Kabushiki Kaisha Toshiba

Toshiba Electronic Devices & Storage Corporation

Other

Kabushiki Kasiha Toshiba

Hideto Sugawara

Masayuki Ishikawa

Koichi Nitta

Chisato Furukawa

Kazuhiko Itaya

Yukio Watanabe

Haruhiko Okazaki

Kuniaki Konno

Nobuhiro Suzuki

Yasuo Ohba

Yukie Nishikawa

Genichi Hatakoshi

Masaaki Onomura

Motoyuki Yamamoto

Kenji Isomoto

Mariko Suzuki

Hidetoshi Fujimoto

John Rennie

Yoshihiro Kokubun

Hirohisa Abe

Yoshiyuki Harada

Satoshi Komoto

Ryo Saeki

Yasuo Idei

Masanobu Iwamoto

Shinji Saito

Syotaro Ono

Johji Nishio

Hiroshi Ohta

Akira Tanaka

Masahiro Yamamoto

Takanobu Kamakura

Hiroaki Yamashita

Shinji Nunotani

Chie Hongo

Katsufumi Kondo

Hisao Ichijo

Tamotsu Jitosho

Lisa Sugiura

Shigeya Naritsuka

Kazuhiko Komatsu

Tsunenori Hiratsuka

Hiroaki Ootsuka

Toshiyuki Nishikawa

Minoru Watanabe

Hiroaki Yoshida

Masaki Okajima

Hajime Okuda

Hideo Shiozawa

Atsushi Kamata

Peter James Parbrook

Shozo Yuge

Kenichiro Kai

Nobuhir Suzuki

Niyoko Watanabe

Miyoko Watanabe

Naoki Murakami

A semiconductor light-emitting device includes a GaAs (gallium arsenide) substrate of a cubic crystal, a light-emitting layer and a multi-semiconductor layer. The light-emitting layer being provided on the GaAs substrate. The light-emitting layer includes InGaAs (indium gallium arsenide) represented by a compositional formula InxGa1-xAs (0<x<1). The multi-semiconductor layer being provided on a front surface of the GaAs substrate between the GaAs substrate and the light-emitting layer. The multi-semiconductor layer is tilted with respect to a (100) plane of the cubic crystal. The multi-semiconductor layer includes a first layer and a second layer. The first and second layers are alternately stacked in a direction perpendicular to the front surface of the GaAs substrate. The first layer is different in composition from the second layer.

Semiconductor light-emitting device and photocoupler

A semiconductor light-emitting device includes a substrate having a first energy bandgap, a first semiconductor layers on the substrate, an active layer on the first semiconductor layer, and a second semiconductor layer on the active layer. The active layer includes a quantum well layer, and a first barrier layer between the first semiconductor layer and the quantum well layer. The first semiconductor layer has a second energy bandgap wider than the first energy bandgap. The quantum well layer has a third energy bandgap narrower than the first and second energy bandgaps. The second semiconductor layer has a fourth energy bandgap wider than the third energy bandgap. The substrate has a refractive index greater than a refractive index of the first semiconductor layer. The refractive index of the first semiconductor layer is not less than a refractive index of the first barrier layer.

Semiconductor light-emitting device and optical coupling device

A semiconductor light-emitting device includes a semiconductor substrate and a light-emitting layer on the semiconductor substrate. The light-emitting layer includes at least one quantum well layer and barrier layers alternately stacked. The quantum well layer includes a first semiconductor mixed crystal having a larger lattice constant than a lattice constant of the semiconductor substrate. The barrier layers each includes a second semiconductor mixed crystal having a smaller lattice constant than the lattice constant of the semiconductor substrate. The quantum well layer includes a first strain amount that is a product of the layer thickness thereof and a first strain ratio. The barrier layer each includes a second strain amount that is a product of the layer thickness thereof and a second strain ratio. The quantum well layer and the barrier layers are provided such that the first strain amount is greater than the second strain amount.

Semiconductor light-emitting device

A semiconductor device includes an n-type semiconductor layer; a first metal layer provided on the n-type semiconductor layer, the first metal layer including first atoms capable of being n-type impurities in the n-type semiconductor layer; a second metal layer provided on the first metal layer, the second metal layer including titanium atoms; a third metal layer provided on the second metal layer; and a second atom capable of being a p-type impurity in the n-type semiconductor layer. The second atom and a part of the titanium atoms are included in a vicinity of an interface between the first metal layer and the second metal layer.

Semiconductor device and method for manufacturing the same

A semiconductor light-emitting device includes first and second semiconductor layers and a light-emitting layer provided between the first semiconductor layer and the second semiconductor layer. The first semiconductor layer includes a compound semiconductor represented by a compositional formula AlGaAs (0&#x3c;X&#x3c;1). The first semiconductor layer has an n-type conductivity and includes a first impurity of the n-type. The first layer further includes carbon with a lower concentration than a concentration of the first impurity, and oxygen with a lower concentration than the concentration of the first impurity. The second semiconductor layer includes a compound semiconductor represented by a compositional formula AlYGa1-YAs (0&#x3c;Y&#x3c;1). The second semiconductor layer has a p-type conductivity and including a second impurity of the p-type. The second semiconductor layer further includes carbon with a concentration substantially equal to the carbon concentration in the first semiconductor layer.

