Patent application number | Description | Published |
20090034571 | MIGRATION ENHANCED EPITAXY FABRICATION OF ACTIVE REGIONS HAVING QUANTUM WELLS - Semiconductor lasers, such as VCSELs having active regions with flattening layers associated with nitrogen-containing quantum wells are disclosed. MEE (Migration Enhanced Epitaxy) is used to form a flattening layer upon which a quantum well is formed and thereby enhance smoothness of quantum well interfaces and to achieve narrowing of the spectrum of light emitted from nitrogen containing quantum wells. A cap layer is also formed over the quantum well. | 02-05-2009 |
20090161714 | OPTIMIZING VCSEL MIRRORS FOR IMPROVING TEMPERATURE RESPONSE - Improved slope efficiency in a VCSEL can be accomplished by selecting particular mirror layer compositions and/or mirror layer configurations that minimize increased reflectivity in the top mirror and/or maximize increased reflectivity of the bottom mirror with increasing temperature. Improved reflectivity of the bottom mirror compared to the top mirror over a desired operating temperature range can be facilitated by (i) selecting mirror pairs for the bottom and/or top mirror that gives the bottom mirror pairs a greater increase in contrast ratio with increasing temperature compared to the top-mirror pairs, and/or (ii) including fewer mirror pairs in the bottom mirror than the number of mirror pairs that would give optimal reflectivity. | 06-25-2009 |
20110045621 | VERTICAL CAVITY SURFACE EMITTING LASER HAVING MULTIPLE TOP-SIDE CONTACTS - A VCSEL with undoped mirrors. An essentially undoped bottom DBR mirror is formed on a substrate. A periodically doped first conduction layer region is formed on the bottom DBR mirror. The first conduction layer region is heavily doped at a location where the optical electric field is at about a minimum. An active layer, including quantum wells, is on the first conduction layer region. A periodically doped second conduction layer region is connected to the active layer. The second conduction layer region is heavily doped where the optical electric field is at a minimum. An aperture is formed in the epitaxial structure above the quantum wells. A top mirror coupled to the periodically doped second conduction layer region. The top mirror is essentially undoped and formed in a mesa structure. An oxide is formed around the mesa structure to protect the top mirror during wet oxidation processes. | 02-24-2011 |
20110086452 | SEMICONDUCTOR HAVING ENHANCED CARBON DOPING - Methods for fabricating semiconductors with enhanced strain. One embodiment includes fabrication of a semiconductor device with an epitaxial structure. The epitaxial structure is formed with one or more semiconductor layers. One or more of the layers includes a dopant including small quantities of Al and repeated delta doping during expitaxial growth to form periods where surfaces are group III rich. | 04-14-2011 |
20110090930 | VERTICAL CAVITY SURFACE EMITTING LASER WITH UNDOPED TOP MIRROR - A VCSEL with undoped top mirror. The VCSEL is formed from an epitaxial structure deposited on a substrate. A doped bottom mirror is formed on the substrate. An active layer that includes quantum wells is formed on the bottom mirror. A periodically doped conduction layer is formed on the active layer. The periodically doped conduction layer is heavily doped at locations where the optical energy is at a minimum when the VCSEL is in operation. A current aperture is used between the conduction layer and the active region. An undoped top mirror is formed on the heavily doped conduction layer. | 04-21-2011 |
20110096803 | ASYMMETRIC DBR PAIRS COMBINED WITH PERIODIC AND MODULATION DOPING TO MAXIMIZE CONDUCTION AND REFLECTIVITY, AND MINIMIZE ABSORPTION - An optical device for improving conduction and reflectivity and minimizing absorption. The optical device includes a first mirror comprising a first plurality of mirror periods designed to reflect an optical field at a predetermined wavelength, where the optical field has peaks and nulls. Each of the plurality of mirror periods includes a first layer of having a high carrier mobility, a second layer having lower carrier mobility, and a first compositional ramp between the first and second layers. The thicknesses of the first and second layers for at least a portion of the first plurality of mirror periods are established such that the nulls of the optical field occur within the first layer and not within the compositional ramp. At least the portion of the first layers within the first plurality of mirror periods include elevated doping concentrations at locations of the nulls of the optical field. | 04-28-2011 |
