Rohm Co., Ltd.

Rohm Gmbh

Yukio Shakuda

Shunji Nakata

Yukio Matsumoto

Masayuki Sonobe

Haruo Tanaka

Tsuyoshi Tsutsui

Norikazu Itoh

Nobuaki Oguro

Masato Mushiage

Tatsuo Yamauchi

Toshio Nishida

Katsuhiko Ikawa

Hiroshi Matagi

A semiconductor light emitting device of double hetero junction includes an active layer and clad layers. The clad layers include an n-type layer and p-type layer. The clad layers sandwich the active layer. A band gap energy of the clad layers is larger than that of the active layer. The band gap energy of the n-type clad layer is smaller than of the p-type clad layer.

Semiconductor light emitting device and manufacturing method therefor

The present invention provides a method of manufacturing a nitride semiconductor capable of improving the crystallinity and the surface state of the nitride semiconductor crystal formed on top of a high-temperature AlN buffer layer. An AlN buffer layer is formed on top of a growth substrate, and then nitride semiconductor crystals are grown on top of the AlN buffer layer. In a stage of manufacturing the nitride semiconductor, the crystal of the AlN buffer layer is grown at a high temperature of 900&#xb0; C. or higher. In addition, an Al-source material of the AlN buffer layer is started to be supplied first to a reaction chamber and continues to be supplied without interruption, and then a N-source material is supplied intermittently.

Method of manufacturing nitride semiconductor and nitride semiconductor element

A GaN related compound semiconductor element includes: a channel layer made of a GaN related compound semiconductor; and a source layer and a drain layer, which are disposed in a manner of sandwiching the channel layer. The source layer includes two adjacent ridge portions which are formed by selective growth. A source electrode is formed over the surface, sandwiched by the ridge portions, of the channel layer, and the surfaces of the respective two adjacent ridge portions. The selective-growth mask formed between the two ridge portions is removed by wet etching. In addition, as another embodiment, a gate electrode is formed in a manner that the direction of the longer dimension of the gate electrode is aligned with the m plane of the channel layer. Moreover, as still another embodiment, the channel layer has a multilayer structure in which a GaN layer doped with no impurity is used as an intermediate layer.

GaN related compound semiconductor element and process for producing the same and device having the same

The present invention provides a nitride semiconductor light-emitting device capable of preventing shortening of the device lifetime due to increase in the driving voltage of the device and internal heat generation, and also providing uniform laser characteristics, even if the device has a ridge stripe structure. On a GaN substrate, an n-type GaN layer, an n-type AlGaN layer, an active layer, a p-type AlGan layerand a p-type GaN layerare laminated sequentially. On the p-type GaN layer, an insulating filmand a transparent electrodeare formed. A portion of the transparent electrodeis formed in contact with the p-type GaN layer. A ridge stripe portion D to form a waveguide is configured of a transparent film. A region, where the transparent electrodeand the p-type GaN layerare in contact with each other, serves as a stripe-shaped current injection region.

Semiconductor light-emitting device

Provided is a semiconductor light emitting device which includes a number of hexagon-shaped semiconductor light emitting elements formed two-dimensionally, and in which the positive electrodes and the negative electrodes are formed on its light outputting surface side lest the light outputting efficiency should decrease. A maskfor selective growth is formed on a substratefor growth, and an AlN buffer layeris formed in regions from each of which a part of the maskfor selective growth is removed. An undoped GaN layer, an n-type GaN layer, an active layerand a p-type GaN layerare sequentially stacked on the AlN buffer layer. An isolation groove A for isolating the elements from one another is formed. A p-electrodeand an n-electrodeof each semiconductor light emitting element D are formed on its hexagon-shaped light outputting surface side, and the p-electrodes or n-electrodes of each two neighboring semiconductor light emitting elements are arranged adjacent to each other with the isolation groove A in between.

Semiconductor light emitting device

A semiconductor light emitter (A) includes an n-type semiconductor layer (), a p-type semiconductor layer (), and an active layer () between these two layers (). The light emitter (A) further includes an n-side electrode () on the n-type layer () and a p-side electrode () on the p-type layer (). An insulating layer () covers the n-type and p-type layers (),(), while also partially covering the n-side and p-side electrodes (),(), leaving part of the electrodes () exposed. The n-side electrode () has a first Al layer () formed on the n-type layer () and a second Ni, W, Zr or Pt layer () formed on the first layer (). The p-side electrode () has a first Au layer () formed on the p-type layer (), and a second Ni, W, Zr or Pt layer () formed on the first layer ().

Semiconductor light emitting element and method for manufacturing same

To provide a method for manufacturing a semiconductor light emitting device capable of providing sufficiently low operating voltage. The method for manufacturing a semiconductor light emitting device of the present invention includes: a semiconductor laminating step of laminating a plurality of nitride semiconductor layers of to form a semiconductor laminating structure; and an electrode forming step of forming n-side electrode and p-side electrodes on the n-type and p-type semiconductor layers. In the electrode forming step, after a first metallic layer including a Ni layer constituting a part of the n-side electrode is formed on a surface of a forming region of the n-side electrode, the first metallic layer is annealed in an atmosphere containing nitrogen and oxygen.

