Shin-etsu Handotai Co., Ltd.

Nanoteco Corporation

Ntt Docomo, Inc.

Shin-etsu Handotai Kabushiki Kaisha

Other

Masato Yamada

Takao Takenaka

Masanobu Takahashi

Nobuhiko Noto

Shinji Nozaki

Hiroshi Morisaki

Kazuo Uchida

Susumu Higuchi

Masayuki Shinohara

Masahisa Endo

Makoto Kawasaki

Yusuke Fukazawa

Munehisa Yanagisawa

Hitoshi Ikeda

Shinji Orimo

Kazunori Hagimoto

Ken Aihara

Jun-ya Ishizaki

Junya Ishizaki

Toshio Otaki

Shunichi Ikeda

Jun Ikeda

Kingo Suzuki

Kousei Yumoto

Takuo Takenaka

Yukihiro Yamaguchi

Tadashi Sakurai

Yutaka Tamura

Keizou Adomi

Kenji Sakai

A semiconductor phosphor configured to exhibit photoluminescence upon irradiation with excitation light, including: at least one active layer made of a compound semiconductor and containing an n-type or p-type dopant; and at least two barrier layers made of a compound semiconductor and having a larger band gap than the active layer. The active layer and the barrier layers are alternately stacked. This provides a semiconductor phosphor which allows easy wavelength adjustment, high efficiency and stability.

Semiconductor phosphor

A visiting destination prediction device includes: a user position information acquiring unit configured to acquire user position information indicating a position of a user; an action history acquiring unit configured to acquire information on an action history of the user; and a visiting POI estimating unit configured to estimate a visiting POI which is a visiting destination of the user on the basis of a relationship between an acquired user position and a previously stored POI position and a relationship between the acquired action history of the user in a predetermined period and previously stored POI relevant information.

Visiting destination prediction device and visiting destination prediction method

A visiting destination prediction device includes: a user position information acquiring unit configured to acquire user position information indicating a position of a user; a stationary position deriving unit configured to derive a stationary position of the user on the basis of the acquired user position information; and a visiting POI estimating unit configured to estimate a visiting POI which is a visiting destination of the user on the basis of a relationship between the derived stationary position of the user and a predetermined POI position of a POI which is able to be the visiting destination of the user. The stationary position deriving unit derives the stationary position which is expressed by an area on the basis of an error and a degree of dispersion of a series of pieces of the acquired user position information.

A composite growth-assisting substrateis formed by epitaxially growing a separation-assisting compound semiconductor layercomposed of a non-GaAs III-V compound semiconductor single crystal, and then a sub-substratecomposed of a GaAs single crystal in this order, on a first main surface of a substrate bulkcomposed of a GaAs single crystal. The sub-substrate portionis then separated from the composite growth-assisting substrate, so as to be left as a residual substrate portionon a second main surface of the main compound semiconductor layer, and a portion of the residual substrate portionis cut off to thereby form a cut-off portionhaving a bottom surface used as a light extraction surface. By this configuration, the light emitting device is provided as allowing effective use of the GaAs substrate, and increasing the light extraction efficiency.

Light emitting device and method of fabricating the same

A light emitting element () comprising an element chip (C) provided, at least in a partial section in the thickness direction thereof, with a part of reduced cross-section where the cross sectional area decreases continuously or stepwise in the direction perpendicular to the thickness direction from the first major surface side toward the second major surface side. A part of a molded section () has a first mold layer () covering at least the part of reduced cross-section, and a second mold layer () covering the outside of the first mold layer (), wherein the first mold layer () is composed of a polymer mold material softer than that of the second mold layer (). A light emitting element, having such a structure that the element chip bonded onto a metal stage is not stripped easily even if mold resin expands, is thereby provided.

Light emitting device

A light-emitting devicehas ITO transparent electrode layersused for applying drive voltage for light-emission to a light-emitting layer section, and is designed so as to extract light from the light-emitting layer sectionthrough the ITO transparent electrode layers. The light-emitting devicealso has contact layers composed of In-containing GaAs, formed between the light-emitting layer sectionand the ITO transparent electrode layers, so as to contact with the ITO transparent electrode layers respectively. The contact layersare formed by annealing a stackobtained by forming GaAs layerson the light-emitting layer section, and by forming the ITO transparent electrode layersso as to contact with the GaAs layersto thereby allow In to diffuse from the ITO transparent electrode layersinto the GaAs layersThis provides a method of fabricating a light-emitting device, in which the ITO transparent electrode layers as the light-emission drive electrodes are bonded as being underlain by the contact layers, to thereby reduce contact resistance of these electrodes, and to thereby make the contact layers less susceptible to difference in the lattice constants with those of the light-emitting layer section during the formation thereof.

Method of fabricating light-emitting device and light-emitting device

Disclosed is a light-emitting device () has a light-emitting layer portion () which is composed of a group III-V compound semiconductor and a transparent thick-film semiconductor layer () with a thickness of not less than 40 &#x3bc;m which is formed on at least one major surface side of the light-emitting layer portion () and composed of a group III-V compound semiconductor having a band gap energy larger than the photon energy equivalent of the peak wavelength of emission flux from the light-emitting layer portion (). The transparent thick-film semiconductor layer () has a lateral surface portion (S) which is a chemically etched surface. The dopant concentration of the transparent thick-film semiconductor layer () is not less than 5&#xd7;10/cmand not more than 2&#xd7;10/cm. The light-emitting device can have a transparent thick-film semiconductor layer while being significantly improved in light taking-out efficiency from the lateral surface portion.

