Abstract: One facet and the other facet of a nitride based semiconductor laser device are respectively composed of a cleavage plane of (0001) and a cleavage plane of (000 1). Thus, the one facet and the other facet are respectively a Ga polar plane and an N polar plane. A portion of the one facet and a portion of the other facet, which are positioned in an optical waveguide, constitute a pair of cavity facets. A first protective film including oxygen as a constituent element is formed on the one facet. A second protective film including nitrogen as a constituent element is formed on the other facet.

Abstract: A nitride-based semiconductor laser device includes a front facet located on a forward end of an optical waveguide and formed by a substantially (000-1) plane of a nitride-based semiconductor layer and a rear facet located on a rear end of the optical waveguide and formed by a substantially (0001) plane of the nitride-based semiconductor layer, wherein an intensity of a laser beam emitted from the front facet is rendered larger than an intensity of a laser beam emitted from the rear facet.

Abstract: A nitride-based semiconductor light-emitting device capable of improving luminous efficiency by reducing light absorption loss in a contact layer is provided. This nitride-based semiconductor light-emitting device comprises a first conductivity type first nitride-based semiconductor layer formed on a substrate, an active layer, formed on the first nitride-based semiconductor layer, consisting of a nitride-based semiconductor layer, a second conductivity type second nitride-based semiconductor layer formed on the active layer, an undoped contact layer formed on the second nitride-based semiconductor layer and an electrode formed on the undoped contact layer.

Abstract: A monolithic red/infrared semiconductor laser device is joined to a blue-violet semiconductor laser device. The distance between a blue-violet emission point in the blue-violet semiconductor laser device and an infrared emission point in an infrared semiconductor laser device is significantly shorter than the distance between a red emission point in a red semiconductor laser device and the infrared emission point. A blue-violet laser beam, a red laser beam, and an infrared laser beam respectively emitted from the blue-violet emission point, the red emission point, and the infrared emission point are introduced into a photodetector after being incident on an optical disk by an optical system comprising a polarizing beam splitter, a collimator lens, a beam expander, a ?/4 plate, an objective lens, a cylindrical lens, and an optical axis correction element.

Abstract: A semiconductor laser device includes a substrate made of a nitride-based semiconductor and a waveguide formed on a principal surface of the substrate, wherein the substrate includes a dislocation concentrated region arranged so as to obliquely extend with respect to the principal surface of the substrate, and the waveguide is so formed as to be located above the dislocation concentrated region and also located on a region except a portion where the dislocation concentrated region is present in the principal surface of the substrate.

Abstract: A nitride-based semiconductor laser device capable of elongating the life thereof is obtained. This nitride-based semiconductor laser device comprises a first cladding layer consisting of a first conductivity type nitride-based semiconductor, an emission layer, formed on the first cladding layer, consisting of a nitride-based semiconductor and a second cladding layer, formed on the emission layer, consisting of a second conductivity type nitride-based semiconductor, while the emission layer includes an active layer emitting light, a light guiding layer for confining light and a carrier blocking layer, arranged between the active layer and the light guiding layer, having a larger band gap than the light guiding layer.

Abstract: A method of fabricating a nitride-based semiconductor device capable of reducing contact resistance between a nitrogen face of a nitride-based semiconductor substrate or the like and an electrode is provided. This method of fabricating a nitride-based semiconductor device comprises steps of etching the back surface of a first semiconductor layer consisting of either an n-type nitride-based semiconductor layer or a nitride-based semiconductor substrate having a wurtzite structure and thereafter forming an n-side electrode on the etched back surface of the first semiconductor layer.

Abstract: In this semiconductor laser device, a semiconductor laser element is so fixed to a base that a distance between a convex side of a warp thereof and the base varies with the warp of the semiconductor laser element at least along a first direction corresponding to an extensional direction of a cavity or a second direction, while a wire bonding portion is provided around a portion of an electrode layer corresponding to the vicinity of a region where the distance between the convex side of the warp of the semiconductor laser element in at least either the first direction or the second direction of the semiconductor laser element and the base is substantially the smallest.

Abstract: In a semiconductor laser device, a semiconductor laser element is so fixed to a base that a distance between a convex side of a warp of the semiconductor laser element and the base varies with the warp of the semiconductor laser element along a first direction corresponding to an extensional direction of a cavity while a wire bonding portion is provided around a portion of an electrode layer corresponding to the vicinity of a region where the distance is the largest.

Abstract: A nitride-based semiconductor laser device capable of elongating the life thereof is obtained. This nitride-based semiconductor laser device comprises a first cladding layer consisting of a first conductivity type nitride-based semiconductor, an emission layer, formed on the first cladding layer, consisting of a nitride-based semiconductor and a second cladding layer, formed on the emission layer, consisting of a second conductivity type nitride-based semiconductor, while the emission layer includes an active layer emitting light, a light guiding layer for confining light and a carrier blocking layer, arranged between the active layer and the light guiding layer, having a larger band gap than the light guiding layer.

