Kabushiki Kaisha Toshiba

Nippon Steel Corporation

Nippon Steel Materials Co., Ltd.

Tokyo Shibaura Denki Kabushiki Kaisha

Masaki Okajima

Genichi Hatakoshi

Koichi Nitta

Yukie Nishikawa

Nawoto Motegi

Shinji Tokumaru

Minoru Watanabe

Masayuki Ishikawa

Kazuhiko Itaya

Yukio Watanabe

Naohiro Shimada

Kensuke Okazawa

Yutaka Uematsu

Hideto Sugawara

Yoshio Iizuka

Atsushi Sugahara

Hiroki Iwanaga

Aira Hotta

Kazutaka Terashima

John Rennie

Kazuyuki Sunohara

Koichi Chiba

Masaru Nakamura

Seizaburo Shimizu

Tetsuo Sadamasa

Motoyuki Yamamoto

Jiro Kondo

Hitoshi Dohnomae

Akihiro Ono

Hideaki Kinoshita

Nobuaki Ito

Takamasa Ohno

Hiroshi Yamane

Tadashi Komatsubara

Hiroko Nagasaka

Jirou Kondou

Yuhei Muto

Yuhei Muro

Minoru Hayata

Gen-ichi Hatakoshi

Nobuyuki Matsuura

Hatsumi Kawata

The present invention provides a high purity silicon production system and production method suitable for using inexpensive metallurgical grade metal silicon as a material and using the slag refining method to produce high purity silicon with a purity of 6N or more suitable for solar battery applications, in particular, high purity silicon with a boron content of at least not more than 0.3 mass ppm, inexpensively on an industrial scale, that is, a high purity silicon production system and production method using the slag refining method wherein a direct electromagnetic induction heating means having the function of directly heating the molten silicon in the crucible by electromagnetic induction is arranged outside the outside wall surface of the above crucible and the crucible is formed by an oxidation resistant material at least at a region where the molten silicon contacts the crucible inside wall surface at the time of not powering the direct electromagnetic induction heating means.

High purity silicon production system and production method

The present invention provides a method of refining low purity Si by a slag, in particular removing B, which suppresses wear of the reaction vessel due to the slag and produces high purity Si used for solar battery materials etc. at a low cost, comprising adding SiOand an alkali oxide or alkali carbonate as a slag material into molten Si to form a slag during which adding one or more types of materials among materials the same as the reaction vessel material used or ingredients included in the reaction vessel material into the slag so as to remove the impurities in the molten Si.

Method of refining Si

A process for production of Si, characterized by adding an oxide, hydroxide, carbonate or fluoride of an alkali metal element, or an oxide, hydroxide, carbonate or fluoride of an alkaline earth metal element, or two or more of such compounds, to solid SiO in a total molar amount of from 1/20 to 1000 times with respect to the moles of solid SiO, heating the mixture at between the melting point of Si and 2000&#xb0; C. to induce a chemical reaction which produces Si and separating and recovering the Si from the reaction by-product, for the purpose of inexpensively and efficiently producing Si from various forms of solid SiO with no industrial value produced from Si production steps and the like.

Method for production of silicon

A novel display device suitable as a portable display device is disclosed. The device includes a pair of substrates and a light modulation layer sandwiched between the substrates. A functional gel is adapted to be deformed by an electric field applied between a pair of electrodes interposed between the substrates, thereby regulating the light incident on the light modulation layer. A high contrast, a high reflectance and a high light utilization are achieved without regard to the angle of visibility.

Display device

A semiconductor laser device includes a substrate, a first cladding layer formed on the substrate, an active layer formed on the first cladding layer, and a second cladding layer formed on the active layer having a conductivity type different from that of the first cladding layer, wherein at least one of the first and second cladding layers has a multiquantum barrier structure. The width of the first quantum barrier of the multiquantum barrier structure relative to the side of the active layer is 24 to 100 nm, the width of the second quantum barrier of the multiquantum barrier structure relative to the side of the active layer is 5 to 20 nm, and the multiquantum barrier structure is constituted by alternately stacking first thin layers consisting of In.sub.z (Ga.sub.1-x Al.sub.x).sub.1-z P (x is 0.7 to 1.0 and z is 0 to 1.0) and second thin layers consisting of In.sub.z (Ga.sub.1-y Al.sub.y).sub.1-z P (y is 0 to 0.3 and z is 0 to 1.0).

Semiconductor laser device

A wavelength converting optical device includes an optical waveguide which has a waveguide portion and a cladding portion, at least one of which is formed of a nonlinear optical material. A fundamental wave, incident on the waveguide portion from an input end face of the waveguide, is converted into an optical second harmonic wave by Cerenkov radiation and is radiated into the cladding portion. The radiated second harmonic wave is output from an output end face of the waveguide. A reflecting film is provided on the emerging end face of the waveguide. The reflecting film includes a high reflectivity with respect to the fundamental wave of a guide mode and a low reflectivity with respect to the optical second harmonic wave. A wave front converting element is arranged to oppose the reflecting film. The converting element has a diffraction grating for converting the second harmonic wave, emerging from the output end face of the waveguide, into a plane wave.

Wavelength converting optical device

According to this invention, in a semiconductor laser, an n-type InGaAlP cladding layer, an InGaP active layer, and a p-type InGaAlP cladding layer are sequentially grown on an n-type GaAs substrate to form a double hetero structure. The active layer is constituted by an ordered structure having regularity in the &lt;111&gt; directions, and the p-type cladding layer is constituted by a disordered structure. Band discontinuity in conduction band between the active layer and the p-type cladding layer is increased to improve the temperature characteristics of the laser.

