Showa Denko K.k.

Noriyoshi Seo

Atsushi Matsumura

Ryouichi Takeuchi

Noriyuki Aihara

Noritaka Muraki

Akira Uzawa

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

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

Disclosed is a light-emitting diode, which has a red and infrared emitting wavelength, excellent monochromatism characteristics, and high output and high efficiency and excellent humidity resistance. The light-emitting diode is provided with: a light-emitting section, which includes an active layer having a quantum well structure and formed by laminating alternately a well layer which comprises a composition expressed by the composition formula of (AlGa)As (0&#x2266;X1&#x2266;1) and a barrier layer which comprises a composition expressed by the composition formula of (AlGa)As (0&#x3c;X2&#x2266;1), and a first clad layer and a second clad layer, between both of which the active layer is sandwiched, wherein the first clad layer and the second clad layer comprise a composition expressed by the composition formula of (AlGa)InP (0&#x2266;X3&#x2266;1, 0&#x3c;Y1&#x2266;1); a current diffusion layer formed on the light-emitting section; and a functional substrate bonded to the current diffusion layer.

Light emitting diode, light emitting diode lamp, and illuminating apparatus

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

A light-emitting diode, including a light emitting section including an active layer having a quantum well structure in which well layers having the composition: (InGa)As (0&#x2266;X1&#x2266;1) and barrier layers having the composition: (AlGa)As (0&#x2266;X2&#x2266;1) are alternately laminated, first guide and second guide layers paired to sandwich the active layer and having the composition: (AlGa)As (0&#x2266;X3&#x2266;1), and first cladding and second cladding layers paired to sandwich the active layer via the first guide layer and the second guide layer, respectively; a current diffusion layer formed on the light emitting section; and a functional substrate bonded to the current diffusion layer; wherein the first cladding layer and the second cladding layer have the composition: (AlGa)InP (0&#x2266;X4&#x2266;1, 0&#x3c;Y&#x2266;1); and a light-emitting diode lamp and a lighting device using the same.

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

Disclosed is a light-emitting diode, which has a red and infrared emitting wavelength, excellent monochromatism characteristics, and high output and high efficiency and excellent humidity resistance. The light-emitting diode is provided with: a light-emitting section, which includes an active layer having a quantum well structure and formed by laminating alternately a well layer which comprises a composition expressed by the composition formula of (AlGa) As (0&#x2266;X&#x2266;1) and a barrier layer which comprises a composition expressed by the composition formula of (AlGa) As (0&#x3c;2&#x2266;1), and a first clad layer and a second clad layer, between both of which the active layer is sandwiched, wherein the first clad layer and the second clad layer comprise a composition expressed by the composition formula of (AlGa)InP (0&#x2266;X&#x2266;1, 0&#x3c;Y&#x2266;1); a current diffusion layer formed on the light-emitting section; and a functional substrate bonded to the current diffusion layer.

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.

Growing community of inventors

Hiki-gun, Japan

Noriyoshi Seo