short Notes)","Vol.51","No.8","08HB04-1","08HB04-6","eng","true","null","scientific_journal","null","null","10.1143/JJAP.51.08HB04","0021-4922","null","http://ci.nii.ac.jp/naid/150000103811/","null","null","null"
"Damage Analysis of Plasma-etched n-GaN Crystal Surface by Nitrogen K-edge NEXAFS Spectroscopy","Damage Analysis of Plasma-etched n-GaN Crystal Surface by Nitrogen K-edge NEXAFS Spectroscopy","Niibe Masahito, Kotaka Takuya, Retsuo Kawakami, Inaoka Takeshi, Tominaga Kikuo, Mukai Takashi","Niibe Masahito, Kotaka Takuya, Retsuo Kawakami, Inaoka Takeshi, Tominaga Kikuo, Mukai Takashi","null","The surface of an n-GaN crystal etched with an Ar, Kr, or Xe plasma was analyzed by nitrogen K near-edge X-ray absorption fine structure (NEXAFS) spectroscopy. The NEXAFS spectroscopy was carried out with the total electron yield (TEY) method in a sample current mode and the total fluorescence yield (TFY) method by measuring the amount of fluorescence using a photodiode. The shapes of the spectra of Ar plasma-etched samples obtained by the TEY method became smooth (blunt) with increasing Ar pressure from 10 to 200 mTorr. However, those obtained by the TFY method did not change with pressure. These results indicate that the etching damage was restricted in the shallow region of less than a few nm from the surface. A change in the NEXAFS spectral shape of Kr or Xe plasma-etched samples was not observed even when measured by the TEY method. This result indicates that the surface damage in Kr or Xe plasma-etched samples was less pronounced than that in Ar plasma-etched samples.","The surface of an n-GaN crystal etched with an Ar, Kr, or Xe plasma was analyzed by nitrogen K near-edge X-ray absorption fine structure (NEXAFS) spectroscopy. The NEXAFS spectroscopy was carried out with the total electron yield (TEY) method in a sample current mode and the total fluorescence yield (TFY) method by measuring the amount of fluorescence using a photodiode. The shapes of the spectra of Ar plasma-etched samples obtained by the TEY method became smooth (blunt) with increasing Ar pressure from 10 to 200 mTorr. However, those obtained by the TFY method did not change with pressure. These results indicate that the etching damage was restricted in the shallow region of less than a few nm from the surface. A change in the NEXAFS spectral shape of Kr or Xe plasma-etched samples was not observed even when measured by the TEY method. This result indicates that the surface damage in Kr or Xe plasma-etched samples was less pronounced than that in Ar plasma-etched samples.","null","null","2012-01-20","Japanese Journal of Applied Physics, Part 1 (Regular Papers & Short Notes)","Japanese Journal of Applied Physics, Part 1 (Regular Papers & Short Notes)","Vol.51","No.1","01AB02-1","01AB02-4","eng","true","null","scientific_journal","null","null","10.1143/JJAP.51.01AB02","0021-4922","null","http://ci.nii.ac.jp/naid/150000105460/","null","null","null"
"Photoluminescence Study of Damage Introduced in GaN by Ar- and Kr-Plasmas Etching","Photoluminescence Study of Damage Introduced in GaN by Ar- and Kr-Plasmas Etching","Nakano Yoshitaka, Retsuo Kawakami, Niibe Masahito, Takeichi Atsushi, Inaoka Takeshi, Tominaga Kikuo","Nakano Yoshitaka, Retsuo Kawakami, Niibe Masahito, Takeichi Atsushi, Inaoka Takeshi, Tominaga Kikuo","null","null","null","null","null","2011-12-29","Materials Research Society Symposia Proceedings","Materials Research Society Symposia Proceedings","Vol.1396","No.mrsf11-1396-o07-36","1","6","eng","true","null","scientific_journal","null","null","10.1557/opl.2011.1533","1946-4274","null","null","null","null","null"
"Damage Characteristics of TiO2 Thin Film Surfaces Etched by Capacitively Coupled Radio Frequency Helium Plasmas","Damage Characteristics of TiO2 Thin Film Surfaces Etched by Capacitively Coupled Radio Frequency Helium Plasmas","Retsuo Kawakami, Takeichi Atsushi, Niibe Masahito, Inaoka Takeshi, Tominaga Kikuo","Retsuo Kawakami, Takeichi Atsushi, Niibe Masahito, Inaoka Takeshi, Tominaga Kikuo","null","null","null","null","null","2011-08-22","Japanese Journal of Applied Physics","Japanese Journal of Applied Physics","Vol.50","No.8","08KD01-1","08KD01-5","eng","true","null","scientific_journal","null","null","10.1143/JJAP.50.08KD01","0021-4922","null","http://ci.nii.ac.jp/naid/40018961090/","null","null","null"
"Synergy Effect of Xenon Plasma Ions and Ultraviolet Lights on GaN Etch Surface Damage and Modification","Synergy Effect of Xenon Plasma Ions and Ultraviolet Lights on GaN Etch Surface Damage and Modification","Retsuo Kawakami, Inaoka Takeshi, Tominaga Kikuo, Niibe Masahito, Mukai Takashi, Takeichi Atsushi, Fukudome Toshiaki","Retsuo Kawakami, Inaoka Takeshi, Tominaga Kikuo, Niibe Masahito, Mukai Takashi, Takeichi Atsushi, Fukudome Toshiaki","null","null","null","null","null","2011-03-30","Transactions of the Materials Research Society of Japan","Transactions of the Materials Research Society of Japan","Vol.36","No.1","75","78","eng","true","null","scientific_journal","null","null","10.14723/tmrsj.36.75","2188-1650","null","null","null","null","null"
"Surface analysis of n-GaN crystal damaged by RF-plasma-etching with Ar, Kr, and Xe gases","Surface analysis of n-GaN crystal damaged by RF-plasma-etching with Ar, Kr, and Xe gases","Niibe Masahito, Maeda Yoshie, Retsuo Kawakami, Inaoka Takeshi, Tominaga Kikuo, Mukai Takashi","Niibe Masahito, Maeda Yoshie, Retsuo Kawakami, Inaoka Takeshi, Tominaga Kikuo, Mukai Takashi","null","null","null","null","null","2011-02-15","Physica Status Solidi (C) Current Topics in Solid State Physics","Physica Status Solidi (C) Current Topics in Solid State Physics","Vol.8","No.2","435","437","eng","true","null","scientific_journal","null","null","10.1002/pssc.201000507","1610-1642","null","null","null","null","null"
"Etch-induced damage characteristics of n-GaN surfaces by capacitively coupled radio frequency He and Ar plasmas","Etch-induced damage characteristics of n-GaN surfaces by capacitively coupled radio frequency He and Ar plasmas","Retsuo Kawakami, Inaoka Takeshi, Tominaga Kikuo, Niibe Masahito, Mukai Takashi, Takeichi Atsushi, Fukudome Toshiaki","Retsuo Kawakami, Inaoka Takeshi, Tominaga Kikuo, Niibe Masahito, Mukai Takashi, Takeichi Atsushi, Fukudome Toshiaki","null","null","null","null","null","2011-02-15","Physica Status Solidi (C) Current Topics in Solid State Physics","Physica Status Solidi (C) Current Topics in Solid State Physics","Vol.8","No.2","441","443","eng","true","null","scientific_journal","null","null","10.1002/pssc.201000400","1610-1642","null","null","null","null","null"
