Matsushita Electric Industrial Co., Ltd.

Other

Panasonic Corporation

Konica Minolta, Inc.

Ricoh Company, Ltd.

The Kansai Electric Power Co., Inc.

Yusuke Mori

Hisashi Minemoto

Yasuo Kitaoka

Isao Kidoguchi

Nobuki Itoh

Satoshi Ishizuka

Daisuke Ishiko

Fumio Kawamura

Takatomo Sasaki

Nobuo Sonoda

Katsuya Wakita

Yasuhito Takahashi

Yusuke Ozaki

Yukiko Yoshikawa

Tatsurou Kawamura

Tetsuji Kawakami

Akihiko Ishibashi

Koetsu Saito

Osamu Yamada

Takeshi Hatakeyama

Hidekazu Umeda

Masanori Morishita

Kouichi Hiranaka

Toshimi Nishiyama

Kimihiko Shibuya

Satoshi Wada

Masashi Yoshimura

Junichi Kato

Yoshiaki Hasegawa

Takayuki Negami

Yasutoshi Kawaguchi

Mamoru Imade

Akihiro Miura

Tatsuya Naito

Osamu Kamada

Kazurou Toda

Masashi Ozawa

Hiroaki Hoshikawa

Yasunori Tokunou

Yasunori Kai

Kazuyoshi Tsukamoto

Disclosed is an ultrasound probe including: a piezoelectric body that transmits and receives ultrasound; a backing that is disposed behind the piezoelectric body; and a reflector that is disposed between the piezoelectric body and the backing and that has an acoustic impedance greater than an acoustic impedance of the piezoelectric body; wherein, a thickness of the reflector is within the range of more than 0 to less than 0.05&#x3bb;, where &#x3bb; is a wavelength of the ultrasound.

Ultrasound probe and ultrasound diagnostic apparatus

An ultrasonic probe includes: a piezoelectric element that transmits and receives an ultrasonic wave; one or a plurality of acoustic matching layers disposed on a subject side of the piezoelectric element; and a conductor layer that applies a voltage to the piezoelectric element, wherein the conductor layer is disposed between the piezoelectric element and the acoustic matching layer, or between the plurality of acoustic matching layers, a magnitude of an acoustic impedance of the conductor layer is between a magnitude of an acoustic impedance of a layer disposed on one surface side of the conductor layer and a magnitude of an acoustic impedance of a layer disposed on the other surface side of the conductor layer, and the conductor layer has a Vickers hardness (Hv) of 50 or more and 600 or less.

Ultrasonic probe and ultrasonic diagnostic apparatus

The ultrasound probe includes a piezoelectric element including a piezoelectric composition and an electrode that applies a voltage to the piezoelectric composition. The piezoelectric composition has piezoelectric characteristics expressed by any coordinates included in a region formed by a polyhedron having a plurality of predetermined points as vertexes in Cartesian coordinates (k, &#x3b5;, E) including variables k, &#x3b5;and E.

Piezoelectric element, ultrasound probe and ultrasound imaging apparatus

The present invention is a piezoelectric composition and a piezoelectric element using the piezoelectric composition, the composition being characterized by: having a Perovskite structure represented by general formula ABO3; being represented by composition formula x(Bi0.5K0.5)TiO3-yBi(Mg0.5Ti0.5)O3-zBiFeO3, x+y+z=1 in the composition formula above; and in a triangular coordinate using x, y and z in the composition formula above, having a composition represented by a region which is surrounded by a pentagon ABCDE with apexes of point A (1, 0, 0), point B (0.7, 0.3, 0), point C (0.1, 0.3, 0.6), point D (0.1, 0.1, 0.8) and point E (0.2, 0, 0.8) and which does not include the line segment AE that connects point A (1, 0, 0) and point E (0.2, 0, 0.8).

Piezoelectric composition and method for producing same, piezoelectric element/non-lead piezoelectric element and method for producing same, ultrasonic probe and diagnostic imaging device

A group III element nitride single crystal is grown on a template immersed in a raw material liquid retained in a crucible and containing a group III material and one of an alkali metal and an alkali earth metal. The raw material liquid remaining after the growth of the single crystal is cooled and solidified, and by feeding a hydroxyl group-containing solution into the crucible, the solidified raw material is removed from around the template, and thus the group III element nitride single crystal is taken out from inside the solidified raw material. The template is disposed at a position away from the bottom of the crucible.