Semiconductor laser whose active layer has an ordered structure

A semiconductor laser device for radiating a laser beam from a double heterostructure section in which injected carriers having an energy source of the laser beam are confined consists of a compound semiconductor substrate with a prescribed lattice constant for loading the double heterostructure section, a lattice mismatched active layer with a first lattice constant which is 0.5% to 2.0% larger than the lattice constant of the substrate in the double heterostructure section for radiating the laser beam, a lattice mismatched cladding layer with a second lattice constant which is 0.2% to 2.0% smaller than the lattice constant of the substrate for confining the injected carriers in the active layer, and a cladding layer for confining the injected carriers in the active layer by co-operating with the lattice mismatched cladding layer.

A semiconductor laser device comprises a compound semiconductor substrate, a first cladding layer formed on the substrate, an active layer formed on the first cladding layer, made of In.sub.1-y (Ga.sub.1-x Al.sub.x).sub.y P material (0.ltoreq.x&lt;1, 0.ltoreq.y&lt;1), and a second cladding layer formed on the active layer. These first cladding layer, the active layer, and the second cladding layer forms a double heterostructure. A lattice constant of the active layer is larger than that of the substrate by 0.3% or more. The lattice constants of the first and second cladding layers are substantially equal to that of the substrate.

Semiconductor device having an active layer made of InGaAlP material

A visible-light wavelength continuous oscillation laser is disclosed which has an N type GaAs substrate, an N type GaAlAs cladding layer formed on the substrate, and a non-doped GaAlAs active layer formed on the cladding layer. The laser further includes two N type GaAlAs layers, a P type GaAlAs optical guide layer, a P type cladding layer consisting of upper and lower portions, and a ridge section. The N type GaAlAs layers contact both sides of the ridge section. The optical guide layer is sandwiched between the upper and lower portions of the P type cladding layer, is located within the ridge section, and has a refractive index greater than that of the P type cladding layer. The distance between the active layer and the optical guide layer does not depend on the condition in which etching is performed to form the ridge section, but depends basically on the time required to grow crystal.

Transverse-mode oscillation semiconductor laser device

A visible light emitting semiconductor laser has a double-heterostructure section above the N-type GaAs substrate, which is composed of a nondoped InGaP active layer sandwiched between an N type InGaAlP cladding layer and a P type InGaAlP cladding layer. A P type InGaP thin-film layer formed on the P type cladding layer functions as an etching stopper. Formed sequentially on the etching stopper layer are a P type cladding layer and an N type GaAs current-blocking layer, which have a stripe-shaped groove section in and around their central portion. The groove section has an opening at the top and the bottom portion narrower than the opening, presenting an inverse-trapezoidal cross-sectional profile. This arrangement makes the width of the optical confinement region of the semiconductor laser narrower than that of the current injection region.

Visible light emitting semiconductor laser with inverse mesa-shaped

A semiconductor laser diode includes two semiconductive cladding layers of different conductivity types, which are stacked on a substrate. An active layer of an undoped semiconductor film is sandwiched between the cladding layers. A channel groove is formed in a current blocking layer and the underlying cladding layer, to be deep enough to cause the current blocking layer to be divided into two parts. A waveguide layer covers the channel groove and the current-blocking layer, to provide a slab-coupled waveguide structure for transverse mode oscillation. The second cladding layer, the current-blocking layer, and the waveguide layer are composed of gallium arsenide containing aluminum.

Transverse-mode stabilized semiconductor laser diode with slab-coupled

Oxygen or a mixed gas containing oxygen, or a chemical flame produced by a mixture of a combustion gas and a combustion-assisting gas containing oxygen, is blown against the surface of molten iron to cause radiation emission. The radiations are divided into components of different wavelengths, and the resulting emission spectra are measured to determine the composition of the molten iron.

Method of spectroscopically determining the composition of molten iron

A light emitting diode is disclosed which includes an N-GaAs substrate, a double hetero-junction structure obtained by forming an N-GaAlAs clad layer, a P-GaAs active layer and a P-GaAlAs clad layer on the substrate in that order, and a current narrowing structure obtained by selectively forming a contact metal on the P-GaAlAs clad layer in the double hetero-junction structure with the contact metal formed around the contact metal. In the light emitting diode so manufactured, the double hetero-junction structure is formed by a metal organic vapor deposition method. The N-GaAlAs clad layer is of a three-layer structure with one layer of a narrower forbidden band width sandwiched between the remaining two layers of a wider forbidden band width.

Light emitting diode formed of a compound semiconductor material

A hetero junction type semiconductor laser device is provided wherein a hetero layer is formed on a clad layer leaving a stripe shape portion. The clad layer is formed on an active layer over a substrate. At least two coating layers of the same conductivity type as the clad layer are formed on the hetero layer so as to have a current confining effect and a built-in waveguide effect. The refractive index of the coating layers which is nearer to the active layer is greater than the refractive index of the clad layer and the refractive index of the other coating layer is smaller than the refractive index of the coating layer which is nearer to the active layer. Using this construction, a low lasing threshold current is achieved.

Semiconductor laser device having current confining and built-in

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Kawasaki, Japan

Masaki Okajima