Abstract: A semiconductor device includes a semiconductor layer formed of a III-V group semiconductor crystal containing As as a primary component of a V group. A V group element other than As has been introduced at a concentration of 0.02 to 5% into a V group site of the III-V group semiconductor crystal in the semiconductor layer.

Abstract: A semiconductor device includes a semiconductor layer formed of a III-V group semiconductor crystal containing As as a primary component of a V group. A V group element other than As has been introduced at a concentration of 0.02 to 5% into a V group site of the III-V group semiconductor crystal in the semiconductor layer.

Abstract: A semiconductor laser device includes an active layer including a well layer and a barrier layer formed of a III-V group semiconductor crystal containing As as a primary component of a V group. A V group element other than As has been introduced at a concentration of 0.02 to 5% into a V group site of the III-V group semiconductor crystal in at least one of the well layer and the barrier layer, and a III group site of the III-V group semiconductor crystal in at least one of the well layer and the barrier layer contains Al.

Abstract: A semiconductor device of the invention is formed so that n-type InP current blocking layers enter the inside of p-type InP cladding layers, i.e., the n-type current blocking layers ride over the upper part of the p-type InP cladding layers, so that a distance between the n-type InP current block layers composing a current blocking region is narrower than a width of the p-type cladding layers contacting with the n-type InP current blocking layers. Thereby, the semiconductor device whose leak current in the current blocking region may be reduced which permits high-output and high-temperature operations may be readily fabricated.

Abstract: An interfacial reaction suppressing layer 12 formed between an oxide layer including a ZnO single crystal substrate 11 and a nitride layer including an InGaN semiconductor layer 13 restrains the interfacial reaction between the oxide layer and the nitride layer and formation of a reaction layer (Al2ZnO4) at the interface, which makes it possible to grow and thermally treat the InGaN semiconductor layer 13 at a high temperature. Thus, a crystal quality of the InGaN semiconductor layer 13 is improved.

Abstract: A semiconductor light emitting element of the present invention comprises: a zinc oxide (ZnO) single crystal substrate 12 with a substrate surface of a plane orientation insusceptible to a piezo electric field; a Lattice-matched layer 13 formed on the substrate surface to be lattice-matched with the ZnO single crystal substrate 12; an active layer 15 of indium gallium nitride (InxGa1-xN, 0<x<1); two of cladding layers 14 and 16 to be lattice-matched with the active layer 15 and/or the Lattice-matched layer 13.

Abstract: A semiconductor light emitting element comprising: a buffer layer that is grown by using a growth substrate including ZnO, the buffer layer being made by using an AlGaInN-based material including In and being configured so that the growth surface thereof has a nitrogen polar plane; and an active layer that is formed on the buffer layer, the active layer being made by using an AlGaInN-based material including In and being configured so that the growth surface thereof has a group-III polar plane.

Abstract: A semiconductor device of the invention is formed so that n-type InP current blocking layers enter the inside of p-type InP cladding layers, i.e., the n-type current blocking layers ride over the upper part of the p-type InP cladding layers, so that a distance between the n-type InP current block layers composing a current blocking region is narrower than a width of the p-type cladding layers contacting with the n-type InP current blocking layers. Thereby, the semiconductor device whose leak current in the current blocking region may be reduced which permits high-output and high-temperature operations may be readily fabricated.

Abstract: An interfacial reaction suppressing layer 12 formed between an oxide layer including a ZnO single crystal substrate 11 and a nitride layer including an InGaN semiconductor layer 13 restrains the interfacial reaction between the oxide layer and the nitride layer and formation of a reaction layer (Al2ZnO4) at the interface, which makes it possible to grow and thermally treat the InGaN semiconductor layer 13 at a high temperature. Thus, a crystal quality of the InGaN semiconductor layer 13 is improved.

Abstract: A semiconductor light emitting element of the present invention comprises: a zinc oxide (ZnO) single crystal substrate 12 with a substrate surface of a plane orientation insusceptible to a piezo electric field; a Lattice-matched layer 13 formed on the substrate surface to be lattice-matched with the ZnO single crystal substrate 12; an active layer 15 of indium gallium nitride (InxGa1-xN, 0<x<1); two of cladding layers 14 and 16 to be lattice-matched with the active layer 15 and/or the Lattice-matched layer 13.

Abstract: A laser gyro of the present invention includes laser light excitation means (a semiconductor laser device 100) that excites first and second laser lights propagating in the opposite directions to each other in a circular ring-shaped path (an optical path 40), coupling means (optical waveguides 41 and 42) for superimposing the first and the second laser lights, and a photodetector for observing an interference signal generated by the superimposed first and second laser lights.

