A method of fabricating an optoelectronic component, performed on a multi-layered wafer disposed on a substrate. The method comprises the steps of: etching the multi-layered wafer, thereby defining a slab and a multi-layered ridge, the slab having an upper surface below the ridge and being located between the multi-layered ridge and the substrate; selectively epitaxially growing a III-V semiconductor cladding adjacent to a first and second sidewall of the ridge, the cladding layer extending from the upper surface of the slab along the first and second sidewalls, and thereby cladding an optically active waveguide within the multi-layered ridge; and providing a first and second electrical contact, which electrically connect to a layer of the multi-layered ridge and the slab respectively.

A quantum cascade laser device includes a semiconductor substrate, an active layer provided on the semiconductor substrate, and an upper clad layer provided on a side of the active layer opposite to the semiconductor substrate side and having a doping concentration of impurities of less than 1×10.sup.17 cm.sup.−3. Unit laminates included in the active layer each include a first emission upper level, a second emission upper level, and at least one emission lower level in their subband level structure. The active layer is configured to generate light having a center wavelength of 10 μm or more due to electron transition between at least two levels of the first emission upper level, the second emission upper level, and the at least one emission lower level in the light emission layer in each of the unit laminates.

An optoelectronic device, including: a laser source, including a semiconductor membrane, which rests on a first dielectric layer, and which is formed from a lateral segment doped n-type, a lateral segment doped p-type, and an optically active central segment located between and in contact with the doped lateral segments to form a lateral p-i-n junction lying parallel to the main plane. The semiconductor membrane is produced based on crystalline GaAs, the central segment includes GaAs-based quantum dots, and the doped lateral segments are produced based on AlxGa1-xAs with a proportion of aluminium x comprised between 0.05 and 0.30.

A method for manufacturing a GaN-based surface-emitting laser by an MOVPE includes: growing a first cladding layer with a {0001} growth plane; growing a guide layer on the first cladding layer; forming holes which are two-dimensionally periodically arranged within the guide layer; etching the guide layer by ICP-RIE using a chlorine-based gas and an argon; supplying a gas containing a nitrogen to cause mass-transport, and then supplying the group-III gas for growth, whereby a first embedding layer closing openings of the holes is formed to form a photonic crystal layer; and growing an active layer and a second cladding layer on the first embedding layer, The step includes a step of referring to already-obtained data on a relationship of an attraction voltage and a ratio of gases in the ICP-RIE with a diameter distribution of air holes embedded, and applying the attraction voltage and the ratio to the ICP-RIE.

A laser diode including a double heterostructure comprising a top layer, a buffer layer formed on a substrate, and an intrinsic active layer formed between the top layer and the buffer layer. The top layer and the buffer layer have opposite types of conductivity. The active layer has a bandgap smaller than that of the buffer layer or the top layer. The double heterostructure includes Ge, SiGe, GeSn, and/or SiGeSn materials.

A semiconductor laser element includes a substrate and a semiconductor stack. The semiconductor stack includes an N-side semiconductor layer, an active layer, a P-side semiconductor layer, and a P-type contact layer. The semiconductor stack includes two end faces. Laser light resonates between the two end faces. The semiconductor stack includes: a ridge portion; and a bottom portion surrounding the ridge portion in a top view of the semiconductor stack. The ridge portion protrudes upward from the bottom portion, is spaced apart from the two end faces, and includes at least a portion of the P-type contact layer. A current injection window is provided only on the ridge portion out of a top face of the semiconductor stack, the current injection window being a region into which a current is injected. A distance from a top face of the active layer to the bottom portion is constant.

A vertical-cavity surface-emitting laser (VCSEL) has a substrate formed of GaAs. A pair of mirrors is provided wherein one of the pair of mirrors is formed on the substrate. A tunnel junction is formed between the pair of mirrors.

An optical semiconductor device includes a semiconductor multilayer structure, an active region interposed between a first facet on a light emitting side and a second facet opposing to the first facet, and a first electrode layer provided on a top of the semiconductor multilayer structure and a second electrode layer provided on a bottom of the semiconductor multilayer structure; and an electrical connection region connected to at least one of the first electrode layer and the second electrode layer of the optical semiconductor device and used for injecting a current to the active region, and α>β and β>0 are satisfied where α is the contact area included in a half region on the first facet side in a top area of the optical semiconductor device and β is the contact area included in a half region on the second facet side.

A semiconductor light-emitting element includes: a substrate; an n-type clad layer above the substrate; an active layer above the n-type clad layer; and a p-type clad layer above the active layer. The active layer includes: a well layer; an n-side first barrier layer on an n-type clad layer side of the well layer; and a p-side barrier layer on a p-type clad layer side of the well layer. The p-side barrier layer comprises In. The n-side first barrier layer has an In composition ratio lower than an In composition ratio of the p-side barrier layer. The n-side first barrier layer has a band gap energy smaller than a band gap energy of the p-side barrier layer.

A semiconductor light-emitting element includes a light emission layer including a group III nitride semiconductor; an electron barrier layer disposed above the light emission layer and including a group III nitride semiconductor containing Al; and a p-type clad layer disposed above and in contact with the electron barrier layer, wherein the electron barrier layer and the p-type clad layer contain Mg as a dopant, and the p-type clad layer includes a high carbon concentration region containing carbon and a low carbon concentration region having a carbon concentration lower than a carbon concentration of the high carbon concentration region, in a stated order from an electron barrier layer side.