"Effect of DBD Air Plasma Treatment on TiO2 Thin Film Surfaces","Effect of DBD Air Plasma Treatment on TiO2 Thin Film Surfaces","Retsuo Kawakami, Niibe Masahito, Fukudome Toshiaki, Takeichi Atsushi, Inaoka Takeshi, Tominaga Kikuo","Retsuo Kawakami, Niibe Masahito, Fukudome Toshiaki, Takeichi Atsushi, Inaoka Takeshi, Tominaga Kikuo","null","Surface treatment effect on TiO2 thin films with the anatase phase by dielectric barrier discharge (DBD) air plasmas has been investigated for a variety of gas pressures and treatment times. At a low gas pressure (100 hPa) at which a glow-like discharge plasma occurs, hydrophilicities of TiO2 thin films treated at 5 and 30 min are enhanced compared with that of the as-grown thin film. For the 5 min treatment, this trend is more pronounced probably due to oxygen absorbed on the surface from the air plasma. For the 30 min treatment, the enhanced hydrophilicity is probably due to oxygen vacancy created on the surface by a high fluence of the plasma. When the gas pressure increases to 400 hPa at which a streamer discharge plasma occurs, the hydrophilicity is more weakened than that of the as-grown thin film: the plasma-induced damage occurs regardless of the treatment time. This result would probably result from the higher discharge current and UV light intensity caused by the higher breakdown voltage based on Paschen's law.","Surface treatment effect on TiO2 thin films with the anatase phase by dielectric barrier discharge (DBD) air plasmas has been investigated for a variety of gas pressures and treatment times. At a low gas pressure (100 hPa) at which a glow-like discharge plasma occurs, hydrophilicities of TiO2 thin films treated at 5 and 30 min are enhanced compared with that of the as-grown thin film. For the 5 min treatment, this trend is more pronounced probably due to oxygen absorbed on the surface from the air plasma. For the 30 min treatment, the enhanced hydrophilicity is probably due to oxygen vacancy created on the surface by a high fluence of the plasma. When the gas pressure increases to 400 hPa at which a streamer discharge plasma occurs, the hydrophilicity is more weakened than that of the as-grown thin film: the plasma-induced damage occurs regardless of the treatment time. This result would probably result from the higher discharge current and UV light intensity caused by the higher breakdown voltage based on Paschen's law.","null","null","2011-01-04","Japanese Journal of Applied Physics, Part 1 (Regular Papers & Short Notes)","Japanese Journal of Applied Physics, Part 1 (Regular Papers & Short Notes)","Vol.50","No.1","01BE02-1","01BE02-5","eng","true","null","scientific_journal","null","null","10.1143/JJAP.50.01BE02","0021-4922","null","http://ci.nii.ac.jp/naid/150000055207/","null","null","null"
"Etch Damage Characteristics of TiO2 Thin Films by Capacitively Coupled RF Ar Plasmas","Etch Damage Characteristics of TiO2 Thin Films by Capacitively Coupled RF Ar Plasmas","Retsuo Kawakami, Tominaga Kikuo, Okada Kenji, Nouda Takahiro, Inaoka Takeshi, Takeichi Atsushi, Fukudome Toshiaki, Murao Kenichi","Retsuo Kawakami, Tominaga Kikuo, Okada Kenji, Nouda Takahiro, Inaoka Takeshi, Takeichi Atsushi, Fukudome Toshiaki, Murao Kenichi","null","null","null","null","null","2010-06","Vacuum","Vacuum","Vol.84","No.12","1393","1397","eng","true","null","scientific_journal","null","null","10.1016/j.vacuum.2010.01.006","0042-207X","null","null","null","null","null"
"Effects of Capacitively Coupled Radio Frequency Krypton and Argon Plasmas on Gallium Nitride Etching Damage","Effects of Capacitively Coupled Radio Frequency Krypton and Argon Plasmas on Gallium Nitride Etching Damage","Retsuo Kawakami, Takeshi Inaoka, Kikuo Tominaga, Mukai Takashi","Retsuo Kawakami, Takeshi Inaoka, Kikuo Tominaga, Mukai Takashi","null","GaN etching damage characteristics by capacitively coupled radio frequency Kr and Ar plasmas have been found to differ significantly, on the basis of experimental and simulation results. The morphology of a GaN surface etched by Kr plasma is as smooth as that of the as-grown surface, and is independent of gas pressure and etching time. The agreement between the experimental and simulated etching depths for the Kr plasma, which are lower than those for the Ar plasma, indicates a significant contribution to the GaN damage of the physical etching effect. In contrast, Ar plasma etching produces a rough surface, which is dependent on gas pressure and etching time, and appears to be due to a chemical effect. The difference in the GaN surface morphologies etched by the Kr and Ar plasmas may be attributed to the different depths etched for these two plasmas. Moreover, the simulation shows that, for the Kr plasma, Ga is preferentially etched from GaN, whereas the preferential etching of N occurs for the Ar plasma. The difference in preferential etching between the Kr and Ar plasmas may be related to the difference between the GaN surface morphologies etched by these two plasmas.","GaN etching damage characteristics by capacitively coupled radio frequency Kr and Ar plasmas have been found to differ significantly, on the basis of experimental and simulation results. The morphology of a GaN surface etched by Kr plasma is as smooth as that of the as-grown surface, and is independent of gas pressure and etching time. The agreement between the experimental and simulated etching depths for the Kr plasma, which are lower than those for the Ar plasma, indicates a significant contribution to the GaN damage of the physical etching effect. In contrast, Ar plasma etching produces a rough surface, which is dependent on gas pressure and etching time, and appears to be due to a chemical effect. The difference in the GaN surface morphologies etched by the Kr and Ar plasmas may be attributed to the different depths etched for these two plasmas. Moreover, the simulation shows that, for the Kr plasma, Ga is preferentially etched from GaN, whereas the preferential etching of N occurs for the Ar plasma. The difference in preferential etching between the Kr and Ar plasmas may be related to the difference between the GaN surface morphologies etched by these two plasmas.","null","null","2009-08-10","Japanese Journal of Applied Physics, Part 1 (Regular Papers & Short Notes)","Japanese Journal of Applied Physics, Part 1 (Regular Papers & Short Notes)","Vol.48","No.8","08HF01-1","08HF01-4","eng","true","null","scientific_journal","null","null","10.1143/JJAP.48.08HF01","0021-4922","null","http://ci.nii.ac.jp/naid/150000052764/","null","null","null"
"Synergy Effect of Particle Radiation and Ultraviolet Radiation from Capacitively Coupled Radio Frequency Argon Plasmas on n-GaN Etching Damage","Synergy Effect of Particle Radiation and Ultraviolet Radiation from Capacitively Coupled Radio Frequency Argon Plasmas on n-GaN Etching Damage","Retsuo Kawakami, Inaoka Takeshi, Kuwahara Akinobu, Kikuo Tominaga, Mukai Takashi","Retsuo Kawakami, Inaoka Takeshi, Kuwahara Akinobu, Kikuo Tominaga, Mukai Takashi","null","The change in the morphology of n-GaN surfaces etched by capacitively coupled RF Ar plasmas has been studied from the viewpoint of a synergy effect of particle radiation and UV radiation from the RF plasmas. The particle radiation (in particular, the energy of Ar+ impinging on n-GaN) is intensified with decreasing gas pressure from 200 to 10 mTorr, whereas the intensity of the UV radiation (whose peak wavelength corresponds to the GaN band-gap energy) is significantly weakened. The reverse result occurs when the gas pressure increases. Each type of radiation brings about a smooth surface morphology similar to that of the as-grown surface. However, at 50 or 100 mTorr, at which both types of radiation are expected to coexist, the surface morphology shows various types of pits (defects or dislocations), which seem to be induced by the synergy effect.","The change in the morphology of n-GaN surfaces etched by capacitively coupled RF Ar plasmas has been studied from the viewpoint of a synergy effect of particle radiation and UV radiation from the RF plasmas. The particle radiation (in particular, the energy of Ar+ impinging on n-GaN) is intensified with decreasing gas pressure from 200 to 10 mTorr, whereas the intensity of the UV radiation (whose peak wavelength corresponds to the GaN band-gap energy) is significantly weakened. The reverse result occurs when the gas pressure increases. Each type of radiation brings about a smooth surface morphology similar to that of the as-grown surface. However, at 50 or 100 mTorr, at which both types of radiation are expected to coexist, the surface morphology shows various types of pits (defects or dislocations), which seem to be induced by the synergy effect.","null","null","2008-07-10","Japanese Journal of Applied Physics, Part 1 (Regular Papers & Short Notes)","Japanese Journal of Applied Physics, Part 1 (Regular Papers & Short Notes)","Vol.47","No.8","6863","6866","eng","true","null","scientific_journal","null","null","10.1143/JJAP.47.6863","0021-4922","null","http://ci.nii.ac.jp/naid/150000051237/","null","null","null"
