A semiconductor optical device includes an element structure layer that includes a mesa stripe extending in a first direction; an electrode film that covers at least an upper surface of the mesa stripe; an electrode pad portion that covers a part of a first region positioned in a second direction, intersecting the first direction, relative to the mesa stripe on an upper surface of the element structure layer and is electrically connected to the electrode film; a first dummy electrode that covers another part of the first region and is electrically insulated from the electrode film; and a second dummy electrode that covers at least a part of a second region positioned in a third direction, opposite to the second direction, relative to the mesa stripe on the upper surface of the element structure layer and is electrically insulated from the electrode film, wherein the first dummy electrode includes a first portion disposed in the first direction relative to the electrode pad portion and a second portion disposed in a fourth direction, opposite to the first direction, relative to the electrode pad portion.

A light emitting device is provided that makes it possible to reduce absorption of light by an electrode. The light emitting device includes a substrate, and a laminated structure provided to the substrate, wherein the laminated structure includes a first semiconductor layer, a second semiconductor layer different in conductivity type from the first semiconductor layer, and an active layer disposed between the first semiconductor layer and the second semiconductor layer, the first semiconductor layer is disposed between the substrate and the active layer, a recessed part is disposed at an opposite side to the substrate side of the laminated structure, the recessed part is provided with a low refractive-index part lower in refractive index than the second semiconductor layer, a depth of the recessed part is no larger than a distance between a surface at an opposite side to the substrate side of the laminated structure and the active layer, and an electrode is disposed at an opposite side to the substrate side of the laminated structure.

A non-planarized VCSEL can include: a blocking region over or under an active region, the blocking region having a first thickness; one or more conductive channel cores in the blocking region, the one or more conductive channel cores having a second thickness that is larger than the first thickness, wherein the blocking region is defined by having an implant and the one or more conductive channel cores are devoid of the implant, wherein the blocking region is lateral the one or more conductive channel cores, the blocking region and one or more conductive channel cores being an isolation region; and a non-planarized semiconductor region of one or more non-planarized semiconductor layers over the isolation region. The VCSEL can include a planarized bottom mirror region below the active region and a non-planarized top mirror region above the isolation region, or a non-planarized bottom mirror region below the active region.

In a semiconductor laser according to an embodiment of the present disclosure, a ridge part has a structure in which a plurality of gain regions and a plurality of Q-switch regions are each disposed alternately with each of separation regions being interposed therebetween in an extending direction of the ridge part. The separation regions each have a separation groove that separates from each other, by a space, the gain region and the Q-switch region adjacent to each other. The separation groove has a bottom surface at a position, in a second semiconductor layer, higher than a part corresponding to a foot of each of both sides of the ridge part.

A wavelength tunable laser includes: a heating layer, a dielectric layer, reflectors, a transport layer, a support layer, and a substrate layer. The heating layer is located above the transport layer; the transport layer is located above the support layer, and the transport layer includes an upper cladding layer, a waveguide layer, and a lower cladding layer from top to bottom; the reflector is located in the transport layer; the support layer has a protection structure, where the protection structure forms a hollow structure together with the transport layer and the substrate layer, and the hollow structure has a support structure; and the substrate layer is located below the support layer. The heating layer, the reflector, and a part of the transport layer form a suspended structure to prevent heat dissipation. Thus thermal tuning efficiency can be improved, and power consumption can be lowered.

An etched planarized VCSEL includes: an active region; a blocking region over the active region, and defining apertures therein; and conductive channel cores in the apertures, wherein the conductive channel cores and blocking region form an isolation region. A method of making the VCSEL includes: forming the active region; forming the blocking region over the active region; etching the apertures in the blocking region; and forming the conductive channel cores in the apertures of the blocking region. Another etched planarized VCSEL includes: an active region; a conductive region over the active region, and defining apertures therein; and blocking cores in the apertures, wherein the blocking cores and conductive region form an isolation region. A method of making the VCSEL includes: forming the active region; forming the conductive region over the active region; etching the apertures in the conductive region; and forming the blocking cores in the apertures of the conductive region.

A semiconductor device according to the present invention includes a substrate, a semiconductor laser that is provided on an upper surface of the substrate and emits laser light, a waveguide having a first conductive layer provided on the upper surface of the substrate, and a waveguide layer that is provided on the first conductive layer and guides the laser light and an embedment layer provided on the upper surface of the substrate and surrounding the semiconductor laser and the waveguide, wherein on both sides of an end part, of the waveguide, which is connected to the semiconductor laser, an exposed part is provided in which the substrate is exposed from the embedment layer by the embedment layer separated in a waveguide direction of the waveguide, and in the end part, a separation region is provided in which the first conductive layer is separated in the waveguide direction.

In a semiconductor laser according to an embodiment of the present disclosure, a ridge part has a structure in which a plurality of gain regions and a plurality of Q-switch regions are each disposed alternately with each of separation regions being interposed therebetween in an extending direction of the ridge part. The separation regions each have a separation groove that separates from each other, by a space, the gain region and the Q-switch region adjacent to each other. The separation groove has a bottom surface at a position, in a second semiconductor layer, higher than a part corresponding to a foot of each of both sides of the ridge part. The semiconductor laser includes an electrode provided over the bottom surface of each separation groove with an insulating layer being interposed therebetween.

A reflector structure for a tunable laser and a tunable laser. A super structure grating is used as a reflector structure, and a suspended structure is formed around a region in which the super structure grating is located, to implement, using the suspended structure, thermal isolation around the region in which the super structure grating is located, and increase thermal resistance, such that less heat is lost, and heat is concentrated in the region in which the super structure grating is located, thereby improving thermal tuning efficiency of the reflector structure. Moreover, lateral support structures are disposed on two sides of the suspended structure, to provide a mechanical support for the suspended structure. In addition, regions in the super structure grating that correspond to any two lateral support structures on a same side of the suspended structure fall at different locations in a spatial period of the super structure grating.

A semiconductor optical integrated device includes: a substrate; at least a lower cladding layer, a waveguide core layer, and an upper cladding layer sequentially layered on the substrate, a buried hetero structure waveguide portion having a waveguide structure in which a semiconductor cladding material is embedded near each of both sides of the waveguide core layer; and a ridge waveguide portion having a waveguide structure in which a semiconductor layer including at least the upper cladding layer protrudes in a mesa shape. Further, a thickness of the upper cladding layer in the buried hetero structure waveguide portion is greater than a thickness of the upper cladding layer in the ridge waveguide portion.