In the fabricating of a light emitting device, a light emitting layer portionand a current spreading layerrespectively composed of a Group III-V compound semiconductor, are stacked on a single crystal substrate. The light emitting layer portionis formed by a metal organic vapor-phase epitaxy process, and the current spreading layer, on such light emitting layer portion, is formed to have conductivity type of n-type by a hydride vapor-phase epitaxy process.

Method of fabricating a light emitting device, and light emitting device

In a light-emitting device, a light-emitting layer portion composed of a compound semiconductor is bonded on one main surface of a transparent conductive semiconductor substrate while placing a substrate-bonding conductive oxide layer composed of a conductive oxide in between. Between the light-emitting layer portion and the substrate-bonding conductive oxide layer, a contact layer for reducing junction resistance with the substrate-bonding conductive oxide layer so as to contact with the substrate-bonding conductive oxide layer. This is successful in providing the light-emitting device which is producible at low costs, has a low series resistance, and can attain a sufficient emission efficiency despite it has a thick current-spreading layer.

Light-emitting device and method of fabricating the same

A light emitting device capable of readily produce a pseudo-continuous spectrum covering a wide wavelength regions at low costs, and of totally solving various problems which have resided in the conventional light sources, and a lighting apparatus using this device is provided. The light emitting deviceis configured so that an active layer in a double hetero light emitting layer portion composed of compound semiconductors comprises a plurality of emission unit layers differing from each other in band gap energy, and so as to emit a simulatively synthesized light having a pseudo-continuous spectrum ensuring an emission intensity of 5% or more of a peak intensity over a wavelength region of 50 nm or more.

Light emitting device having a pseudo-continuous spectrum and lighting apparatus using the same

A light emitting device having an oxide transparent electrode layer as an emission drive electrode, and designed so that damage possibly occurs during bonding of electrode wires to the bonding pads is less influential to a light emitting layer portion is disclosed. The light emitting device has the light emitting layer portion composed of a compound semiconductor and has a double heterostructure in which a first-conductivity-type cladding layer, an active layer and a second-conductivity-type cladding layer are stacked in this order; and the light emitting layer portion is applied with emission drive voltage through an oxide transparent electrode layer formed so as to cover the main surface of the second-conductivity-type cladding layer. A bonding pad composed of a metal is disposed on the oxide transparent electrode layer, and to the bonding pad an electrode wire for current supply is bonded. Between the second-conductivity cladding layer and the oxide transparent electrode layer, a cushion layer composed of a compound semiconductor having a dopant concentration lower than that of the second-conductivity-type cladding layer is disposed.

A light emitting devicehas a structure in which a p type InGaAs layeras an electrode contact layer and an ITO electrode layeras an oxide transparent electrode layer are formed in the order in a first major surfaceside of a light emitting layer section. In a second major surfaceside of the light emitting layer section, an n type InGaAs layeras an electrode contact layer and an ITO electrode layeras an oxide transparent electrode layer are formed in the order. The ITO electrode layersandtogether with the p type InGaAs layerand the n type InGaAs layerare formed on the respective both major surfacesandof the light emitting layer sectionso as to cover the respective both major surfacesandin the entirety thereof.

The light-emitting device has an ITO electrode layer for applying drive voltage for light emission to a light emitting layer section , where the light from the light emitting layer section is extracted as being passed through the ITO electrode layer . Between the light emitting layer section and the ITO electrode layer , an electrode contact layer composed of In-containing GaAs is located so as to contact with such ITO electrode layer , where occupied areas and unoccupied areas for the electrode contact layer are arranged in a mixed manner on the contact interface with the transparent electrode layer . The electrode contact layer can be obtained by annealing a stack , which comprises a GaAs layer &Prime; formed on the light emitting layer section and the ITO electrode layer formed so as to contact with the GaAs layer &Prime;, to thereby allow In to diffuse from the ITO electrode layer to the GaAs layer

Light-emitting device and method for manufacturing the same

In the light emitting device having, a light emitting layer portion and a current spreading layer, respectively composed of a Group III-V compound semiconductor, formed on a single crystal substrate, the light emitting layer portion is formed on the single crystal substrate by the metal organic vapor-phase epitaxy process, and on such light emitting layer portion the current spreading layer is formed by the hydride vapor-phase epitaxy process. A high-concentration doped layer is also formed in a surficial area including the main surface on the electrode forming side of the current spreading layer, so as to have a carrier concentration of p-type dopant higher than that in the residual portion of the current spreading layer. A current blocking layer which comprises a Group III-V compound semiconductor having a conductivity type different from that of the current spreading layer is formed in the midway in the thickness-wise direction of the current spreading layer as being buried therein At least a portion of the current spreading layer covering the current blocking layer on the electrode side is formed by the hydride vapor-phase epitaxy process (the second vapor-phase growth step). The current spreading layer is composed of GaAs P (0.5&lE;a&lE;0.9). An off-angled substrate is available as the single crystal substrate.

Method of fabricating a light emitting device and light emitting device

By providing a nitrogen-doped low carrier concentration layer having both of a donor concentration and an acceptor concentration controlled below 1&times;10 /cm at a p-n junction portion between an n-type GaP layer and a p-type GaP layer the luminance of the GaP light emitting device can be improved by as much as 20 to 30% over the conventional one. Suppressing the donor concentration and the acceptor concentration in the low carrier concentration layer below 1&times;10 /cm inevitably gives a carrier concentration, which is expressed as a difference between both concentrations, lower than 1&times;10 /cm accordingly. The emission efficiency upon injection of electrons or holes can be improved by suppressing the concentration of the donor which serves as non-emissive center below 1&times;10 /cm to thereby extend the carrier lifetime; and by concomitantly suppressing the carrier concentration at a level significantly lower than that in the adjacent layers and

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Annaka, Japan

Masato Yamada