Abstract: A concentrically leaded power semiconductor package includes two or more generally concentric conductors. An inner conductor may provide an attachment point for one or more semiconductor devices at an end of the inner conductor and an electrical connection at an opposite end. An outer conductor may be pressed onto the inner conductor and may be separated by an electrical insulator. A semiconductor device, such as a light emitting diode (LED), may be attached to the inner conductor by epoxy gluing or by soldering, and may be attached to the outer conductor by a bonding wire. The package may be cylindrical or a rectangular solid. The package may incorporate additional semiconductor mounting surfaces and more than two conductors.

Abstract: A smoothing structure containing indium is formed between the substrate and the active region of a III-nitride light emitting device to improve the surface characteristics of the device layers. In some embodiments, the smoothing structure is a single layer, separated from the active region by a spacer layer which typically does not contain indium. The smoothing layer contains a composition of indium lower than the active region, and is typically deposited at a higher temperature than the active region. The spacer layer is typically deposited while reducing the temperature in the reactor from the smoothing layer deposition temperature to the active region deposition temperature. In other embodiments, a graded smoothing region is used to improve the surface characteristics. The smoothing region may have a graded composition, graded dopant concentration, or both.

Abstract: The present invention is an inverted III-nitride light-emitting device (LED) with enhanced total light generating capability. A large area device has an n-electrode that interposes the p-electrode metallization to provide low series resistance. The p-electrode metallization is opaque, highly reflective, and provides excellent current spreading. The p-electrode at the peak emission wavelength of the LED active region absorbs less than 25% of incident light per pass. A submount may be used to provide electrical and thermal connection between the LED die and the package. The submount material may be Si to provide electronic functionality such as voltage-compliance limiting operation. The entire device, including the LED-submount interface, is designed for low thermal resistance to allow for high current density operation. Finally, the device may include a high-refractive-index (n>1.8) superstrate.

Abstract: The present invention is an inverted III-nitride light-emitting device (LED)) with enhanced total light generating capability. A large area device has an n-electrode that interposes the p-electrode metallization to provide low series resistance. The p-electrode metallization is opaque, highly reflective, and provides excellent current spreading. The p-electrode at the peak emission wavelength of the LED active region absorbs less than 25% of incident light per pass. A submount may be used to provide electrical and thermal connection between the LED die and the package. The submount material may be Si to provide electronic functionality such as voltage-compliance limiting operation. The entire device, including the LED-submount interface, is designed for low thermal resistance to allow for high current density operation. Finally, the device may include a high-refractive-index (n>1.8) superstrate.

Abstract: An LED and a method of fabricating the LED which utilize controlled oxygen (O) doping to form at least one layer of the LED having an O dopant concentration which is correlated to the dominant emission wavelength of the LED. The O dopant concentration is regulated to be higher when the LED has been configured to have a longer dominant emission wavelength. Since the dominant emission wavelength is dependent on the composition of the active layer(s) of the LED, the O dopant concentration in the layer is related to the composition of the active layer(s). The controlled O doping improves the reliability while minimizing any light output penalty due to the introduction of O dopants. In an exemplary embodiment, the LED is an AlGaInP LED that includes a substrate, an optional distributed Bragg reflector layer, an n-type confining layer, an optional n-type set-back layer, an active region, an optional p-type set-back layer, a p-type confining layer and an optional window layer.

Abstract: In accordance with the invention, a difference in index of refraction is created at the mesa wall of a III-nitride flip chip light emitting device. The step in index of refraction reflects much of the light incident on the mesa wall back into the device where it can be usefully extracted. In some embodiments, a solder wall on the submount or a high index gel coating the light emitting device and the submount creates a sealed gap between the light emitting device and the submount. The gap is filled with a material having a low index of refraction. In other embodiments, a high index material covers the substrate of the light emitting device, and a low index material fills the gap between the submount and the light emitting device.

Abstract: A semiconductor device is provided having n-type device layers of III-V nitride having donor dopants such as germanium (Ge), silicon (Si), tin (Sn), and/or oxygen (O) and/or p-type device layers of III-V nitride having acceptor dopants such as magnesium (Mg), beryllium (Be), zinc (Zn), and/or cadmium (Cd), either simultaneously or in a doping superlattice, to engineer strain, improve conductivity, and provide longer wavelength light emission.

Abstract: Light emitting devices having a vertical optical path, e.g. a vertical cavity surface emitting laser or a resonant cavity light emitting or detecting device, having high quality mirrors may be achieved using wafer bonding or metallic soldering techniques. The light emitting region interposes one or two reflector stacks containing dielectric distributed Bragg reflectors (DBRs). The dielectric DBRs may be deposited or attached to the light emitting device. A host substrate of GaP, GaAs, InP, or Si is attached to one of the dielectric DBRs. Electrical contacts are added to the light emitting device.

Abstract: A method of fabricating a light emitting device includes providing a light emitting diode that emits primary light, and locating proximate to the light emitting diode a (Sr1−u−v−xMguCavBax)(Ga2−y−zAlyInzS4):Eu2+ phosphor material capable of absorbing at least a portion of the primary light and emitting secondary light having a wavelength longer than a wavelength of the primary light. The composition of the phosphor material can be selected to determine the wavelengths of the secondary light. In one embodiment, the light emitting device includes the phosphor material dispersed as phosphor particles in another material disposed around the light emitting diode. In another embodiment, the light emitting device includes the phosphor material deposited as a phosphor film on at least one surface of the light emitting diode.

Abstract: The invention is an outdoor lighting display using light emitting devices. A flexible light track is secured at the bottom of a channel, e.g. a letter or symbol. A top corresponding to the shape of the channel covers the channel to protect the flexible light track from weather changes. The flexible light track includes a plurality of plastic modules having electrical connectors and respective tracks. Light emitting devices (LEDs) are inserted in the plastic modules. Electrical wires are positioned in the tracks of the plastic modules such that the LEDs are electrically connected in parallel.