"Effect of Argon Plasma Etching Damage on Electrical Characteristics of Gallium Nitride","Effect of Argon Plasma Etching Damage on Electrical Characteristics of Gallium Nitride","Retsuo Kawakami, Inaoka Takeshi","Retsuo Kawakami, Inaoka Takeshi","null","null","null","null","null","2008-04","Vacuum","Vacuum","Vol.83","No.3","490","492","eng","true","null","scientific_journal","null","null","10.1016/j.vacuum.2008.04.009","0042-207X","null","null","null","null","null"
"Analysis of GaN Etching Damage by Capacitively Coupled RF Ar Plasma Exposure","Analysis of GaN Etching Damage by Capacitively Coupled RF Ar Plasma Exposure","Retsuo Kawakami, Inaoka Takeshi, Minamoto Shingo, Kikuhara Yasuyuki","Retsuo Kawakami, Inaoka Takeshi, Minamoto Shingo, Kikuhara Yasuyuki","null","null","null","null","null","2008-03","Thin Solid Films","Thin Solid Films","Vol.516","No.11","3478","3481","eng","true","null","scientific_journal","null","null","10.1016/j.tsf.2007.08.019","0040-6090","null","null","null","null","null"
"Simulation Study of Carbon Impurity Dynamics on Tungsten Surfaces Exposed to Hydrogen Ions","Simulation Study of Carbon Impurity Dynamics on Tungsten Surfaces Exposed to Hydrogen Ions","Retsuo Kawakami","Retsuo Kawakami","null","null","null","null","null","2006-10","Journal of Nuclear Materials","Journal of Nuclear Materials","Vol.348","null","256","262","eng","true","null","scientific_journal","null","null","10.1016/j.jnucmat.2005.09.019","0022-3115","null","null","null","null","null"
"Simulation study of carbon impurity dynamics on reduced-activation ferritic/martensitic steel material at elevated temperatures under hydrogen exposure","Simulation study of carbon impurity dynamics on reduced-activation ferritic/martensitic steel material at elevated temperatures under hydrogen exposure","Retsuo Kawakami","Retsuo Kawakami","null","null","null","null","null","2006-04","Fusion Engineering and Design","Fusion Engineering and Design","Vol.81","No.8-14","1683","1687","eng","true","null","scientific_journal","null","null","10.1016/j.fusengdes.2005.09.009","0920-3796","null","null","null","null","null"
"Simulation Study on Effects of Chemically Eroded Methane and Ethylene Molecules on Carbon Impurity Transport and Net Erosion of Carbon Materials","Simulation Study on Effects of Chemically Eroded Methane and Ethylene Molecules on Carbon Impurity Transport and Net Erosion of Carbon Materials","Retsuo Kawakami","Retsuo Kawakami","null","null","null","null","null","2006-02-01","Journal of Plasma and Fusion Research SERIES","Journal of Plasma and Fusion Research SERIES","Vol.7","null","94","97","null","true","null","scientific_journal","null","null","null","1883-9630","null","null","null","null","null"
"Influence of Carbon Impurity on Net Erosion of Reduced-Activation Ferritic/Martensitic Steel and Tungsten Materials Exposed to Hydrogen and Carbon Mixed Ion Beam Relevant to Fusion Plasma Boundary","Influence of Carbon Impurity on Net Erosion of Reduced-Activation Ferritic/Martensitic Steel and Tungsten Materials Exposed to Hydrogen and Carbon Mixed Ion Beam Relevant to Fusion Plasma Boundary","Retsuo Kawakami, Tomohisa Shimada, Yoshio Ueda, Masahiro Nishikawa","Retsuo Kawakami, Tomohisa Shimada, Yoshio Ueda, Masahiro Nishikawa","null","Using a simulation code for dynamic interactions between energetic ions and solid materials, the influence of C impurity concentration on net erosion of reduced-activation ferritic/martensitic steel, RAF (Fe in the simulation), and W materials exposed to a 0.33 keV H+ and 1 keV C+ impurity mixed ion beam relevant to a fusion plasma boundary has been studied. A comparison of the simulation results between the Fe and W materials at C impurity concentrations less than C: 1.00% is described and discussed. In particular, emphasis is paid to a quantitative comparison between depth profiles of C impurity deposited on the materials and the experimental data, which were obtained by the H and C mixed ion beam exposure experiments of RAF (F82H in the experiment) and W materials. For the W material, chemical erosion (CH4 emission) of the deposited C impurity by the H+ impact is taken into account in the simulation. The C impurity concentration causes a significant difference in net erosion between the two materials. For the Fe material, net erosion is suppressed with increasing C impurity concentration. In contrast, for the W material, net erosion is enhanced. In the depth profile, there is also a significant difference between the two materials. At C: 0.11%, the impinging C impurity is hardly deposited on the Fe material. For the W material, the depth profile at C: 0.11% shows a local peak around a certain depth, which is in good agreement with the experimental data at 653 K. This agreement indicates no contribution of the chemical erosion in the H-C-W system, which is quite different from that in the H-C system where the chemical erosion occurs. The difference seems to indicate that the chemical erosion in the H-C-W system is dependent upon amounts of the deposited C impurity or the binary alloy phase change between W and C. When the C impurity concentration increases to C: 0.84%, the impinging C impurity is deposited on the Fe material. The depth profile shows a maximum at the top surface, which reproduces the experimental data at 453 K. For the W material, the depth profile at C: 0.84% shows almost the same tendency as that at C: 0.11%, but shows a larger amount of the deposited C impurity. The simulation result at C: 0.84% is in disagreement with the experimental result at 653 K, which shows a maximum at the top surface. This disagreement is not fully explained by only the chemical erosion.","Using a simulation code for dynamic interactions between energetic ions and solid materials, the influence of C impurity concentration on net erosion of reduced-activation ferritic/martensitic steel, RAF (Fe in the simulation), and W materials exposed to a 0.33 keV H+ and 1 keV C+ impurity mixed ion beam relevant to a fusion plasma boundary has been studied. A comparison of the simulation results between the Fe and W materials at C impurity concentrations less than C: 1.00% is described and discussed. In particular, emphasis is paid to a quantitative comparison between depth profiles of C impurity deposited on the materials and the experimental data, which were obtained by the H and C mixed ion beam exposure experiments of RAF (F82H in the experiment) and W materials. For the W material, chemical erosion (CH4 emission) of the deposited C impurity by the H+ impact is taken into account in the simulation. The C impurity concentration causes a significant difference in net erosion between the two materials. For the Fe material, net erosion is suppressed with increasing C impurity concentration. In contrast, for the W material, net erosion is enhanced. In the depth profile, there is also a significant difference between the two materials. At C: 0.11%, the impinging C impurity is hardly deposited on the Fe material. For the W material, the depth profile at C: 0.11% shows a local peak around a certain depth, which is in good agreement with the experimental data at 653 K. This agreement indicates no contribution of the chemical erosion in the H-C-W system, which is quite different from that in the H-C system where the chemical erosion occurs. The difference seems to indicate that the chemical erosion in the H-C-W system is dependent upon amounts of the deposited C impurity or the binary alloy phase change between W and C. When the C impurity concentration increases to C: 0.84%, the impinging C impurity is deposited on the Fe material. The depth profile shows a maximum at the top surface, which reproduces the experimental data at 453 K. For the W material, the depth profile at C: 0.84% shows almost the same tendency as that at C: 0.11%, but shows a larger amount of the deposited C impurity. The simulation result at C: 0.84% is in disagreement with the experimental result at 653 K, which shows a maximum at the top surface. This disagreement is not fully explained by only the chemical erosion.","null","null","2006-01-10","Japanese Journal of Applied Physics, Part 1 (Regular Papers & Short Notes)","Japanese Journal of Applied Physics, Part 1 (Regular Papers & Short Notes)","Vol.45","No.1A","221","227","eng","true","null","scientific_journal","null","null","10.1143/JJAP.45.221","0021-4922","null","http://ci.nii.ac.jp/naid/150000046246/","null","null","null"
