Abstract: Modification of the topology of selected regions of individual VCSEL devices during fabrication is utilized to provide an array output beam with specific characteristics (e.g., “uniform” output power across the array). These physical features include at least the width of the metal aperture, the width of the oxide aperture, and/or the geometry of the contact ring structure on the top of the VCSEL device. The modifications may also function to adjust the numerical apertures (NAs) of the devices, the beam waist, wallplug efficiency, and the like.

Abstract: An array layout of VCSELs is intentionally mis-aligned with respect to the xy-plane of the device structure as defined by the crystallographic axes of the semiconductor material. The mis-alignment may take the form of skewing the emitter array with respect to the xy-plane, or rotating the emitter array. In either case, the layout pattern retains the desired, row/column structure (necessary for dicing the structure into one-dimensional arrays) while reducing the probability that an extended defect along a crystallographic plane will impact a large number of individual emitters.

Abstract: Modification of the topology of selected regions of individual VCSEL devices during fabrication is utilized to provide an array output beam with specific characteristics (e.g., “uniform” output power across the array). These physical features include the width of the metal aperture, the width of the modal filter, and/or the geometry of the contact ring structure on the top of the VCSEL device. The modifications may also function to adjust the numerical apertures (NAs) of the devices, the beam waist, wallplug efficiency, and the like.

Abstract: Modification of the topology of selected regions of individual VCSEL devices during fabrication is utilized to provide an array output beam with specific characteristics (e.g., “uniform” output power across the array). These physical features include the width of the metal aperture, the width of the modal filter, and/or the geometry of the contact ring structure on the top of the VCSEL device. The modifications may also function to adjust the numerical apertures (NAs) of the devices, the beam waist, wallplug efficiency, and the like.

Abstract: 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.

Abstract: 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.

Abstract: An array layout of VCSELs is intentionally mis-aligned with respect to the xy-plane of the device structure as defined by the crystallographic axes of the semiconductor material. The mis-alignment may take the form of skewing the emitter array with respect to the xy-plane, or rotating the emitter array. In either case, the layout pattern retains the desired, row/column structure (necessary for dicing the structure into one-dimensional arrays) while reducing the probability that an extended defect along a crystallographic plane will impact a large number of individual emitters.

Abstract: A densely-spaced single-emitter laser diode configuration is created by using a laser bar (or similar array configuration) attached to a submount component of a size sufficient to adequately support the enter laser structure. The surface of the submount component upon which the laser structure is attached is metallized and used to form the individual electrical contacts to the laser diodes within the integrated laser structure. Once attached to each other, the laser structure is singulated by creating vertical separations between adjacent light emission areas. The submount metallization is similarly segmented, creating separate electrodes that are used to individually energize their associated laser diodes.

Abstract: A composite substrate includes a submount substrate of an alternating pattern of electrically insulative portions, pieces, layers or segments and electrically conductive portions, pieces, layers or segments, and a shaft, back or plate for supporting the alternating pattern of electrically insulative portions and electrically conductive portions. An active device having a P-N junction can be mounted on the submount substrate. The electrically insulative portions, pieces, layers or segments can be formed from diamond while the electrically conductive portions, pieces, layers or segments can be formed from a metal or metal alloy.

Abstract: A broad area laser diode is configured to include an anti-guiding layer located outside of the active region of the device. The anti-guiding layer is formed of a high refractive index material that serves to de-couple unwanted, higher-order lateral modes (attributed to thermal lensing problems) from the lower-order mode output beam of output signal from the laser diode. The anti-guiding layer is formed using a single epitaxial growth step either prior to or subsequent to the steps used to grow the epitaxial layers forming the laser diode itself, thus creating a structure that provides suppression of unwanted higher-order modes without requiring a modification of specific process steps used to fabricate the laser diode itself.