Method for manufacturing a semiconductor light emitting device

There is provided a highly reliable semiconductor light emitting device even in using for street lamps or traffic signals, which can be used in place of electric lamps or fluorescent lamps by protecting from surges such as static electricity or the like. A plurality of light emitting units () are formed, by forming a semiconductor lamination portion by laminating semiconductor layers on a substrate so as to form a light emitting layer, by electrically separating the semiconductor lamination portion into a plurality, and by providing a pair of electrodes () and (). The light emitting units () are respectively connected in series and/or in parallel with wiring films (). An inductor () absorbing surges is connected, in series, to the plurality of light emitting units () connected in series between electrode pads () and () connected to an external power source. For an example, the inductor () is formed by arranging the plurality of light emitting units () in a whirl shape.

A nitride semiconductor device includes a semiconductor substrate; a first nitride semiconductor layer provided on the semiconductor substrate; a mask layer having opening portions, provided on the first nitride semiconductor layer; a second nitride semiconductor layer selectively grown on the mask layer laterally from the opening portions; and a semiconductor lamination portion formed by laminating nitride semiconductor layers so as to form a semiconductor element on the second nitride semiconductor layer. The substrate may be made of a zinc-based compound, the first nitride semiconductor layer may be provided on, and in contact with, the substrate, and at least a substrate side of the first nitride semiconductor layer may be made of AlGaN (0.05&#x2266;y&#x2266;0.2). Additionally, the semiconductor element may be a light emitting layer in which case the mask layer may include a metal film provided on the first nitride semiconductor layer and an insulating film provided on the metal film.

Nitride semiconductor device having a zinc-based substrate

As an example of a nitride semiconductor light emitting device, on a sapphire substrate, a GaN buffer layer, an n-type GaN contact layer, an MQW active layer, and a p-type GaN contact layer are sequentially stacked, and a partial region from the p-type GaN contact layer to the middle of the n-type GaN contact layer is mesa-etched so as to form an n electrode. Meanwhile, a p electrode is provided on the p-type GaN contact layer, and, in addition to the p electrode, multiple ridge parts are formed by crystal growth so as to be scattered. By providing the multiple ridge parts, device characteristics can be improved without causing damage on the GaN-based semiconductor layer.

Nitride semiconductor light emitting device having ridge parts

There is provided a nitride semiconductor light emitting device having high internal quantum efficiency by accelerating recombination radiation while employing a multiple quantum well structure in which each of well layers has a relatively large thickness. The nitride semiconductor light emitting device is provided with a nitride semiconductor lamination portion () provided on a substrate (). The nitride semiconductor lamination portion () includes at least an active layer () in which a light emitting portion is formed. And the active layer is constituted with a multiple quantum well structure formed by laminating well layers () made of InGaN (0&#x3c;x&#x2266;1), and barrier layers () made of AlInGaN (0&#x2266;y&#x3c;1, 0&#x2266;z&#x3c;1, 0&#x2266;y+z&#x3c;1, z&#x3c;x) alternately. In addition, one of the well layers is divided at least into a first well layer () and a second well layer () by a thin film barrier layer () made of AlInGaN (0&#x2266;v&#x3c;1, 0&#x2266;w&#x3c;1, 0&#x2266;v+w&#x3c;1, w&#x3c;x), and the thin film barrier layer is formed so as to have a thickness of one atomic layer or more and 20 Angstroms or less.

Nitride semiconductor light emitting device

A light emitting element group includes a plurality of light emitting element units connected in series. A first current limiting circuit is arranged in series with the light emitting element group, and limits a first drive current flowing from one end to the other end of the light emitting element group. A second current limiting circuit is arranged in parallel to the first current limiting circuit, and limits a second drive current flowing in an opposite direction to the first drive current in the light emitting element group. The light emitting element units are configured to include a first light emitting element and a second light emitting element; an anode of the first light emitting element and a cathode of the second light emitting element are connected, and an anode of the second light emitting element and a cathode of the first light emitting element are connected.

Light emitting device

A plurality of transistors are formed on a substrate in a plurality of columns. Each transistor has a first conductivity type region and second conductivity type regions provided on both sides thereof in a column direction, and has an active layer on the side of each second conductivity type region closer to the substrate. Between two columns adjacent to each other, the second conductivity type region on a first side in the column direction of each transistor arranged on a first column, the second conductivity type region on a second side in the column direction of the transistor adjacent to this transistor on the first side in the column direction and the first conductivity type region of each transistor arranged on a second column are electrically connected by a first wire. Between these two columns, the second conductivity type region on the first side in the column direction of each transistor arranged on the second column, the second conductivity type region on the second side in the column direction of the transistor adjacent to this transistor on the first side in the column direction and the first conductivity type region of each transistor arranged on the first column are electrically connected by a second wire.

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Kyoto, Japan

Yukio Shakuda