Abstract: Provided is a semiconductor laser chip improved more in heat dissipation performance. This semiconductor laser chip includes a substrate, which has a front surface and a rear surface, nitride semiconductor layers, which are formed on the front surface of the substrate, an optical waveguide (ridge portion), which is formed in the nitride semiconductor layers, an n-side electrode, which is formed on the rear surface of the substrate, and notched portions, which are formed in regions that include the substrate to run along the optical waveguide (ridge portion). The notched portions have notched surfaces on which a metal layer connected to the n-side electrode is formed.

Abstract: In a laser chip 1 using a nitride semiconductor having a hexagonal crystal structure, the ?c plane is used as a first resonator facet A, which is the side of the laser chip 1 through which light is emitted. On the first resonator facet A, that is, on the ?c plane, a facet protection film 14 is formed. This ensures firm joint between the first resonator facet A and the facet protection film 14 and alleviates deterioration of the first resonator facet A.

Abstract: In a GaN-based laser device having a GaN-based semiconductor stacked-layered structure including a light emitting layer, the semiconductor stacked-layered structure includes a ridge stripe structure causing a stripe-shaped waveguide, and has side surfaces opposite to each other to sandwich the stripe-shaped waveguide in its width direction therebetween. At least part of at least one of the side surfaces is processed to prevent the stripe-shaped waveguide from functioning as a Fabry-Perot resonator in the width direction.

Abstract: Provided is a nitride semiconductor laser device that is reduced in capacitance to have a better response. The nitride semiconductor laser device includes: an active layer; an upper cladding layer which is stacked above the active layer; a low dielectric constant insulating film which is stacked above the upper cladding layer; and a pad electrode which is stacked above the low dielectric constant insulating film.

Abstract: At each side of a ridge stripe 110, a trench is formed as a region carved relative to a wafer surface so that, at the time of cleaving, a surface irregularity that develops at a mirror facet near an active layer is prevented from reaching the ridge stripe 110.

Abstract: In a laser chip 1 using a nitride semiconductor having a hexagonal crystal structure, the ?c plane is used as a first resonator facet A, which is the side of the laser chip 1 through which light is emitted. On the first resonator facet A, that is, on the ?c plane, a facet protection film 14 is formed. This ensures firm joint between the first resonator facet A and the facet protection film 14 and alleviates deterioration of the first resonator facet A.

Abstract: A nitride semiconductor laser chip is provided that can not only improve its COD level but also prevent its I-L characteristic curve from rising steeply and that can reduce an operating voltage. The nitride semiconductor laser chip includes layers constituting a nitride semiconductor layer and formed on an n-type GaN substrate, mirror facets including a light emission mirror facet and a light reflection mirror facet, a p-side ohmic contact formed on an upper contact layer to reach the mirror facets and a p-side pad contact formed in a region only a distance L1 away from the light emission mirror facet. The thickness d of the p-side ohmic contact and the distance L1 from the p-side ohmic contact to the light emission mirror facet are adjusted such that the amount of current injected into the light emission mirror facet is 20% or more but 70% or less of the amount of current injected into an area directly below the p-side pad contact.

Abstract: In a nitride semiconductor laser device so structured as to suppress development of a step on nitride semiconductor layers, the substrate has the (11-20) plane as the principal plane, the resonator end surface is perpendicular to the principal plane, and, in the cleavage surface forming the resonator end surface, at least by one side of a stripe-shaped waveguide, an etched-in portion is formed as an etched-in region open toward the surface of the nitride semiconductor layers.

Abstract: In a nitride semiconductor laser chip so structured as to suppress development of a step on nitride semiconductor layers, the substrate has the (1-100) plane as the principal plane, the resonator facet is perpendicular to the principal plane, and, in the cleavage surface forming the resonator facet, at least by one side of a stripe-shaped waveguide, an etched-in portion is formed as an etched-in region open toward the surface of the nitride semiconductor layers.

Abstract: A worn type electronic device comprises: a light emitting element for emitting a light having a specified wave length and a light guide means for guiding the light emitted from the light emitting element in a specified direction; the light emitting element disposed in a body of the worn type electronic device, wherein a light emission of the light emitting element is controlled based on the control of the worn type electronic device; and the light guide means including at least one of a body side light guide means disposed in the body of the worn type electronic device and a band side light guide means disposed in a band, wherein the light emitted from the light emitting element is emitted from the surface of the body of the worn type electronic device via the body side light guide means; or wherein the light emitted from the light emitting element is emitted from the surface of the band via the band side light guide means.

