Abstract: A method of making an ohmic contact from a multi-metal-layer includes increasing a temperature in an annealing furnace containing the multi-metal-layer to a temperature within a first temperature range, from a temperature lower by 100° C. than a minimum melting point, which is the lowest melting point among melting points of the respective layers of the multi-metal-layer, to the minimum melting point, maintaining the temperature within the first temperature range, increasing the temperature in the furnace to a temperature to within a second temperature range, lower than a maximum melting point, which is the highest melting point of the respective layers of the multi-metal-layer, to higher than the minimum melting point among melting points of the respective layers of the multi-metal-layer, at a temperature increasing speed of 5° C./sec to 20° C./sec, and maintaining the temperature within the second temperature range.

Abstract: A method of making an ohmic contact from a multi-metal-layer includes increasing a temperature in an annealing furnace containing the multi-metal-layer to a temperature within a first temperature range, from a temperature lower by 100° C. than a minimum melting point, which is the lowest melting point among melting points of the respective layers of the multi-metal-layer, to the minimum melting point, maintaining the temperature within the first temperature range, increasing the temperature in the furnace to a temperature to within a second temperature range, lower than a maximum melting point, which is the highest melting point of the respective layers of the multi-metal-layer, to higher than the minimum melting point among melting points of the respective layers of the multi-metal-layer, at a temperature increasing speed of 5° C./sec to 20° C./sec, and maintaining the temperature within the second temperature range.

Abstract: An optical semiconductor device comprises: a semiconductor light emitting element including semiconductor layers, including an active layer having a quantum well structure and epitaxially grown on a semiconductor substrate; and a submount on which the semiconductor light emitting element is mounted. Strain in the active layer after mounting the semiconductor light emitting element on the submount is larger than strain in the active layer after epitaxial growth of the active layer. The strain in the active layer during the epitaxial growth results in the surface of the semiconductor layers being a mirror surface. The strain in the active layer after the semiconductor light emitting element is mounted on the submount would not result in a mirror surface if present in the active layer at the epitaxial growth.

Abstract: A method for manufacturing a semiconductor optical device includes forming a BDR (Band Discontinuity Reduction) layer of a first conductivity type doped with an impurity, depositing a contact layer of the first conductivity type in contact with the BDR layer after forming the the BDR layer, the contact layer being doped with the same impurity as the BDR layer and used to form an electrode, and heat treating after forming the contact layer.

Abstract: A method for manufacturing a semiconductor optical device includes: forming a p-type cladding layer; forming a capping layer on the p-type cladding layer, the capping layer being selectively etchable relative to the p-type cladding layer; forming a through film on the capping layer; forming a window structure by ion implantation; removing the through film after the ion implantation; and selectively removing the capping layer using a chemical solution.

Abstract: A laser diode includes a first n-cladding layer disposed on and lattice-matched to an n-semiconductor substrate, wherein the first n-cladding layer is n-AlGaInP or n-GaInP; a second n-cladding layer of n-AlGaAs supported by the first n-cladding layer; and an inserted layer disposed between the first n-cladding layer and the second n-cladding layer, wherein the inserted layer includes the same elements as the first n-cladding layer, the inserted layer has the same composition ratios of Al and Ga (and P) as the first n-cladding layer, and the inserted layer contains a lower composition ratio of In than the first n-cladding layer.

Abstract: In a semiconductor laser, a n-type AlGaInP clad layer is formed on a n-type GaAs substrate and an active layer having an emission wavelength of 600 to 850 nm is formed on the n-type AlGaInP clad layer. A p-type AlGaInP clad layer is formed on the active layer and a p-type AlGaAs contact layer in which the Al composition is controlled so that the p-type AlGaAs contact layer has an optical bandgap larger than that of the active layer is formed on the p-type AlGaInP clad layer. A p-type GaAs cap layer is formed on the p-type AlGaAs contact layer.

Abstract: A laser diode includes a first n-cladding layer disposed on and lattice-matched to an n-semiconductor substrate, wherein the first n-cladding layer is n-AlGaInP or n-GaInP; a second n-cladding layer of n-AlGaAs supported by the first n-cladding layer; and an inserted layer disposed between the first n-cladding layer and the second n-cladding layer, wherein the inserted layer includes the same elements as the first n-cladding layer, the inserted layer has the same composition ratios of Al and Ga (and P) as the first n-cladding layer, and the inserted layer contains a lower composition ratio of In than the first n-cladding layer.

Abstract: A method for manufacturing a semiconductor optical device includes: forming a p-type cladding layer; forming a capping layer on the p-type cladding layer the capping layer being selectively etchable relative to the p-type cladding layer; forming a through film on the capping layer; forming a window structure by in implantation; removing the through film after the ion implantation; and selectively removing the capping layer using a chemical solution.

Abstract: A method for manufacturing a semiconductor optical device includes forming a BDR (Band Discontinuity Reduction) layer of a first conductivity type doped with an impurity, depositing a contact layer of the first conductivity type in contact with the BDR layer after forming the BDR layer, the contact layer being doped with the same impurity as the BDR layer and used to form an electrode, and heat treating after forming the contact layer.

Abstract: A laser diode includes a first n-cladding layer disposed on and lattice-matched to an n-semiconductor substrate, wherein the first n-cladding layer is n-AlGaInP or n-GaInP; a second n-cladding layer of n-AlGaAs supported by the first n-cladding layer; and an inserted layer disposed between the first n-cladding layer and the second n-cladding layer, wherein the inserted layer includes the same elements as the first n-cladding layer, the inserted layer has the same composition ratios of Al and Ga (and P) as the first n-cladding layer, and the inserted layer contains a lower composition ratio of In than the first n-cladding layer.