"Simulation Study on Influence of Chemically Eroded Higher Hydrocarbons on SOL Impurity Transport and Effect of Dynamical Material Mixing on Erosion/Deposition of Tungsten Surfaces Exposed to Plasma Boundary","Simulation Study on Influence of Chemically Eroded Higher Hydrocarbons on SOL Impurity Transport and Effect of Dynamical Material Mixing on Erosion/Deposition of Tungsten Surfaces Exposed to Plasma Boundary","Retsuo Kawakami, Mitani Takenori","Retsuo Kawakami, Mitani Takenori","null","null","null","null","null","2005-04","Journal of Nuclear Materials","Journal of Nuclear Materials","Vol.337-339","null","45","49","eng","true","null","scientific_journal","null","null","10.1016/j.jnucmat.2004.08.027","0022-3115","null","null","null","null","null"
"Simulation Study on Influence of Chemically Eroded Carbon Impurity Transport on Net Sputtering Erosion of Carbon Materials Exposed to Edge Fusion Plasmas","Simulation Study on Influence of Chemically Eroded Carbon Impurity Transport on Net Sputtering Erosion of Carbon Materials Exposed to Edge Fusion Plasmas","Retsuo Kawakami","Retsuo Kawakami","null","Regarding TEXTOR and ITER-FEAT fusion devices, the net sputtering erosion rate of C targets exposed to their edge fusion plasmas has been investigated using a simulation code for plasma surface interactions, EDDY. The influence of the transport of chemically eroded CD4 molecules on the net erosion rate is presented. Emphasis is put on the difference in the simulated results between the CD4 reaction chain with e-, the CD4 reaction chain with e- plus D+, and the sticking coefficients of CDx locally returned back to the targets, which are related closely to the local redeposition, for a variety of plasma densities and temperatures. In particular, at a high density such as $10^{19}$ m-3 and low temperatures of less than 10 eV, the net erosion rate is found to be suppressed by a significant contribution of the local redeposition resulting from the charge exchange reactions of CDx with D+ if all the locally returned CDx radicals stick. For the ITER-FEAT divertor plasma, the profile of the net erosion rate along the outer vertical target is significantly changed by the C impurity concentration in the plasma, which is eroded from other wall surfaces and then transported by the plasma. For the D+ plasma exposure only, the net erosion rate is highest around the separatrix strike point. On the other hand, it is highest at the private plasma region if a few percent of the C impurity concentration is added to the D+ plasma exposure. The local redeposition resulting from the charge exchange reactions significantly suppresses the net erosion rates at these plasma regions, but does not bring about a significant change in the erosion/deposition profile along the outer vertical target.","Regarding TEXTOR and ITER-FEAT fusion devices, the net sputtering erosion rate of C targets exposed to their edge fusion plasmas has been investigated using a simulation code for plasma surface interactions, EDDY. The influence of the transport of chemically eroded CD4 molecules on the net erosion rate is presented. Emphasis is put on the difference in the simulated results between the CD4 reaction chain with e-, the CD4 reaction chain with e- plus D+, and the sticking coefficients of CDx locally returned back to the targets, which are related closely to the local redeposition, for a variety of plasma densities and temperatures. In particular, at a high density such as $10^{19}$ m-3 and low temperatures of less than 10 eV, the net erosion rate is found to be suppressed by a significant contribution of the local redeposition resulting from the charge exchange reactions of CDx with D+ if all the locally returned CDx radicals stick. For the ITER-FEAT divertor plasma, the profile of the net erosion rate along the outer vertical target is significantly changed by the C impurity concentration in the plasma, which is eroded from other wall surfaces and then transported by the plasma. For the D+ plasma exposure only, the net erosion rate is highest around the separatrix strike point. On the other hand, it is highest at the private plasma region if a few percent of the C impurity concentration is added to the D+ plasma exposure. The local redeposition resulting from the charge exchange reactions significantly suppresses the net erosion rates at these plasma regions, but does not bring about a significant change in the erosion/deposition profile along the outer vertical target.","null","null","2005-02-10","Japanese Journal of Applied Physics, Part 1 (Regular Papers & Short Notes)","Japanese Journal of Applied Physics, Part 1 (Regular Papers & Short Notes)","Vol.44","No.2","1069","1075","eng","true","null","scientific_journal","null","null","10.1143/JJAP.44.1069","0021-4922","null","http://ci.nii.ac.jp/naid/150000044532/","null","null","null"
"Carbon Behavior on Tungsten Surface after Carbon and Hydrogen Mixed Beam Irradiation","Carbon Behavior on Tungsten Surface after Carbon and Hydrogen Mixed Beam Irradiation","Tomohisa Shimada, Takahisa Funabiki, Retsuo Kawakami, Yoshio Ueda, Masahiro Nishikawa","Tomohisa Shimada, Takahisa Funabiki, Retsuo Kawakami, Yoshio Ueda, Masahiro Nishikawa","null","null","null","null","null","2004-07","Journal of Nuclear Materials","Journal of Nuclear Materials","Vol.329-333","No.0","747","751","eng","true","null","scientific_journal","null","null","10.1016/j.jnucmat.2004.04.180","0022-3115","null","null","null","null","null"
"Effects of Carbon Impurity in Fusion Plasmas on Erosion of RAF First Wall","Effects of Carbon Impurity in Fusion Plasmas on Erosion of RAF First Wall","Yoshio Ueda, Takahisa Funabiki, Tomohisa Shimada, Retsuo Kawakami, Masahiro Nishikawa","Yoshio Ueda, Takahisa Funabiki, Tomohisa Shimada, Retsuo Kawakami, Masahiro Nishikawa","null","null","null","null","null","2004-07","Journal of Nuclear Materials","Journal of Nuclear Materials","Vol.329-333","null","771","774","eng","true","null","scientific_journal","null","null","10.1016/j.jnucmat.2004.04.175","0022-3115","null","null","null","null","null"
"Simulation Study of Sputtering Erosion and Impurity Deposition on Carbon and Tungsten Surfaces Irradiated with Deuterium Plasmas Including Carbon Impurity","Simulation Study of Sputtering Erosion and Impurity Deposition on Carbon and Tungsten Surfaces Irradiated with Deuterium Plasmas Including Carbon Impurity","Takenori Mitani, Retsuo Kawakami, Shuhei Kuriu","Takenori Mitani, Retsuo Kawakami, Shuhei Kuriu","null","null","null","null","null","2004-07","Journal of Nuclear Materials","Journal of Nuclear Materials","Vol.329","No.329-333","830","835","eng","true","null","scientific_journal","null","null","10.1016/j.jnucmat.2004.04.212","0022-3115","null","null","null","null","null"
