Hitachi Cable, Inc.

Sumitomo Chemical Company, Limited

Hitachi Metals, Ltd.

Sciocs Company Limited

Taichiroo Konno

Masahiro Arai

Hajime Fujikura

Kazuyuki Iizuka

Michiko Matsuda

Yuichi Oshima

Takashi Furuya

Katsuya Akimoto

Nobuaki Kitano

Takehiko Tani

Ken Takahashi

A nitride semiconductor template includes a substrate, and a chlorine-containing nitride semiconductor layer. The chlorine-containing nitride semiconductor layer contains an iron concentration of not higher than 1&#xd7;10cm.

Metal chloride gas generator, hydride vapor phase epitaxy growth apparatus, and nitride semiconductor template

A nitride semiconductor crystal producing method, includes growing a nitride semiconductor crystal over a seed crystal substrate, while applying an etching action to an outer end of the seed crystal substrate during the growing of the nitride semiconductor crystal.

Nitride semiconductor crystal producing method including growing nitride semiconductor crystal over seed crystal substrate

There is provided a nitride semiconductor epitaxial substrate having a group III nitride semiconductor layer with C-plane as a surface, grown on a substrate via a buffer layer of the group III nitride semiconductor containing Al, wherein the buffer layer has an inversion domain on the surface.

Nitride semiconductor epitaxial substrate and nitride semiconductor device

A metal chloride gas generator includes a reactor including a receiving section for receiving a metal on an upstream side and a growing section in which a growth substrate is placed on a downstream side, a raw material section heater and a growing section heater each of which heats an inside of the reactor, an upstream end comprising a gas inlet, and a gas inlet pipe arranged to extend from the upstream end via the receiving section to the growing section, for introducing a chloride gas from the upstream end to supply the chloride gas to the receiving section and supplying a metal chloride gas produced by a reaction between the chloride gas and the metal in the receiving section to the growing section. The gas inlet pipe includes a suppressing section for suppressing an optical waveguiding phenomenon which waveguides a radiant heat from the growing section heater or the growing section.

Metal chloride gas generator, hydride vapor phase epitaxy growth apparatus, and method for fabricating a nitride semiconductor template

A metal chloride gas generator includes: a tube reactor including a receiving section for receiving a metal on an upstream side, and a growing section in which a growth substrate is placed on a downstream side; a gas inlet pipe arranged to extend from an upstream end with a gas inlet via the receiving section to the growing section, for introducing a gas from the upstream end to supply the gas to the receiving section, and supplying a metal chloride gas produced by a reaction between the gas and the metal in the receiving section to the growing section; and a heat shield plate placed in the reactor to thermally shield the upstream end from the growing section. The gas inlet pipe is bent between the upstream end and the heat shield plate.

Method of manufacturing a nitride semiconductor epitaxial substrate

A nitride semiconductor template includes a substrate, and a group III nitride semiconductor layer formed on the substrate and including a Si-doped layer doped with Si as an uppermost layer thereof. The group III nitride semiconductor layer has a total thickness of not less than 4 &#x3bc;m and not more than 10 &#x3bc;m. The Si-doped layer includes a Si concentration gradient layer having a carrier concentration that gradually decreases toward an outermost surface thereof so as to be not less than 1&#xd7;10cmand not more than 5&#xd7;10cmat the outermost surface of the group III nitride semiconductor layer.

Nitride semiconductor template and light-emitting diode

A light-emitting element includes a semiconductor substrate, a light emitting portion including an active layer, a reflective portion between the semiconductor substrate and the light emitting portion, and a current dispersion layer on the light emitting portion. The reflective portion includes a plurality of pair layers each including a first semiconductor layer and a second semiconductor layer. The first semiconductor layer has a thickness Tdefined by a formula (1) and the second semiconductor layer has a thickness Tdefined by a formula (2), where &#x3bb;represents a peak wavelength of the light emitted from the active layer, nrepresents a refractive index of the first semiconductor layer, nrepresents a refractive index of the second semiconductor layer, nrepresents a refractive index of a first cladding layer, and &#x3b8; represents an incident angle of light from the first cladding layer to the second semiconductor layer. 