Abstract: The semiconductor laser device includes an active layer, a p-type cladding layer, and a p-type cap layer. The layers are sequentially stacked so that the semiconductor laser device is provided. The p-type cap layer includes both a p-type dopant and an n-type dopant. In another aspect, the p-type cap layer includes a first layer including a first p-type dopant and a second layer including a second p-type dopant having a diffusion coefficient smaller than that of the first p-type dopant. The first layer is far from the active layer, and the second layer is close to the active layer. In further aspect, the p-type cap layer includes carbon (C) as a p-type dopant. According to these configuration, the p-type dopant can be prevented from being diffused in the active layer and the p-type cladding layer.

Abstract: A laser diode includes a first n-cladding layer disposed on and lattice-matched to an n-semiconductor substrate, wherein the first n-cladding layer is n-AlGaInP or n-GaInP; a second n-cladding layer of n-AlGaAs supported by the first n-cladding layer; and an inserted layer disposed between the first n-cladding layer and the second n-cladding layer, wherein the inserted layer includes the same elements as the first n-cladding layer, the inserted layer has the same composition ratios of Al and Ga (and P) as the first n-cladding layer, and the inserted layer contains a lower composition ratio of In than the first n-cladding layer.

Abstract: An n-type first cladding layer, a first guide layer, a first enhancing layer, an active layer, a second enhancing layer, a second guide layer, and a p-type second cladding layer are sequentially stacked on an n-type GaAs substrate. The thickness of each of the first guide layer and the second guide layer is 100 nm or more. In such a semiconductor laser, the difference between the Eg (band gap energy) of the first guide layer and the Eg of the active layer (or the difference between the Eg of the second guide layer and the Eg of the active layer) is made 0.66 times or less of the difference between the Eg of the first cladding layer and the Eg of the active layer (or the difference between the Eg of the second cladding layer and the Eg of the active layer).

Abstract: A semiconductor optical element having a includes an n-type GaAs buffer layer, an n-type AlGaInP cladding layer, a first InGaAsP (including zero As content)guide layer without added dopant impurities, an InGaAsP (including zero In content) active layer, a second InGaAsP (including zero As content)guide layer without added dopant impurities, a p-type AlGaInP cladding layer, a p-type band discontinuity reduction layer, and a p-type GaAs contact layer sequentially laminated on an n-type GaAs substrate C or Mg is the dopant impurity in the p-type GaAs contact layer, the p-type band discontinuity reduction layer, and the p-type AlGaInP cladding layer.

Abstract: An n-type first cladding layer, a first guide layer, a first enhancing layer, an active layer, a second enhancing layer, a second guide layer, and a p-type second cladding layer are sequentially stacked on an n-type GaAs substrate. The thickness of each of the first guide layer and the second guide layer is 100 nm or more. In such a semiconductor laser, the difference between the Eg (and gap energy) of the first guide layer and the Eg of the active layer (or the difference between the Eg of the second guide layer and the Eg of the active layer) is made 0.66 times or less of the difference between the Eg of the first cladding layer and the Eg of the active layer (or the difference between the Eg of the second cladding layer and the Eg of the active layer).

Abstract: A method of manufacturing a semiconductor film including a setting a substrate on a satellite; and a forming an alloy semiconductor thin film containing at least two different group V elements or group IV elements on the substrate by metal organic chemical vapor deposition while supplying thermal energy to the substrate through the satellite. The satellite comprises a flat satellite body on which the substrate is placed and a perimeter fixing section which fixes the perimeter of the substrate. The perimeter fixing section contacts only part of the perimeter of the substrate, instead of the entire perimeter of the substrate.

Abstract: A ridge waveguide semiconductor laser includes an active layer, semiconductor layers on the active layer and having a ridge-shaped waveguide, an insulating film on the semiconductor layer, a first electrode layer in contact with the semiconductor layer through an opening in the insulating film, and a second electrode layer on the first electrode layer having a stripe shape and extending along the waveguide. A distance from an end face of a resonator of the laser to an edge of the second electrode layer does not exceed 20 ?m.

Abstract: A semiconductor laser device includes: on an n-GaAs substrate, an n-type cladding layer of n-(Al0.3Ga0.7)0.5In1.5P, an n-side guide layer of i-In0.49Ga0.51P lattice-matched to GaAs, an active layer having a larger refractive index than the n-side guide layer, and including an In0.07Ga0.93As quantum well layer, a p-side guide layer of i-In0.49Ga0.51P, and a p-type cladding layer of p-(Al0.3Ga0.7)0.5In0.5P. Therefore, the anti-COD level increased, and internal loss minimized.

Abstract: A semiconductor optical element having a includes an n-type GaAs buffer layer, an n-type AlGaInP cladding layer, a first InGaAsP (including zero As content) guide layer without added dopant impurities, an InGaAsP (including zero In content) active layer, a second InGaAsP (including zero As content) guide layer without added dopant impurities, a p-type AlGaInP cladding layer, a p-type band discontinuity reduction layer, and a p-type GaAs contact layer sequentially laminated on an n-type GaAs substrate C or Mg is the dopant impurity in the p-type-GaAs contact layer, the p-type band discontinuity reduction layer, and the p-type AlGaInP cladding layer.