Showa Denko K.k.

Showa Denka K.k.

Noritaka Muraki

Hisayuki Miki

Munetaka Watanabe

Mineo Okuyama

Takashi Udagawa

Hironao Shinohara

Noriyoshi Seo

Noriyuki Aihara

Yasushi Ohno

Ryouichi Takeuchi

Koji Kamei

Hiroshi Osawa

Hideki Tomozawa

Naoki Fukunaga

Yasushi Ohono

Nobuo Eitoh

Soichiro Masuyama

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 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.

A gallium nitride-based compound semiconductor light-emitting device including a positive electrode having openings, which is excellent in light extraction efficiency. The gallium nitride-based compound semiconductor light-emitting device includes a substrate; an n-type semiconductor layer, a light-emitting layer, and a p-type semiconductor layer, the layers being formed of a gallium nitride-based compound semiconductor and being stacked in this order on the substrate; a positive electrode which is provided so as to contact the p-type semiconductor layer; and a negative electrode which is provided so as to contact the n-type semiconductor layer, where the positive electrode is a positive electrode having openings, and at least a portion of the surface of the p-type semiconductor layer corresponding to the openings are roughened surface derived from spherical particulates.

Gallium nitride-based compound semiconductor light-emitting device

An object of the present invention is to provide a gallium nitride-based compound semiconductor light emitting device having excellent light extraction efficiency and a high emission output in which a planar shape is a rectangular shape with vertical and longitudinal sides each having a different length. The present light emitting device comprises a substrate and a gallium nitride-based compound semiconductor layer formed on the substrate, wherein a planar shape is a rectangular shape with vertical and longitudinal sides each having a different length, and a side surface of the gallium nitride-based compound semiconductor layer is not vertical to a principal surface of the substrate.

Gallium nitride-based compound semiconductor light emitting device

An object of the present invention is to provide a transparent positive electrode for use in a face-up-type chip which can emit intense light even using a low drive voltage. The inventive positive electrode for a semiconductor light-emitting device comprises a transparent electrode formed on a semiconductor layer and a bonding pad electrode formed on the transparent electrode, wherein the bonding pad electrode has a reflecting layer that is in contact with at least the transparent electrode.

Positive electrode for semiconductor light-emitting device

This gallium nitride-based compound semiconductor light emitting device includes an n-type semiconductor layer, a light emitting layer, and a p-type semiconductor layer that are composed of gallium nitride-based compound semiconductors and are deposited in that order on a substrate, and further includes a negative electrode and a positive electrode that are in contact with the n-type semiconductor layer and the p-type semiconductor layer, respectively, wherein the positive electrode has a translucent electrode composed of a three-layer structure including a contact metal layer that contacts at least the p-type semiconductor layer, a current diffusion layer provided on the contact metal layer and having conductivity greater than that of the contact metal layer, and a bonding pad layer provided on the current diffusion layer, and a mixed positive electrode-metal layer including a metal that forms the contact metal layer is present in a positive electrode side surface of the p-type semiconductor layer.

An object of the present invention is to provide a gallium nitride-based compound semiconductor light emitting device having superior light extraction efficiency and light distribution uniformity. The inventive gallium nitride-based compound semiconductor light emitting device comprises a substrate and a gallium nitride-based compound semiconductor layer stacked on the substrate, wherein on at least one lateral surface of the light emitting device, the bottom (substrate side) of the semiconductor layer is a reverse taper inclined 5 to 85 degrees relative to the substrate main surface and the top of the semiconductor layer is a forward taper inclined 95 to 175 degrees relative to the substrate main surface.

The invention provides a gallium nitride based compound semiconductor light emitting device with excellent light extracting efficiency and its production method. A light emitting device, obtained from a gallium nitride based compound semiconductor, includes a substrate; a n-type semiconductor layer, a light emitting layer, and a p-type semiconductor layer, sequentially stacked on a substrate; a light-permeable positive electrodestacked on the p-type semiconductor layer; a positive electrode bonding padprovided on the light-permeable positive electrode; and a negative electrode bonding pad providedon the n-type semiconductor layer, wherein a disordered uneven surface formed at least on a part of the surfaceof the p-type semiconductor layer

Gallium nitride-based compound semiconductor light-emitting device and production method thereof

An object of the present invention is to provide a positive electrode having high transparency, low contact resistance and excellent current diffusibility and not requiring electron beam irradiation, high-temperature annealing or heat treatment, for alloying, in an oxygen atmosphere. The inventive transparent positive electrode for gallium nitride-based compound semiconductor light-emitting devices comprises a contact metal layer in contact with a p-type semiconductor layer, a current diffusing layer on the contact metal layer, the current diffusing layer having an electrical conductivity larger than that of the contact metal layer, and a bonding pad layer on the current diffusing layer.

