A quantum cascade laser includes a laser structure having an output face for emitting laser light in a first direction, and a reflecting film provided on the output face. The laser structure includes a core layer. The output face includes an end face of the core layer. The end face includes a first region and a second region that differs from the first region. The reflecting film covers the first region and does not cover the second region.

A fabrication sequence for an oxide-confined VCSEL includes the deposition of a protective coating over exposed horizontal surfaces to prevent unwanted oxide layers from being formed during the lateral oxidation process used to create the oxide aperture. By preventing the oxidation of these surfaces in the first instance, the opportunity for moisture to gain access to the active region of the VCSEL is eliminated. For example, exposed Al-containing surfaces are covered with a protective coating of dielectric material prior to initiating the conventional lateral oxidation process used to form the oxide aperture of the VCSEL. With the protective coating in place, a conventional fabrication process is resumed, and the protective coating ultimately forms part of the passivation layer used to provide electrical isolation for the final VCSEL device.

An optical device may include an array of vertical-cavity surface-emitting lasers (VCSELs) having a design wavelength, each VCSEL having an emission area. The optical device may include a first metal layer, substantially covering the array, a second metal layer substantially covering the first metal layer, and an electrical isolation layer, between the first metal layer and the second metal layer, that includes vias for electrically connecting portions of the first metal layer and portions of the second metal layer. The optical device may include a dielectric disposed over the emission area of each VCSEL. A variation in a thickness of the dielectric across at least approximately 90% of an area of the dielectric may be less than approximately 2% of the design wavelength. A depth of a well around the emission area may be equal to at least approximately 10% of a width of the emission area.

A vertical cavity surface emitting laser (VCSEL) array may comprise a first subset of VCSELs of a plurality of VCSELs, and a second subset of VCSELs of the plurality of VCSELs. One or more first beams to be emitted by the first subset of VCSELs, when the VCSEL array is powered, and one or more second beams to be emitted by the second subset of VCSELs, when the VCSEL array is powered, may have different patterns of areas of energy intensity. The different patterns of areas of energy intensity may include respective areas of high energy intensity and respective areas of low energy intensity.

A distributed feedback (DFB) semiconductor laser device includes an active layer, a first grating layer and a second grating. The first grating layer has a first grating structure with a first grating period. The second grating layer has a second grating structure with a second grating period substantially different from the first grating period. The active layer, the first grating layer and the second grating layer are vertically stacked, and the equivalent grating period of the DFB semiconductor laser device is (2P1P2)/(P1+P2), where P1 and P2 respectively represent the first grating period and the second grating period.

A semiconductor optical device may include a semiconductor substrate; a mesa stripe structure that extends in a stripe shape in a first direction on the semiconductor substrate and includes a contact layer on a top layer; an adjacent layer on the semiconductor substrate and adjacent to the mesa stripe structure in a second direction orthogonal to the first direction; a passivation film that covers at least a part of the adjacent layer; a resin layer on the passivation film; an electrode that is electrically connected to the contact layer and extends continuously from the contact layer to the resin layer; and an inorganic insulating film that extends continuously from the resin layer to the passivation film under the electrode, is spaced apart from the mesa stripe structure, and is completely interposed between the electrode and the resin layer.

A protection layer for use in fabrication of failure analysis (FA) sample is disclosed, which principally comprises a first thin film, a buffer thin film and a second thin film By forming the protection layer on a surface of a malfunction device die, a FA sample of the malfunction device die is obtained. As a result, in the case of treating the sample with a FIB thinning process, there are no cracks, distortion, and/or collapse resulted from inter-elemental isobaric interferences, stress effect or charge accumulation occurring on the surface layer of the malfunction device die because of the protection of the protection layer. On the other hand, this protection layer can also be applied to a microLED element or a VCSEL element, so as to make microLED element and the VCSEL element possess excellent stress withstanding capability.

This surface-emitting laser device comprises: a first reflective layer; an active region disposed over the first reflective layer; an aperture region which is disposed over the active region and comprises an aperture and an insulating region; a second reflective layer disposed over the aperture region; and a second electrode electrically connected to the second reflective layer. The second electrode comprises first to sixth conductive layers. The first conductive layer may comprises Ti, and the sixth conductive layer may comprise Au.

A semiconductor laser device includes: a layered structure in which a first conductivity type cladding layer, an active layer, a second conductivity type cladding layer, and a contact layer are layered in a first direction, the layered structure including a facet in a second direction intersecting the first direction, the facet outputting laser light, a non-window region, and a window region, the window region having a bandgap larger than a bandgap of the non-window region; a first electrode electrically connected to the first conductivity type cladding layer; a second electrode that is formed on the contact layer and constitutes a current path through the layered structure with the first electrode; a passivation layer formed on the facet and having a bandgap larger than the bandgap of the window region; and a dielectric reflecting coating configured to cover an opposite side of the passivation layer from the facet.

A semiconductor laser is provided that includes a semiconductor layer sequence and electrical contact surfaces. The semiconductor layer sequence includes a waveguide with an active zone. Furthermore, the semiconductor layer sequence includes a first and a second cladding layer, between which the waveguide is located. At least one oblique facet is formed on the semiconductor layer sequence, which has an angle of 45 to a resonator axis with a tolerance of at most 10. This facet forms a reflection surface towards the first cladding layer for laser radiation generated during operation. A maximum thickness of the first cladding layer is between 0.5 M/n and 10 M/n at least in a radiation passage region, wherein n is the average refractive index of the first cladding layer and M is the vacuum wavelength of maximum intensity of the laser radiation.