Light-emitting element

A nitride semiconductor crystal producing method, a nitride semiconductor epitaxial wafer, and a nitride semiconductor freestanding substrate, by which it is possible to suppress the occurrence of cracking in the nitride semiconductor crystal and to ensure the enhancement of the yield of the nitride semiconductor crystal. The nitride semiconductor crystal producing method includes growing a nitride semiconductor crystal over a seed crystal substrate, while applying an etching action to an outer end of the seed crystal substrate during the growing of the nitride semiconductor crystal.

Nitride semiconductor crystal producing method, nitride semiconductor epitaxial wafer, and nitride semiconductor freestanding substrate

A nitride semiconductor template includes a substrate, and a group III nitride semiconductor layer having an oxygen-doped layer formed on the substrate, and a silicon-doped layer formed on the oxygen-doped layer. A total thickness of the group III nitride semiconductor layer is not smaller than 4 &#x3bc;m and not greater than 10 &#x3bc;m, and an average silicon carrier concentration in the silicon-doped layer is not lower than 1&#xd7;10cmand not higher than 5&#xd7;10cm.

Nitride semiconductor template and light-emitting diode including oxygen-doped layer and silicon-doped layer formed on the oxygen-doped layer

A light emitting element includes a semiconductor substrate, a light emitting part having a first and second conductivity type cladding layers and an active layer sandwiched between the cladding layers. A reflecting part is disposed between the substrate and the light emitting part. A current dispersing layer disposed on a side of the light emitting part opposite to the reflecting. The reflecting part has at least three pair layers of first and second semiconductor layers, the first semiconductor layer has a first thickness, the second semiconductor layer has a second thickness and a plurality of pair layers of the reflecting part have a different thickness to each other as values of the incident angle of light are different with respect to each pair layer. At least one pair layer is defined by the incident angle of light being not less than 50 degrees.

Light emitting element

A light-emitting element includes a semiconductor substrate, a light emitting portion including an active layer sandwiched between a first cladding layer of a first conductivity type and a second cladding layer of a second conductivity type different from the first conductivity type, a reflective portion provided between the semiconductor substrate and the light emitting portion for reflecting light emitted from the active layer, and a current spreading layer provided on the light emitting portion opposite to the reflective portion and including a concavo-convex portion on a surface thereof. The reflective portion includes a plurality of pair layers each including a first semiconductor layer and a second semiconductor layer different from the first semiconductor layer, and the first semiconductor layer has a thickness Tdefined by formulas (1) and (3), and the second semiconductor layer has a thickness Tdefined by formulas (2) and (4).

Light-emitting element and method of making the same

An epitaxial wafer, a light-emitting element, a method of fabricating the epitaxial wafer and a method of fabricating the light-emitting element, which have a high output and a low forward voltage, and can be fabricated without increasing fabricating cost, are provided. The epitaxial wafer is formed with a light-emitting portion, a reflective portion provided between a semiconductor substrate and the light-emitting portion and a current dispersing layer having first and second current dispersing layers, wherein the reflective portion has plural pairs of layers having first and second semiconductor layers wherein the first semiconductor layer has a thickness of Tdefined by Equation (1), the second semiconductor layer has a thickness of Tdefined by Equation (2), and the second current dispersing layer has a high carrier density or a high impurity density and is provided with the convexoconcave portion on the surface.

Epitaxial wafer, light-emitting element, method of fabricating epitaxial wafer and method of fabricating light-emitting element

A light-emitting element includes a semiconductor substrate, a light emitting layer portion including an active layer on the semiconductor substrate, a first reflective layer between the semiconductor substrate and the active layer for reflecting light emitted from the active layer; and a second reflective layer between the semiconductor substrate and the first reflective layer for reflecting light with a wavelength different from that of the light reflected by the first reflective layer. The second reflective layer reflects light with a wavelength longer than that of the light reflected by the first reflective layer.

A first conductivity type cladding layer, a first side multilayer, an active layer, a second side multilayer, and a second conductivity type cladding layerare provided in a semiconductor light emitting device. The first side multilayeris provided between the first conductivity type cladding layerand the active layer, and the second side multilayeris provided between the active layerand the second conductivity type cladding layer. Each of the multilayeris transparent with respect to the light generated at the active layer, having a bandgap larger than that of the active layer, and lattice-matched with the active layer

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Hitachi, Japan

Taichiroo Konno