Abstract: A two wavelength laser module is made up of a semiconductor laser assembly that includes a first semiconductor laser for emitting a first light beam of a first polarization direction and a second semiconductor laser for emitting a second light beam of a second polarization direction. The second light beam is emitted approximately in the same direction as that of the first light beam and has a shorter wavelength than that of the first light beam. The first and second semiconductor lasers are disposed on a substrate. The module includes a polarization diffraction element for causing a divergence angle of the first light beam to differ from that of the second light beam.

Abstract: A semiconductor laser device comprises: a first light-emitting element having a first laser part, an insulating layer, and an ohmic electrode layer; and a second light-emitting element having a second laser part, an insulating layer, and an ohmic electrode layer. The first laser part has a ridge waveguide, and is formed by stacking thin films of group-III nitride compound semiconductors (for example, GaN-based semiconductors). The second laser part has a ridge waveguide, and is formed by stacking thin films of group III-V compound semiconductors (such as GaAs). The first laser part and the second laser part are integrally bonded to each other by the interposition of an adhesive metal layer which is formed between the ohmic electrode layers. This provides the semiconductor laser device with a small distance between the light-emitting spots of the laser parts.

Abstract: A nitride compound semiconductor laser, of which driving voltage is low and transverse mode of light is stable, having a plurality of crystal layers made of a group III nitride compound semiconductor expressed by the formula (AlGa1-x)1-yInyN (0≦x≦1, 0≦y≦1). The layers include an active layer-side guide layer which is adjacent to an active layer in the crystal layers of the group III nitride compound semiconductor and made of Alx′Ga1-x′-y′Iny′N (0≦x′≦1, 0≦y′≦1), a current constricting AlN layer deposited on said guide layer and having a stripe-shape aperture, an electrode-side guide layer made of Alx″Ga1-x″-y″Iny″N (0≦x″≦1, 0≦y″≦1) and deposited filling the aperture of the current constricting layer, and a clad layer made of AluGa1-u-vInvN (0≦u≦1, 0≦v≦1) and deposited on the electrode-side guide layer.

Abstract: An improved semiconductor laser device is provided which has a small distance between laser light emitting spots. Such laser device comprises i) a first light emitting element including a laser oscillation section provided with a ridge waveguide and formed by forming a group-III nitride semiconductor film on a substrate, an insulating layer and an ohmic electrode layer, ii) a second light emitting element including a laser oscillation section provided with a waveguide and formed by forming III-V compound semiconductor film, an insulating layer and an ohmic electrode layer. By virtue of the adhesive metal layer interposed between the two ohmic electrode layers, the two laser oscillation sections are combined together, thereby forming the improved semiconductor laser device which has a small distance between laser light emitting spots of the two laser oscillation sections.

Abstract: A group-III nitride semiconductor laser device with excellent optical characteristics and its manufacturing method are provided. The method does not include steps that require high assembly precision. The group-III nitride semiconductor laser device comprises a substrate which has a cut-out portion. A laser facet of a multi-layer body is located near the cut-out portion of the substrate.

Abstract: A group-III nitride semiconductor laser device with excellent optical characteristics and its manufacturing method are provided. The method does not include steps that require high assembly precision. The group-III nitride semiconductor laser device comprises a substrate which has a cut-out portion. A laser facet of a multi-layer body is located near the cut-out portion of the substrate.

Abstract: A nitride compound semiconductor laser, of which driving voltage is low and transverse mode of light is stable, having a plurality of crystal layers made of a group III nitride compound semiconductor expressed by the formula (AlxGa1-x)1-yInyN (0≦x≦1, 0≦y≦1). The layers include an active layer-side guide layer which is adjacent to an active layer in the crystal layers of the group III nitride compound semiconductor and made of Alx′Ga1-x′-y′Iny′N (0≦x′≦1, 0≦y′≦1), a current constricting AlN layer deposited on said guide layer and having a stripe-shape aperture, an electrode-side guide layer made of Alx″Ga1-x″-y″Iny″N (0≦x″≦1, 0≦y″≦1) and deposited filling the aperture of the current constricting layer, and a clad layer made of AluGa1-u-vInvN (0≦u≦1, 0≦v≦1) and deposited on the electrode-side guide layer.

Abstract: A group-III nitride semiconductor laser device with excellent optical characteristics and its manufacturing method are provided. The method does not include steps that require high assembly precision. The group-III nitride semiconductor laser device comprises a substrate which has a cut-out portion. A laser facet of a multi-layer body is located near the cut-out portion of the substrate.

Abstract: A group III nitride semiconductor device producing method is constructed by: a step of forming a first crystal layer made of a group III nitride semiconductor (AlxGa1−x)1−y.InyN (0≦×≦1, 0≦y≦1) doped with a group II impurity element; a step of a second crystal layer made of a group III nitride semiconductor AlzGa1−zN (0.7≦z≦1) onto the first crystal layer; and a step of removing at least a part of the second crystal layer by etching after the formation of the first and second crystal layers.

Abstract: The disclosure is a method for fabricating a nitride semiconductor laser device of group-III nitride semiconductor having a substrate. The method includes a step of forming a crystal layer made of a group-III nitride semiconductor (AlxGa1-x)1-yInyN (0≦x≦1, 0≦y≦1) having an added group II element over the substrate; a step of heating the crystal layer up to a predetermined temperature in a thermal treatment atmosphere and maintaining the predetermined temperature for a first time period; and a step of introducing a hydrocarbon gas into the thermal treatment atmosphere for at least a partial time period within the first time period. The method further includes a step of irradiating an electromagnetic wave or photons to the crystal layer in the at least a partial time period, wherein the electromagnetic wave or photons have an energy greater than an energy forbidden band width of the group III nitride semiconductor in the crystal layer.

Abstract: A GaN type semiconductor layer in which a group 2 impurity element is added is formed. The GaN type semiconductor layer is heated at a predetermined temperature, while irradiating the semiconductor layer with an electromagnetic wave having an energy larger than the band gap energy of the GaN type semiconductor layer.

Abstract: A process for producing a semiconductor emitting device of group III nitride semiconductor having a crystal layer (Al.sub.x Ga.sub.1-x).sub.1-y In.sub.y N (0.ltoreq.x.ltoreq.1, 0.ltoreq.y.ltoreq.1) includes; a step of forming at least one pn-junction or pin-junction and a crystal layer (Al.sub.x Ga.sub.1-x).sub.1-y In.sub.y N (0.ltoreq.x.ltoreq.1, 0.ltoreq.y.ltoreq.1) to which a group II element is added; and a step of forming electrodes on the crystal layer. The process further includes an electric-field-assisted annealing treatment in which the pn-junction or pin-junction is heated to the predetermined temperature range while forming and maintaining an electric field across the pn-junction or pin-junction for at least partial time period of the predetermined temperature range via the electrodes.