A nitride semiconductor laser device at least includes a ridge part disposed on a second-conductivity-type semiconductor layer, a conductive oxide layer covering the upper surface of the ridge part and portions of opposite side surfaces of the ridge part, a dielectric layer covering a portion of the conductive oxide layer, and a first metal layer covering the conductive oxide layer and the dielectric layer, wherein a portion of the conductive oxide layer disposed on the upper surface of the ridge part is exposed through the dielectric layer and covered with the first metal layer.

A device that includes a metal(III)-polar III-nitride substrate having a first surface opposite a second surface, a tunnel junction formed on one of the first surface or a buffer layer disposed on the first surface, a p-type III-nitride layer formed directly on the tunnel junction, and a number of material layers; a first material layer formed on the p-type III-nitride layer, each subsequent layer disposed on a preceding layer, where one layer from the number of material layers is patterned into a structure, that one layer being a III-nitride layer. Methods for forming the device are also disclosed.

Provided is a nitride semiconductor laser element which includes: a stacked structure including a plurality of semiconductor layers including a light emitting layer, the stacked structure including a pair of resonator end faces located on opposite ends; and a protective film including a dielectric body and disposed on at least one of the pair of resonator end faces. The protective film includes a first protective film (a first emission surface protective film), a second protective film (a second emission surface protective film), and a third protective film (a third emission surface protective film) disposed in stated order above the stacked structure. The first protective film is amorphous, the second protective film is crystalline, and the third protective film is amorphous.

A laser heating device for mounting LED includes: a carrier substrate, an optical module and a laser generation module. The carrier substrate for carrying a circuit substrate includes a plurality of conductive pads, a plurality of conductors, and a plurality of LED chips. The conductors are respectively disposed on the conductive pads, and each of the LED chips is disposed in at least two of the corresponding conductors. The optical module is disposed above the carrier substrate. The laser generation module is adjacent to the optical module to provide a laser source having a first predetermined range. The conductor is irradiated by the laser source to mount the LED chip, the first predetermined range of the laser source is optically adjusted by the optical module to form a second predetermined range, and the first predetermined range is greater than, less than or equal to the second predetermined range.

A nitride semiconductor light-emitting element includes an n-type cladding layer including n-type AlGaN and having a first Al composition ratio, and a multiple quantum well layer in which a plurality (number N) of barrier layers including AlGaN having a second Al composition ratio more than the first Al composition ratio and a plural (number N) well layers having an Al composition ratio less than the second Al composition ratio are stacked alternately in this order, wherein the second Al composition ratio of the plurality of barrier layers of the multiple quantum well layer increases at a predetermined increase rate from an n-type cladding layer side toward an opposite side to the n-type cladding layer side.

A method for manufacturing a surface emitting laser made of a group-III nitride semiconductor by an MOVPE method includes: (a) of growing a first cladding layer of a first conductive type on a substrate; (b) of growing a first optical guide layer of the first conductive type on the first cladding layer; (c) of 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) of planarizing the recessed portions by mass transport, after the openings of the holes have been closed, wherein after said the planarizing, at least one side surface of the holes is a {10-10} facet.

A nitride semiconductor multilayer structure includes a first nitride semiconductor layer; a second nitride semiconductor layer; and a third nitride semiconductor layer formed between the first nitride semiconductor layer and the second nitride semiconductor layer. The third nitride semiconductor layer includes a first region and a second region that surrounds the first region in a same plane, and an indium content of the second region is lower than an indium content of the first region.

A nitride semiconductor laser device at least includes a ridge part disposed on a second-conductivity-type semiconductor layer, a conductive oxide layer covering the upper surface of the ridge part and portions of opposite side surfaces of the ridge part, a dielectric layer covering a portion of the conductive oxide layer, and a first metal layer covering the conductive oxide layer and the dielectric layer, wherein a portion of the conductive oxide layer disposed on the upper surface of the ridge part is exposed through the dielectric layer and covered with the first metal layer.

Single-mode quantum cascade semiconductor lasers are provided. The lasers comprise a laser element, the laser element comprising a quantum cascade active layer; an upper cladding layer over the quantum cascade active layer; and a lower cladding layer under the quantum cascade active layer, wherein the quantum cascade active layer, the upper cladding layer and the lower cladding layer define a guided optical mode. The quantum cascade active layer and the upper and lower cladding layers are shaped in the form of a ridge structure having a front face, a back face opposite the front face, and a lasing face through which laser emission exits the ridge structure, the ridge structure configured such that the laser emission has a single-lobe, far-field beam pattern from the ridge structure comprising certain sections, including tapered sections, collateral sections, or both.

Alight source device includes a resonator having first and second mirrors, a gain medium disposed between the first and second mirrors and including a first semiconductor portion, an active layer, and a second semiconductor portion arranged in this order in a direction perpendicular to an optical axis of the resonator, and having first and second principal surfaces respectively located on sides of the first and second semiconductor portions opposite to sides on which the active layer is provided, a first heat dissipation member located on a first principal surface side of the gain medium, and a second heat dissipation member located on a second principal surface side of the gain medium. The resonator and the gain medium are arranged such that the optical axis passes through the gain medium.