Koichi Tokudome

Tosoh (Japan)

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Field

DEVELOPMENT OF STABLE DICALCIUM PHOSPHATE AGAINST NaF BY USE OF A SURFACE MODIFICATION TECHNOLOGY (II)

Phosphorus Research Bulletin (2005)

Hiroshi Kobayashi Koichi Tokudome KAZUO YASUZAWA

Very stable dicalcium phosphate(DCP) against NaF was prepared by heat treatment at 200°C with adding Mg compound and condensed phosphate to DCP anhydrous. The crystal form and surface morphology of the improved DCP anhydrous were compared to that of standard DCP anhydrous. These characteristics were the same as those of standard DCP anhydrous. Although our surface modification technology was considered to keep the original characteristics of standard DCP anhydrous, even the crushed sample by an agate mortar showed a sufficient stability against NaF.

Anhydrous

Surface Modification

10.3363/prb1992.19.0_314

Cite

Citations (0)

Low Sheet Resistivity of Transparent Ga-Doped ZnO Film Grown by Atmospheric Spray Pyrolysis

Japanese Journal of Applied Physics (2011)

Yujin Takemoto Minoru Oshima Kenji Yoshino Kouji Toyota Koichiro Inaba

Ga-doped ZnO film on polyethylene terephthalate film was successfully grown at 150 °C by conventional atmospheric spray pyrolysis using diethylzinc-based solution. The samples had an average optical transmittance of more than 80% and were strongly a -axis orientated according to the result of optical transmittance and X-ray diffraction analyses, respectively. The n-type Ga-doped ZnO films had a low sheet resistivity of 250 Ω/□ at an optimal Ga content of 1 at. % upon UV irradiation.

Spray pyrolysis

Diethylzinc

10.1143/jjap.50.088001

Cite

Citations (5)

Growth of Spin-Coated ZnO Films Using Diethylzinc Solution

Japanese Journal of Applied Physics (2011)

Kenji Yoshino Masato Shinmiya Naomi Kamiya Junko Kosaka Minoru Oshima

Nondoped ZnO films on a glass substrate have been successfully grown by conventional spin coating at room temperature using a diethylzinc-based solution. The samples have an optical transmittance of more than 80%, and a smooth surface determined from optical transmittance and scanning electron microscopy, respectively.

Diethylzinc

Spin Coating

10.7567/jjap.50.108001

Cite

Citations (3)

Growth of Spin-Coated ZnO Films Using Diethylzinc Solution

Japanese Journal of Applied Physics (2011)

Kenji Yoshino Masato Shinmiya Naomi Kamiya Junko Kosaka Minoru Oshima

Diethylzinc

Spin Coating

10.1143/jjap.50.108001

Cite

Citations (1)

DEVELOPMENT OF STABLE DICALCIUM PHOSPHATE AGAINST NaF BY USE OF A SURFACE MODIFICATION TECHNOLOGY (I)

Phosphorus Research Bulletin (2005)

Koichi Tokudome Hiroshi Kobayashi KAZUO YASUZAWA

Stable dicalcium phosphate(DCP) against NaF was prepared by heat treatment at 200°C with adding Mg compound and condensed phosphate to DCP anhydrous. The stability of the improved DCP against NaF was higher than that of hydroxyapatite and fluorapatite. It was approximately equal to the SiO2 anhydrous.

Anhydrous

Fluorapatite

Surface Modification

10.3363/prb1992.19.0_307

Cite

Citations (0)

Low-Temperature Growth of ZnO Films by Spray Pyrolysis

Japanese Journal of Applied Physics (2011)

Kenji Yoshino Yujin Takemoto Minoru Oshima Kouji Toyota Koichiro Inaba

Nondoped ZnO film on a polyethylene terephthalate film was successfully grown by conventional spray pyrolysis at 100 °C using a diethylzinc-based solution under air atmosphere. The samples had an average optical transmittance of more than 80%, a flat surface, and an a-axis orientation from the optical transmittance, scanning electron microscopy, and X-ray diffraction measurements, respectively. It was assumed that the growth at low temperature was attributed to atmospheric oxygen and/or steam.

Spray pyrolysis

Diethylzinc

10.7567/jjap.50.040207

Cite

Citations (7)

Short-Period Superlattices of (GaP)_n(AlP)_n Grown by Metalorganic Vapor Phase Epitaxy

Japanese Journal of Applied Physics (1991)

Akio Morii Isao Ohno Atsushi Kanda Kazumasa Arai Koichi Tokudome

Short-period superlattices of (GaP) n (AlP) n have been grown by metalorganic vapor phase epitaxy. X-ray diffraction measurements have confirmed the formation of the structures, where n ranges from 4 to 10. Low-temperature photoluminescence has shown characteristic emission peaks, which shift toward higher energies and tend to increase in intensity with decreasing n . These results, together with the band discontinuity between GaP and AlP which was estimated from that between GaP and Al 0.6 Ga 0.4 P, strongly indicate that the (GaP) n (AlP) n system forms the superlattices of a type-II band alignment.

Vapor phase

Discontinuity (linguistics)

10.1143/jjap.30.l1244

Cite

Citations (41)

Low-Temperature Growth of ZnO Films by Spray Pyrolysis

Japanese Journal of Applied Physics (2011)

Kenji Yoshino Yujin Takemoto Minoru Oshima Kouji Toyota Koichiro Inaba

Nondoped ZnO film on a polyethylene terephthalate film was successfully grown by conventional spray pyrolysis at 100 °C using a diethylzinc-based solution under air atmosphere. The samples had an average optical transmittance of more than 80%, a flat surface, and an a -axis orientation from the optical transmittance, scanning electron microscopy, and X-ray diffraction measurements, respectively. It was assumed that the growth at low temperature was attributed to atmospheric oxygen and/or steam.

Spray pyrolysis

Diethylzinc

10.1143/jjap.50.040207

Cite

Citations (16)

Optical and electrical characterization of transparent Ga‐doped ZnO thin films grown by atmospheric spray pyrolysis using diethylzinc solution

Physica status solidi. C, Conferences and critical reviews/Physica status solidi. C, Current topics in solid state physics (2013)

Minoru Oshima Akiko Ide Akiko Mochihara Kenji Yoshino Yujin Tanikemoto

Abstract Non‐doped and Ga‐doped ZnO film on glass substrate were successfully grown at 150 °C by conventional atmospheric spray pyrolysis using diethylzinc‐based solution. The samples had an average optical transmittance of more than 80% and were strongly a ‐axis orientated according to the results of optical transmittance and X‐ray diffraction analysis, respectively. The n‐type Ga‐doped ZnO films had a low resistivity of 2.3 × 10 –3 Ωcm, a carrier concentration of 1.1 × 10 20 cm –3 and a mobility of 10 cm 2 (Vs) –1 at an optimal Ga content of 2 at% upon UV irradiation. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Diethylzinc

Spray pyrolysis

10.1002/pssc.201200854

Cite

Citations (6)

Development of the testing method for mixing explosion hazards of pyrophoric substances

Yoshihiko Sato Ken Okada Koichi Tokudome Takehiro Matsunaga

Source

Cite

Citations (1)