Search Results:  1-20 of 435

  • 1

    High nitrogen pressure solution growth of GaN

    Bockowski Michal

    … A new approach of seeded growth, multi-feed seed (MFS) configuration, is demonstrated. … The use of two kinds of seeds: free-standing hydride vapor phase epitaxy GaN (HVPE-GaN) obtained from metal organic chemical vapor deposition (MOCVD)-GaN/sapphire templates and free-standing HVPE-GaN obtained from the ammonothermally grown GaN crystals, is shown. … The role and influence of impurities, like oxygen and magnesium, on GaN crystals grown from gallium solution in the MFS configuration is presented. …

    Jpn. J. Appl. Phys. 53(10), 100203, 2014-09-08

    JSAP

  • 2

    Growth of bulk GaN crystals by the Na-flux point seed technique

    Imade Mamoru , Maruyama Mihoko , Yoshimura Masashi , Mori Yusuke

    Jpn. J. Appl. Phys. 53(5S1), 05FA06, 2014-04-15

    JSAP

  • 4

    Metal--Organic Vapor Phase Epitaxy Growth of Embedded Gallium Nitride Nanocolumn for Reduction in Dislocation Density

    Umeda Shinya , Kato Takahiro , Kitano Tsukasa , Kondo Toshiyuki , Matsubara Hiroyuki , Kamiyama Satoshi , Takeuchi Tetsuya , Iwaya Motoaki , Akasaki Isamu

    … The use of nanocolumn crystals is thought to be effective in producing a low-dislocation-density GaN layers. …

    Jpn J Appl Phys 52(8), 08JE23-08JE23-4, 2013-08-25

    JSAP

  • 5

    Effects of Solution Stirring on the Growth of Bulk GaN Single Crystals by Na Flux Method

    Murakami Kousuke , Matsuo Daisuke , Imabayashi Hiroki , Takazawa Hideo , Todoroki Yuma , Kitamoto Akira , Maruyama Mihoko , Imade Mamoru , Yoshimura Masashi , Mori Yusuke

    … Recently, we succeeded in fabricating centimeter-sized bulk gallium nitride (GaN) crystals with large dislocation-free areas on a GaN point seed. … We conclude that solution stirring may be an effective technique for fabricating high-quality large bulk GaN crystals. …

    Jpn J Appl Phys 52(8), 08JA03-08JA03-4, 2013-08-25

    JSAP

  • 6

    High Quality, Low Cost Ammonothermal Bulk GaN Substrates

    Ehrentraut Dirk , Pakalapati Rajeev T. , Kamber Derrick S. , Jiang Wenkan , Pocius Douglas W. , Downey Bradley C. , McLaurin Melvin , D'Evelyn Mark P.

    … Ammonothermal GaN growth using a novel apparatus has been performed on c-plane, m-plane, and semipolar seed crystals with diameters between 5 mm and 2 in. … The crystals have been characterized by X-ray diffraction rocking-curve (XRC) analysis, optical and scanning electron microscopy (SEM), cathodoluminescence (CL), optical spectroscopy, and capacitance--voltage measurements. …

    Jpn J Appl Phys 52(8), 08JA01-08JA01-4, 2013-08-25

    JSAP

  • 7

    Preparation of Free-Standing GaN Substrates from Thick GaN Layers Crystallized by Hydride Vapor Phase Epitaxy on Ammonothermally Grown GaN Seeds

    Sochacki Tomasz , Bryan Zachary , Amilusik Mikolaj , Collazo Ramon , Lucznik Boleslaw , Weyher Jan L. , Nowak Grzegorz , Sadovyi Bogdan , Kamler Grzegorz , Kucharski Robert , Zajac Marcin , Doradzinski Roman , Dwilinski Robert , Grzegory Izabella , Bockowski Michal , Sitar Zlatko

    … Crystallization of GaN by hydride vapor phase epitaxy (HVPE) on ammonothermally grown GaN seed crystals is described. …

    Applied Physics Express 6(7), 075504-075504-4, 2013-07-25

    JSAP

  • 8

    Mechanical stimulation and solid seeding trigger single-crystal-to-single-crystal molecular domino transformations

    Ito Hajime , Muromoto Mai , Kurenuma Sayaka , Ishizaka Shoji , Kitamura Noboru , Sato Hiroyasu , Seki Tomohiro