Process for producing group III element nitride crystal and apparatus for producing group III element nitride crystal

When a group III nitride crystal is grown in a pressurized atmosphere of a nitrogen-containing gas from a meltincluding at least a group III element, nitrogen and an alkali metal or an alkali earth metal, a melt-holding vesselthat holds the above-described meltis swung about two axes different in direction from each other such as an X-axis and a Y-axis.

Group III nitride crystal, method for growing the group III nitride crystal, and apparatus for growing the same

A method for producing a high-quality group-III element nitride crystal at a high crystal growth rate, and a group-III element nitride crystal are provided. The method includes the steps of placing a group-III element, an alkali metal, and a seed crystal of group-III element nitride in a crystal growth vessel, pressurizing and heating the crystal growth vessel in an atmosphere of nitrogen-containing gas, and causing the group-III element and nitrogen to react with each other in a melt of the group-III element, the alkali metal and the nitrogen so that a group-III element nitride crystal is grown using the seed crystal as a nucleus. A hydrocarbon having a boiling point higher than the melting point of the alkali metal is added before the pressurization and heating of the crystal growth vessel.

Group-III element nitride crystal producing method and group-III element nitride crystal

An object of the present invention is to obtain, with respect to a semiconductor light-emitting element using a group III nitride semiconductor substrate, a semiconductor light-emitting element having an excellent light extraction property by selecting a specific substrate dopant and controlling the concentration thereof. The semiconductor light-emitting element comprises a substrate composed of a group III nitride semiconductor comprising germanium (Ge) as a dopant, an n-type semiconductor layer composed of a group III nitride semiconductor formed on the substrate, an active layer composed of a group III nitride semiconductor formed on the n-type semiconductor layer, and a p-type semiconductor layer composed of a group III nitride semiconductor formed on the active layer in which the substrate has a germanium (Ge) concentration of 2&#xd7;10to 2&#xd7;10cm. The substrate is produced in a nitrogen-containing atmosphere using a melt comprising at least a group III element, an alkali or alkaline earth metal, and germanium (Ge) and nitrogen.

Semiconductor light emitting element, group III nitride semiconductor substrate and method for manufacturing such group III nitride semiconductor substrate

The present invention provides an acoustooptic device usable even with light in the ultraviolet region, free from laser damage and optical damage, and excellent in acoustooptic performance and an optical imaging apparatus using the same. The acoustooptic device according to the present invention includes a high-frequency signal input part (), a transducer part (), and an acoustooptic medium (). A high-frequency signal input from the high-frequency signal input part () is converted into a mechanical vibration by the transducer part (), and an optical characteristic of the acoustooptic medium () varies depending on the mechanical vibration. The acoustooptic medium is formed of a Group III nitride crystal. The optical imaging apparatus according to the present invention includes a light source, an acoustooptic device, a driving circuit, and an image plane. Light from the light source is diffracted by the acoustooptic device in accordance with a signal from the driving circuit and the resultant diffracted light forms an image on the image plane. An acoustooptic medium of the acoustooptic device is formed of a Group III nitride crystal.

Acoustooptic device and optical imaging apparatus using the same

A method for producing Group-III-element nitride crystals by which an improved growth rate is obtained and large high-quality crystals can be grown in a short time, a producing apparatus used therein, and a semiconductor element obtained using the method and the apparatus are provided. The method is a method for producing Group-III-element nitride crystals that includes a crystal growth process of subjecting a material solution containing a Group III element, nitrogen, and at least one of alkali metal and alkaline-earth metal to pressurizing and heating under an atmosphere of a nitrogen-containing gas so that the nitrogen and the Group III element in the material solution react with each other to grow crystals. The method further includes, prior to the crystal growth process, a material preparation process of preparing the material solution in a manner that under an atmosphere of a nitrogen-containing gas, at least one of an ambient temperature and an ambient pressure is set so as to be higher than is set as a condition for the crystal growth process so that the nitrogen is allowed to dissolve in a melt containing the Group III element and the at least one of alkali metal and alkaline-earth metal. The method according to the present invention can be performed by using, for example, the producing apparatus shown in.

