| Patent application number | Description | Published |
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| 20080198881 | OPTIMIZATION OF LASER BAR ORIENTATION FOR NONPOLAR AND SEMIPOLAR (Ga,Al,In,B)N DIODE LASERS - Optical gain of a nonpolar or semipolar Group-III nitride diode laser is controlled by orienting an axis of light propagation in relation to an optical polarization direction or crystallographic orientation of the diode laser. The axis of light propagation is substantially perpendicular to the mirror facets of the diode laser, and the optical polarization direction is determined by the crystallographic orientation of the diode laser. To maximize optical gain, the axis of light propagation is oriented substantially perpendicular to the optical polarization direction or crystallographic orientation. | 08-21-2008 |
| 20080308907 | PLANAR NONPOLAR m-PLANE GROUP III NITRIDE FILMS GROWN ON MISCUT SUBSTRATES - A nonpolar III-nitride film grown on a miscut angle of a substrate, in order to suppress the surface undulations, is provided. The surface morphology of the film is improved with a miscut angle towards an a-axis direction comprising a 0.15° or greater miscut angle towards the a-axis direction and a less than 30° miscut angle towards the a-axis direction. | 12-18-2008 |
| 20090001519 | GROWTH OF PLANAR, NON-POLAR, GROUP-III NITRIDE FILMS - Growth methods for planar, non-polar, Group-III nitride films are described. The resulting films are suitable for subsequent device regrowth by a variety of growth techniques. | 01-01-2009 |
| 20090039356 | PLANAR NONPOLAR M-PLANE GROUP III-NITRIDE FILMS GROWN ON MISCUT SUBSTRATES - A nonpolar III-nitride film grown on a miscut angle of a substrate. The miscut angle towards the <000-1> direction is 0.75° or greater miscut and less than 27° miscut towards the <000-1> direction. Surface undulations are suppressed and may comprise faceted pyramids. A device fabricated using the film is also disclosed. A nonpolar III-nitride film having a smooth surface morphology fabricated using a method comprising selecting a miscut angle of a substrate upon which the nonpolar III-nitride films are grown in order to suppress surface undulations of the nonpolar III-nitride films. A nonpolar III-nitride-based device grown on a film having a smooth surface morphology grown on a miscut angle of a substrate which the nonpolar III-nitride films are grown. The miscut angle may also be selected to achieve long wavelength light emission from the nonpolar film. | 02-12-2009 |
| 20090072353 | METHOD FOR INCREASING THE AREA OF NON-POLAR AND SEMI-POLAR NITRIDE SUBSTRATES - A method for fabricating a high quality freestanding nonpolar and semipolar nitride substrate with increased surface area, comprising stacking multiple films by growing the films one on top of each other with different and non-orthogonal growth directions. | 03-19-2009 |
| 20090146170 | HIGH LIGHT EXTRACTION EFFICIENCY NITRIDE BASED LIGHT EMITTING DIODE BY SURFACE ROUGHENING - A III-nitride light emitting diode (LED) and method of fabricating the same, wherein at least one surface of a semipolar or nonpolar plane of a III-nitride layer of the LED is textured, thereby forming a textured surface in order to increase light extraction. The texturing may be performed by plasma assisted chemical etching, photolithography followed by etching, or nano-imprinting followed by etching. | 06-11-2009 |
| 20090194761 | ENHANCEMENT OF OPTICAL POLARIZATION OF NITRIDE LIGHT-EMITTING DIODES BY INCREASED INDIUM INCORPORATION - An increase in the Indium (In) content in light-emitting layers of light-emitting diode (LED) structures prepared on nonpolar III-nitride substrates result in higher polarization ratios for light emission than LED structures containing lesser In content. Polarization ratios should be higher than 0.7 at wavelengths longer than 470 nm. | 08-06-2009 |