20110306156 | SURFACE GRATINGS ON VCSELS FOR POLARIZATION PINNING - Methods for manufacturing a polarization pinned vertical cavity surface emitting laser (VCSEL). Steps include growing a lower mirror on a substrate; growing an active region on the lower mirror; growing an upper mirror on the active region; depositing a grating layer on the upper minor; and etching a grating into the grating layer. | 12-15-2011 |
20120213243 | VERTICAL CAVITY SURFACE EMITTING LASER WITH UNDOPED TOP MIRROR - A VCSEL with undoped top mirror. The VCSEL is formed from an epitaxial structure deposited on a substrate, and a periodically doped conduction layer is coupled to the undoped top minor. A periodically doped spacer layer is coupled to an active region. An undoped bottom minor coupled to the periodically doped spacer layer. A first intracavity contact is coupled to the periodically doped conduction layer and a second intracavity contact is coupled to the periodically doped spacer layer. | 08-23-2012 |
20120236891 | LASERS WITH QUANTUM WELLS HAVING HIGH INDIUM AND LOW ALUMINUM WITH BARRIER LAYERS HAVING HIGH ALUMINUM AND LOW INDIUM WITH REDUCED TRAPS - A VCSEL can include: one or more quantum wells having (Al)InGaAs; two or more quantum well barriers having Al(In)GaAs bounding the one or more quantum well layers; and one or more transitional monolayers deposited between each quantum well layer and quantum well barrier, wherein the quantum wells, barriers and transitional monolayers are substantially devoid of traps. The one or more transitional monolayers include GaP, GaAs, and/or GaAsP. Alternatively, the VCSEL can include two or more transitional monolayers of AlInGaAs with a barrier-side monolayer having lower In and higher Al compared to a quantum well side monolayer that has higher In and lower Al. | 09-20-2012 |
20120236892 | LASERS WITH INGAAS(P) QUANTUM WELLS WITH INDIUM INGAP BARRIER LAYERS WITH REDUCED DECOMPOSITION - A method for preparing a VCSEL can use MBE for: growing a first conduction region over a first mirror region; growing an active region over the first conduction region opposite of the first mirror region, including: (a) growing a quantum well barrier having In | 09-20-2012 |
20120270346 | ASYMMETRIC DBR PAIRS COMBINED WITH PERIODIC AND MODULATION DOPING TO MAXIMIZE CONDUCTION AND REFLECTIVITY, AND MINIMIZE ABSORPTION - Methods for fabricating an optical device that exhibits improved conduction and reflectivity, and minimized absorption. Steps include forming a plurality of mirror periods designed to reflect an optical field having peaks and nulls. The formation of a portion of the plurality of minor periods includes forming a first layer having a thickness of less than one-quarter wavelength of the optical field; forming a first compositional ramp on the first layer; and forming a second layer on the compositional ramp, the second layer having a different index of refraction than the first layer and having a thickness such that the nulls of the optical field occur within the second layer and not within the compositional ramp, and wherein forming the second layer further comprises heavily doping the second layer at a location of the nulls of the optical field. | 10-25-2012 |
20140198817 | Lasers With InGaAsP Quantum Wells And GaAsP Barrier Layers - A laser can include an active region having: one or more quantum wells having InGaAsP; and two or more quantum well barriers having GaAsP bounding the one or more quantum wells, wherein the active region is devoid of Al. The laser emits light having about 850 nm. The one or more quantum wells can have a composition In | 07-17-2014 |
20140269802 | Lasers With GaPSb Barrier Layers - A laser active region can include a quantum well barrier having GaPSb. The active region can include one or more quantum wells, and a quantum well barrier having GaPSb bounding each side of each of the one or more quantum wells. The quantum well barrier can be GaP | 09-18-2014 |