Search Results - "Oka, Tohru"

Identification of type of threading dislocation causing reverse leakage in GaN p–n junctions after continuous forward current stress by Narita, Tetsuo, Kanechika, Masakazu, Kojima, Jun, Watanabe, Hiroki, Kondo, Takeshi, Uesugi, Tsutomu, Yamaguchi, Satoshi, Kimoto, Yasuji, Tomita, Kazuyoshi, Nagasato, Yoshitaka, Ikeda, Satoshi, Kosaki, Masayoshi, Oka, Tohru, Suda, Jun

“…Power devices are operated under harsh conditions, such as high currents and voltages, and so degradation of these devices is an important issue. Our group…”
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Effects of proton irradiation-induced point defects on Shockley–Read–Hall recombination lifetimes in homoepitaxial GaN p–n junctions by Narita, Tetsuo, Kanechika, Masakazu, Tomita, Kazuyoshi, Nagasato, Yoshitaka, Kondo, Takeshi, Uesugi, Tsutomu, Ikeda, Satoshi, Kosaki, Masayoshi, Oka, Tohru, Suda, Jun

“…This work examined the intentional generation of recombination centers in GaN p–n junctions on freestanding GaN substrates. Irradiation with a 4.2 MeV proton…”
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Increase of reverse leakage current at homoepitaxial GaN p-n junctions induced by continuous forward current stress by Narita, Tetsuo, Nagasato, Yoshitaka, Kanechika, Masakazu, Kondo, Takeshi, Uesugi, Tsutomu, Tomita, Kazuyoshi, Ikeda, Satoshi, Yamaguchi, Satoshi, Kimoto, Yasuji, Kosaki, Masayoshi, Oka, Tohru, Kojima, Jun, Suda, Jun

“…Reliability tests involving the application of high electrical stresses were employed to assess GaN-based vertical p-n junctions fabricated on freestanding GaN…”
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Recent development of vertical GaN power devices by Oka, Tohru

“…Gallium nitride (GaN) is an attractive material for high-frequency and high-power devices. Due to the availability of relatively high-quality free-standing…”
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A High-Power Low-Distortion GaAs HBT Power Amplifier for Mobile Terminals Used in Broadband Wireless Applications by Oka, T., Hasegawa, M., Hirata, M., Amano, Y., Ishimaru, Y., Kawamura, H., Sakuno, K.

“…This paper describes technologies of miniaturized high-power low-distortion GaAs HBT power amplifiers with a low-voltage operation for mobile terminals used in…”
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AlGaN/GaN Recessed MIS-Gate HFET With High-Threshold-Voltage Normally-Off Operation for Power Electronics Applications by Oka, T., Nozawa, T.

“…This letter reports normally-off operation of an AlGaN/GaN recessed MIS-gate heterostructure field-effect transistor with a high threshold voltage. The…”
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100 A Vertical GaN Trench MOSFETs with a Current Distribution Layer by Oka, Tohru, Ina, Tsutomu, Ueno, Yukihisa, Nishii, Junya

“…This paper reports on vertical GaN-based trench MOSFETs operating at 100 A for the first time. A current distribution layer (CDL) in a drift layer is employed…”
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Over 10 a operation with switching characteristics of 1.2 kV-class vertical GaN trench MOSFETs on a bulk GaN substrate by Oka, Tohru, Ina, Tsutomu, Ueno, Yukihisa, Nishii, Junya

“…In this paper, we demonstrate 1.2 kV-class vertical GaN trench MOSFETs fabricated on a bulk GaN substrate with high current and switching operations. The…”
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Fully strained heavily carbon-doped GaAs grown by gas-source molecular beam epitaxy using carbontetrabromide and its application to InGaP/GaAs heterojunction bipolar transistors by OUCHI, K, MISHIMA, T, MOCHIZUKI, K, OKA, T, TANOUE, T