| 20090250686 | METHOD FOR FABRICATION OF SEMIPOLAR (Al, In, Ga, B)N BASED LIGHT EMITTING DIODES - A yellow Light Emitting Diode (LED) with a peak emission wavelength in the range 560-580 nm is disclosed. The LED is grown on one or more III-nitride-based semipolar planes and an active layer of the LED is composed of indium (In) containing single or multi-quantum well structures. The LED quantum wells have a thickness in the range 2-7 nm. A multi-color LED or white LED comprised of at least one semipolar yellow LED is also disclosed. | 10-08-2009 |
| 20090294775 | HEXAGONAL WURTZITE TYPE EPITAXIAL LAYER POSSESSING A LOW ALKALI-METAL CONCENTRATION AND METHOD OF CREATING THE SAME - A method of obtaining a hexagonal würtzite type epitaxial layer with a low impurity concentration of alkali-metal by using a hexagonal würtzite substrate possessing a higher impurity concentration of alkali-metal, wherein a surface of the substrate upon which the epitaxial layer is grown has a crystal plane which is different from the c-plane. | 12-03-2009 |
| 20090310640 | MOCVD GROWTH TECHNIQUE FOR PLANAR SEMIPOLAR (Al, In, Ga, B)N BASED LIGHT EMITTING DIODES - A III-nitride optoelectronic device comprising a light emitting diode (LED) or laser diode with a peak emission wavelength longer than 500 nm. The III-nitride device has a dislocation density, originating from interfaces between an indium containing well layer and barrier layers, less than 9×10 | 12-17-2009 |
| 20090320745 | HEATER DEVICE AND METHOD FOR HIGH PRESSURE PROCESSING OF CRYSTALLINE MATERIALS - An improved heater for processing materials or growing crystals in supercritical fluids is provided. In a specific embodiment, the heater is scalable up to very large volumes and is cost effective. In conjunction with suitable high pressure apparatus, the heater is capable of processing materials at pressures and temperatures of 0.2-2 GPa and 400-1200° C., respectively. | 12-31-2009 |
| 20100052008 | ENHANCEMENT OF OPTICAL POLARIZATION OF NITRIDE LIGHT-EMITTING DIODES BY WAFER OFF-AXIS CUT - An off-axis cut of a nonpolar III-nitride wafer towards a polar (−c) orientation results in higher polarization ratios for light emission than wafers without such off-axis cuts. A 5° angle for an off-axis cut has been confirmed to provide the highest polarization ratio (0.9) than any other examined angles for off-axis cuts between 0 and 27°. | 03-04-2010 |
| 20100065854 | GROWTH AND MANUFACTURE OF REDUCED DISLOCATION DENSITY AND FREE-STANDING ALUMINUM NITRIDE FILMS BY HYDRIDE VAPOR PHASE EPITAXY - A Group III-nitride semiconductor film containing aluminum, and methods for growing this film. A film is grown by patterning a substrate, and growing the Group III-nitride semi-conductor film containing aluminum on the substrate at a temperature designed to increase the mobility of aluminum atoms to increase a lateral growth rate of the Group III-nitride semiconductor film. The film optionally includes a substrate patterned with elevated stripes separated by trench regions, wherein the stripes have a height chosen to allow the Group III-nitride semiconductor film to coalesce prior to growth from the bottom of the trenches reaching the top of the stripes, the temperature being greater than 1075° C., the Group III-nitride semiconductor film being grown using hydride vapor phase epitaxy, the stripes being oriented along a (1-100) direction of the substrate or the growing film, and a dislocation density of the grown film being less than 10 | 03-18-2010 |
| 20100075107 | HEXAGONAL WURTZITE SINGLE CRYSTAL AND HEXAGONAL WURTZITE SINGLE CRYSTAL SUBSTRATE - A technique for growing high quality bulk hexagonal single crystals using a solvo-thermal method, and a technique for achieving the high quality and high growth rate at the same time. The crystal quality strongly depends on the growth planes, wherein a nonpolar or semipolar seed surface such as {10-10}, {10-11}, {10-1-1}, {10-12}, {10-1-2}, {11-20}, {11-22}, {11-2-2} gives a higher crystal quality as compared to a c-plane seed surface such as (0001) and (000-1). Also, the growth rate strongly depends on the growth planes, wherein a semipolar seed surface such as {10-12}, {10-1-2}, {11-22}, {11-2-2} gives a higher growth rate. High crystal quality and high growth rate are achievable at the same time by choosing the suitable growth plane. The crystal quality also depends on the seed surface roughness, wherein high crystal quality is achievable when the nonpolar or semipolar seed surface RMS roughness is below 100 nm; on the other hand, the crystal grown from the Ga-face or N-face results in poor crystal quality, even though grown from an atomically smooth surface. | 03-25-2010 |
