Kabushiki Kaisha Toshiba

Ryo Saeki

Katsufumi Kondo

Hideto Sugawara

Yukio Watanabe

Masanobu Iwamoto

Masayuki Ishikawa

Takafumi Nakamura

Tamotsu Jitosho

Kazumi Unno

Katsuhiko Nisitani

Koichi Nitta

Yasuhiko Akaike

Hideki Nozaki

Yasuo Idei

Yoshinori Natsume

A light emitting device includes a stacked body including at least a light emitting layer made of In(AlGa)P(0&#x2266;x&#x2266;1, 0&#x2266;y&#x2266;1), a p-type cladding layer made of In(AlGa)P (0&#x2266;x&#x2266;1, 0&#x2266;y&#x2266;1), and a bonding layer made of a semiconductor; and a substrate in which deviation in a lattice constant at a bonding interface with the bonding layer is larger than deviation in lattice constants between the light emitting layer and the bonding layer. The p-type cladding layer is located more distant from the bonding interface than the light emitting layer, and the p-type cladding layer has a carrier concentration of 0.5&#xd7;10cmor more and 3&#xd7;10cmor less.

Light emitting device

A method for producing a light-emitting device, includes: performing, on a first substrate made of III-V group compound semiconductor, crystal growth of a laminated body including an etching easy layer contiguous to the first substrate and a light-emitting layer made of nitride semiconductor; bonding a second substrate and the laminated body; and detaching the second substrate provided with the light-emitting layer from the first substrate by, one of removing the etching easy layer by using a solution etching method, and removing the first substrate and the etching easy layer by using mechanical polishing method.

Light-emitting device and method for producing light emitting device

A semiconductor light emitting device includes: an upper growth layer including a light emitting layer; a transparent substrate through which a radiant light from the light emitting layer passes; and a foundation layer provided between the upper growth layer and the transparent substrate, the foundation layer having a surface-controlling layer and a bonding layer bonded with the transparent substrate. The surface-controlling layer is made of compound semiconductor including at least Ga and As. The upper growth layer is formed on an upper surface of the surface-controlling layer. A lattice constant difference at an interface between the surface-controlling layer and the upper growth layer is smaller than that at an interface between the bonding layer and the transparent substrate.

Semiconductor light emitting device and method for manufacturing same, and epitaxial wafer

A light emitting device includes a stacked body including at least a light emitting layer made of In(AlGa)P (0&#x2266;x&#x2266;1, 0&#x2266;y&#x2266;1), a p-type cladding layer made of In(AlGa)P (0&#x2266;x&#x2266;1, 0&#x2266;y&#x2266;1), and a bonding layer made of a semiconductor; and a substrate in which deviation in a lattice constant at a bonding interface with the bonding layer is larger than deviation in lattice constants between the light emitting layer and the bonding layer. The p-type cladding layer is located more distant from the bonding interface than the light emitting layer, and the p-type cladding layer has a carrier concentration of 0.5&#xd7;10cmor more and 3&#xd7;10cmor less.

A method for manufacturing a light emitting device, includes: forming a first multilayer body including a first substrate, a first semiconductor layer provided on the first substrate and having a light emitting layer, and a first metal layer provided on the first semiconductor layer; forming a second multilayer body including a second substrate having a thermal expansion coefficient different from a thermal expansion coefficient of the first substrate, and a second metal layer provided on the second substrate; a first bonding step configured to heat the first metal layer and the second metal layer being in contact with each other; removing the first substrate after the first bonding step; and a second bonding step configured to perform, after the removing, heating at a temperature higher than a temperature of the first bonding step.

Method for manufacturing light emitting device

A semiconductor light-emitting device, including a first substrate of a first conductivity type, a first bonding layer provided on the first substrate and consisting essentially of a GaP material of the first conductivity type, a second bonding layer provided on the first bonding layer, coincident with the first bonding layer in the planar direction of the crystal, having the first conductivity type, and consisting essentially of a material represented by a formula InGaP, where 0&#x2266;x, y&#x2266;1, and x+y=1, and a light-emitting layer comprising a first cladding layer, an active layer, and a second cladding layer, which are successively provided on the second bonding layer, each of the active layer and first and second cladding layers consisting essentially of a material represented by a formula InGaAlP, where x+y+z=1, and 0&#x2266;x, y, z&#x2266;1.

