Showa Denko K.k.

Atsushi Matsumura

Noriyoshi Seo

Ryouichi Takeuchi

Noriyuki Aihara

Takashi Watanabe

Akira Uzawa

Yu Tokunaga

Yuu Tokunaga

A method for manufacturing a tunnel junction layer using organic vapor phase deposition, the method including: a first process that supplies a first material gas containing a group III element, a second material gas containing a group V element, and a third material gas containing a dopant of a first conductivity type, onto a compound semiconductor layer on which the tunnel junction layer is to be laminated; a second process that stops supplying the first material gas, the second material gas and the third material gas, and supplies a fourth material gas containing a dopant of a second conductivity type opposite to the first conductivity type; and a third process that continues to supply the fourth material gas, and further supplies a fifth material gas containing a group III element and a sixth material gas containing a group V element.

Method for manufacturing tunnel junction layer

A light-emitting element layerincludes: an n-type contact layer; a first light-emitting layer; a tunnel junction layer; a second light-emitting layer; and a p-type contact layerlaminated in this order. The first light-emitting layerand the second light-emitting layeremit light of the same wavelength. The tunnel junction layerincludes: a p-type tunnel layermade of AlGaAs containing p-type impurities (C); and an n-type tunnel layermade of GaInP containing n-type impurities (Te). A highly n-type impurities-doped layerhaving a higher concentration of n-type impurities than the n-type tunnel layeris arranged between the p-type tunnel layerand the n-type tunnel layer

Light-emitting diode and method for manufacturing tunnel junction layer

Provided are a light-emitting diode which prevents degradation of reflectance and which enables high-luminosity light emission, and its manufacturing method. Such a light-emitting diode includes a substrate () upon which are provided, in this order, a reflecting layer (), a transparent film () wherein multiple ohmic contact electrodes () are embedded at intervals, and a compound semiconductor layer () including a current diffusion layer () and a light-emitting layer () in this order. The periphery of the surface of each ohmic contact electrode () on the substrate () side are covered by the transparent film (), and the ohmic contact electrodes () contact the reflecting layer () and the current diffusion layer ().

Light-emitting diode and method of manufacturing same

In a light-emitting diode, a plurality of dot-shaped ohmic contact electrodes are provided between a metal reflective film and a compound semiconductor layer, an ohmic electrode and a surface electrode composed of a pad portion and a plurality of linear portions connected to the pad portion are provided in that order on the opposite side of the compound semiconductor layer from the semiconductor substrate, the surface of the ohmic electrode is covered with the linear portions, the ohmic contact electrodes and the ohmic electrode are formed in positions that do not overlap with the pad portion in plan view, and among the plurality of ohmic contact electrodes, 5% or more and 40% or less of the ohmic contact electrodes are disposed in positions that overlap with the linear portions in plan view.

Light-emitting diode, light-emitting diode lamp, and illumination device

A light-emitting diode, a method of manufacturing the same, a lamp and an illumination device. A light-emitting diode () is provided with a compound semiconductor layer () including a light-emitting layer () provided on a substrate (); an ohmic contact electrode () provided between the substrate and compound semiconductor layer; an ohmic electrode () provided on the side of the compound semiconductor layer opposite the substrate; a surface electrode () including a branch section () provided so as to cover the surface of the ohmic electrode and a pad section () coupled to the branch section; and a current-blocking portion () provided between an under-pad light-emitting layer () arranged in an area of the light-emitting layer that overlaps the pad section () and a light-emitting layer arranged in an area except the area that overlaps the pad section, to prevent current from being supplied to the under-pad light-emitting layer.

Light-emitting diode, method for manufacturing light-emitting diode, light-emitting diode lamp and illumination device

The present invention relates to an epitaxial wafer for a light-emitting diode wherein the peak emission wavelength is 655 nm or more, and it is possible to improve reliability. The epitaxial wafer for light-emitting diodes includes a GaAs substrate () and a pn-junction type light-emitting unit () provided on the GaAs substrate (), wherein light-emitting unit () is formed as a multilayer structure in which a strained light-emitting layer and a barrier layer are alternately stacked, and the composition formula of the barrier layer is (AlGa)InP (0.3&#x2266;X&#x2266;0.7, 0.51&#x2266;Y&#x2266;0.54).