| 20100075175 | LARGE-AREA SEED FOR AMMONOTHERMAL GROWTH OF BULK GALLIUM NITRIDE AND METHOD OF MANUFACTURE - A high-quality, large-area seed crystal for ammonothermal GaN growth and method for fabricating. The seed crystal comprises double-side GaN growth on a large-area substrate. The seed crystal is of relatively low defect density and has flat surfaces free of bowing. The seed crystal is useful for producing large-volume, high-quality bulk GaN crystals by ammonothermal growth methods for eventual wafering into large-area GaN substrates for device fabrication. | 03-25-2010 |
| 20100090240 | PHOTOELECTROCHEMICAL ETCHING FOR CHIP SHAPING OF LIGHT EMITTING DIODES - A photoelectrochemical (PEC) etch is performed for chip shaping of a device comprised of a III-V semiconductor material, in order to extract light emitted into guided modes trapped in the III-V semiconductor material. The chip shaping involves varying an angle of incident light during the PEC etch to control an angle of the resulting sidewalls of the III-V semiconductor material. The sidewalls may be sloped as well as vertical, in order to scatter the guided modes out of the III-V semiconductor material rather than reflecting the guided modes back into the III-V semiconductor material. In addition to shaping the chip in order to extract light emitted into guided modes, the chip may be shaped to act as a lens, to focus its output light, or to direct its output light in a particular way. | 04-15-2010 |
| 20100108985 | OPTOELECTRONIC DEVICE BASED ON NON-POLAR AND SEMI-POLAR ALUMINUM INDIUM NITRIDE AND ALUMINUM INDIUM GALLIUM NITRIDE ALLOYS - A high-power and high-efficiency light emitting device with emission wavelength (λ | 05-06-2010 |
| 20100111808 | GROUP-III NITRIDE MONOCRYSTAL WITH IMPROVED CRYSTAL QUALITY GROWN ON AN ETCHED-BACK SEED CRYSTAL AND METHOD OF PRODUCING THE SAME - The present invention provides a method for growing group III-nitride crystals wherein the group III-nitride crystal growth occurs on an etched seed crystal. The etched seed is fabricated prior to growth using a temperature profile which produces a high solubility of the group III-nitride material in a seed crystals zone as compared to a source materials zone. The measured X-ray diffraction of the obtained crystals have significantly narrower Full Width at Half Maximum values as compared to crystals grown without etch back of the seed crystal surfaces prior to growth. | 05-06-2010 |
| 20100133663 | TECHNIQUE FOR THE GROWTH OF PLANAR SEMI-POLAR GALLIUM NITRIDE - A method for growing planar, semi-polar nitride film on a miscut spinel substrate, in which a large area of the planar, semi-polar nitride film is parallel to the substrate's surface. The planar films and substrates are: (1) {10 | 06-03-2010 |
| 20100148195 | METHOD FOR IMPROVED GROWTH OF SEMIPOLAR (AL,IN,GA,B)N - A method for improved growth of a semipolar (Al,In,Ga,B)N semiconductor thin film using an intentionally miscut substrate. Specifically, the method comprises intentionally miscutting a substrate, loading a substrate into a reactor, heating the substrate under a flow of nitrogen and/or hydrogen and/or ammonia, depositing an In | 06-17-2010 |
| 20100193911 | IN-SITU DEFECT REDUCTION TECHNIQUES FOR NONPOLAR AND SEMIPOLAR (Al, Ga, In)N - A method for growing reduced defect density planar gallium nitride (GaN) films is disclosed. The method includes the steps of (a) growing at least one silicon nitride (SiN | 08-05-2010 |
