The present invention relates to a vertical cavity surface emitting laser (VCSEL) and a manufacturing method thereof, and more specifically, to a high-efficiency oxidized vertical cavity surface emitting laser for emitting laser light having a peak wavelength of 860 nm, and a manufacturing method thereof. The vertical cavity surface emitting laser according to the present invention includes a current diffusion layer having a high doping region at least in a portion between an upper electrode and a lower distributed Bragg reflector.

Apparatus comprise a semiconductor waveguide extending along a longitudinal axis and including a first waveguide section and a second waveguide section, wherein a lateral refractive index difference defining the semiconductor waveguide is larger for the first waveguide section than for the second waveguide section, and an output facet situated on the longitudinal axis of the semiconductor waveguide so as to emit a laser beam propagating in the semiconductor waveguide, wherein the first waveguide section is situated between the second waveguide section and the output facet and wherein the lateral refractive index difference suppresses emission of higher order transverse modes in the laser beam emitted by the output facet.

The upper surface of the semiconductor substrate has a slope descending from the projection in the second direction at an angle of 0-12 to a horizontal plane. The mesa stripe structure has an inclined surface with a slope ascending from the upper surface of the semiconductor substrate at an angle of 45-55 to the horizontal plane, the mesa stripe structure having an upright surface rising from the inclined surface at an angle of 85-95 to the horizontal plane. The buried layer is made from semiconductor with ruthenium doped therein and is in contact with the inclined surface and the upright surface. The inclined surface is as high as 80% or less of height from the upper surface of the semiconductor substrate to a lower surface of the quantum well layer and is as high as 0.3 m or more.

A semiconductor laser device includes a semiconductor layer portion having an active layer and performs multi-mode oscillation of laser light. Further, the semiconductor layer portion includes first and second regions, the second region being located closer to a facet on a laser light radiation side than the first region, the first region and the second region include a stripe region in which the laser light is guided, and an optical confinement effect of the laser light to the stripe region in a horizontal direction in the second region is less than that in the first region.

Techniques for providing curved facet semiconductor lasers. are disclosed. In one particular embodiment, the techniques may be realized as a semiconductor laser, comprising a waveguide, wherein the waveguide includes a facet formed at an edge of the semiconductor laser, and the facet has a curvature.

Apparatus comprise a semiconductor waveguide extending along a longitudinal axis and including a first waveguide section and a second waveguide section, wherein a lateral refractive index difference defining the semiconductor waveguide is larger for the first waveguide section than for the second waveguide section, and an output facet situated on the longitudinal axis of the semiconductor waveguide so as to emit a laser beam propagating in the semiconductor waveguide, wherein the first waveguide section is situated between the second waveguide section and the output facet and wherein the lateral refractive index difference suppresses emission of higher order transverse modes in the laser beam emitted by the output facet.

A semiconductor laser apparatus is provided and has a substrate, a first type cladding layer, a first type waveguide layer, an active layer, a second type waveguide layer, a second type cladding layer, and a capping layer disposed in sequence. The active layer has a light producing portion and a light emitting portion. A laser produced by the light producing portion, emits along a direction from the light producing portion toward the light emitting portion. The light emitting portion includes a first inactive region, a light emitting region, and a second inactive region. A refractive index of the light emitting region is lower than a refractive index of the first inactive region, the refractive index of the light emitting region is lower than a refractive index of the second inactive region, and width of a first part of the light emitting region continuously increases along the direction.

A semiconductor laser apparatus is provided and has a substrate, a first type cladding layer, a first type waveguide layer, an active layer, a second type waveguide layer, a second type cladding layer, and a capping layer disposed in sequence. The active layer has a light producing portion and a light emitting portion. A laser produced by the light producing portion, emits along a direction from the light producing portion toward the light emitting portion. The light emitting portion includes a first inactive region, a light emitting region, and a second inactive region. A refractive index of the light emitting region is lower than a refractive index of the first inactive region, the refractive index of the light emitting region is lower than a refractive index of the second inactive region, and width of a first part of the light emitting region continuously increases along the direction.

A laser diode apparatus has a first waveguide layer including a gain region connected in series with a second waveguide layer with a second gain region. A tunnel junction is positioned between the first and second guide layers. A single collimator is positioned in an output path of laser beams emitted from the first and second waveguide layers. The optical beam from the single collimator may be coupled into an optical fiber.

The upper surface of the semiconductor substrate has a slope descending from the projection in the second direction at an angle of 0-12 to a horizontal plane. The mesa stripe structure has an inclined surface with a slope ascending from the upper surface of the semiconductor substrate at an angle of 45-55 to the horizontal plane, the mesa stripe structure having an upright surface rising from the inclined surface at an angle of 85-95 to the horizontal plane. The buried layer is made from semiconductor with ruthenium doped therein and is in contact with the inclined surface and the upright surface. The inclined surface is as high as 80% or less of height from the upper surface of the semiconductor substrate to a lower surface of the quantum well layer and is as high as 0.3 m or more.