"Simulation Study of Dynamical Material Mixing on Tungsten Surfaces at Elevated Temperatures due to Hydrogen and Carbon Mixed Ion Beam Irradiation","Simulation Study of Dynamical Material Mixing on Tungsten Surfaces at Elevated Temperatures due to Hydrogen and Carbon Mixed Ion Beam Irradiation","Retsuo Kawakami, Tomohisa Shimada, Yoshio Ueda, Masahiro Nishikawa","Retsuo Kawakami, Tomohisa Shimada, Yoshio Ueda, Masahiro Nishikawa","null","null","null","null","null","2004-07","Journal of Nuclear Materials","Journal of Nuclear Materials","Vol.329-333","No.0","737","741","eng","true","null","scientific_journal","null","null","10.1016/j.jnucmat.2004.04.182","0022-3115","null","null","null","null","null"
"Temporal Evolution of Erosion/Deposition on Tungsten Surfaces Exposed to SOL Plasmas and its Impact on Plasma-Surface Interactions","Temporal Evolution of Erosion/Deposition on Tungsten Surfaces Exposed to SOL Plasmas and its Impact on Plasma-Surface Interactions","Retsuo Kawakami","Retsuo Kawakami","null","Temporal evolution of erosion/deposition on W surfaces exposed to SOL plasma composed of D+ and C4+ impurities, and its impact on plasma-surface interactions such as ion reflection and physical sputtering have been calculated. In particular, changes in the thickness of the W targets due to (i) C impurity concentration in the SOL plasma, and due to the additional contribution of (ii) chemical sputtering (CD4 emission) and (iii) thermal diffusion of C impurity deposited on the target are focused on. Changes in the depth profile of the deposited C are also considered. The calculated results have been compared qualitatively with experimental data which were obtained in TEXTOR-94. (i) Erosion of Wnear exposed close to the LCFS and deposition of C impurity on Wfar exposed far from the LCFS are reproduced by assuming different C impurity concentrations at the two targets. The deposition is due to the high C impurity concentration and the low plasma ion temperature, whereas the erosion is due to the converse reasons. However, the depth profiles are in disagreement with the measured growth of the W-C contamination layers. (ii) By the weak contribution of the chemical sputtering, the erosion of Wnear and the deposition on Wfar are also reproduced. Since the amount of the deposited C is decreased by the chemical sputtering, the depth profiles are also in disagreement with the experimental data. (iii) By the significant contribution of the thermal diffusion, the erosion/deposition at the two targets is also reproduced. In addition, the depth profiles for Wnear and Wfar, which show there is a deep penetration of the deposited C due to the thermal diffusion, are in good agreement with the experimental ones.","Temporal evolution of erosion/deposition on W surfaces exposed to SOL plasma composed of D+ and C4+ impurities, and its impact on plasma-surface interactions such as ion reflection and physical sputtering have been calculated. In particular, changes in the thickness of the W targets due to (i) C impurity concentration in the SOL plasma, and due to the additional contribution of (ii) chemical sputtering (CD4 emission) and (iii) thermal diffusion of C impurity deposited on the target are focused on. Changes in the depth profile of the deposited C are also considered. The calculated results have been compared qualitatively with experimental data which were obtained in TEXTOR-94. (i) Erosion of Wnear exposed close to the LCFS and deposition of C impurity on Wfar exposed far from the LCFS are reproduced by assuming different C impurity concentrations at the two targets. The deposition is due to the high C impurity concentration and the low plasma ion temperature, whereas the erosion is due to the converse reasons. However, the depth profiles are in disagreement with the measured growth of the W-C contamination layers. (ii) By the weak contribution of the chemical sputtering, the erosion of Wnear and the deposition on Wfar are also reproduced. Since the amount of the deposited C is decreased by the chemical sputtering, the depth profiles are also in disagreement with the experimental data. (iii) By the significant contribution of the thermal diffusion, the erosion/deposition at the two targets is also reproduced. In addition, the depth profiles for Wnear and Wfar, which show there is a deep penetration of the deposited C due to the thermal diffusion, are in good agreement with the experimental ones.","null","null","2004-02-10","Japanese Journal of Applied Physics, Part 1 (Regular Papers & Short Notes)","Japanese Journal of Applied Physics, Part 1 (Regular Papers & Short Notes)","Vol.43","No.2","785","794","eng","true","null","scientific_journal","null","null","10.1143/JJAP.43.785","0021-4922","null","http://ci.nii.ac.jp/naid/150000042695/","null","null","null"
"Dynamic Behavior of Tungsten Surfaces due to Simultaneous Impact of Hydrogen and Carbon Ion Beam","Dynamic Behavior of Tungsten Surfaces due to Simultaneous Impact of Hydrogen and Carbon Ion Beam","Retsuo Kawakami, Tomohisa Shimada, Yoshio Ueda, Masahiro Nishikawa","Retsuo Kawakami, Tomohisa Shimada, Yoshio Ueda, Masahiro Nishikawa","null","By using a simulation code for ion-solid interactions, EDDY, the dynamical behavior of W surfaces irradiated simultaneously with H+ and C+ impurity has been studied. This code models the fluence evolution of composition changes between C and W at the irradiated surface, which results from sputtering erosion and impurity deposition. The result has been described in terms of C impurity concentration in the irradiation. It has been compared with experimental data obtained by an ion beam irradiation device. In particular, the C impurity concentration has an important role in erosion/deposition at the W surface. As the C impurity concentration increases, the erosion is enhanced. As the C impurity concentration exceeds 3.00%, there is a transition from erosion to deposition which is due to the formation of a C film on the W surface. Regarding the result that the erosion changes to deposition, the simulation qualitatively reproduces the experimental results measured by X-ray photoemission spectroscopy (XPS). There is a different tendency in the fluence dependence for the different C impurity concentrations. For C:0.11%, the erosion rate increases with increasing fluence. This results from a growth of a local peak at around a depth of 20 nm in the depth profile of the deposited C. The growth is in good agreement with the experimental result, which shows that there is a strong contribution from recoil implantation of the deposited C due to a synergetic effect of the H and C impurity. For C:0.84%, there are almost the same tendencies as for C:0.11% in the erosion rate and in the depth profile. However, the growth of the local peak at around a depth of 10 nm is in disagreement with the measured one, which occurs near the surface. The disagreement appears to be attributable to the contribution of the surface segregation.","By using a simulation code for ion-solid interactions, EDDY, the dynamical behavior of W surfaces irradiated simultaneously with H+ and C+ impurity has been studied. This code models the fluence evolution of composition changes between C and W at the irradiated surface, which results from sputtering erosion and impurity deposition. The result has been described in terms of C impurity concentration in the irradiation. It has been compared with experimental data obtained by an ion beam irradiation device. In particular, the C impurity