Semiconductor light-emitting device and method of manufacturing the same

A semiconductor light-emitting device, including a first substrate of a first conductivity type, a first bonding layer provided on said first substrate and consisting essentially of a GaP material of the first conductivity type, a second bonding layer provided on the first bonding layer, coincident with the first bonding layer in a crystal orientation, having the first conductivity type, and consisting essentially of a material represented by a formula In Ga P, where 0&lE;x, y&lE;1, and x&plus;y&equals;1, and a light-emitting layer comprising a first cladding layer, an active layer, and a second cladding layer, which are successively provided on the second bonding layer, each of the active layer and first and second cladding layers consisting essentially of a material represented by a formula In Ga Al P, where x&plus;y&plus;z&equals;1, and 0&lE;x, y, z&lE;1.

Semiconductor light-emitting device

A semiconductor light emitting element is proposed that improves a light extraction efficiency without requiring any complicated processes and techniques. The semiconductor light emitting element includes an active layer for emitting first light by current injection, and a light absorbing and emitting section for absorbing a part of the first light and for emitting second light having a greater peak wavelength than the first light. A difference in peak wavelength between the first light and the second light is in a range in which a spectrum of a mixture of the first and second light maintains a unimodal characteristic or is smaller than 0.9 times a half width of the spectrum of the first light.

Semiconductor light emitting element

A semiconductor light emitting device has a substrate made of a semiconductor of a first conductivity-type, a first light reflecting layer made of a semiconductor of the first conductivity-type and provided on a main surface of the substrate, an active layer made of a semiconductor including InGaAlP and provided on the first reflecting layer, a second light reflecting layer made of a semiconductor of a second conductivity-type and provided on the active layer, a current blocking layer having an opening, only through the opening a current flowing into the active layer, a transparent electrode provided on the second light reflecting layer, a front surface electrode provided on the transparent electrode and having an opening through which emission from the active layer is extracted; and a rear surface electrode provided on a rear surface of the substrate. The current supplied by the transparent electrode located under the opening of the front surface electrode and flowing into the active layer through the opening of the current blocking layer causes the active layer to emit light, the light being reflected repeatedly between the first and the second light reflecting layers and extracted via the transparent electrode under the opening of the front surface electrode.

Semiconductor light emitting device

In a semiconductor light emitting element using InGaAlP semiconductors, reduced in operative voltage and increased in optical output, a contact layer doped with a predetermined amount of carbon is provided to reduce the contact resistance at the contact with an ITO electrode because carbon does not readily diffuse like zinc and does not deteriorate the element characteristics. An intermediate band gap layer having an intermediate band gap between those of a contact layer and a cladding layer may be interposed between these layers to alleviate band discontinuity between their valence bands, thereby promote inflow of holes and decrease the element resistance.

A semiconductor light emitting device has a double heterostructure. The device is composed of an active layer and clad layers that sandwich the active layer. At least one of the clad layers has a multilayer structure having at least two element layers. The Al mole fraction of an element layer, which is proximal to the active layer, of the multilayer structure is smaller than that of the other element layer thereof distal from the active layer. This arrangement improves the crystal quality of an interface between the active layer and the clad layer of multilayer structure and effectively confines carriers in the active layer.

Led display device

A current blocking layer (7) formed immediately below a transparent electrode (9) is formed of a semiconductor layer containing Al, and a bandgap equal to or longer than the emission wavelength. Since the current blocking layer (7) is formed of such semiconductor layer, an oxide film forms on or near the surface of the current blocking layer (7) in a process of forming the transparent electrode (9) such as an ITO film containing oxygen, and the current blocking layer functions effectively. The diameter of a bonding electrode (20) is set to be smaller than that of the current blocking layer (7), thus effectively outputting the light emitted. Furthermore, the oxidized current blocking layer can have a high breakdown voltage and, hence, can be formed to have a small thickness, thus improving step coverage upon forming the transparent electrode on the current blocking layer. By inserting a thin Zn layer (8) between the transparent electrode (9) and an ohmic layer (6), the adhesion therebetween can be improved.

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Tokyo, Japan

Ryo Saeki