Abstract: A DFB laser assembly including both a DFB laser device, with a buried heterostructure having a cavity length of 400 ?m, a differential resistance of 4?, an emission wavelength of 1550 nm, and a thermal resistance of 50K/watt or less, and a heat sink mounting the DFB laser device in a junction-down structure so that the DFB laser device has a wavelength/current coefficient at 5 picometers/milli-ampere or less.

Abstract: A laser gyro of the present invention includes laser light excitation means (a semiconductor laser device 100) that excites first and second laser lights propagating in the opposite directions to each other in a circular ring-shaped path (an optical path 40), coupling means (optical waveguides 41 and 42) for superimposing the first and the second laser lights, and a photodetector for observing an interference signal generated by the superimposed first and second laser lights.

Abstract: A GaAs based semiconductor laser having a combination of cladding layers including a ridge structure part, and a remaining part which overlays the active layers of the laser, and an etch stop layer sandwiched between the ridge structure part and the remaining part. The remaining part preferably overlies the entire surface of laser active layers and has a thickness “D” which satisfies 1.1×W>D?0.5×W wherein W is the width of a spot size having a strength of 1/e2 as measured at the laser front facet in a direction perpendicular to the active layers, wherein “e” is the base of the natural logarithm. The semiconductor laser solves the kink phenomenon to obtain an excellent linear relationship between the optical output power and the injected current.

Abstract: A method for manufacturing a semiconductor optical waveguide comprises the steps of forming a core layer having an Al content which monotonically increases from the central part thereof to the film surface, and selectively oxidizing the core layer to obtain a peripheral, oxidized region and a central, non-oxidized region acting as a waveguide. The waveguide is tapered to have a circular mode field at the distal end thereof for efficiently coupling with an optical fiber.

Abstract: An EA-DFB module including a DFB laser diode and an EA modulator formed on an InP first-conductivity-type substrate has a mesa stripe, a current blocking structure formed on both side surfaces of the mesa strip and a second InP cladding layer formed on top of the mesa stripe and the current blocking structure. The current blocking structure includes a Fe-doped semi-insulating film, a first conductivity-type buried layer and a carrier-depleted layer. The carrier-depleted layer reduces the parasitic capacitance at the boundary between the first-conductivity-type buried layer and the second InP cladding layer.

Abstract: Disclosed is a distributed feedback semiconductor laser device having a resonator for oscillating a laser beam and a laser module which is provided with the semiconductor laser device. The semiconductor laser device comprises a diffraction grating, formed inside the resonator, for periodically changing only an extinction coefficient k or both a real refractive index n and the extinction coefficient k in a complex refractive index N expressed by N=n−ik where i is an imaginary unit. The resonator has a first facet having a first reflectance and a second facet opposite to the first facet and having a second reflectance. The first reflectance is smaller than the second reflectance and equal to or larger than 10%, preferably equal to or smaller than 20%.

Abstract: A semiconductor laser device according to the present invention comprises a laminated structure of a semiconductor material including an active layer formed of a quantum well structure, a low-reflection film formed on one end face of the structure, and a high-reflection film formed on the other end face of the structure. The cavity length (L) of the device is 1,200 &mgr;m or more. This laser device, which enjoys high kink currents and a satisfactorily linear current-optical output characteristic, is a useful pumping light source for optical fiber amplifier.

Abstract: A semiconductor laser includes a resonant cavity with a cavity length, an active layer structure provided within the resonant cavity and configured to radiate light in an optical gain distribution having a peak wavelength, an embedding layer provided within the resonant cavity and having a refractive index, and a diffraction grating embedded within the embedding layer and having a bandgap wavelength and a refractive index, the diffraction grating configured to select an emission wavelength of the resonant cavity independently of the peak wavelength in the optical gain distribution of the active layer structure. The embedding layer and diffraction grating are configured to provide operational characteristics satisfying the relationship 0<&lgr;e−&lgr;g≦100 nm, where &lgr;e is the emission wavelength of the resonant cavity &lgr;g is the bandgap wavelength of the diffraction grating.

Abstract: A GaAs based semiconductor laser having a combination of cladding layers including a ridge structure part, and a remaining part which overlays the active layers of the laser, and an etch stop layer sandwiched between the ridge structure part and the remaining part. The remaining part preferably overlies the entire surface of laser active layers and has a thickness “D” which satisfies 1.1×W>D≧0.5×W wherein W is the width of a spot size having a strength of 1/e2 as measured at the laser front facet in a direction perpendicular to the active layers, wherein “e” is the base of the natural logarithm. The semiconductor laser solves the kink phenomenon to obtain an excellent linear relationship between the optical output power and the injected current.