Sharp Kabushiki Kaisha Corporation

Atsuo Tsunoda

Masahiro Hosoda

Kosei Takahashi

Takahiro Suyama

Sadayoshi Matsui

Mayuko Fudeta

Kentaro Tani

Yasuo Kan

Masanori Watanabe

Hiroshi Hayashi

Hiroyuki Hosoba

Masafumi Kondo

Tadashi Takeoka

Masahiko Sakata

Akiyoshi Sugahara

A nitride semiconductor light emitting device includes a conductive substrate, a first metal layer, a second conductivity-type semiconductor layer, an emission layer, and a first conductivity-type semiconductor layer in this order. The nitride semiconductor light emitting device additionally has an insulating layer covering at least side surfaces of the second conductivity-type semiconductor layer, the emission layer and the first conductivity-type semiconductor layer. A method of manufacturing the same is provided. The nitride semiconductor light emitting device may further include a second metal layer. Thus, a reliable nitride semiconductor light emitting device and a method of manufacturing the same are provided in which short-circuit at the PN junction portion and current leak is reduced as compared with the conventional examples.

Nitride semiconductor light emitting device

A semiconductor light emitting element including a conductive substrate, a bonding metal layer formed on the conductive substrate, a barrier layer formed on the bonding metal layer, a reflective layer formed on the barrier layer, an ohmic electrode layer formed on the reflective layer, a second conductivity type semiconductor layer formed on the ohmic electrode layer, a light emitting layer formed on the second conductivity type semiconductor layer, and a first conductivity type semiconductor layer formed on the light emitting layer, wherein outer peripheries of the second conductivity type semiconductor layer, the light emitting layer, and the first conductivity type semiconductor layer are removed, and a method of manufacturing the same are provided.

Semiconductor light emitting element and method of manufacturing the same

A method for manufacturing a semiconductor laser device is provided in which deformation of a cap layer and a third cladding layer is inhibited and a protruding portion of an intermediate layer is removed. By coating outer peripheral portions facing an intermediate layer of a third cladding layer and an etching stop layer with a resist, inevitably removing at least the third cladding layer, and etching the intermediate layer and a cap layer in a second etching step, a protruding portion of the intermediate layer is removed, and the cap layer is prevented from being etched undesirably, whereby a ridge portion without irregularities with respect to a direction substantially perpendicular to a lamination direction is produced, and increase of an operation voltage and decrease of external differential quantum efficiency are prevented.

Method for manufacturing semiconductor laser device

In this semiconductor laser device, an InGaP etching block layeras an etching selection layer having etching selectivity for an n-type AlInP current block layer, which is a non-optical-absorption layer, is formed on the n-type current block layer. Since this etching block layerprevents the current block layeron both sides of a ridgefrom being etched during manufacture, a contact layercan be prevented from entering gaps between the sides of this ridgeand the current block layer. Therefore, light oscillating in an active layeris taken out from a device end surface without being absorbed in the contact layer. According to this semiconductor laser device, an oscillation threshold current and an operation current can be maintained low, deterioration of differential quantum efficiency can be prevented and reliability can be improved.

Semiconductor laser device capable of maintaining the operation current low and method of manufacturing the same

A ridge section constructed of a p-type second AlGaInP clad layer, a p-type GaInP interlayerand a p-type GaAs cap layeris formed on an etching stop layer. A step of not smaller than 0.13 &#x3bc;m is formed between the p-type interlayerand the p-type second clad layerby making the p-type interlayerprotrude in both widthwise directions beyond the p-type second clad layer. With this step, AlInP layers can be formed separately from each other on both sides of the ridge section and on the ridge section. Therefore, when the AlInP layer on the ridge section is removed by etching, an AlInP current constriction layerlocated on both sides of the ridge section is reliably protected by a resist film and not over-etched. The AlInP current constriction layereffectively puts a current constriction function into effect, so that a semiconductor laser device of low-threshold current and low-power consumption is obtained.

Semiconductor laser device capable of preventing a threshold current and an operating current from increasing and manufacturing method therefor

The present invention relates to a ridge-stripe semiconductor laser device and a process for producing the same. More specifically, the object of the present invention is to control the formation of cavities at the side of the ridge without adding any step, and to provide a ridge stripe semiconductor laser device with good properties by strictly controlling its ridge width and a process for producing the same. Thereby, it is possible to form a ridge whose sidewalls stand almost vertically.

