Abstract: On a GaAs substrate (1), are formed a DBR (Distributed Bragg Reflector) (3), and a light-emitting layer (5) made of a plurality of layers of AlyGazIn1-y-zP (0?y?1, 0?z?1) above the DBR (3). A semiconductor layer or a plurality of semiconductor layers (6)-(10) having a number of layers of 1 or more are formed on the light-emitting layer (5), and a grating pattern for scattering light is formed on a surface of the semiconductor layer (9) by photolithography and by etching with a sulfuric acid/hydrogen peroxide based etchant. Thus, a semiconductor device small in radiation angle dependence of light emission wavelength, as well as a manufacturing method therefor, are provided.

Abstract: An n-type AlAs/n-type Al0.5Ga0.5As DBR layer and a p-type (Al0.2Ga0.8)0.5In0.5P/p-type Al0.5In0.5P DBR layer are formed on an n-type GaAs substrate at specified intervals so that a reflection spectrum is centered at 650 nm and the resonance wavelength becomes 650 nm. A quantum well active layer (light-emitting layer) is formed so that the light emission peak wavelength becomes 650 nm in the belly position of the standing wave generated in a resonator constructed of both the DBR layers. A grating pattern is formed on the surface of a p-type Al0.5Ga0.5As light diffusion layer that serves as a light-emitting surface surrounded by a p-type electrode. By thus roughening the light-emitting surface, light emitted from the light-emitting layer is diffused in various directions, reducing the radiation angle dependency of the emission light wavelength.

Abstract: A semiconductor laser device, comprising a buffer layer of a first conductivity type, a clad layer of the first conductivity type, an active layer and a clad layer of a second conductivity type formed on a semiconductor substrate of the first conductivity type, wherein a band gap in the buffer layer of the first conductivity type has a value which is greater than a band gap of the semiconductor substrate and smaller than a band gap of the clad layer of the first conductivity type, and an impurity concentration in the buffer layer of the first conductivity type is higher than an impurity concentration in the clad layer of the first conductivity type.

Abstract: In this semiconductor laser device, an InGaP etching block layer 11 as an etching selection layer having etching selectivity for an n-type AlInP current block layer 10, which is a non-optical-absorption layer, is formed on the n-type current block layer 10. Since this etching block layer 11 prevents the current block layer 10 on both sides of a ridge 20 from being etched during manufacture, a contact layer 12 can be prevented from entering gaps between the sides of this ridge 20 and the current block layer 10. Therefore, light oscillating in an active layer 4 is taken out from a device end surface without being absorbed in the contact layer 12. 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.

Abstract: A semiconductor laser device of a III-V group compound includes a substrate including a main surface having an inclination angle of less than 20° toward a [011] direction from a (100) plane and an inclined facet further inclined toward the [011] direction from the main surface, a light emitting stacked-layered portion including at least an active layer and a clad layer over the substrate, and a current-constricting layer including a IV group impurity. The current-constricting layer has a region of an n type conductivity above the main surface of the substrate, and a region of a p type conductivity above the inclined facet of the substrate.

Abstract: A semiconductor light emitting device has in sequence on a semiconductor substrate, a multilayer reflection film, a semiconductor layer, and a quantum well active layer. A distance between an upper surface of the multilayer reflection film and a lower surface of the quantum well active layer is 2?/n or less, where ? is a light emission wavelength and n is an average refractive index of the semiconductor layer disposed in between the multilayer reflection film and the quantum well active layer. A phase difference between a reflected ray of light reflected by the multilayer reflection film and an emitted ray of light from the quantum well active layer is a multiple of 2?. The semiconductor light emitting device stably obtains a specified peak wavelength even when there is slight variance in the distance between the upper surface of the multilayer reflection film and the lower surface of the quantum well active layer.

Abstract: A light emitting diode (LED) of a double hetero-junction type has a light-emitting layer of a GaAlInP material, a p-type cladding layer and an n-type cladding layer sandwiching the light-emitting layer therebetween, a p-side electrode formed on the p-type cladding layer side, and an n-side electrode formed on the n-type cladding layer side. The p-type cladding layer consists of a first p-type cladding layer positioned closer to the light-emitting layer and having a lower aluminum content and a lower impurity concentration, and a second p-type cladding layer positioned less closer to the light-emitting layer and having a higher aluminum content and a higher impurity concentration. The LED also has a current blocking layer below the p-side electrode for locally blocking electric current flowing from the p-side electrode to the n-side electrode.