Method for producing III group element nitride crystal, production apparatus for use therein, and semiconductor element produced thereby

A method for manufacturing Group III nitride crystals with high quality is provided. By the method, a crystal raw material solution and gas containing nitrogen are introduced into a reactor vessel, which is heated, and crystals are grown in an atmosphere of pressure applied thereto. The gas is introduced from a gas supplying device to the reactor vessel through a gas inlet of the reactor vessel, and then is exhausted to the inside of a pressure-resistant vessel through a gas outlet of the reactor vessel. Since the gas is introduced directly to the reactor vessel, impurities attached to the pressure-resistant vessel and the like into the crystal growing site can be prevented. Further, the gas flows through the reactor vessel, to suppress aggregation of an evaporating alkali metal, etc., at the gas inlet and reduce flow of the metal vapor into the gas supplying device.

Apparatus for production of crystal of group III element nitride and process for producing crystal of group III element nitride

The present invention provides a manufacturing method that makes it possible to manufacture a substrate that is formed of high-quality Group III nitride crystals alone and has less warping. A Group III nitride layer (a seed layer and a selective growth layer) including gaps is formed on a substrate (a sapphire substrate). In an atmosphere containing nitrogen, the surface of the Group III nitride layer is brought into contact with a melt containing alkali metal and at least one Group III element selected from gallium, aluminum, and indium, and thereby the at least one Group III element and the nitrogen are made to react with each other to grow Group III nitride crystals (GaN crystals) on the Group III nitride layer. Thereafter, a part including the substrate and a part including the Group III nitride crystals are separated from each other in the vicinities of the gaps.

Method of manufacturing group III nitride substrate

The present invention provides a method for producing a compound single crystal that can improve a growth rate and grow a large single crystal with high crystal uniformity in a short time, and a production apparatus used for the method. The compound single crystal is grown while stirring a material solution to create a flow from a gas-liquid interface in contact with a source gas toward the inside of the material solution. With this stirring, the source gas can be dissolved easily in the material solution, and supersaturation can be achieved in a short time, thus improving the growth rate of the compound single crystal. Moreover, the flow formed by the stirring goes from the gas-liquid interface where a source gas concentration is high to the inside of the material solution where the source gas concentration is low, so that dissolution of the source gas becomes uniform. Accordingly, it is possible not only to suppress nonuniform nucleation at the gas-liquid interface, but also to improve the quality of the compound single crystal produced.

Method for producing compound single crystal and production apparatus for use therein

A manufacturing apparatus of Group III nitride crystals and a method for manufacturing Group III nitride crystals are provided, by which high quality crystals can be manufactured. For instance, crystals are grown using the apparatus of the present invention as follows. A crystal raw material () and gas containing nitrogen are introduced into a reactor vessel (), to which heat is applied by a heater (), and crystals are grown in an atmosphere of pressure applied thereto. The gas is introduced from a gas supplying device () to the reactor vessel () through a gas inlet of the reactor vessel, and then is exhausted to the inside of a pressure-resistant vessel () through a gas outlet of the reactor vessel. Since the gas is introduced directly to the reactor vessel () without passing through the pressure-resistant vessel (), the mixture of impurities attached to the pressure-resistant vessel () and the like into the site of the crystal growth can be prevented. Further, since the gas flows through the reactor vessel (), there is no aggregation of an evaporating alkali metal, etc., at the gas inlet or the like, and such an alkali metal does not flow into the gas supplying device (). As a result, the quality of Group III nitride crystals obtained can be improved.

The present invention provides a method of manufacturing a gallium nitride single crystal that can suppress the decomposition of gallium nitride and improve production efficiency in a sublimation method. According to the manufacturing method, a material (GaN powder) for the gallium nitride (GaN) single crystal is placed inside a crucible, sublimed or evaporated by heating, and cooled on a substrate surface to return to a solid again, so that the gallium nitride single crystal is grown on the substrate surface. The growth of the single crystal is performed under pressure. The pressure is preferably not less than 5 atm (5&#xd7;1.013&#xd7;10Pa). The single crystal is grown preferably in a mixed gas atmosphere containing NHand N.

Method of manufacturing group III nitride single crystal, device used for the method and group III nitride single crystal obtained by the method

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Osaka, Japan

Hisashi Minemoto