Semiconductor laser device and process for producing the same

By using a single semiconductor laser device, laser beams in infrared and red regions are generated at a distance between close light emitting spots. A semiconductor laser resonator having an oscillation wavelength in an infrared region and a semiconductor laser resonator having an oscillation wavelength in a red region are formed in parallel on the same semiconductor substrate.

Semiconductor device with multiple laser resonators

An object of the present invention is provide an InGaAlP-based semiconductor layer of a good crystal quality at a higher temperature up to a re-evaporating temperature by MBE process. A buffer layer made of GaAs and a buffer layer made of GaInP are formed by MBE (molecular beam epitaxy) process on a GaAs substrate having a facet, which is to be a main facet, inclined by &thgr; in &lsqb;011&rsqb; direction from (100) facet. Then semiconductor layers are formed by MBE process so as to include cladding layers having a bandgap E and an AlGaInP active layer having a bandgap E which is adjusted by an amount of III-group element to be represented by E <E . The semiconductor laser device has a ridge stripe extending in &lsqb;01-1&rsqb; direction.

Semiconductor laser device and a method for fabricating the same

On a GaAs substrate (Al.sub.Y Ga.sub.1-Y).sub.0.5 In.sub.0.5 P crystal layers (0.ltoreq.Y.ltoreq.1) is formed to be lattice-matched with the substrate. By radiating As molecular beams on the surface of the crystal layers while heating the layered substrate to a temperature at which In in the crystal layers evaporates, the portion near the surface of the crystal layers is changed into an Al.sub.Y Ga.sub.1-Y As crystal layer (0.ltoreq.Y.ltoreq.1) of a thickness of several molecules, on which layer an Al.sub.X Ga.sub.1-X As crystal layer (0.ltoreq.X.ltoreq.1) is formed. Since the surface of the Al.sub.Y Ga.sub.1-Y As crystal layer has been purl fled, the formed Al.sub.X Ga.sub.1-X As crystal layer has a high crystallinity, allowing production of a light emitting diode, a semiconductor laser device and the like with high efficiency.

Semiconductor laser device, and a method for producing a compound

A semiconductor laser device includes a substrate; a double hetero structure having an n-type cladding layer, an active layer, and a p-type cladding layer, which is formed on an upper face of the substrate; and electrodes formed on a lower face of the substrate and on an upper face of the double hetero structure, wherein the double hetero structure further includes a p-type hetero-barrier layer formed between the p-type cladding layer and the active layer, which is strained by compression due to a lattice mismatch.

Semiconductor laser device with compressively stressed barrier layer

A method for fabricating an AlGaInP semiconductor light emitting device having a substrate and a multilayer structure including an AlGaInP first semiconductor layer formed on the substrate. The method comprises the steps of removing part of the multilayer structure so that the first semiconductor layer is exposed, irradiating with plasma beams an oxide film formed on the exposed first semiconductor layer with the substrate temperature being kept at 500.degree. C. or less, so as to remove the oxide film from the first semiconductor layer and growing a second semiconductor layer on the first semiconductor layer.

Method for fabricating an AlGaInP semiconductor light emitting device

On a GaAs substrate (Al.sub.Y Ga.sub.1-Y).sub.0.5 In.sub.0.5 P crystal layers (0.ltoreq.Y.ltoreq.1) is formed to be lattice-matched with the substrate. By radiating As molecular beams on the surface of the crystal layers while heating the layered substrate to a temperature at which In in the crystal layers evaporates, the portion near the surface of the crystal layers is changed into an Al.sub.Y Ga.sub.1-Y As crystal layer (0.ltoreq.Y.ltoreq.1) of a thickness of several molecules, on which layer an Al.sub.X Ga.sub.1-X As crystal layer (0.ltoreq.X.ltoreq.1) is formed. Since the surface of the Al.sub.Y Ga.sub.1-Y As crystal layer has been purified, the formed Al.sub.X Ga.sub.1-X As crystal layer has a high crystallinity, allowing production of a light emitting diode, a semiconductor laser device and the like with high efficiency.

A semiconductor device comprising a (111)B single-crystalline semiconductor substrate which is misoriented toward (110), and epitaxial layers grown on the substrate by molecular beam epitaxy, whereby the crystallinity and luminescence efficiency of epitaxial layers are significantly improved.

Growing community of inventors

Higashihiroshima, Japan

Atsuo Tsunoda