Abstract: A light emitting device and a method of fabricating the device utilize a supplementary fluorescent material that radiates secondary light in the red spectral region of the visible light spectrum to increase the red color component of the composite output light. The secondary light from the supplementary fluorescent material allows the device to produce “white” output light that is well-balanced with respect to color for true color rendering applications. The supplementary fluorescent material is included in a fluorescent layer that is positioned between a die and a lens of the device. The die is preferably a GaN based die that emits light having a peak wavelength of 470 nm. The fluorescent layer also includes a main fluorescent material. Preferably, the main fluorescent material is Cerium (Ce) activated and Gadolinium (Gd) doped Yttrium Aluminum Garnet (YAG) phosphor (“Ce:YAG phosphor”).

Abstract: A laser diode that is constructed in a trench in a manner such that the material in the trench acts as a waveguide. The laser diode includes a first contact layer constructed from a first semiconducting material of a first carrier type, the first semiconducting material having a first index of refraction. The first contact layer has a trench therein. The trench has a layer of a second semiconducting material of the first carrier type on the bottom surface. The index of refraction of the second semiconducting material is at least one percent greater than the index of refraction of the first semiconducting material. The laser also includes a first dielectric layer covering the first layer in those regions outside of the trench and a first cladding layer constructed from a third semiconducting material of the first carrier type. The first cladding layer overlies the dielectric layer. An active layer overlies the first cladding layer.

Abstract: The invention is a method for designing semiconductor light emitting devices such that the side surfaces (surfaces not parallel to the epitaxial layers) are formed at preferred angles relative to vertical (normal to the plane of the light-emitting active layer) to improve light extraction efficiency and increase total light output efficiency. Device designs are chosen to improve efficiency without resorting to excessive active area-yield loss due to shaping. As such, these designs are suitable for low-cost, high-volume manufacturing of semiconductor light-emitting devices with improved characteristics.

Abstract: Light emitting devices having a vertical optical path, e.g. a vertical cavity surface emitting laser or a resonant cavity light emitting or detecting device, having high quality mirrors may be achieved using wafer bonding or metallic soldering techniques. The light emitting region interposes one or two reflector stacks containing dielectric distributed Bragg reflectors (DBRs). The dielectric DBRs may be deposited or attached to the light emitting device. A host substrate of GaP, GaAs, InP, or Si is attached to one of the dielectric DBRs. Electrical contacts are added to the light emitting device.

Abstract: A light emitting device includes a heterojunction having a p-type layer and an n-type layer. The n-electrode is electrically connected to the n-type layer while the p-electrode is electrically connected to the p-type layer. The p and n-electrodes are positioned to form a region having uniform light intensity.

Abstract: A method of forming a light-transmissive contact on a p-type Gallium nitride (GaN) layer of an optoelectronic device includes in one embodiment, introducing a selected metal in an oxidized condition, rather than oxidizing the metal only after it has been deposited on the surface of the p-type GaN layer. In some applications, the oxidized metal provides sufficient lateral conductivity to eliminate the conventional requirement of a second highly conductive contact metal, such as gold. If the second contact metal is desired, an anneal in an oxygen-free environment is performed after deposition of the second layer. The anneal causes the second metal to penetrate the oxidized metal and to fuse to the surface of the p-type GaN layer. In a second embodiment, the oxidation occurs only after at least one of the two metals is deposited on the surface of the p-type GaN layer.

Abstract: Light emitting devices having a vertical optical path, e.g. a vertical cavity surface emitting laser or a resonant cavity light emitting or detecting device, having high quality mirrors may be achieved using wafer bonding or metallic soldering techniques. The light emitting region interposes one or two reflector stacks containing dielectric distributed Bragg reflectors (DBRs). The dielectric DBRs may be deposited or attached to the light emitting device. A host substrate of GaP, GaAs, InP, or Si is attached to one of the dielectric DBRs. Electrical contacts are added to the light emitting device.

Abstract: In the present invention, an interfacial layer is added to a light-emitting diode or laser diode structure to perform the role of strain engineering and impurity gettering. A layer of GaN or AlxInyGa1−x−yN (0≦x≦1, 0≦y≦1) doped with Mg, Zn, Cd can be used for this layer. Alternatively, when using AlxInyGa1−x−yN (x>0), the layer may be undoped. The interfacial layer is deposited directly on top of the buffer layer prior to the growth of the n-type (GaN:Si) layer and the remainder of the device structure. The thickness of the interface layer varies from 0.01-10.0 &mgr;m.

Abstract: An LED package includes a heat-sinking slug that is inserted into an insert-molded leadframe. The slug may include an optional reflector cup. Within this cup, the LED and a thermally conducting sub-mount may be attached. Wire bonds extend from the LEDs to metal leads. The metal leads are electrically and thermally isolated from the slug. An optical lens may be added by mounting a pre-molded thermoplastic lens and a soft encapsulant or by casting epoxy to cover the LED or by a cast epoxy lens over a soft encapsulant.

Abstract: A device with a low resistance zone having confinement, superior reproducibility, and a very high yield comprises a plurality of semiconductor layers, wherein layer resistivity is changed by annealing. The semiconductor layers include a resistance zone having a high activation coefficient of acceptor impurities and a resistance region having a low activation coefficient of acceptor impurities. The activation coefficient is controlled by irradiation with laser light. In addition, laser light is irradiated and absorbed into the semiconductor layers in one part of, or the entire, semiconductor layers, such that layer resistivity in the irradiated regions is changed by annealing resulting from such irradiation.