concentration has an important role in erosion/deposition at the W surface. As the C impurity concentration increases, the erosion is enhanced. As the C impurity concentration exceeds 3.00%, there is a transition from erosion to deposition which is due to the formation of a C film on the W surface. Regarding the result that the erosion changes to deposition, the simulation qualitatively reproduces the experimental results measured by X-ray photoemission spectroscopy (XPS). There is a different tendency in the fluence dependence for the different C impurity concentrations. For C:0.11%, the erosion rate increases with increasing fluence. This results from a growth of a local peak at around a depth of 20 nm in the depth profile of the deposited C. The growth is in good agreement with the experimental result, which shows that there is a strong contribution from recoil implantation of the deposited C due to a synergetic effect of the H and C impurity. For C:0.84%, there are almost the same tendencies as for C:0.11% in the erosion rate and in the depth profile. However, the growth of the local peak at around a depth of 10 nm is in disagreement with the measured one, which occurs near the surface. The disagreement appears to be attributable to the contribution of the surface segregation.","null","null","2003-12-10","Japanese Journal of Applied Physics, Part 1 (Regular Papers & Short Notes)","Japanese Journal of Applied Physics, Part 1 (Regular Papers & Short Notes)","Vol.42","No.12","7529","7535","eng","true","null","scientific_journal","null","null","10.1143/JJAP.42.7529","0021-4922","null","http://ci.nii.ac.jp/naid/150000040887/","null","null","null"
"Dynamic Behavior of Carbon Deposited on Tungsten Surface due to Carbon Ion Bombardment and Its Influence on Ion-Solid Interactions","Dynamic Behavior of Carbon Deposited on Tungsten Surface due to Carbon Ion Bombardment and Its Influence on Ion-Solid Interactions","Retsuo Kawakami, Kaoru Ohya","Retsuo Kawakami, Kaoru Ohya","null","動的プラズマ壁相互作用コードEDDYを用いて,タングステン表面への炭素イオンの照射時の表面組成と粒子放出特性の照射量依存性について,衝突ミキシングと熱拡散を考慮して研究した.低照射量では,物理スパッタ率は表面温度の上昇と共に減少するが,高照射量では逆に増加する.これは堆積Cの拡散のため混成層の顕著な成長が促進される結果と考えられる.","動的プラズマ壁相互作用コードEDDYを用いて,タングステン表面への炭素イオンの照射時の表面組成と粒子放出特性の照射量依存性について,衝突ミキシングと熱拡散を考慮して研究した.低照射量では,物理スパッタ率は表面温度の上昇と共に減少するが,高照射量では逆に増加する.これは堆積Cの拡散のため混成層の顕著な成長が促進される結果と考えられる.","null","null","2003-08-10","Japanese Journal of Applied Physics, Part 1 (Regular Papers & Short Notes)","Japanese Journal of Applied Physics, Part 1 (Regular Papers & Short Notes)","Vol.42","No.8","5259","5266","eng","true","null","scientific_journal","null","null","10.1143/JJAP.42.5259","0021-4922","null","http://ci.nii.ac.jp/naid/150000041993/","null","null","null"
"Sputtering Erosion and Redeposition at Divertor Surfaces Exposed to ITER-FEAT Edge Plasmas","Sputtering Erosion and Redeposition at Divertor Surfaces Exposed to ITER-FEAT Edge Plasmas","Retsuo Kawakami, Kaoru Ohya","Retsuo Kawakami, Kaoru Ohya","null","B2-EIRENEコードによって計算されたプラズマパラメータ分布を用いて,ITER-FEATのダイバータ部品の正味の損耗を,動的プラズマ壁相互作用コードEDDYで予測した.WドームとC垂直なターゲットへの炭素堆積が化学スパッタリングによって放出された炭化水素分子の再付着によって起こることを示した.また,内側と外側の垂直ターゲットの損耗の非対称性について議論した.","B2-EIRENEコードによって計算されたプラズマパラメータ分布を用いて,ITER-FEATのダイバータ部品の正味の損耗を,動的プラズマ壁相互作用コードEDDYで予測した.WドームとC垂直なターゲットへの炭素堆積が化学スパッタリングによって放出された炭化水素分子の再付着によって起こることを示した.また,内側と外側の垂直ターゲットの損耗の非対称性について議論した.","null","null","2003-06-10","Japanese Journal of Applied Physics, Part 1 (Regular Papers & Short Notes)","Japanese Journal of Applied Physics, Part 1 (Regular Papers & Short Notes)","Vol.42","No.6A","3623","3632","eng","true","null","scientific_journal","null","null","10.1143/JJAP.42.3623","0021-4922","null","http://ci.nii.ac.jp/naid/150000041635/","null","null","null"
"Simulation Study of Material Mixing Process on Tungsten Surfaces at Elevated Temperatures due to Boundary Plasma Exposure and Its Influence on Plasma Wall Interactions","Simulation Study of Material Mixing Process on Tungsten Surfaces at Elevated Temperatures due to Boundary Plasma Exposure and Its Influence on Plasma Wall Interactions","Retsuo Kawakami, Kaoru Ohya","Retsuo Kawakami, Kaoru Ohya","null","動的なプラズマ壁相互作用コードEDDYを用いて,プラズマに照射されたタングステンと炭素の材料混成について研究した.TEXTOR-94で観測されたW表面のW-C 混成層の変化と計算結果の比較はよく一致したことより,この変化がW表面への堆積炭素不純物の熱拡散のためであると考えられる.また,W-C混成層の化学損耗と放出されたCD4分子の輸送過程も調べた.","動的なプラズマ壁相互作用コードEDDYを用いて,プラズマに照射されたタングステンと炭素の材料混成について研究した.TEXTOR-94で観測されたW表面のW-C 混成層の変化と計算結果の比較はよく一致したことより,この変化がW表面への堆積炭素不純物の熱拡散のためであると考えられる.また,W-C混成層の化学損耗と放出されたCD4分子の輸送過程も調べた.","null","null","2003-04-10","Journal of Nuclear Materials","Journal of Nuclear Materials","Vol.313-316","null","107","111","eng","true","null","scientific_journal","null","null","10.1016/S0022-3115(02)01378-8","0022-3115","null","null","null","null","null"
"Dynamic Behavior of Sputtering of Tungsten Implanted in Carbon","Dynamic Behavior of Sputtering of Tungsten Implanted in Carbon","Kaoru Ohya, Retsuo Kawakami","Kaoru Ohya, Retsuo Kawakami","null","炭素への高粒子束タングステンイオンの照射によって起こるスパッタ率の時間的な振動現象について,動的シミュレーションコードを用いて研究した.低原子番号材料に注入された高原子番号粒子の深さ分布の変化に起因する現象であり,材料温度による深さ分布の変化の影響についても調べた.","炭素への高粒子束タングステンイオンの照射によって起こるスパッタ率の時間的な振動現象について,動的シミュレーションコードを用いて研究した.低原子番号材料に注入された高原子番号粒子の深さ分布の変化に起因する現象であり,材料温度による深さ分布の変化の影響についても調べた.","null","null","2001-12-01","Japanese Journal of Applied Physics, Part 1 (Regular Papers & Short Notes)","Japanese Journal of Applied Physics, Part 1 (Regular Papers & Short Notes)","Vol.40","No.12","6965","6971","null","true","null","scientific_journal","null","null","10.1143/JJAP.40.6965","1347-4065","null","null","null","null","null"
"Computer Simulation Study on Incident Fluence Dependence of Ion Reflection and Sputtering Processes from Layered and Mixed Materials","Computer Simulation Study on Incident Fluence Dependence of Ion Reflection and Sputtering Processes from Layered and Mixed Materials","Retsuo Kawakami, Kaoru Ohya","Retsuo Kawakami, Kaoru Ohya","null","炭素(C)バルクとタングステン(W)上に堆積した炭素層,C上に堆積したW層とWxC1-x混合材料上のW層について,Dイオン反射とスパッタリングの照射量依存性を動的プラズマ壁相互作用コードEDDYを用いて研究した.層状材料において,反射率とスパッタ率の照射量による変化は層の厚さに依存する.Cのスパッタ率は照射ともに減少するが,D反射率とWのスパッタ率は増加する.","炭素(C)バルクとタングステン(W)上に堆積した炭素層,C上に堆積したW層とWxC1-x混合材料上のW層について,Dイオン反射とスパッタリングの照射量依存性を動的プラズマ壁相互作用コードEDDYを用いて研究した.層状材料において,反射率とスパッタ率の照射量による変化は層の厚さに依存する.Cのスパッタ率は照射ともに減少するが,D反射率とWのスパッタ率は増加する.","null","null","2001-11-01","Japanese Journal of Applied Physics, Part 1 (Regular Papers & Short Notes)","Japanese Journal of Applied Physics, Part 1 (Regular Papers & Short Notes)","Vol.40","No.11","6581","6588","null","true","null","scientific_journal","null","null","null","0021-4922","null","null","null","null","null"
"Simulation Study on Erosion and Redeposition at Tungsten Surface Exposed to Deuterium Plasma Including Carbon Impurity","Simulation Study on Erosion and Redeposition at Tungsten Surface Exposed to Deuterium Plasma Including Carbon Impurity","Retsuo Kawakami, Kaoru Ohya","Retsuo Kawakami, Kaoru Ohya","null","炭素不純物を含む重水素プラズマに晒されたタングステン表面の損耗と再堆積を動的プラズマ表面相互作用コードEDDYを用いて研究した.計算結果を実験データ(TEXTOR-94プラズマ照射後のW試験リミタの端部におけるC堆積領域の明瞭な境界)と比較した.明瞭な境界は,プラズマ中の不純物炭素濃度と端部の低いプラズマ温度に関係し,照射量の増加とともに形成される.","炭素不純物を含む重水素プラズマに晒されたタングステン表面の損耗と再堆積を動的プラズマ表面相互作用コードEDDYを用いて研究した.計算結果を実験データ(TEXTOR-94プラズマ照射後のW試験リミタの端部におけるC堆積領域の明瞭な境界)と比較した.明瞭な境界は,プラズマ中の不純物炭素濃度と端部の低いプラズマ温度に関係し,照射量の増加とともに形成される.","null","null","2001-09-01","Journal of Plasma and Fusion Research","Journal of Plasma and Fusion Research","Vol.77","No.9","894","902","null","true","null","scientific_journal","null","null","null","null","null","null","null","null","null"
