A semiconductor optical element includes: a first conductivity type semiconductor substrate; and a laminated body disposed on the first conductivity type semiconductor substrate. The laminated body includes, in the following order from a side of the first conductivity type semiconductor substrate: a first conductivity type semiconductor layer; an active layer; a second conductivity type semiconductor layer; and a second conductivity type contact layer. The second conductivity type semiconductor layer includes: a carbon-doped semiconductor layer in which carbon is doped as a dopant in a compound semiconductor; and a group 2 element-doped semiconductor layer in which a group 2 element is doped as a dopant in a compound semiconductor. The carbon-doped semiconductor layer is disposed at a position closer to the active layer than the group 2 element-doped semiconductor layer.

A semiconductor laser device lases in a multiple transverse mode and includes a stacked structure where a first conductivity-side semiconductor layer, an active layer, and a second conductivity-side semiconductor layer are stacked above a substrate. The second conductivity-side semiconductor layer includes a current block layer having an opening that delimits a current injection region. Side faces as a pair are formed in portions of the stacked structure that range from part of the first conductivity-side semiconductor layer to the second conductivity-side semiconductor layer. The active layer has a second width greater than a first width of the opening. The side faces in at least part of the first conductivity-side semiconductor layer are inclined to the substrate. A maximum intensity position in a light distribution of light guided in the stacked structure, in a direction of the normal to the substrate, is within the first conductivity-side semiconductor layer.

Edge-emitting laser diodes having mirror facets include passivation coatings that are conditioned using an ex-situ process to condition the insulating material used to form the passivation layer. An external energy source (laser, flash lamp, e-beam) is utilized to irradiate the material at a given dosage and for a period of time sufficient to condition the complete thickness of passivation layer. This ex-situ laser treatment is applied to the layers covering both facets of the laser diode (which may comprise both the passivation layers and the coating layers) to stabilize the entire facet overlay. Importantly, the ex-situ process can be performed while the devices are still in bar form.

A semiconductor optical element includes: a first conductivity type semiconductor substrate; and a laminated body disposed on the first conductivity type semiconductor substrate. The laminated body includes, in the following order from a side of the first conductivity type semiconductor substrate: a first conductivity type semiconductor layer; an active layer; a second conductivity type semiconductor layer; and a second conductivity type contact layer. The second conductivity type semiconductor layer includes: a carbon-doped semiconductor layer in which carbon is doped as a dopant in a compound semiconductor; and a group 2 element-doped semiconductor layer in which a group 2 element is doped as a dopant in a compound semiconductor. The carbon-doped semiconductor layer is disposed at a position closer to the active layer than the group 2 element-doped semiconductor layer.

A semiconductor laser device, which outputs laser light, includes: a substrate; an n-type semiconductor layer disposed above the substrate; a light emitting layer disposed above the n-type semiconductor layer; a p-type semiconductor layer disposed above the light emitting layer; and at least one p electrode disposed above the p-type semiconductor layer. At least one groove is formed that extends from an upper surface of the p-type semiconductor layer to reach a lower surface of the light emitting layer, and extends in a resonance direction of the laser light. A remaining length, which is a distance between an output end face from which the laser light is outputted and a portion of each groove that is closest to the at least one p electrode, is longer than a non-injection region length, which is a distance between the output end face and the at least one p electrode.

A semiconductor laser comprises a ridge formed on an n-type semiconductor substrate, a buried layer buried so as to cover both sides in an x-direction perpendicular to a y-direction, which is the direction in which the ridge extends. In a positive side of a z-direction that is the direction in which the ridge protrudes and the positive side of the buried layer in the z-direction, provided are a p-type second cladding layer, a p-type contact layer, a surface-side electrode that is connected to the p-type contact layer, and a semi-insulating layer that is formed on an outer edge separated from the ridge in the x-direction. The semi-insulating layer or the front surface-side electrode is formed on sides toward x-direction ends of the semiconductor laser on the positive side in the z-direction.

A method for manufacturing a surface emitting laser made of a group-III nitride semiconductor by an MOVPE method includes: (a) growing a first cladding layer of a first conductive type on a substrate; (b) growing a first optical guide layer of the first conductive type on the first cladding layer; (c) forming holes having a two-dimensional periodicity in a plane parallel to the first optical guide layer, in the first optical guide layer by etching; (d) supplying a gas containing a group-III material and a nitrogen source and performing growth to form recessed portions having a facet of a predetermined plane direction above openings of the holes, thereby closing the openings of the holes; and (e) planarizing the recessed portions by mass transport, after the openings of the holes have been closed, wherein after the planarizing at least one side surface of the holes is a {10-10} facet.

A semiconductor optical device may include a semiconductor substrate; a mesa stripe structure that extends in a stripe shape in a first direction on the semiconductor substrate and includes a contact layer on a top layer; an adjacent layer on the semiconductor substrate and adjacent to the mesa stripe structure in a second direction orthogonal to the first direction; a passivation film that covers at least a part of the adjacent layer; a resin layer on the passivation film; an electrode that is electrically connected to the contact layer and extends continuously from the contact layer to the resin layer; and an inorganic insulating film that extends continuously from the resin layer to the passivation film under the electrode, is spaced apart from the mesa stripe structure, and is completely interposed between the electrode and the resin layer.

A semiconductor laser is disclosed. Trim loss region is provided in inner ridge region of surface of transmission layer facing away from substrate, blind hole is provided in trim loss region, and distance from bottom surface of blind hole to surface of second cladding layer facing to substrate is smaller than evanescent wave length in transmission layer. Blind hole can affect optical field characteristics of light transmission in semiconductor laser by affecting evanescent wave. A method for fabricating a semiconductor laser is also provided.

An integrated semiconductor optical amplifier-laser diode (SOA-LD) device includes a laser diode (LD) section fabricated on a substrate, a semiconductor optical amplifier (SOA) section fabricated on the substrate adjacent to the LD section; and a trench formed at least partially between the LD section and SOA section to electrically isolate the LD section and the SOA section while maintaining optical coupling between the LD section and the SOA section.