A structure of Vertical Cavity Surface-Emitting Laser (VCSEL) comprises an ion-implanted region with gas-furnace configuration arranged in the second mirror layer around a laser light output window, in order to retain several conductive passages between the inner and outer rims of the ion-implanted region, so as to let the aperture of the inner rim of the metal layer (that is, the aperture of the output window) be expanded without loss of resistance. Not only the shading effect can be removed, the spectrum width suppression function can be preserved, but also various photoelectric characteristics such as transmission eye diagram and photoelectric curve linearity can be improved, in addition, high-speed transmission characteristics can also be optimized.

A light emitting element array includes: a light emitting element group that includes plural light emitting elements; and plural lenses that are provided, corresponding to the plural light emitting elements, on a light emitting surface side of the plural light emitting elements, and that deflects light emitted from the plural light emitting elements according to a positional relation with the plural light emitting elements. Distances between central axes of light emission of the plural light emitting elements and central axes of the plural lenses corresponding to the plural light emitting elements increase from a center side of the light emitting element group toward an end side of the light emitting element group, and a degree of change in the distances decreases from the center side of the light emitting element group toward the end side of the light emitting element group.

A semiconductor laser including an active zone and a waveguide, wherein the active zone includes an active layer configured to generate electromagnetic radiation during operation of the semiconductor laser, the waveguide is configured to guide the electromagnetic radiation generated during operation of the semiconductor laser within the semiconductor laser, the waveguide includes a subregion formed from a compound semiconductor material, wherein a proportion of a material of the compound semiconductor material gradually increases in the entire subregion along the vertical direction toward the active zone so that a refractive index of the subregion gradually decreases toward the active zone, and the proportion is an aluminum proportion or a phosphorus proportion.

A semiconductor laser device is provided with a semiconductor layer including an active layer and a plurality of cladding layers sandwiching the active layer. The active layer includes a stripe-shaped active region, a pair of first refractive index regions and a pair of second refractive index regions sandwiching the active layer and the pair of first refractive index regions. When is the laser oscillation wavelength, n.sub.a is the effective refractive index of the active region, n.sub.c is the effective refractive index of the first refractive index regions, n.sub.t is the effective refractive index of the second refractive index regions, w is the width of the active region, and m is a positive integer, the semiconductor laser device satisfies n.sub.a>n.sub.t>n.sub.c, and the conditions of equations (5), (8) and (9).

A single chip including an optoelectronic device on the semiconductor layer in a first region, the optoelectronic device comprises a bottom cladding layer, an active region, and a top cladding layer, wherein the bottom cladding layer is above and in direct contact with the semiconductor layer, the active region is above and in direct contact with the bottom cladding layer, and the top cladding layer is above and in direct contact with the active region, a silicon device on the substrate extension layer in a second region, a device insulator layer substantially covering both the optoelectronic device in the first region and the silicon device in the second region, and a waveguide embedded within the device insulator layer in direct contact with a sidewall of the active region of the optoelectronic device.

A semiconductor device includes a substrate comprising a layer made of Ge and a semiconductor multilayer structure grown on the layer made of Ge. The semiconductor multilayer structure includes at least one first layer comprising a material selected from a group consisting of Al.sub.xGa.sub.1-xAs, Al.sub.xGa.sub.1-x-yIn.sub.yAs, Al.sub.xGa.sub.1-x-yIn.sub.yAs.sub.1-zP.sub.z, Al.sub.xGa.sub.1-x-yIn.sub.yAs.sub.1-zN.sub.z, and Al.sub.xGa.sub.1-x-yIn.sub.yAs.sub.1-z-cN.sub.zP.sub.c, Al.sub.xGa.sub.1-x-yIn.sub.yAs.sub.1-z-cN.sub.zSb.sub.c, and Al.sub.xGa.sub.1-x-yIn.sub.yAs.sub.1-z-cP.sub.zSb.sub.c, wherein for any material a sum of the contents of all group-III elements equals 1 and a sum of the contents of all group-V elements equals 1. The semiconductor multilayer structure also includes at least one second layer comprising a material selected from a group consisting of GaInAsNSb, GaInAsN, AlGaInAsNSb, AlGaInAsN, GaAs, GaInAs, GaInAsSb, GaInNSb, GaInP, GaInPNSb, GaInPSb, GaInPN, AlInP, AlInPNSb, AlInPN, AlInPSb, AlGaInP, AlGaInPNSb, AlGaInPN, AlGaInPSb, GaInAsP, GaInAsPNSb, GaInAsPN, GaInAsPSb, GaAsP, GaAsPNSb, GaAsPN, GaAsPSb, AlGaInAs and AlGaAs.

A pyrolytic graphite (PG) substrate and laser diode package includes a substrate body having a PG crystalline structure with a basal plane oriented at a pre-determined orientation angle as measured from a longitudinal axis of a heat generating material, such as a laser diode, mounted on a surface of the PG substrate, so that a coefficient of thermal expansion (CTE) of the PG substrate is substantially matched with a CTE of the material.

In an optical module (first module (1)), a plurality of semiconductor laser elements (a first semiconductor laser element (21) through a third semiconductor laser element (23)) that output light of wavelengths which are different from each other from light emitting points are mounted on a base member (10). The base member (10) has a reference surface (11) serving as a reference in a height direction (Z) and a mounting surface (a first mounting surface (12a) and a second mounting surface (12b)) on which the semiconductor laser elements are mounted. At least some of the plurality of semiconductor laser elements are different from each other in a height (a first light emission height (TL1) through a third light emission height (TL3)) from a surface in contact with the mounting surface to the light emitting points, and are substantially equal in a height (reference height (HL)) from the reference surface to the light emitting points.

In a semiconductor laser according to an embodiment of the present disclosure, a ridge part has a structure in which a plurality of gain regions and a plurality of Q-switch regions are each disposed alternately with each of separation regions being interposed therebetween in an extending direction of the ridge part. The separation regions each have a separation groove that separates from each other, by a space, the gain region and the Q-switch region adjacent to each other. The separation groove has a bottom surface at a position, in a second semiconductor layer, higher than a part corresponding to a foot of each of both sides of the ridge part.

In an embodiment, a device includes: a first reflective structure including first doped layers of a semiconductive material, alternating ones of the first doped layers being doped with a p-type dopant; a second reflective structure including second doped layers of the semiconductive material, alternating ones of the second doped layers being doped with a n-type dopant; an emitting semiconductor region disposed between the first reflective structure and the second reflective structure; a contact pad on the second reflective structure, a work function of the contact pad being less than a work function of the second reflective structure; a bonding layer on the contact pad, a work function of the bonding layer being greater than the work function of the second reflective structure; and a conductive connector on the bonding layer.