"Comparison between Static and Dynamic Simulations of Ion Reflection and Sputtering from Layered Materials","Comparison between Static and Dynamic Simulations of Ion Reflection and Sputtering from Layered Materials","Retsuo Kawakami, Kaoru Ohya","Retsuo Kawakami, Kaoru Ohya","null","動的プラズマ壁相互作用コードEDDYを用いて,低イオン照射量と高イオン照射量における二層材料のイオン反射とスパッタリングの違いを研究した.低照射量では,上層の厚さの増加によってそれらは急激に変化するが,高照射量では,上層の大きい損耗とリコイルインプランテーションの効果によりゆるやかな変化を示す.","動的プラズマ壁相互作用コードEDDYを用いて,低イオン照射量と高イオン照射量における二層材料のイオン反射とスパッタリングの違いを研究した.低照射量では,上層の厚さの増加によってそれらは急激に変化するが,高照射量では,上層の大きい損耗とリコイルインプランテーションの効果によりゆるやかな変化を示す.","null","null","2001-09-01","Japanese Journal of Applied Physics, Part 1 (Regular Papers & Short Notes)","Japanese Journal of Applied Physics, Part 1 (Regular Papers & Short Notes)","Vol.40","No.9A","5399","5406","null","true","null","scientific_journal","null","null","null","0021-4922","null","null","null","null","null"
"A Modified EDDY Code to Simulate Erosion/Redeposition of Carbon Target in an ITER-FEAT Divertor","A Modified EDDY Code to Simulate Erosion/Redeposition of Carbon Target in an ITER-FEAT Divertor","Kaoru Ohya, Retsuo Kawakami","Kaoru Ohya, Retsuo Kawakami","null","核融合装置内のプラズマ壁相互作用の解析のため開発しているEDDY計算機シミュレーションコードに化学スパッタリングによる壁材料の損耗と放出炭化水素分子のプラズマ中の原子分子過程を追加した.炭化水素分子の再付着も考慮した正味の損耗量を評価できるようになり,ITER-FEATのダイバータ黒鉛ターゲットの損耗分布の評価を行った.","核融合装置内のプラズマ壁相互作用の解析のため開発しているEDDY計算機シミュレーションコードに化学スパッタリングによる壁材料の損耗と放出炭化水素分子のプラズマ中の原子分子過程を追加した.炭化水素分子の再付着も考慮した正味の損耗量を評価できるようになり,ITER-FEATのダイバータ黒鉛ターゲットの損耗分布の評価を行った.","null","null","2001-09-01","Japanese Journal of Applied Physics, Part 1 (Regular Papers & Short Notes)","Japanese Journal of Applied Physics, Part 1 (Regular Papers & Short Notes)","Vol.40","No.9A","5424","5430","null","true","null","scientific_journal","null","null","10.1143/JJAP.40.5424","1347-4065","null","null","null","null","null"
"Simulation calculations of mutual contamination between tungsten and carbon and its impact on plasma surface interactions","Simulation calculations of mutual contamination between tungsten and carbon and its impact on plasma surface interactions","Kaoru Ohya, Retsuo Kawakami, Tetsuo Tanabe, Motoi Wada, Tadashi Ohgo, Volker Philipps, Albrecht Pospieszczyk, Alexander Huber, Marek Rubel, Genadij Sergienko, Nobuaki Noda","Kaoru Ohya, Retsuo Kawakami, Tetsuo Tanabe, Motoi Wada, Tadashi Ohgo, Volker Philipps, Albrecht Pospieszczyk, Alexander Huber, Marek Rubel, Genadij Sergienko, Nobuaki Noda","null","TEXTOR-94トカマクの周辺プラズマに挿入したタングステン·炭素ツイン試験リミタ近傍の不純物発光分布を実機条件でのEDDYコード計算と比較した.特に,タングステンと炭素材を核融合炉内で併用した場合の相互汚染の進展とプラズマ壁相互作用への影響について研究した.","TEXTOR-94トカマクの周辺プラズマに挿入したタングステン·炭素ツイン試験リミタ近傍の不純物発光分布を実機条件でのEDDYコード計算と比較した.特に,タングステンと炭素材を核融合炉内で併用した場合の相互汚染の進展とプラズマ壁相互作用への影響について研究した.","null","null","2001-03-01","Journal of Nuclear Materials","Journal of Nuclear Materials","Vol.290-293","null","303","307","null","true","null","scientific_journal","null","null","10.1016/S0022-3115(00)00632-2","0022-3115","null","null","null","null","null"
"Simulation Study on Influence of Mutual Contamination on Ion Reflection and Sputtering from Tungsten and Carbon Materials","Simulation Study on Influence of Mutual Contamination on Ion Reflection and Sputtering from Tungsten and Carbon Materials","Retsuo Kawakami, Nobuyasu Saji, Kaoru Ohya","Retsuo Kawakami, Nobuyasu Saji, Kaoru Ohya","null","動的プラズマ壁相互作用EDDYコードを用いて,ダイバータ内でタングステンと炭素を同時に使用したときの相互汚染について研究した.W上に堆積したC堆積はWのイオン反射率とスパッタ率を減少させる一方,C上に堆積したW堆積は,逆に反射率を増加し,させて,Cのスパッタリングを減少させる.","動的プラズマ壁相互作用EDDYコードを用いて,ダイバータ内でタングステンと炭素を同時に使用したときの相互汚染について研究した.W上に堆積したC堆積はWのイオン反射率とスパッタ率を減少させる一方,C上に堆積したW堆積は,逆に反射率を増加し,させて,Cのスパッタリングを減少させる.","null","null","2000-12-01","Journal of Plasma and Fusion Research SERIES","Journal of Plasma and Fusion Research SERIES","Vol.3","null","332","336","null","true","null","scientific_journal","null","null","null","null","null","null","null","null","null"
"Time Evolution of Surface Topography of Plasma Facing Materials with Non-Uniform Impurity Deposition","Time Evolution of Surface Topography of Plasma Facing Materials with Non-Uniform Impurity Deposition","Kaoru Ohya, Retsuo Kawakami, Hiroshi Aizawa","Kaoru Ohya, Retsuo Kawakami, Hiroshi Aizawa","null","高粒子束プラズマに照射された材料の表面凹凸の時間発展を計算するシミュレーションコードを開発した.表面にプラズマ炭素不純物が正弦波状に堆積したボロン被膜の表面変化の計算に適用し,炭素の非一様な堆積によって表面の平均的損耗が大きく変化することを示した.","高粒子束プラズマに照射された材料の表面凹凸の時間発展を計算するシミュレーションコードを開発した.表面にプラズマ炭素不純物が正弦波状に堆積したボロン被膜の表面変化の計算に適用し,炭素の非一様な堆積によって表面の平均的損耗が大きく変化することを示した.","null","null","2000-12-01","Journal of Plasma and Fusion Research, SERIES","Journal of Plasma and Fusion Research, SERIES","null","No.3","288","292","null","true","null","scientific_journal","null","null","null","null","null","null","null","null","null"
"Simulation study of carbon and tungsten deposition on W/C twin test limiter in TEXTOR-94","Simulation study of carbon and tungsten deposition on W/C twin test limiter in TEXTOR-94","Kaoru Ohya, Retsuo Kawakami, Tetsuo Tanabe, Motoi Wada, Tadashi Ohgo, Volker Philipps, Albrecht Pospieszczyk, Bernd Schweer, Alexander Huber, Marek Rubel, Jana Seggern von, Nobuaki Noda","Kaoru Ohya, Retsuo Kawakami, Tetsuo Tanabe, Motoi Wada, Tadashi Ohgo, Volker Philipps, Albrecht Pospieszczyk, Bernd Schweer, Alexander Huber, Marek Rubel, Jana Seggern von, Nobuaki Noda","null","タングステンと炭素で構成した試験リミタをTEXTOR-94トカマクの周辺プラズマに晒した時のリミタの不純物放出と表面変化について,動的プラズマ壁相互作用コードEDDYを用いて研究した.実験で観測されたリミタのW側のWI発光分布はWの物理スパッタリング,CII発光分布はCイオンの反射と再堆積Cの物理スパッタリングによって説明できた.","タングステンと炭素で構成した試験リミタをTEXTOR-94トカマクの周辺プラズマに晒した時のリミタの不純物放出と表面変化について,動的プラズマ壁相互作用コードEDDYを用いて研究した.実験で観測されたリミタのW側のWI発光分布はWの物理スパッタリング,CII発光分布はCイオンの反射と再堆積Cの物理スパッタリングによって説明できた.","null","null","2000-12-01","Journal of Nuclear Materials","Journal of Nuclear Materials","Vol.283-287","null","1182","1186","null","true","null","scientific_journal","null","null","null","0022-3115","null","null","null","null","null"
"Study of Impurity Release from a W-C Twin Test Limiter Exposed to TEXTOR-94","Study of Impurity Release from a W-C Twin Test Limiter Exposed to TEXTOR-94","Retsuo Kawakami, Nobuyasu Saji, Kaoru Ohya","Retsuo Kawakami, Nobuyasu Saji, Kaoru Ohya","null","null","null","null","null","2000-03-01","Bulletin of Faculty of Engineering, The University of Tokushima","Bulletin of Faculty of Engineering, The University of Tokushima","null","No.45","75","83","null","true","null","scientific_journal","null","null","null","0371-5949","null","null","null","null","null"
"Calculation of Impurity Release from Walls and its Transport in Edge Plasmas","Calculation of Impurity Release from Walls and its Transport in Edge Plasmas","Retsuo Kawakami, Kaoru Ohya, Jun Kawata","Retsuo Kawakami, Kaoru Ohya, Jun Kawata","null","プラズマ壁相互作用コードEDDYを用いて相互汚染下での(つまりW上にCが堆積,またはC上にWが堆積)WとCの相互汚染下での損耗と不純物再堆積過程を研究した.スパッタ炭素原子の再堆積はW表面の損耗率の低下を引き起こし,C(W)表面に堆積したW(C)は実質的にはDと不純物イオンの反射係数を増加(わずかに減少)させる.","プラズマ壁相互作用コードEDDYを用いて相互汚染下での(つまりW上にCが堆積,またはC上にWが堆積)WとCの相互汚染下での損耗と不純物再堆積過程を研究した.スパッタ炭素原子の再堆積はW表面の損耗率の低下を引き起こし,C(W)表面に堆積したW(C)は実質的にはDと不純物イオンの反射係数を増加(わずかに減少)させる.","null","null","2000-01-01","Contributions to Plasma Physics","Contributions to Plasma Physics","Vol.40","No.3","519","524","null","true","null","scientific_journal","null","null","10.1002/1521-3986(200006)40:3/4<519::AID-CTPP519>3.0.CO;2-I","1521-3986","null","null","null","null","null"
"Anomalous Relaxation and Stopping Power for Electron Beam in Beam-Plasma System","Anomalous Relaxation and Stopping Power for Electron Beam in Beam-Plasma System","Kazumasa Hara, Ichiro Mori, Retsuo Kawakami, Kikuo Tominaga","Kazumasa Hara, Ichiro Mori, Retsuo Kawakami, Kikuo Tominaga","null","ビームプラズマ放電において,電子ビームはソリトンを放射するが,そのとき特異な緩和や電子素子能をしめすことが理論的に解析されている.計算結果は実験と比較されている.ビーム電子がイオン波の急峻な負の波面,すなわち,減速場,に衝突するときソリトンを放射する.これはコヒーレントな相互作用を介しておこなわれる.","ビームプラズマ放電において,電子ビームはソリトンを放射するが,そのとき特異な緩和や電子素子能をしめすことが理論的に解析されている.計算結果は実験と比較されている.ビーム電子がイオン波の急峻な負の波面,すなわち,減速場,に衝突するときソリトンを放射する.これはコヒーレントな相互作用を介しておこなわれる.","null","null","1999-12-01","Journal of Plasma and Fusion Research SERIES","Journal of Plasma and Fusion Research SERIES","Vol.2","null","376","380","null","true","null","scientific_journal","null","null","null","null","null","null","null","null","null"
