A method for manufacturing a GaN-based surface-emitting laser by an MOVPE includes: (a) growing a first cladding layer with a {0001} growth plane; (b) growing a guide layer on the first cladding layer; (c) forming holes which are two-dimensionally periodically arranged within the guide layer; (d) etching the guide layer by ICP-RIE using a chlorine-based gas and an argon; (e) 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 (f) growing an active layer and a second cladding layer on the first embedding layer, The step (d) 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.

Methods are provided for modifying the emission wavelength of a semiconductor quantum well laser diode, e.g. by blue shifting the emission wavelength. The methods can be applied to a variety of semiconductor quantum well laser diodes, e.g. group III-V semiconductor quantum wells. The group III-V semiconductor can include AlSb, AlAs, Aln, AlP, BN, GaSb, GaAs, GaN, GaP, InSb, InAs, InN, and InP, and group III-V ternary semiconductors alloys such as Al.sub.xGa.sub.i.xAs. The methods can results in a blue shifting of about 20 meV to 350 meV, which can be used for example to make group III-V semiconductor quantum well laser diodes with an emission that is orange or yellow. Methods of making semiconductor quantum well laser diodes and semiconductor quantum well laser diodes made therefrom are also provided.

A vertical external-cavity surface-emitting laser (VECSEL) whose blueshift is reduced also in a high intensity range of emitted laser light is realized. A surface-emitting device for VECSEL includes a base substrate made of GaN and c-axis oriented, and an emitter structure formed of a group 13 nitride semiconductor and provided on the base substrate. The emitter structure is formed of unit deposition parts, each of which is provided on the base substrate and includes a DBR layer having a distributed Bragg reflection structure and an active layer that has a multiple quantum well structure and generates excitation emission in response to irradiation with external laser light. A c-axis orientation of each of the unit deposition parts conforms to the c-axis orientation of the base substrate located directly below the unit deposition parts. Grooves are formed between the unit deposition parts.

A reflector includes a low refractive index layer and a high refractive index layer. The low refractive index layer has a first average refractive index and has a laminated structure in which an AlN layer and a GaN layer are alternately laminated. The high refractive index layer has a second average refractive index higher than the first average refractive index and includes an InGaN layer.

A group III-nitride semiconductor device comprises a light emitting semiconductor structure comprising a p-type layer and an n-type layer operable as a light emitting diode or laser. On top of the p-type layer there is arranged an n+ or n++-type layer of a group III-nitride, which is transparent to the light emitted from the underlying semiconductor structure and of sufficiently high electrical conductivity to provide lateral spreading of injection current for the light-emitting semiconductor structure.

A semiconductor light emitting device includes: a nitride semiconductor light emitting element including a nitride semiconductor substrate having a polar or semipolar surface and a nitride semiconductor multilayer film stacked on the polar or semipolar surface; and a mounting section to which the element is mounted. The nitride semiconductor multilayer film includes an electron block layer. The electron block layer has a smaller lattice constant than the nitride semiconductor substrate. The mounting section includes at least a first mounting section base. The first mounting section base is located close to the nitride semiconductor light emitting element. The first mounting section base has a lower thermal expansion coefficient than the nitride semiconductor multilayer film. The first mounting section base has a lower thermal conductivity than the nitride semiconductor multilayer film.

A semiconductor device according to the present application includes a semiconductor substrate, an n-type first cladding layer provided on the semiconductor substrate, an n-type second cladding layer provided on the first cladding layer, an active layer provided on the second cladding layer, a p-type third cladding layer provided on the active layer, a surface electrode provided above the third cladding layer, a back surface electrode provided below the semiconductor substrate and a p-type diffusion prevention layer provided between the first cladding layer and the second cladding layer.

A semiconductor laser element includes: an n-side semiconductor layer formed of a nitride semiconductor; an active layer disposed on or above the n-side semiconductor layer and formed of a nitride semiconductor; a p-side semiconductor layer disposed on the active layer, formed of a nitride semiconductor, and including: an undoped first part disposed in contact with an upper face of the active layer and comprising at least one semiconductor layer, an electron barrier layer disposed in contact with an upper face of the first part, containing a p-type impurity, and having a band gap energy that is larger than a band gap energy of the first part, and a second part disposed in contact with the upper face of the electron barrier layer and comprising at least one p-type semiconductor layer containing a p-type impurity; and a p-electrode disposed in contact with the upper face of the second part.

A method for the reuse of gallium nitride (GaN) epitaxial substrates uses band-gap-selective photoelectrochemical (PEC) etching to remove one or more epitaxial layers from bulk or free-standing GaN substrates without damaging the substrate, allowing the substrate to be reused for further growth of additional epitaxial layers. The method facilitates a significant cost reduction in device production by permitting the reuse of expensive bulk or free-standing GaN substrates.

A method and device for emitting electromagnetic radiation at high power using nonpolar or semipolar gallium containing substrates such as GaN, AlN, InN, InGaN, AlGaN, and AlInGaN, is provided. In various embodiments, the laser device includes plural laser emitters emitting green or blue laser light, integrated a substrate.