Showa Denko K.k.

Toyoda Gosei Co., Ltd.

Showa Denka K.k.

Munetaka Watanabe

Noritaka Muraki

Hisayuki Miki

Yasushi Ohno

Koji Kamei

Takehiko Okabe

Daisuke Hiraiwa

Remi Ohba

Nobuo Eitoh

Yasushi Ohono

A semiconductor light-emitting element including a substrate, a laminated semiconductor layer including a light-emitting layer formed over the substrate, one electrode () formed over the upper face of the laminated semiconductor layer, and an other electrode formed over the exposed surface of the semiconductor layer, from which the laminated semiconductor layer is partially cut off. The one electrode () includes a junction layer () and a bonding pad electrode () formed to cover the junction layer. The bonding pad electrode has a maximum thickness larger than that of the junction layer, and is composed of one or two or more layers. Slopes (), () and (), which are made gradually thinner toward the outer circumference, are formed in the outer circumference portions () and () of the junction layer and the bonding pad electrode. Also disclosed is a method for manufacturing the element and a lamp.

Semiconductor light-emitting element, electrode and manufacturing method for the element, and lamp

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 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

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.

Gallium nitride-based compound semiconductor light-emitting device

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

Munetaka Watanabe