Transparent positive electrode

It is an object of the present invention to provide a gallium nitride-based compound semiconductor light-emitting device that is excellent in light output efficiency and needs only a low driving voltage (Vf). The inventive gallium nitride-based compound semiconductor light-emitting device includes an n-type semiconductor layer, a light-emitting layer and a p-type semiconductor layer formed of a gallium nitride-based compound semiconductor and stacked in this order on a substrate, and positive and negative electrodes so arranged as to be in contact with the p-type semiconductor layer and the n-type semiconductor layer, respectively, wherein a region in which a p-type impurity and hydrogen atoms are co-present exists in the p-type semiconductor layer in contact with the positive electrode, and at least a portion, which is in contact with the p-type semiconductor layer, of the positive electrode, is formed of an n-type electro-conductive light transmitting material.

A transparent electrode for a gallium nitride-based compound semiconductor light-emitting device includes a p-type semiconductor layer (), a contact metal layer () formed by ohmic contact on the p-type semiconductor layer, an current diffusion layer () formed on the contact metal layer and having a lower magnitude of resistivity on the plane of the transparent electrode than the contact metal, and a bonding pad () formed on the current diffusion layer. The transparent electrode is at an advantage in widening the surface of light emission in the p-type semiconductor layer, decreasing the operation voltage in the forward direction, and enabling the bonding pad to provide excellent adhesive strength.

Transparent electrode for semiconductor light-emitting device

The inventive gallium nitride compound semiconductor light-emitting device comprises a substrate; an n-type semiconductor layer, a light-emitting layer, a p-type semiconductor layer, the layers being successively provided atop the substrate and being formed of a gallium nitride compound semiconductor; a negative electrode provided on the n-type semiconductor layer at a certain portion thereof, the portion being exposed by partial, depthwise removal of the light-emitting layer and the p-type semiconductor layer altogether through reactive ion etching; and a positive electrode provided on the remaining p-type semiconductor layer, wherein the gallium nitride compound semiconductor light-emitting device is produced through reactive ion etching by use of silicon tetrachloride as the sole etching gas.

An object of the present invention is to provide a light-permeable electrode for use in a gallium nitride-based compound semiconductor light-emitting device, the electrode having improved light permeability and contact resistance. The inventive electrode comprises a light-permeable first layer which is in contact with a surface of a p-contact layer in a gallium nitride-based compound semiconductor light-emitting device and which is capable of providing ohmic contact, and a second layer which is in contact with a part of a surface of said p-contact layer, wherein the first layer comprises a metal, or an alloy of two or more metals, selected from a first group consisting of Au, Pt, Pd, Ni, Co, and Rh, and the second layer comprises an oxide of at least one metal selected from a second group consisting of Ni, Ti, Sn, Cr, Co, Zn, Cu, Mg, and In.

Gallium nitride-based compound semiconductor light-emitting device and electrode for the same

A transparent electrode for use in a gallium nitride-based compound semiconductor light-emitting device having an emission wavelength of 440 nm or less, includes a metal layer disposed in contiguity to a p-type semiconductor layer and a current diffusion layer disposed on the metal layer. The transparent electrode contains substantially no Au in the whole region thereof. The metal layer contains any one element selected from the group consisting of Pt, Ir, Ru and Rh as a main component. The current diffusion layer contains any one element selected from the group consisting of Pt, Ir, Ru and Rh as a main component except for the case where the metal layer and the current diffusion layer have the same composition. It is possible to provide a white light-emitting device provided with the transparent electrode, a white light-emitting lamp using the white light-emitting device and a lighting fixture using the white light-emitting lamp.

Growing community of inventors

Ichihara, Japan

Noritaka Muraki