Abstract: At each side of a ridge stripe 110, a trench is formed as a region carved relative to a wafer surface so that, at the time of cleaving, a surface irregularity that develops at a mirror facet near an active layer is prevented from reaching the ridge stripe 110.

Abstract: A nitride semiconductor light emitting device includes at least a substrate, an active layer formed of a nitride semiconductor containing mainly In and Ga, a p-electrode and an n-electrode. At least one of the p-electrode and n-electrode is electrically separated into at least two regions.

Abstract: According to an aspect of the present invention, a nitride semiconductor laser device includes a nitride semiconductor active layer, and a stripe-shaped waveguide for guiding light generated in the active layer. At least one pair of light-absorbing films are provided in at least local regions on the opposite sides of the stripe-shaped waveguide, to reach a distance within 0.3 ?m from the waveguide. According to another aspect of the present invention, a gan-based semiconductor laser device includes first conductivity type semiconductor layers, a semiconductor active layer and second conductivity type semiconductor layers stacked sequentially. The laser device further includes a ridge stripe provided to cause a refractive index difference for confinement of light in a lateral direction crossing a longitudinal direction of a cavity, and a current-introducing window portion provided on the ridge stripe.

Abstract: A multi-wavelength laser device includes at least two of a blue laser diode, a red laser diode, and an infrared laser diode, which are arranged in the same direction on the same base. One laser light emission point is arranged behind another in increasing order of wavelengths of the laser diodes.

Abstract: In a wafer having an LD structure 251 formed on a GaN-based substrate 250, cleavage guide grooves 252 are formed in its surface by scribing from above the LD structure 251 with a diamond needle. The cleavage guide grooves 252 are formed one along each of stripe-shaped waveguides 253 formed parallel to the <1-100> direction of the wafer, and are formed in the shape of broken lines in the <11-20> direction of the wafer.

Abstract: In connection with a nitride semiconductor laser device optimal for example for optical pickup and an optical information reproduction apparatus having superior condensation characteristics, the semiconductor laser device includes a substrate of nitride semiconductor, a lower clad layer of nitride semiconductor stacked thereon, an active layer stacked thereon, an upper clad layer of nitride semiconductor stacked thereon, and a contact layer of AlaInbGa1?a?bN stacked thereon having a lattice constant larger than the substrate of nitride semiconductor, and the device is cleaved and thus divided to have a surface serving as a resonator mirror.

Abstract: In a GaN-based laser device (100) having a GaN-based semiconductor stacked-layered structure including a light emitting layer (106), the semiconductor stacked-layered structure includes a ridge stripe structure (111) causing a stripe-shaped waveguide, and has side surfaces (117, 118) opposite to each other to sandwich the stripe-shaped waveguide in its width direction therebetween. At least part of at least one of the side surfaces (117, 118) is processed to prevent the stripe-shaped waveguide from functioning as a Fabry-Perot resonator in the width direction.

Abstract: According to an aspect of the present invention, a nitride semiconductor laser device includes a nitride semiconductor active layer (106), and a stripe-shaped waveguide for guiding light generated in the active layer. At least one pair of light-absorbing films (112) are provided in at least local regions on the opposite sides of the stripe-shaped waveguide, to reach a distance within 0.3 &mgr;m from the waveguide. According to another aspect of the present invention, a GaN-based semiconductor laser device includes first conductivity type semiconductor layers (103-105), a semiconductor active layer (106) and second conductivity type semiconductor layers (107-110) stacked sequentially. The laser device further includes a ridge stripe (111) provided to cause a refractive index difference for confinement of light in a lateral direction crossing a longitudinal direction of a cavity, and a current-introducing window portion (114) provided on the ridge stripe.

Abstract: A multi-wavelength laser device includes at least two of a blue laser diode, a red laser diode, and an infrared laser diode, which are arranged in the same direction on the same base. One laser light emission point is arranged behind another in increasing order of wavelengths of the laser diodes.

Abstract: In a wafer having an LD structure 251 formed on a GaN-based substrate 250, cleavage guide grooves 252 are formed in its surface by scribing from above the LD structure 251 with a diamond needle. The cleavage guide grooves 252 are formed one along each of stripe-shaped waveguides 253 formed parallel to the <1-100> direction of the wafer, and are formed in the shape of broken lines in the <11-20> direction of the wafer.