Abstract: Is provided a resonant cavity type light emitting diode having excellent humidity durability and a light output unsaturated even several 10 mA., which is suitable for mass production. The semiconductor light emitting element has a resonator formed by one set of multi-layer reflecting films disposed at a constant distance on a GaAs substrate inclined at an angle of not less than 2 degrees in the direction [011] or [0-1-1] from the plane (100) and a light emitting layer disposed at a loop position of a standing wave in the resonator, wherein a multi-layer reflecting film disposed on the GaAs substrate side is composed of plural layers of AlxGa1-xAs (0?x?1) and a multi-layer reflecting film disposed on the opposite side of the GaAs substrate is composed of plural layers of AlyGazIn1-y-zP (0?y?1, 0?z?1), thereby achieving an improved humidity durability and an increased reflection factor by increasing the number of the reflection layers.

Abstract: An n-type AlAs/n-type Al0.5Ga0.5As DBR layer and a p-type (Al0.2Ga0.8)0.5In0.5P/p-type Al0.5In0.5P DBR layer are formed on an n-type GaAs substrate at specified intervals so that a reflection spectrum is centered at 650 nm and the resonance wavelength becomes 650 nm. A quantum well active layer (light-emitting layer) is formed so that the light emission peak wavelength becomes 650 nm in the belly position of the standing wave generated in a resonator constructed of both the DBR layers. A grating pattern is formed on the surface of a p-type Al0.5Ga0.5As light diffusion layer that serves as a light-emitting surface surrounded by a p-type electrode. By thus roughening the light-emitting surface, light emitted from the light-emitting layer is diffused in various directions, reducing the radiation angle dependency of the emission light wavelength.

Abstract: Is provided a resonant cavity type light emitting diode having excellent humidity durability and a light output unsaturated even several 10 mA., which is suitable for mass production. The semiconductor light emitting element has a resonator formed by one set of multi-layer reflecting films disposed at a constant distance on a GaAs substrate inclined at an angle of not less than 2 degrees in the direction [011] or [0-1-1] from the plane (100) and a light emitting layer disposed at a loop position of a standing wave in the resonator, wherein a multi-layer reflecting film disposed on the GaAs substrate side is composed of plural layers of AlxGa1-xAs (0 ≦x≦1) and a multi-layer reflecting film disposed on the opposite side of the GaAs substrate is composed of plural layers of AlyGazIn1-y-zP (0≦y≦1, 0≦z≦1), thereby achieving an improved humidity durability and an increased reflection factor by increasing the number of the reflection layers.

Abstract: An n-type AlAs/n-type Al0.5Ga0.5As DBR layer and a p-type (Al0.2Ga0.8)0.5In0.5P/p-type Al0.5In0.5P DBR layer are formed on an n-type GaAs substrate at specified intervals so that a reflection spectrum is centered at 650 nm and the resonance wavelength becomes 650 nm. A quantum well active layer (light-emitting layer) is formed so that the light emission peak wavelength becomes 650 nm in the belly position of the standing wave generated in a resonator constructed of both the DBR layers. A grating pattern is formed on the surface of a p-type Al0.5Ga0.5As light diffusion layer that serves as a light-emitting surface surrounded by a p-type electrode. By thus roughening the light-emitting surface, light emitted from the light-emitting layer is diffused in various directions, reducing the radiation angle dependency of the emission light wavelength.

Abstract: In a semiconductor laser element, an active layer is sandwiched between first-conductivity type and second-conductivity type cladding layers, and a second-conductivity type contact layer is disposed above the second cladding layer with an intermediate bandgap layer interposed between the second cladding layer and the contact layer, the second-conductivity type contact layer having a bandgap different from a bandgap of the second-conductivity type cladding layer, the intermediate bandgap layer having an intermediate bandgap between the bandgaps of the second-conductivity type cladding layer and the second-conductivity type contact layer. The second-conductivity type contact layer has at least a first contact layer, an intermediate second contact layer and a third contact layer stacked in this order and the second contact layer has an impurity density lower than impurity densities of the first and third contact layers.

Abstract: A semiconductor laser device of a III-V group compound includes a substrate including a main surface having an inclination angle of less than 20° toward a [011] direction from a (100) plane and an inclined facet further inclined toward the [011] direction from the main surface, a light emitting stacked-layered portion including at least an active layer and a clad layer over the substrate, and a current-constricting layer including a IV group impurity. The current-constricting layer has a region of an n type conductivity above the main surface of the substrate, and a region of a p type conductivity above the inclined facet of the substrate.