“…The lattice-matching conditions in extremely heavily C-doped GaAs (GaAs:C) layers were systematically investigated by using X-ray diffraction measurements from…”
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Characterization of InGaP/GaAs Heterojunction Bipolar Transistors with a Heavily Doped Base by Oka, Tohru, Ouchi, Kiyoshi, Mochizuki, Kazuhiro

“…Characteristics of InGaP/GaAs heterojunction bipolar transistors (HBTs) with a heavily doped base are examined at the base doping level N B ranging from 5×10…”
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Deposition Mechanisms of SiO 2 in Remote Plasma Chemical Vapor Deposition Analyzed by Spatially Resolved Mass Spectroscopy by Fuyuki, Takashi, Tohru Oka, Tohru Oka, Hiroyuki Matsunami, Hiroyuki Matsunami

“…The decomposition of silane ( SiH 4 ) with activated neutral oxygen is investigated by spatially resolved quadrupole mass spectroscopy (QMS). SiH 4 molecules…”
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Single Crystalline Si Metal/Oxide/Semiconductor Field-Effect Transistors Using High-Quality Gate SiO 2 Deposited at 300°C by Remote Plasma Technique by Fuyuki, Takashi, Tohru Oka, Tohru Oka, Hiroyuki Matsunami, Hiroyuki Matsunami

“…High-quality gate SiO 2 for metal/oxide/semiconductor field-effect transistors (MOSFETs) could be deposited at as low as 300° C in remote plasma chemical vapor…”
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Reliability issues of gate oxides and p-n junctions for vertical GaN metal-oxide-semiconductor field-effect transistors (Invited) by Narita, Tetsuo, Kikuta, Daigo, Ito, Kenji, Shoji, Tomoyuki, Mori, Tomohiko, Yamaguchi, Satoshi, Kimoto, Yasuji, Tomita, Kazuyoshi, Kanechika, Masakazu, Kondo, Takeshi, Uesugi, Tsutomu, Kojima, Jun, Suda, Jun, Nagasato, Yoshitaka, Ikeda, Satoshi, Watanabe, Hiroki, Kosaki, Masayoshi, Oka, Tohru

“…We focus on reliability issues of gate oxides and p-n junctions to realize vertical GaN metal-oxide-semiconductor field-effect transistors (MOSFETs). An…”
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Heart-sound analyzing apparatus by Oka, Tohru

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Single crystalline Si metal/oxide/semiconductor field-effect transistors using high-quality gate SiO2 deposited at 300°C by remote plasma technique by FUYUKI, T, OKA, T, MATSUNAMI, H

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A WSi base electrode and a heavily-doped thin base layer for high-speed and low-power InGaP/GaAs HBTs by OKA, T, OUCHI, K, MOCHIZUKI, K, NAKAMURA, T

“…The characteristics of a WSi base electrode and a heavily-doped thin base layer in InGaP/GaAs heterojunction bipolar transistors (HBTs) are demonstrated. An…”
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Recent topics of vertical GaN power devices by Oka, Tohru

“…In this paper, recent topics of vertical GaN power devices fabricated on GaN substrates are presented with particular emphasis on SBDs and trench MOSFETs we…”
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Application of hash to data base machine and its architecture by Kitsuregawa, Masaru, Tanaka, Hidehiko, Moto-Oka, Tohru

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Endochondral ossification of the condyle in rats on a strontium or low-calcium diet by Nagayama, M, Saburi, N, Oka, T, Matsumoto, A

“…The mechanism of abnormal endochondral ossification induced by administration of strontium salts was studied in the mandibular condyles of rats by…”
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Low turn-on voltage GaAs heterojunction bipolar transistors with a pseudomorphic GaAsSb base by Oka, Tohru, Mishima, Tomoyoshi, Kudo, Makoto

“…We have developed GaAs heterojunction bipolar transistors (HBTs) with low turn-on voltage by using pseudomorphic GaAsSb as the base layer. The turn-on voltage…”
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