Abstract: A broad area laser diode is configured to include an anti-guiding layer located outside of the active region of the device. The anti-guiding layer is formed of a high refractive index material that serves to de-couple unwanted, higher-order lateral modes (attributed to thermal lensing problems) from the lower-order mode output beam of output signal from the laser diode. The anti-guiding layer is formed using a single epitaxial growth step either prior to or subsequent to the steps used to grow the epitaxial layers forming the laser diode itself, thus creating a structure that provides suppression of unwanted higher-order modes without requiring a modification of specific process steps used to fabricate the laser diode itself.

Abstract: A densely-spaced single-emitter laser diode configuration is created, by using a laser bar (or similar array configuration) attached to a submount component of a size sufficient to adequately support the enter laser structure. The surface of the submount component upon which the laser structure is attached is metallized and used to form the individual electrical contacts to the laser diodes within the integrated laser structure. Once attached to each other, the laser structure is singulated by creating vertical separations between adjacent light emission areas. The submount metallization is similarly segmented, creating separate electrodes that are used to individually energize their associated laser diodes.

Abstract: A composite substrate includes a submount substrate of an alternating pattern of electrically insulative portions, pieces, layers or segments and electrically conductive portions, pieces, layers or segments, and a shaft, back or plate for supporting the alternating pattern of electrically insulative portions and electrically conductive portions. An active device having a P—N junction can be mounted on the submount substrate. The electrically insulative portions, pieces, layers or segments can be formed from diamond while the electrically conductive portions, pieces, layers or segments can be formed from a metal or metal alloy.

Abstract: A semiconductor laser diode comprises a semiconductor body having an n-region and a p-region laterally spaced apart within the semiconductor body. The laser diode is provided with an active region between the n-region and the p-region having a front end and a back end section, an n-metallization layer located adjacent the n-region and having a first injector for injecting current into the active region, and a p-metallization layer opposite to the n-metallization layer and adjacent the p-region and having a second injector for injecting current into the active region. The thickness and/or width of at least one metallization layer is chosen so as to control the current injection in a part of the active region near at least one end of the active region compared to the current injection in another part of the active region. The width of the at least one metallization layer is larger than a width of the active region.

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 semiconductor laser diode comprises a semiconductor body having an n-region and a p-region laterally spaced apart within the semiconductor body. The laser diode is provided with an active region between the n-region and the p-region having a front end and a back end section, an n-metallisation layer located adjacent the n-region and having a first injector for injecting current into the active region, and a p-metallisation layer opposite to the n-metallisation layer and adjacent the p-region and having a second injector for injecting current into the active region. The thickness and/or width of at least one metallisation layer is chosen so as to control the current injection in a part of the active region near at least one end of the active region compared to the current injection in another part of the active region. The width of the at least one metallisation layer is larger than a width of the active region.

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 high power laser source comprises a bar of laser diodes, a submount onto which said laser bar is affixed, and a cooler onto which said submount is affixed. The laser bar has a first coefficient of thermal expansion (CTEbar), the submount has a second coefficient of thermal expansion (CTEsub), and the cooler has a third coefficient of thermal expansion (CTEcool) the third coefficient (CTEcool) being higher than both said first coefficient (CTEbar) and said second coefficient (CTEsub). Contrary to the usual approach with a CTEsub matching the CTEbar, the second coefficient (CTEsub) is selected lower than both said first coefficient (CTEbar) and said third coefficient (CTEcool) according to the invention. A preferred range is CTEsub=k*CTEbar, with 0.4<k<0.9. The submount may consist of or comprise two or more layers of different materials having different CTEs, e.g.

Abstract: The invention relates to high power semiconductor diode lasers of the type commonly used in opto-electronics, mostly as so-called pump lasers for fiber amplifiers in the field of optical communication, e.g. for an erbium-doped fiber amplifier (EDFA) or a Raman amplifier. Such a laser, having a single cavity and working in single transverse mode, is improved by placing a multilayer large optical superlattice structure (LOSL) into at least one of the provided cladding layers. This LOSL provides for a significantly improved shape of the exit beam allowing an efficient high power coupling into the fiber of an opto-electronic network.