Abstract: An edge-emitting semiconductor laser and fabrication method is disclosed that includes a second, passive waveguide and cladding layer disposed above the multi-layer arrangement of a first waveguiding layer and a first cladding layer. The active region of the laser is contained within or along a lower surface of the first waveguiding layer, as in standard devices. The regrowth interface is located along a top surface of the first cladding layer, as compared to the prior art where this interface is located within the first waveguiding layer. The resulting configuration exhibits an improved coupling efficiency by maintaining the propagating optical mode within the active waveguiding layer and away from the regrowth interface.

Abstract: A laser device with one or more active regions, such as quantum wells, gain/lighting media, or other devices, and one or more non-absorbing regions, may be formed by a first growth run (growing a first semiconductor layer), then performing selective, shallow-depth etching, and then a second growth run (growing a second semiconductor layer). The laser device may include a first portion, one or more active regions located on the first portion, and a second portion located on the active region(s). A third portion may be located on one or more ends of the first portion and on the second portion. The third portion may be formed during the second growth run, after the etching step. The non-absorbing region(s) may be formed by the third portion and the end(s) of the first portion. If desired, the non-absorbing region(s) may be produced without annealing or locally-induced quantum well intermixing.

Abstract: A laser device with one or more active regions, such as quantum wells, gain/lighting media, or other devices, and one or more non-absorbing regions, may be formed by a first growth run (growing a first semiconductor layer), then performing selective, shallow-depth etching, and then a second growth run (growing a second semiconductor layer). The laser device may include a first portion, one or more active regions located on the first portion, and a second portion located on the active region(s). A third portion may be located on one or more ends of the first portion and on the second portion. The third portion may be formed during the second growth run, after the etching step. The non-absorbing region(s) may be formed by the third portion and the end(s) of the first portion. If desired, the non-absorbing region(s) may be produced without annealing or locally-induced quantum well intermixing.

Abstract: A laser device with one or more active regions, such as quantum wells, gain/lighting media, or other devices, and one or more non-absorbing regions, may be formed by a first growth run (growing a first semiconductor layer), then performing selective, shallow-depth etching, and then a second growth run (growing a second semiconductor layer). The laser device may include a first portion, one or more active regions located on the first portion, and a second portion located on the active region(s). A third portion may be located on one or more ends of the first portion and on the second portion. The third portion may be formed during the second growth run, after the etching step. The non-absorbing region(s) may be formed by the third portion and the end(s) of the first portion. If desired, the non-absorbing region(s) may be produced without annealing or locally-induced quantum well intermixing.

Abstract: A laser source includes a laser beam generating section for generating a laser beam in a cavity between first reflector and a second reflector; and a tap section provided in the cavity to take out a part of the laser beam. The laser source is a waveguide-based laser source.

Abstract: A high power laser source comprises a bar of laser diodes having a first coefficient of thermal expansion CTEbar on a submount having a second coefficient CTEsub and a cooler having a third coefficient CTEcool. The submount/cooler assembly shows an effective fourth coefficient CTEeff differing from CTEbar. This difference leads to a deformation of the crystal lattice of the lasers' active regions by mechanical stress. CTEeff is selected to be either lower than both CTEbar and CTEcool or is selected to be between CTEbar and CTEcool. The submount may either comprise layers of materials having different CTEs, e.g., a Cu layer of 10-40 ?m thickness and a Mo layer of 100-400 ?m thickness, or a single material with a varying CTEsub. Both result in a CTEsub varying across the submount's thickness.

Abstract: A high power laser source comprises a bar of laser diodes having a first coefficient of thermal expansion CTEbar on a submount having a second coefficient CTEsub and a cooler having a third coefficient CTEcool. The submount/cooler assembly shows an effective fourth coefficient CTEeff differing from CTEbar. This difference leads to a deformation of the crystal lattice of the lasers' active regions by mechanical stress. CTEeff is selected to be either lower than both CTEbar and CTEcool or is selected to be between CTEbar and CTEcool. The submount may either comprise layers of materials having different CTEs, e.g., a Cu layer of 10-40 ?m thickness and a Mo layer of 100-400 ?m thickness, or a single material with a varying CTEsub. Both result in a CTEsub varying across the submount's thickness.

Abstract: A high power laser source comprises at least a bar of laser diodes with a first coefficient of thermal expansion (CTEbar), a submount onto which said laser bar is affixed with a second coefficient of thermal expansion (CTEsub), and a cooler onto which said submount is affixed with a third coefficient of thermal expansion (CTEcool). The submount/cooling assembly exhibits an effective fourth coefficient of expansion (CTEeff). According to the invention, mechanical stress exerted to the laser bar improves reliability and optical performance. To effect this, CTEeff must differ from CTEbar, CTEeff?CTEbar. Preferably, CTEeff should differ by a predetermined amount from CTEbar. The difference is achieved in two ways: either by selecting CTEsub>CTEbar and CTEsub?CTEcool, or by selecting CTEsub<CTEbar and CTEsub<CTEcool. Thereby, all coefficients must be selected such that CTEeff differs from CTEbar: CTEeff?CTEbar, preferably by a percentage of 5% or by a predetermined amount of +/?3-4×10?7K?1.

Abstract: A laser source includes a laser beam generating section for generating a laser beam in a cavity between first reflector and a second reflector; and a tap section provided in the cavity to take out a part of the laser beam. The laser source is a waveguide-based laser source.

Abstract: A multi-chip hybrid-mounted device is provided that is fabricated by an extremely simple fabrication process, thereby enabling excellent reliability and yield. During the mounting process, the submount is kept at a bias temperature slightly below the solder melting point. For each chip to be mounted, an auxiliary heater element located adjacent to the actual mounting/soldering position is temporarily energized. Using a bias temperature, a local temperature increase of only a few degrees Celsius in the mounting/soldering area will initiate the soldering process and affix the chip. Such a small temperature increase is readily achieved by the laterally displaced heater element with only a minimal amount of thermal stress. The fabrication process is fully scalable and enables mounting of an arbitrarily large number of chips using only a single solder material.