Rohm Co., Ltd.

Sony Corporation

Mitsubishi Electric Corporation

Other

Ishikawajima-harima Heavy Industries Co., Ltd.

Norikazu Ito

Hiroyuki Fujita

Satoshi Yoneya

Masakazu Yoshimoto

Satoshi Katsuo

Tomohisa Shiga

Jun Yoshikawa

Satoshi Yutani

Koichi Sato

Masaki Hirose

Minoru Akutsu

Ken Nakahara

Taketoshi Tanaka

Shinya Takado

Kenji Yamamoto

Tetsuya Fujiwara

Atsushi Yamaguchi

Takuya Shimomugi

Yuichi Kojima

Masayuki Sonobe

Katsuhiko Saito

Masahiro Fukuda

Yosuke Shinomoto

Shigeo Umehara

Katsuyuki Amano

Masahiro Kato

Kazunori Hatakeyama

Tsutomu Yamamoto

Kenta Yuasa

Shota Kamiya

Kazuaki Tsutsumi

Atsushi Hasebe

Shouji Nakamura

Shintaro Mizutani

Shoji Isoda

Masaki Yamada

Akira Yamaguchi

Akihiko Iwata

Koichi Arisawa

Keisuke Uemura

Atsushi Kikuchi

Hirotaka Otake

Noriyuki Shimoji

Takashi Yamakawa

Takahiro Urakabe

Hiroyuki Ota

Tsuyoshi Tsutsui

Mitsuo Kashima

Mitsuhiko Sakai

Makoto Tanikawa

Masunori Shibata

Ichiro Fujisawa

Tomoko Takagi

Takuo Kugiya

Tetsuhiro Tanabe

Yusuke Tani

Masashi Ueda

Tomohiro Date

Michio Kondo

Yoshimi Watabe

Masayuki Kakio

Taro Shigata

Tomomi Higashikawa

Akihisa Matsuda

Shoji Nakamura

Atsuo Matsuyama

Tetsuo Fujii

Yoshinori Koishikawa

Gentaro Okayasu

Kazushige Sawada

Masato Handa

Hitoshi Tanifuji

Syuichi Takazawa

Ryohei Kato

Shinichi Tamai

Yuichi Kojima, Deceased

Kazutaka Iinuma

Yoji Shimizu

Ryouhei Kato

Horoyuki Fijita

Kunimitsu Kishimoto

Norihiko Sugisaki

A nitride semiconductor device includes an electron transit layer, an electron supply layer that is formed on the electron transit layer, a gate layer that is formed on the electron supply layer and contains an AlGaN (0<X<1) based material containing a first impurity, a gate electrode that is formed on the gate layer and is in Schottky junction with the gate layer, and a source electrode and a drain electrode that are electrically connected to the electron supply layer. By this arrangement, a gate withstand voltage can be improved and therefore, a nitride semiconductor device of high reliability can be provided.

Nitride semiconductor device

A nitride semiconductor device includes an electron transit layer that is formed of a nitride semiconductor, an electron supply layer that is formed on the electron transit layer, and formed of a nitride semiconductor and that has a recess which reaches the electron transit layer from a surface, a thermal oxide film that is formed on the surface of the electron transit layer exposed within the recess, a gate insulating film that is embedded within the recess so as to be in contact with the thermal oxide film, a gate electrode that is formed on the gate insulating film and that is opposite to the electron transit layer across the thermal oxide film and the gate insulating film, and a source electrode and a drain electrode that are provided on the electron supply layer at an interval such that the gate electrode intervenes therebetween.

Nitride semiconductor device and fabrication method therefor

A piezoelectric element includes a single crystal piezoelectric film, wherein the single crystal piezoelectric film includes an aluminum nitride film and wherein a full width at half maximum at (002) diffraction peak of the aluminum nitride film is smaller than 1.00 degree.

Piezoelectric element, method of manufacturing the same, surface acoustic wave element, and piezoelectric thin film resonance element

A nitride semiconductor deviceincludes a first nitride semiconductor layerthat constitutes an electron transit layer, a second nitride semiconductor layerthat is formed on the first nitride semiconductor layer, is larger in bandgap than the first nitride semiconductor layer, and constitutes an electron supply layer, and a gate portionthat is formed on the second nitride semiconductor layer. The gate portionincludes a first semiconductor gate layerof a ridge shape that is disposed on the second nitride semiconductor layerand is constituted of a nitride semiconductor containing an acceptor type impurity, a second semiconductor gate layerthat is formed on the first semiconductor gate layerand is constituted of a nitride semiconductor with a larger bandgap than the first semiconductor gate layer, and a gate electrodethat is formed on the second semiconductor gate layerand is in Schottky junction with the second semiconductor gate layer

A nitride semiconductor device includes an electron transit layer () that is formed of a nitride semiconductor, an electron supply layer () that is formed on the electron transit layer (), that is formed of a nitride semiconductor whose composition is different from the electron transit layer () and that has a recess () which reaches the electron transit layer () from a surface, a thermal oxide film () that is formed on the surface of the electron transit layer () exposed within the recess (), a gate insulating film () that is embedded within the recess () so as to be in contact with the thermal oxide film (), a gate electrode () that is formed on the gate insulating film () and that is opposite to the electron transit layer () across the thermal oxide film () and the gate insulating film (), and a source electrode () and a drain electrode () that are provided on the electron supply layer () at an interval such that the gate electrode () intervenes therebetween.