Abstract: Provided is a manufacturing method of a nitride semiconductor device having a nitride semiconductor substrate (e.g. GaN substrate) in which dislocation concentrated regions align in stripe formation, the dislocation concentrated regions extending from a front surface to a back surface of the substrate, the manufacturing method being for stacking each of a plurality of nitride semiconductor layers on the front surface of the substrate in a constant film thickness. Grooves are formed on the nitride semiconductor substrate in the immediate areas of dislocation concentrated regions. Each of the nitride semiconductor layers is formed as a crystal growth layer on the main surface of the nitride semiconductor substrate to which the grooves have been formed.

Abstract: A nitride-based semiconductor light-emitting device capable of stabilizing transverse light confinement is obtained. This nitride-based semiconductor light-emitting device comprises an emission layer, a cladding layer, formed on the emission layer, including a first nitride-based semiconductor layer and having a current path portion and a current blocking layer, formed to cover the side surfaces of the current path portion, including a second nitride-based semiconductor layer, while the current blocking layer is formed in the vicinity of the current path portion and a region having no current blocking layer is included in a region not in the vicinity of the current path portion. Thus, the width of the current blocking layer is reduced, whereby strain applied to the current blocking layer is relaxed. Consequently, the thickness of the current blocking layer can be increased, thereby stabilizing transverse light confinement.

Abstract: A semiconductor laser diode apparatus capable of suppressing variation in an emission position and an emission direction of a laser beam emitted from a semiconductor laser diode element is obtained. This semiconductor laser diode apparatus includes a semiconductor laser diode element having warping along either a first direction in which a cavity extends or a second direction intersecting with the first direction and a base on which a convex side of the warping of the semiconductor laser diode element is fixed, wherein a distance between a first end of the semiconductor laser diode element in a direction of larger warping among the first and second directions and the base is smaller than a distance between a second end of the semiconductor laser diode element in the direction of the large warping among the first and second directions and the base.

Abstract: A method of fabricating a nitride-based semiconductor device capable of reducing contact resistance between a nitrogen face of a nitride-based semiconductor substrate or the like and an electrode is provided. This method of fabricating a nitride-based semiconductor device comprises steps of etching the back surface of a first semiconductor layer consisting of either an n-type nitride-based semiconductor layer or a nitride-based semiconductor substrate having a wurtzite structure and thereafter forming an n-side electrode on the etched back surface of the first semiconductor layer.

Abstract: Provided is a manufacturing method of a nitride semiconductor device having a nitride semiconductor substrate (e.g. GaN substrate) in which dislocation concentrated regions align in stripe formation, the dislocation concentrated regions extending from a front surface to a back surface of the substrate, the manufacturing method being for stacking each of a plurality of nitride semiconductor layers on the front surface of the substrate in a constant film thickness. Grooves are formed on the nitride semiconductor substrate in the immediate areas of dislocation concentrated regions. Each of the nitride semiconductor layers is formed as a crystal growth layer on the main surface of the nitride semiconductor substrate to which the grooves have been formed.

Abstract: A nitride-based semiconductor device includes a substrate constituted by nitride-based semiconductor, a nitride-based semiconductor layer formed on the substrate and constituted by nitride-based semiconductor, formed with a light waveguide extending in a first direction, and first step portions formed at least on regions other than the vicinity of facets of the light waveguide from a surface opposite to a side where the nitride-based semiconductor layer of the substrate is formed along the first direction in which the light waveguide extends.

Abstract: A blue-violet emission point, an infrared emission point, and a red emission point in a semiconductor laser apparatus are arranged so as to be arranged in this order on a substantially straight line along a first direction. A blue-violet laser beam emitted from the blue-violet emission point and a red laser beam emitted from the red emission point are incident on an optical disk by an optical system comprising a polarizing beam splitter, a collimator lens, a beam expander, a ?/4 plate, an objective lens, a cylindrical lens, and an optical disk, is returned from the optical disk, and is introduced into an photodetector. The infrared laser beam emitted from the infrared emission point is incident on the optical disk by the optical system, is returned from the optical disk, and is introduced into the photodetector.

Abstract: A semiconductor device capable of stabilizing operations thereof is provided. This semiconductor device comprises a substrate provided with a region having concentrated dislocations at least on part of the back surface thereof, a semiconductor element layer formed on the front surface of the substrate, an insulator film formed on the region of the back surface of the substrate having concentrated dislocations and a back electrode formed to be in contact with a region of the back surface of the substrate other than the region having concentrated dislocations.

Abstract: A fluorescent substance containing resin fills a container in a light emitting apparatus so as to cover a light emitting device and a spacer. In a region where the power of light emitted from the light emitting device is high, the volume of the first fluorescent element containing a blue light emitting fluorescent material is large. In a region where the power of the emitted light is low, the volume of a second fluorescent element containing a green light emitting fluorescent material and a red light emitting fluorescent material is large.

Abstract: A semiconductor device capable of stabilizing operations thereof is provided. This semiconductor device comprises a substrate provided with a region having concentrated dislocations at least on part of the back surface thereof, a semiconductor element layer formed on the front surface of the substrate, an insulator film formed on the region of the back surface of the substrate having concentrated dislocations and a back electrode formed to be in contact with a region of the back surface of the substrate other than the region having concentrated dislocations.