Abstract: A light emitting device is produced by depositing a layer of wavelength converting material over the light emitting device, testing the device to determine the wavelength spectrum produced and correcting the wavelength converting member to produce the desired wavelength spectrum. The wavelength converting member may be corrected by reducing or increasing the amount of wavelength converting material. In one embodiment, the amount of wavelength converting material in the wavelength converting member is reduced, e.g., through laser ablation or etching, to produce the desired wavelength spectrum.

Abstract: A photonic crystal structure is formed in an n-type region of a III-nitride semiconductor structure including an active region sandwiched between an n-type region and a p-type region. A reflector is formed on a surface of the p-type region opposite the active region. In some embodiments, the growth substrate on which the n-type region, active region, and p-type region are grown is removed, in order to facilitate forming the photonic crystal in an n-type region of the device, and to facilitate forming the reflector on a surface of the p-type region underlying the photonic crystal. The photonic crystal and reflector form a resonant cavity, which may allow control of light emitted by the active region.

Abstract: LED epitaxial layers (n-type, p-type, and active layers) are grown on a substrate. For each die, the n and p layers are electrically bonded to a package substrate that extends beyond the boundaries of the LED die such that the LED layers are between the package substrate and the growth substrate. The package substrate provides electrical contacts and conductors leading to solderable package connections. The growth substrate is then removed. Because the delicate LED layers were bonded to the package substrate while attached to the growth substrate, no intermediate support substrate for the LED layers is needed. The relatively thick LED epitaxial layer that was adjacent the removed growth substrate is then thinned and its top surface processed to incorporate light extraction features.

Abstract: Low profile, side-emitting LEDs are described that generate white light, where all light is emitted within a relatively narrow angle generally parallel to the surface of the light-generating active layer. The LEDs enable the creation of very thin backlights for backlighting an LCD. In one embodiment, the LED emits blue light and is a flip chip with the n and p electrodes on the same side of the LED. Separately from the LED, a transparent wafer has deposited on it a red and green phosphor layer. The phosphor color temperature emission is tested, and the color temperatures vs. positions along the wafer are mapped. A reflector is formed over the transparent wafer. The transparent wafer is singulated, and the phosphor/window dice are matched with the blue LEDs to achieve a target white light color temperature. The phosphor/window is then affixed to the LED.

Abstract: A light emitting device is produced by depositing a layer of wavelength converting material over the light emitting device, testing the device to determine the wavelength spectrum produced and correcting the wavelength converting member to produce the desired wavelength spectrum. The wavelength converting member may be corrected by reducing or increasing the amount of wavelength converting material. In one embodiment, the amount of wavelength converting material in the wavelength converting member is reduced, e.g., through laser ablation or etching, to produce the desired wavelength spectrum.

Abstract: A photonic crystal structure is formed in an n-type region of a III-nitride semiconductor structure including an active region sandwiched between an n-type region and a p-type region. A reflector is formed on a surface of the p-type region opposite the active region. In some embodiments, the growth substrate on which the n-type region, active region, and p-type region are grown is removed, in order to facilitate forming the photonic crystal in an an-type region of the device, and to facilitate forming the reflector on a surface of the p-type region underlying the photonic crystal. The photonic crystal and reflector form a resonant cavity, which may allow control of light emitted by the active region.

Abstract: In one embodiment, an AlInGaP LED includes a bottom n-type layer, an active layer, a top p-type layer, and a thick n-type GaP layer over the top p-type layer. The thick n-type GaP layer is then subjected to an electrochemical etch process that causes the n-type GaP layer to become porous and light-diffusing. Electrical contact is made to the p-GaP layer under the porous n-GaP layer by providing metal-filled vias through the porous layer, or electrical contact is made through non-porous regions of the GaP layer between porous regions. The LED chip may be mounted on a submount with the porous n-GaP layer facing the submount surface. The pores and metal layer reflect and diffuse the light, which greatly increases the light output of the LED. Other embodiments of the LED structure are described.

Abstract: A light emitting device includes a semiconductor structure having a light emitting layer disposed between an n-type region and a p-type region. A porous region is disposed between the light emitting layer and a contact electrically connected to one of the n-type region and the p-type region. The porous region scatters light away from the absorbing contact, which may improve light extraction from the device. In some embodiments the porous region is an n-type semiconductor material such as GaN or GaP.