    … Numerous studies have focused on the mechanical control of solid structures and phase changes in molecular crystals. … The phase transformation initiates at the location of the mechanical stimulation or seed crystal, extends to adjacent crystals, and can be readily monitored visually by the accompanying photoluminescent colour change from blue to yellow. …

    Nature communications 4, 2013-06

    IR CrossRef

  • 9

    Effect of the Inclusion of Transparency on the Thermal Field and Interface Shape in Long-term Sublimation Growth of SiC Crystals(<Special Issue>)Opening Up a New World of Crystal Growth on SiC)

    Gao Bing , Kakimoto Koichi

    … To determine if the transparency of SiC crystals affects the crystal growth during long-term sublimation growth and the difference between the results with and without the inclusion of transparency, a global solver that considers almost all of the effects in the heat and mass transport processes, such as the compressible effect, the convection effect, the buoyancy effect, flow coupling of argon gas and species, and the Stefan effect, was developed. …

    Journal of the Japanese Association of Crystal Growth 40(1), 20-24, 2013-04

    CiNii Fulltext PDF - Subscription 

  • 10

    High Pressure Synthesis of Defect-free Single Crystal Diamond(<Special Issue>Diamond Growth)  [in Japanese]

    Sumiya Hitoshi

    高圧高温下(HPHT)での温度差法において,高純度な炭素源とFe-Co-Ti溶媒,高結晶性の(001)種結晶を用い,HPHT条件を高精度に制御して,最大径12mmの高品質IIa型単結晶ダイヤモンドを合成した.このダイヤモンドは,天然あるいは従来の合成のダイヤモンドに比べて欠陥密度がはるかに少なく,非常に高い結晶性を有する.特に,(001)種結晶に成長させた結晶の種結晶上部の(001)成長セクター内 …

    Journal of the Japanese Association of Crystal Growth 39(4), 164-169, 2013-01

    CiNii Fulltext PDF - Subscription 

  • 11

    Hydrothermal transformation of magnetically orientation-controlled seed layer into orientation-retained dense, continuous film in clear reaction solution

    MATSUNAGA Chika , UCHIKOSHI Tetsuo , SUZUKI Tohru S. , SAKKA Yoshio , MATSUDA Motohide

    … Randomly-oriented and b-axis oriented mordenite seed layers, which were pre-fabricated out of and in a strong 12 T magnetic field, were hydrothermally treated in clear reaction solutions with molar ratios of 6Na2O:Al2O3:30SiO2:xH2O (x = 1500, 3500 and 10000). … Crystal growth of the seed particles only slightly occurred in the solution of x = 10000, but occurred in the solutions of x = 1500 and 3500, giving rise to densified films. …

    Journal of the Ceramic Society of Japan 121(1415), 550-554, 2013

    J-STAGE CrossRef

  • 12

    The Effect of Morphology of Crystals in Suspension on Scale Formation Dynamics in Cooling Crystallization for Organic Compound

    Kudo Shoji , Hino Tomomichi , Takiyama Hiroshi

    … In the present study, the effect of the morphology of suspended crystals on scale formation dynamics (especially the transition speed of scale formation process) during start-up operation is investigated experimentally in melt crystallization for organic compounds. … Scale formation dynamics are investigated using two kinds of seed crystals of different morphologies. …

    JOURNAL OF CHEMICAL ENGINEERING OF JAPAN 46(11), 790-793, 2013

    J-STAGE CrossRef

  • 13

    Phosphorus Removal by Crystallization for Scallop Shell Adsorbent  [in Japanese]

    YOSHIMURA Kohei , SHIOMI Haruhisa

    … It was concluded that the phosphorus removal would proceed through the precipitation of DCPD seed crystals and its growth on the surface of scallop shell. …

    Journal of the Society of Materials Science, Japan 62(6), 373-376, 2013

    J-STAGE CrossRef

  • 14

    Synthesis of Au Nanorods by Using Gamma-ray Irradiation

    Okamoto Akihiko , Nagata Koichiro , Taguchi Noboru , Iwase Akihiro , Hori Fuminobu

    … To synthesize Au nanorods without the use of seed crystals, we applied gamma-ray irradiation from 60Co radioactive source to reduce aqueous solution containing Au ions. …

    Jpn J Appl Phys 51(11), 11PH01-11PH01-3, 2012-11-25

    JSAP

  • 15

    High-Efficiency Conversion of Threading Screw Dislocations in 4H-SiC by Solution Growth

    Yamamoto Yuji , Harada Shunta , Seki Kazuaki , Horio Atsushi , Mitsuhashi Takato , Ujihara Toru