According to one embodiment, an optical semiconductor element includes a substrate, a light emitting layer, and a distributed Bragg reflector. The light emitting layer includes an AlGaAs multi quantum well layer. The distributed Bragg reflector is provided between the substrate and the light emitting layer. A pair of a first layer and a second layer is periodically stacked in the distributed Bragg reflector. The first layer includes AlGaAs. The second layer includes In(AlGa)P. A refractive index nof the first layer is higher than a refractive index nof the second layer. The first layer has a thickness larger than &#x3bb;0/(4n) where &#x3bb;0 is a center wavelength of a band on wavelength distribution of a reflectivity of the distributed Bragg reflector. The second layer has a thickness smaller than &#x3bb;0/(4n).

Optical semiconductor element

According to one embodiment, a semiconductor light emitting device includes a substrate, and a multi quantum well layer provided on the substrate, and including a plurality of barrier layers sandwiched between three or more InGaAs well layers and two InGaAs well layers. The barrier layers include at least two regions having different mixed crystal ratios or at least two regions having different thicknesses.

Semiconductor light emitting device

According to one embodiment, a semiconductor device includes first and second electrodes, first, second, third, fourth, fifth, sixth and seventh semiconductor regions, and a gate electrode. The first semiconductor region is provided on the first electrode. The second semiconductor region is provided on a portion of the first semiconductor region. The third semiconductor region is provided on another portion of the first semiconductor region. The fourth semiconductor region is provided in at least a portion between the first and third semiconductor regions. The fifth semiconductor region is provided between the first and fourth semiconductor regions. The sixth semiconductor region is provided on the third semiconductor region. The seventh semiconductor region is provided selectively on the sixth semiconductor region. The gate electrode opposes the second, sixth, and seventh semiconductor regions. The second electrode is provided on the sixth and seventh semiconductor regions.

Semiconductor device

A semiconductor device includes a semiconductor body, first and second electrodes, and a control electrode. The semiconductor body includes first to fourth semiconductor layers. The first electrode is provided on a front surface of the semiconductor body. The second electrode is provided on a back surface of the semiconductor body. The control electrode is provided between the semiconductor body and the first electrode. The second semiconductor layer is positioned between a portion and other portion of the first semiconductor layer in a first direction directed along the front surface. The third semiconductor layer contacts the portion of first semiconductor layer and the second semiconductor layer. The third semiconductor layer includes a first end portion positioned in the portion of the first semiconductor layer and a second end portion positioned in the second semiconductor layer. The fourth semiconductor layer is selectively provided in the second end portion.

A semiconductor light emitting device includes a supporting substrate, a light emitting layer including a nitride semiconductor, and a nitride multilayer film. The nitride multilayer film includes a first layer including a first nitride semiconductor containing aluminum nitride, a second layer including a second nitride semiconductor containing gallium nitride, and a third layer including the first nitride semiconductor containing aluminum nitride.

Semiconductor light emitting device and manufacturing method thereof

According to one embodiment, a method for fabricating a stacked nitride-compound semiconductor structure includes forming a first protection film on a second surface of a substrate, forming a first nitride-compound semiconductor layer on the first surface of the substrate, forming a second protection film on the first nitride-compound semiconductor layer, removing the first protection film to expose the second surface of the substrate, forming a second nitride-compound semiconductor layer on the second surface of the substrate, and removing the second protection film to expose the first surface of the second nitride-compound semiconductor layer.

Method for fabricating stacked nitride-compound semiconductor structure and method for fabricating nitride-compound semiconductor light emitting device

According to one embodiment, stacked layers of a nitride semiconductor include a substrate, a single crystal layer and a nitride semiconductor layer. The substrate does not include a nitride semiconductor and has a protrusion on a major surface. The single crystal layer is provided directly on the major surface of the substrate to cover the protrusion, and includes a crack therein. The nitride semiconductor layer is provided on the single crystal layer.

Stacked layers of nitride semiconductor and method for manufacturing the same

According to one embodiment, a nitride semiconductor stacked structure having a first surface includes a substrate, a first buffer layer, a first crystal layer, a second buffer layer and a second crystal layer. A step portion is provided in the substrate and includes an upper surface, a lower surface, and a side surface between the upper surface and the lower surface. The first buffer layer includes InAlGaN (0&#x2266;s&#x2266;0.05, 0&#x2266;t&#x2266;1) and covers the lower surface and the side surface. The first crystal layer is provided on the first buffer layer, includes InAlGaN (0&#x2266;s&#x2266;0.05, 0&#x2266;t&#x2266;0.05), and has an upper surface provided above the upper surface of the substrate. The second buffer layer includes InAlGaN (0&#x2266;s&#x2266;0.05, 0&#x2266;t&#x2266;1) and continuously covers the upper surface of the first crystal layer and the upper surface of the substrate. The second crystal layer covers the second buffer layer, includes InAlGaN (0&#x2266;s&#x2266;0.05, 0&#x2266;t&#x2266;0.05), and has the first surface.

Nitride semiconductor stacked structure and method for manufacturing same and nitride semiconductor device

Growing community of inventors

Kawasaki, Japan

Hideto Sugawara