Abstract: A light emitting diode (LED) of a double hetero-junction type has a light-emitting layer of a GaAlInP material, a p-type cladding layer and an n-type cladding layer sandwiching the light-emitting layer therebetween, a p-side electrode formed on the p-type cladding layer side, and an n-side electrode formed on the n-type cladding layer side. The p-type cladding layer consists of a first p-type cladding layer positioned closer to the light-emitting layer and having a lower aluminum content and a lower impurity concentration, and a second p-type cladding layer positioned less closer to the light-emitting layer and having a higher aluminum content and a higher impurity concentration. The LED also has a current blocking layer below the p-side electrode for locally blocking electric current flowing from the p-side electrode to the n-side electrode.

Abstract: A light emitting diode (LED) of a double hetero-junction type has a light-emitting layer of a GaAlInP material, a p-type cladding layer and an n-type cladding layer sandwiching the light-emitting layer therebetween, a p-side electrode formed on the p-type cladding layer side, and an n-side electrode formed on the n-type cladding layer side. The p-type cladding layer consists of a first p-type cladding layer positioned closer to the light-emitting layer and having a lower aluminum content and a lower impurity concentration, and a second p-type cladding layer positioned less closer to the light-emitting layer and having a higher aluminum content and a higher impurity concentration. The LED also has a current blocking layer below the p-side electrode for locally blocking electric current flowing from the p-side electrode to the n-side electrode.

Abstract: In this semiconductor laser device, an InGaP etching block layer 11 as an etching selection layer having etching selectivity for an n-type AlInP current block layer 10, which is a non-optical-absorption layer, is formed on the n-type current block layer 10. Since this etching block layer 11 prevents the current block layer 10 on both sides of a ridge 20 from being etched during manufacture, a contact layer 12 can be prevented from entering gaps between the sides of this ridge 20 and the current block layer 10. Therefore, light oscillating in an active layer 4 is taken out from a device end surface without being absorbed in the contact layer 12. 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.

Abstract: The present invention relates to a semiconductor light-emitting device used for optical transmission (particularly for IEEE 1394) and displays and the like. More specifically, an object of the present invention is to provide a semiconductor light-emitting device capable of emitting the light with a high efficiency by extending a distance from an active layer to a boundary having poor crystal quality due to Group V elements As and P exchange to suppress deterioration in crystal quality of the active layer.

Abstract: A semiconductor light emitting device has in sequence on a semiconductor substrate, a multilayer reflection film, a semiconductor layer, and a quantum well active layer. A distance between an upper surface of the multilayer reflection film and a lower surface of the quantum well active layer is 2&lgr;/n or less, where &lgr; is a light emission wavelength and n is an average refractive index of the semiconductor layer disposed in between the multilayer reflection film and the quantum well active layer. A phase difference between a reflected ray of light reflected by the multilayer reflection film and an emitted ray of light from the quantum well active layer is a multiple of 2&pgr;. In an emission spectrum of the semiconductor light emitting device, two troughs caused by interference between the emitted ray of light and the reflected ray of light appear in the both sides of a main peak.

Abstract: A semiconductor light emitting device has in sequence on a semiconductor substrate, a multilayer reflection film, a semiconductor layer, and a quantum well active layer. A distance between an upper surface of the multilayer reflection film and a lower surface of the quantum well active layer is 2&lgr;/n or less, where &lgr; is a light emission wavelength and n is an average refractive index of the semiconductor layer disposed in between the multilayer reflection film and the quantum well active layer. A phase difference between a reflected ray of light reflected by the multilayer reflection film and an emitted ray of light from the quantum well active layer is a multiple of 2&pgr;. In an emission spectrum of the semiconductor light emitting device, two troughs caused by interference between the emitted ray of light and the reflected ray of light appear in the both sides of a main peak.

Abstract: In a semiconductor laser element, an active layer is sandwiched between first-conductivity type and second-conductivity type cladding layers, and a second-conductivity type contact layer is disposed above the second cladding layer with an intermediate bandgap layer interposed between the second cladding layer and the contact layer, the second-conductivity type contact layer having a bandgap different from a bandgap of the second-conductivity type cladding layer, the intermediate bandgap layer having an intermediate bandgap between the bandgaps of the second-conductivity type cladding layer and the second-conductivity type contact layer. The second-conductivity type contact layer has at least a first contact layer, an intermediate second contact layer and a third contact layer stacked in this order and the second contact layer has an impurity density lower than impurity densities of the first and third contact layers.