Epitaxial wafer for light-emitting diodes

The present invention relates to a light-emitting diode which has an emission wavelength of 655 nm or more, excellent monochromatic properties, high output, high luminance, high efficiency and fast response time, has such a characteristic that the intensity of light emitted from a light extraction surface and traveling in a direction perpendicular to the light extraction surface has high directivity, and can release heat to the outside with high efficiency; and a light-emitting diode lamp. The light-emitting diode includes a compound semiconductor layer () which includes at least a pn-junction-type light-emitting section () and a strain adjustment layer () laminated on the light-emitting section (); wherein the light-emitting section () has a laminated structure composed of a strained light-emitting layer having a composition formula (AlGa)InP (0&#x2266;X&#x2266;0.1, 0.37&#x2266;Y&#x2266;0.46) and a barrier layer, wherein the strain adjustment layer () can be penetrated by light from the light-emitting section () and has a smaller lattice constant than those of the strained light-emitting layer and the barrier layer; and wherein a functional substrate () is bonded to a surface () of the compound semiconductor layer () which is located on the opposite side with respect to the light extraction surface () through a reflective structure ().

Light-emitting diode and light-emitting diode lamp

A light emitting diode is provided by the present invention which includes a pn junction-type light emitting unit having a light emitting layer () composed of n layers of a strained light emitting layer () and n&#x2212;1 layers of a barrier layer (), wherein when a barrier layer exists, the light emitting layer () has a structure in which one strained light emitting layer () and one barrier layer () are laminated alternately, n represents an integer of 1 to 7, and the thickness of the light emitting layer () is not more than 250 nm.

Light emitting diode and light emitting diode lamp

A light emitting diode including a compound semiconductor layer having at least a pn junction-type light emitting unit and a strain adjustment layer stacked on the light emitting unit, wherein the light emitting unit has a stacked structure containing a strained light emitting layer having a composition formula of (AlGa)InP (wherein X and Y are numerical values that satisfy 0&#x2266;X&#x2266;0.1 and 0.39&#x2266;Y&#x2266;0.45 respectively) and a barrier layer, and the strain adjustment layer is transparent to the emission wavelength and has a lattice constant that is smaller than the lattice constants of the strained light emitting layer and the barrier layer. The light emitting diode has an emission wavelength of not less than 655 nm, exhibits excellent monochromaticity, high output and/or high efficiency, and has a fast response speed.

Light emitting diode, light emitting diode lamp and illuminating device

An epitaxial wafer for a light emitting diode, including a GaAs substrate, a light emitting unit provided on the GaAs substrate, and a strain adjustment layer provided on the light emitting unit, wherein the light emitting unit has a strained light emitting layer having a composition formula of (AlGa)InP (wherein X and Y are numerical values that satisfy 0&#x2266;X&#x2266;0.1 and 0.39&#x2266;Y&#x2266;0.45 respectively), and the strain adjustment layer is transparent to the emission wavelength and has a lattice constant that is smaller than the lattice constant of the GaAs substrate. The invention provides an epitaxial wafer that enables mass production of a high-output and/or high-efficiency LED having an emission wavelength of not less than 655 nm.

Epitaxial wafer for light emitting diode

A light-emitting diode includes a substrate, a compound semiconductor layer including a p-n junction-type light-emitting part formed on the substrate, an electric conductor disposed on the compound semiconductor layer and formed of an electrically conductive material optically transparent to the light emitted from the light-emitting part and a high resistance layer possessing higher resistance than the electric conductor and provided in the middle between the compound semiconductor layer and the electric conductor. In the configuration of a light-emitting diode lamp, the electric conductor and the electrode disposed on the semiconductor layer on the side opposite to the electric conductor across the light-emitting layer are made to assume an equal electric potential by means of wire bonding. The light-emitting diode abounds in luminance and excels in electrostatic breakdown voltage.

Light-emitting diode and method for fabrication thereof

A light emitting diode which includes a laminate including an n-type cladding layer, an emission layer which has a quantum well structure having a well layer and a barrier layer, an intermediate layer and a p-type cladding layer in this order, wherein the composition of each of the layers is represented by the composition formula: (AlGa)InP (0&#x2266;X&#x2266;1, 0&#x3c;Y&#x2266;1), and the composition of the barrier layer is represented by the composition formula: (AlGa)InP (0.5&#x2266;X&#x2266;1, 0&#x3c;Y&#x2266;1).

Growing community of inventors

Chichibu, Japan

Atsushi Matsumura