    … The high-efficiency conversion of threading screw dislocations (TSDs) in 4H-SiC by solution growth provides an efficient method of obtaining ultra high-quality SiC crystals. … The behavior of TSDs on on-axis and off-axis 4H-SiC{0001} seed crystals was investigated by synchrotron X-ray topography. … Almost all TSDs in the off-axis Si-face seed crystal were converted to Frank-type stacking faults on the basal planes. …

    Applied Physics Express 5(11), 115501-115501-3, 2012-11-25

    JSAP References (24)

  • 16

    Coalescence Growth of Dislocation-Free GaN Crystals by the Na-Flux Method

    Imanishi Masayuki , Murakami Kosuke , Imabayashi Hiroki , Takazawa Hideo , Todoroki Yuma , Matsuo Daisuke , Maruyama Mihoko , Imade Mamoru , Yoshimura Masashi , Mori Yusuke

    … We have recently shown that dislocation-free GaN crystals could be grown on a GaN point seed by the Na-flux method. … To enlarge the diameter of dislocation-free GaN crystals, we propose here the coalescence of GaN crystals grown from many isolated point seeds. …

    Applied Physics Express 5(9), 095501-095501-3, 2012-09-25

    JSAP

  • 17

    Large Defect-Free Synthetic Type IIa Diamond Crystals Synthesized via High Pressure and High Temperature

    Sumiya Hitoshi , Tamasaku Kenji

    … Large high-quality type IIa diamond crystals measuring up to 12 mm in diameter were successfully synthesized by the temperature gradient method at high pressure and high temperature, using high-crystalline-quality (001)-oriented seed crystals, and by controlling the temperature conditions with high precision. …

    Jpn J Appl Phys 51(9), 090102-090102-4, 2012-09-25

    JSAP

  • 18

    2c06 Flying-seed-like Liquid Crystals (4) : Synthesis and Mesomorphism of Flying-seed-like Phthalocyanine-Fullerene Dyads  [in Japanese]

    Sasaki Elly , Takagi Yasufumi , Wang Yumin , Ohta Kazuchika

    … Previously, we reported that a series of phthalocyanine (Pc) derivatives substituted by bulky aryl groups without long alkyl chains show columnar mesomorphism, and that they are novel flying-seed-like liquid crystals. … These flying-seed-like liquid crystals may be applicable to solar cell, and they can be expected to show high conversion efficiency. …

    日本液晶学会討論会講演予稿集 (2012), 2c06-1-"2c06-2", 2012-08-20

    CiNii Fulltext PDF - Open Access 

  • 19

    The Effects of Ba-Additive on Growth of a-Plane GaN Single Crystals Using Na Flux Method

    Masumoto Keiko , Someno Tatsuya , Murakami Kosuke , Imabayashi Hiroki , Takazawa Hideo , Todoroki Yuma , Matsuo Daisuke , Kitamoto Akira , Maruyama Mihoko , Imade Mamoru , Yoshimura Masashi , Kitaoka Yasuo , Sasaki Takatomo , Mori Yusuke

    … Here, we grew a-plane GaN crystals using the Na flux method and investigated the effects of a Ba-additive on surface morphology and crystallinity. … We found that the crystallinity of the crystals grown by the Na flux method was greatly improved compared with that of seed substrates. … As a result, a-plane GaN crystals with high crystallinity were produced using the Na flux method with the Ba-additive. …

    Jpn J Appl Phys 51(4), 040203-040203-3, 2012-04-25

    JSAP

  • 20

    Seed-Less Melting Growth of Ge(Si) on Insulator : Large Grain Formation by Si Segregation  [in Japanese]

    KATO Ryusuke , KUROSAWA Masashi , YOKOYAMA Hiroyuki , SADOH Taizoh , MIYAO Masanobu

    絶縁膜上におけるSi添加Ge薄膜[Ge(Si)薄膜]の溶融成長を検討した.SiGe系相図の固相線と液相線で挟まれた領域の温度で急速熱処理を行うと,大粒径(15〜30μm)を有するSiGe結晶粒が成長した.結晶粒には,粒の中心付近でピーク値を有するSi濃度分布が形成されていることが明らかになった.Si濃度のピーク値は,熱処理温度における固相線のSi濃度に一致した.以上の現象は,熱処理時のSi偏析によ …

    Technical report of IEICE. OME 112(19), 61-62, 2012-04-20

    CiNii Fulltext PDF - Subscription