"Nonlinear Dispersion Relation for Beam-Excited Plasma","Nonlinear Dispersion Relation for Beam-Excited Plasma","Makoto Ogawa, Ichiro Mori, Retsuo Kawakami, Kikuo Tominaga","Makoto Ogawa, Ichiro Mori, Retsuo Kawakami, Kikuo Tominaga","null","ビームプラズマ放電における崩落ソリトンの発生について実験的に研究史,それに対する非線形理論と分散関係について調べた.ガウス型グリーン関数を用いて非線形分散関係を得ることに成功した.さらに,この非線形分散関係を数値的に解くことを試みた.結果として,ωーk面に2つの曲線が得られ,これらが電子ビームの分散である.これらの曲線は線形の分散から導かれる解に非常によく似ている.","ビームプラズマ放電における崩落ソリトンの発生について実験的に研究史,それに対する非線形理論と分散関係について調べた.ガウス型グリーン関数を用いて非線形分散関係を得ることに成功した.さらに,この非線形分散関係を数値的に解くことを試みた.結果として,ωーk面に2つの曲線が得られ,これらが電子ビームの分散である.これらの曲線は線形の分散から導かれる解に非常によく似ている.","null","null","1999-12-01","Journal of Plasma and Fusion Research SERIES","Journal of Plasma and Fusion Research SERIES","Vol.2","null","371","375","null","true","null","scientific_journal","null","null","null","null","null","null","null","null","null"
"Structure of Multi-dimensional Soliton and Generation of Caviton in the Nonlinear Beam-Plasma System","Structure of Multi-dimensional Soliton and Generation of Caviton in the Nonlinear Beam-Plasma System","Ichiro Mori, Toshifumi Morimoto, Retsuo Kawakami, Kikuo Tominaga","Ichiro Mori, Toshifumi Morimoto, Retsuo Kawakami, Kikuo Tominaga","null","ソリトンとキャビトンの生成機構に関する実験結果を解析した.ソリトンが発生する際には,イオン花見(キャビトン)を伴っている.ガウス関数型グリーン関数に関して,繰り込み理論によって電子ビームによって作られる孤立波を描いた.すなわち,電子同士がフォノンを介してコヒーレントな相互作用をすることでソリトンを放射する.","ソリトンとキャビトンの生成機構に関する実験結果を解析した.ソリトンが発生する際には,イオン花見(キャビトン)を伴っている.ガウス関数型グリーン関数に関して,繰り込み理論によって電子ビームによって作られる孤立波を描いた.すなわち,電子同士がフォノンを介してコヒーレントな相互作用をすることでソリトンを放射する.","null","null","1999-12-01","Journal of Plasma and Fusion Research SERIES","Journal of Plasma and Fusion Research SERIES","Vol.2","null","363","367","null","true","null","scientific_journal","null","null","null","null","null","null","null","null","null"
"Nonlinear Waves Observed in an Electron Beam-Plasma","Nonlinear Waves Observed in an Electron Beam-Plasma","Retsuo Kawakami, Ichiro Mori, Toshifumi Morimoto","Retsuo Kawakami, Ichiro Mori, Toshifumi Morimoto","null","null","null","null","null","1999-12-01","Journal of Plasma and Fusion Research SERIES","Journal of Plasma and Fusion Research SERIES","Vol.2","null","368","370","null","true","null","scientific_journal","null","null","null","null","null","null","null","null","null"
"Simultaneous Calculation of Reflection, Physical Sputtering and Secondary Electron Emission from a Metal Surface Due to Impact of Low-Energy Ions","Simultaneous Calculation of Reflection, Physical Sputtering and Secondary Electron Emission from a Metal Surface Due to Impact of Low-Energy Ions","Retsuo Kawakami, Jun Kawata, Kaoru Ohya","Retsuo Kawakami, Jun Kawata, Kaoru Ohya","null","アルミニウム中での10eVから10keVの低エネルギーイオン(原子番号1から17)の弾性,非弾性衝突過程を同時に取り扱う計算機シミュレーションコードを開発した.そのコードは励起電子の電子カスケードと反跳原子の衝突カスケードの計算を行い,固体からのイオン反射,物理スパッタリング,二次電子放出の計算ができる.","アルミニウム中での10eVから10keVの低エネルギーイオン(原子番号1から17)の弾性,非弾性衝突過程を同時に取り扱う計算機シミュレーションコードを開発した.そのコードは励起電子の電子カスケードと反跳原子の衝突カスケードの計算を行い,固体からのイオン反射,物理スパッタリング,二次電子放出の計算ができる.","null","null","1999-10-01","Japanese Journal of Applied Physics, Part 1 (Regular Papers & Short Notes)","Japanese Journal of Applied Physics, Part 1 (Regular Papers & Short Notes)","Vol.38","No.10","6058","6065","null","true","null","scientific_journal","null","null","null","0021-4922","null","null","null","null","null"
"Anomalous Electronic stopping and relaxation in the plasma and application of its theory to beam-surface interaction","Anomalous Electronic stopping and relaxation in the plasma and application of its theory to beam-surface interaction","Ichiro Mori, Toshifumi Morimoto, Retsuo Kawakami, Kikuo Tominaga","Ichiro Mori, Toshifumi Morimoto, Retsuo Kawakami, Kikuo Tominaga","null","電子ビームをガスプラズマに注入した場合の電子的青銅機構の新しい理論を提案し,高速家電粒子と固体表面のコヒーレントな相互作用理論に適用した.実験はミラー磁界を持つビームプラズマ装置でおこなった.電子ビームがアルゴンガスを電離させるような電子ビームプラズマ系を考える場合,電子励起を伴う非弾性散乱による電子的素子能をけいさんした.ビームのエネルギーの緩和が観測されたが,これは理論の予測とよく一致する.","電子ビームをガスプラズマに注入した場合の電子的青銅機構の新しい理論を提案し,高速家電粒子と固体表面のコヒーレントな相互作用理論に適用した.実験はミラー磁界を持つビームプラズマ装置でおこなった.電子ビームがアルゴンガスを電離させるような電子ビームプラズマ系を考える場合,電子励起を伴う非弾性散乱による電子的素子能をけいさんした.ビームのエネルギーの緩和が観測されたが,これは理論の予測とよく一致する.","null","null","1999-06-01","Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms","Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms","Vol.153","No.1-4","31","35","null","true","null","scientific_journal","null","null","10.1016/S0168-583X(99)00206-2","0168-583X","null","null","null","null","null"
"Cascade Collision of Fe-Atom Caused by Low Energy He-Incidence and Effect of Temperature to the Type of Defect","Cascade Collision of Fe-Atom Caused by Low Energy He-Incidence and Effect of Temperature to the Type of Defect","Ichiro Mori, Toshifumi Morimoto, Retsuo Kawakami, Kikuo Tominaga","Ichiro Mori, Toshifumi Morimoto, Retsuo Kawakami, Kikuo Tominaga","null","分子運動力学モデルシミュレーション法によって低エネルギーヘリウム原子が体心立方格子の鉄結晶に注入されたときにフォーカシングカスケード衝突が観測された.また,格子温度と欠陥の型が関連していることについて議論した.ヘリウム原子と鉄原子の質量比が大きいにもかかわらず,非常に小さいエネルギーで格子欠陥が生ずることを示した.","分子運動力学モデルシミュレーション法によって低エネルギーヘリウム原子が体心立方格子の鉄結晶に注入されたときにフォーカシングカスケード衝突が観測された.また,格子温度と欠陥の型が関連していることについて議論した.ヘリウム原子と鉄原子の質量比が大きいにもかかわらず,非常に小さいエネルギーで格子欠陥が生ずることを示した.","null","null","1999-06-01","Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms","Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms","Vol.153","No.1-4","126","129","null","true","null","scientific_journal","null","null","10.1016/S0168-583X(99)00210-4","0168-583X","null","null","null","null","null"
"Monte Carlo Simulation of Ion Reflection, Physical Sputtering and Kinetic Electron Emission from Solid Due to Ion Impact","Monte Carlo Simulation of Ion Reflection, Physical Sputtering and Kinetic Electron Emission from Solid Due to Ion Impact","Kawata Jun, Ohya Kaoru, Retsuo Kawakami","Kawata Jun, Ohya Kaoru, Retsuo Kawakami","null","null","null","null","null","1999-05-01","Bulletin of Takuma National College of Technology","Bulletin of Takuma National College of Technology","null","No.27","73","88","null","true","null","scientific_journal","null","null","null","null","null","null","null","null","null"
"Variation of Ion Transport Properties under Electric Field with Mass Ratios","Variation of Ion Transport Properties under Electric Field with Mass Ratios","Takafumi Miyazaki, Retsuo Kawakami, Nobuaki Ikuta","Takafumi Miyazaki, Retsuo Kawakami, Nobuaki Ikuta","null","null","null","null","null","1998-04-01","Journal of the Physical Society of Japan","Journal of the Physical Society of Japan","Vol.67","No.4","1260","1272","null","true","null","scientific_journal","null","null","null","0031-9015","null","null","null","null","null"
"Variation of Reduced Mobilities of Ions in Gases under 12-4 Potentials","Variation of Reduced Mobilities of Ions in Gases under 12-4 Potentials","Retsuo Kawakami, Shinya Okuda, Takafumi Miyazaki, Nobuaki Ikuta","Retsuo Kawakami, Shinya Okuda, Takafumi Miyazaki, Nobuaki Ikuta","null","null","null","null","null","1996-01-01","Journal of the Physical Society of Japan","Journal of the Physical Society of Japan","Vol.65","No.5","1270","1276","null","true","null","scientific_journal","null","null","null","0031-9015","null","null","null","null","null"
"Ion Transport Properties in Model Gases Based on A dot r^{-n} Type Single Potential","Ion Transport Properties in Model Gases Based on A dot r^{-n} Type Single Potential","Shinya Okuda, Takafumi Miyazaki, Retsuo Kawakami, Nobuaki Ikuta","Shinya Okuda, Takafumi Miyazaki, Retsuo Kawakami, Nobuaki Ikuta","null","null","null","null","null","1995-01-01","Journal of the Physical Society of Japan","Journal of the Physical Society of Japan","Vol.64","No.8","2868","2885","null","true","null","scientific_journal","null","null","null","0031-9015","null","null","null","null","null"