A nitride semiconductor device includes a first impurity layer made of an AlGaN (0&#x3c;X&#x2264;1) based material and containing a first impurity with which a depth of an acceptor level from a valence band (E-E) is made not less than 0.3 eV but less than 0.6 eV, an electron transit layer formed on the first impurity layer, an electron supply layer formed on the electron transit layer, agate electrode formed on the electron transit layer, and a source electrode and a drain electrode formed such that the source electrode and the drain electrode sandwich the gate electrode and electrically connected to the electron supply layer.

An elevator device including on-car presence detection units, each being configured to detect presence of a person on top of a corresponding one of cars, on-car operation panels, each to be operated for a manual operation of the corresponding one of cars, and an elevator control device including a car operation approval unit configured to approve or cancel the operation on the on-car operation panels. When the on-car presence detection units have detected the presence of persons on top of the plurality of cars, the operation on the on-car operation panels of all the cars is canceled by the car operation approval unit. When the on-car presence detection unit has detected the presence of a person on top of one of the plurality of cars, the car operation approval unit approves the operation on the on-car operation panel of any one of the plurality of cars.

Elevator device

A motor drive apparatus includes: inverter modules equivalent in number to phases of a motor; and a control unit that generates a PWM signal for driving the inverter modules by using PWM. Each of the inverter modules includes: a plurality of pairs of switching elements, each pair of switching elements including two switching elements connected in series; a drive circuit; and a protection circuit. The plurality of pairs of switching elements is connected in parallel, and power GNDs that are reference terminals of the plurality of pairs of switching elements, a control GND that is a reference terminal of the drive circuit, and a terminal for overcurrent fault input in the protection circuit are independently exposed to the outside. The power GNDs and the control GND are connected to a single point on a printed circuit board by a wiring pattern.

Motor drive apparatus, refrigeration cycle apparatus and air conditioner

A motor driving device that converts alternating-current power to direct-current power and drives a motor, the motor driving device including a printed circuit board having a first plate surface and a second plate surface, having an inverter module and an inverter module provided on the first plate surface, having a first power pattern provided on the second plate surface and connected to the inverter module, having a second power pattern provided on the second plate surface and connected to the inverter module, and having a jumper portion to connect the first power pattern and the second power pattern. A cross-sectional area of the jumper portion is larger than a cross-sectional area of the first power pattern or the second power pattern.

Motor driving device and air conditioner

A nitride semiconductor device includes: an electron transit layer including GaxIn1-xN (0&#x3c;x&#x2264;1); an electron supply layer formed on the electron transit layer and including AlyIn1-yN (0&#x3c;y&#x2264;1); a gate insulating film formed to pass through the electron supply layer to contact the electron transit layer; and a gate electrode facing the electron transit layer with the gate insulating film interposed therebetween, wherein, in the electron transit layer, a portion contacting the gate insulating film and a portion contacting the electron transit layer are flush with each other.

Nitride semiconductor device and method for manufacturing the same

A motor drive apparatus driving a motor as a three-phase motor converting direct power into three-phase alternating power, includes: inverter modules equivalent in number to phases of the motor; and a control unit generating PWM signals used to drive the inverter modules with PWM. The inverter modules each include a plurality of switching element pairs connected in parallel, each of the switching element pairs including two switching elements connected in series.

Motor drive apparatus and air conditioner

A motor drive apparatus which drives a motor includes inverter modules equal in number to phases of the motor. Each of the inverter modules includes a plurality of switching element pairs. Each of the switching element pairs is defined by two switching elements connected in series. In each of the inverter modules, the plurality of switching element pairs are connected in parallel, and each of resistance values of gate resistors connected to the switching elements is set for the corresponding switching element connected thereto.

There are provided the same number of inverter modules as the number of phases of a motor, and an inverter control unit that generates PWM signals used to drive the inverter modules in PWM. Three phase outputs from each of the inverter modules are coupled to form a phase output signal for one phase of the motor while capacitors are mounted between control GNDs of the inverter modules and power GNDs of the inverter modules. Consequently, even if a surge voltage is generated in a GND wiring at the time of a switching operation of switching elements in the inverter modules, the application of the surge voltage to the switching elements can be suppressed.

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Kyoto, Japan

Norikazu Ito