Abstract: Low profile, side-emitting LEDs are described, where all light is efficiently emitted within a relatively narrow angle generally parallel to the surface of the light-generating active layer. The LEDs enable the creation of very thin backlights for backlighting an LCD. In one embodiment, the LED is a flip chip with the n and p electrodes on the same side of the LED, and the LED is mounted electrode-side down on a submount. A reflector is provided on the top surface of the LED so that light impinging on the reflector is reflected back toward the active layer and eventually exits through a side surface of the LED. A waveguide layer and/or one or more phosphors layers are deposed between the semiconductor layers and the reflector for increasing the side emission area for increased efficiency. Side-emitting LEDs with a thickness of between 0.2-0.4 mm can be created.

Abstract: A semiconductor light emitting device includes an n-type region, a p-type region, and light emitting region disposed between the n- and p-type regions. The n-type, p-type, and light emitting regions form a cavity having a top surface and a bottom surface. Both the top surface and the bottom surface of the cavity may have a rough surface. For example, the surface may have a plurality of peaks separated by a plurality of valleys. In some embodiments, the thickness of the cavity is kept constant by incorporating an etch-stop layer into the device, then thinning the layers of the device by a process that terminates on the etch-stop layer.

Abstract: A multi-frequency light source is disclosed. In one aspect, a multi-frequency light source may comprise a gain region defined by a first and second mirror. The gain region may have a resonant mode. The light source may also have an external cavity defined by a third mirror and the second mirror. The external cavity has plurality of resonant modes, including a plurality of contiguous desired modes of operation. The second mirror may be formed such that the multi-frequency light source operates at the desired modes of the external cavity.

Abstract: A multi-frequency light source is disclosed. In one disclosed aspect, the light source may comprise a gain region defined by a first and second mirror. The gain region may have corresponding resonant modes. An external cavity defined by a third mirror and said second mirror is also provided, with the external cavity having a plurality of resonant modes. The second mirror may be terminated with a layer of high reflectivity. In a further aspect, the second mirror may be terminated with an antiphase layer.

Abstract: In situ removal of selected or patterned portions of semiconductor layers is accomplished by induced evaporation enhancement to form reversed bias current confinement structures in semiconductor devices, such as heterostructure lasers and array lasers.

Abstract: The technique of induced evaporation enhancement is used in MOCVD to accomplish geometrical variations via atomic level removal or thinning or negative growth techniques in situ during or after epitaxial growth thereby varying optical and electrical properties of fabricated semiconductor structures during growth. Among the structures capable of being fabricated are three dimensional buried heterostructures, transparent window lasers, multiple wavelength array lasers, index guided and antiguided mechanisms and transparent optical waveguide structures for optical signal coupling in integrated circuitry.

Abstract: In situ removal of selected or patterned portions of quantum well layers is accomplished by photo induced evaporation enhancement to form quantum wire, patterned quantum wire and multiple quantum wires in a semiconductor structure.

Abstract: In situ removal of selected or patterned portions of quantum well layers is accomplished by photo induced evaporation enhancement to form quantum wire, patterned quantum wire and multiple quantum wires in a semiconductor structure.

Abstract: A quantum wire in a groove in a semiconductor layer emits coherent light in a semiconductor laser structure. Linear array, vertical array and two-dimensional array multiple quantum wire semiconductor laser structures are also embodiments of the quantum wire in a semiconductor layer groove. Optical waveguides and reverse bias junctions can also be formed with the quantum wire semiconductor laser structures.

Abstract: In situ removal of selected or patterned portions of quantum well layers is accomplished by photo induced evaporation enhancement to form quantum wire and multiple quantum wires in a semiconductor laser structure.

Abstract: In situ removal of selected or patterned portions of semiconductor layers is accomplished by induced evaporation enhancement to form patterned buried impurity layers in semiconductor devices, such as heterostructure lasers and array lasers, which function as buried impurity induced layer disordering (BIILD) sources upon subsequent annealing. These layers may be formed to either function as buried impurity induced layer disordering (BIILD) sources or function as a reverse bias junction configuration of confining current to the active region of a laser structure. Their discussion here is limited to the first mentioned function.

Abstract: In situ geometrical and stoichiometric properties of deposited films are brought about by employing a scanned irradiation source directed to a spot which is scanned across the growth surface in a chemical vaGOVERNMENT RIGHTSThe Government has certain rights in this invention pursuant to Contract No. 86F173100 awarded by the Defense Advanced Research Projects Agency (DARPA).