A semiconductor light-emitting element has a distributed Bragg reflector that is grown by depositing an InAlN layer and a GaN layer a plurality of times in that order on a semipolar plane of a semiconductor substrate, and a semiconductor structure layer that is formed on the distributed Bragg reflector and includes an active layer. The InAlN layer has a plurality of projections on an interface with the GaN layer, and the InAlN layer has a low In region which is formed at the top of each of the plurality of projections and which is lower in In composition than the remaining region.

Provided is a semiconductor light source element or an optical device including a semiconductor optical waveguide of a high-mesa semi-insulated embedded structure having a window structure made of the same material as an overclad layer at a light emission end, and a method for manufacturing thereof, in which an active layer at a portion of the window structure is removed, and then the same layer as the overclad layer is formed.

A method of forming a laser involves forming, on a substrate, a first epitaxial part of the laser that includes at least an active region layer surrounded by first and second waveguide layers. A dielectric layer is formed over the first epitaxial part. Two or more mask openings are patterned within the dielectric layer. The mask openings extend normal to a light-propagation direction of the laser and are spaced apart in the light-propagation direction of the laser. A second epitaxial part of the laser is formed in the mask openings using selective area epitaxy. The second epitaxial part includes a refractive grating with three-dimensional grating features.

A laser is provided, including: a distributed Bragg mirror; a waveguide, the laser to emit light radiation along a longitudinal direction x, and the waveguide formed at least in part in a stack of layers made of III-V materials including at least one active region to emit the light radiation, the mirror including lateral corrugations distributed periodically along the direction x in a period Λ, the corrugations being carried by at least a lateral plane xz defined by the direction x and a first transverse direction z normal to the direction x, the corrugations having a dimension d along a second transverse direction y normal to the direction x; and a top electrode arranged on the waveguide along the direction z, the corrugations being partly located at lateral flanks of the top electrode, extending parallel to the plane xz, and extending only on the lateral flanks of the top electrode.

Electro-absorption modulators (EAM) and monolithically integrated electro-absorption modulated lasers (EML) and methods of fabrication are disclosed. Vertically stacked waveguides for a distributed feedback (DFB) laser, an electro-absorption modulator (EAM) and a passive output waveguide are vertically integrated, and the DFB laser, EAM and output waveguide are optically coupled using laterally tapered vertical optical couplers. Laterally tapered vertical optical couplers provides an alternative to conventional butt-coupling of a laser and EAM, offering improved reliability for high power operation over extended lifetimes. Optionally, the EML comprises monolithically integrated electronic circuitry, e.g., driver and control electronics for the DFB laser and EAM. Beneficially, integrated EAM driver and control circuitry comprises a high-speed electro-optical control loop for very high-speed linearization and temperature compensation, e.g. to enable advanced modulation schemes, such as PAM-4 and DP-QPSK, for analog optical data center interconnect applications. Some embodiments are compatible with fabrication using a single epitaxial growth.

A method for forming a Bragg reflector includes after forming first trenches in the stack, which are intended to form structures of the distributed Bragg reflector, forming a sacrificial interlayer at least in the first trenches, depositing a second masking layer at least inside the first trenches, forming second trenches intended to form sidewalls of the laser, removing the second masking layer from inside the first trenches, removing said sacrificial interlayer so as to remove, by lift-off, residues of the second masking layer that remain inside the first trenches, and filling said first trenches with at least one metal material.

A high-power semiconductor chip and a preparation method therefor. The semiconductor chip comprises: a substrate (1), a lower confinement layer (2), a lower waveguide layer (3), an active layer (4), an upper waveguide layer (5), a lateral grating layer (10), an upper confinement layer (6), a contact layer (7), a current isolation dielectric layer (8) and a metal layer (9), sequentially arranged from bottom to top, wherein the lateral grating layer (10) comprises a plurality of groups of lateral gratings; the plurality of groups of lateral gratings are sequentially arranged in a first direction; the periods of the plurality of groups of lateral gratings are different from each other; each group of lateral gratings comprises a plurality of gratings; the plurality of gratings are arranged in a second direction; and the first direction intersects with the second direction. Providing a lateral grating layer (10) in a waveguide improves the propagation loss of the high-order lateral light mode in the waveguide, and achieves the aim of suppressing the lasing of the high-order lateral light mode; and providing a plurality of groups of gratings with different periods suppresses the lasing of an intensity oscillation light mode caused by single grating gain modulation and refractive index modulation, achieves the effect of suppressing lateral light intensity periodic oscillation and eliminates the formation of far-field double humps.

What is provided here are: a step of forming a first semiconductor layer on a base member; a step of forming a mask on the first semiconductor layer; a step of etching the first semiconductor layer by using the mask, to thereby form a semiconductor structure; a step of forming a second semiconductor layer in a region abutting on a side surface of the semiconductor structure, said second semiconductor layer having a convex portion abutting to the mask; a convex-portion removing step of removing the convex portion by supplying an etching gas thereto; and a regrown-layer forming step of supplying a material gas onto the semiconductor structure and the second semiconductor layer, to thereby form a regrown layer; wherein the convex-portion removing step and the regrown-layer forming step are executed in a same manufacturing apparatus.

Semiconductor laser architectures that provide weak index guiding of interband cascade lasers (ICLs) processed on a native III-V substrate and of ICLs grown on GaAs or integrated on GaAs by heterogeneous bonding. Weak index guiding of a ridge waveguide semiconductor laser can enhance the stability of lasing in the fundamental lateral mode, so as to allow a wider ridge to maintain stable single-lateral-mode operation.

A semiconductor optical device in which a light emitting region that emits light and a reflecting region that reflects the light to the light emitting region side are integrated includes a core layer that is provided in the light emitting region, and a waveguide layer that is provided in the reflecting region, that is optically coupled to the core layer, and that has a band gap that is larger than energy of the light. The reflecting region has a first thyristor that overlaps the waveguide layer in a direction that intersects a propagation direction of the light.