| 20100219416 | METHOD OF IMPROVING SURFACE MORPHOLOGY OF (GA,AL,IN,B)N THIN FILMS AND DEVICES GROWN ON NONPOLAR OR SEMIPOLAR (GA,AL,IN,B)N SUBSTRATES - A method for improving the growth morphology of (Ga,Al,In,B)N thin films on nonpolar or semipolar (Ga,Al,In,B)N substrates, wherein a (Ga,Al,In,B)N thin film is grown directly on a nonpolar or semipolar (Ga,Al,In,B)N substrate or template and a portion of the carrier gas used during growth is comprised of an inert gas. Nonpolar or semipolar nitride LEDs and diode lasers may be grown on the smooth (Ga,Al,In,B)N thin films grown by the present invention. | 09-02-2010 |
| 20100264461 | N-polar aluminum gallium nitride/gallium nitride enhancement-mode field effect transistor - A novel enhancement mode field effect transistor (FET), such as a High Electron Mobility Transistors (HEMT), has an N-polar surface uses polarization fields to reduce the electron population under the gate in the N-polar orientation, has improved dispersion suppression, and low gate leakage. | 10-21-2010 |
| 20100283078 | TRANSPARENT MIRRORLESS LIGHT EMITTING DIODE - An (Al, Ga, In)N light emitting diode (LED) in which multi-directional light can be extracted from one or more surfaces of the LED before entering a shaped optical element and subsequently being extracted to air. In particular, the (Al, Ga, In)N and transparent contact layers (such as ITO or ZnO) are embedded in or combined with a shaped optical element, which may be an epoxy, glass, silicon or other material molded into a sphere or inverted cone shape, wherein most of the light entering the inverted cone shape lies within a critical angle and is extracted. The present invention also minimizes internal reflections within the LED by eliminating mirrors and/or mirrored surfaces, in order to minimize re-absorption of the LED's light by the emitting layer (or the active layer) of the LED. To assist in minimizing internal reflections, transparent electrodes, such as ITO or ZnO, may be used. Surface roughening by patterning or anisotropically etching (i.e., creating microcones) may also assist in light extraction, as well as minimizing internal reflections. | 11-11-2010 |
| 20100295081 | SINGLE OR MULTI-COLOR HIGH EFFICIENCY LIGHT EMITTING DIODE (LED) BY GROWTH OVER A PATTERNED SUBSTRATE - A single or multi-color light emitting diode (LED) with high extraction efficiency is comprised of a substrate, a buffer layer formed on the substrate, one or more patterned layers deposited on top of the buffer layer, and one or more active layers formed on or between the patterned layers, for example by Lateral Epitaxial Overgrowth (LEO), and including one or more light emitting species, such as quantum wells. The patterned layers include a patterned, perforated or pierced mask made of insulating, semiconducting or metallic material, and materials filling holes in the mask. The patterned layer acts as an optical confining layer due to a contrast of a refractive index with the active layer and/or as a buried diffraction grating due to variation of a refractive index between the mask and the material filling the holes in the mask. | 11-25-2010 |
| 20100320475 | ETCHING TECHNIQUE FOR THE FABRICATION OF THIN (Al, In, Ga)N LAYERS - An etching technique for the fabrication of thin (Al, In, Ga)N layers. A suitable template or substrate is selected and implanted with foreign ions over a desired area to create ion implanted material. A regrowth of a device structure is then performed on the implanted template or substrate. The top growth surface of the template is bonded to a carrier wafer to created a bonded template/carrier wafer structure. The substrate is removed, as is any residual material, to expose the ion implanted material. The ion implanted material on the bonded template/carrier wafer structure is then exposed to a suitable etchant for a sufficient time to remove the ion implanted material. | 12-23-2010 |
| 20110007766 | STRUCTURE FOR IMPROVING THE MIRROR FACET CLEAVING YIELD OF (Ga,Al,In,B)N LASER DIODES GROWN ON NONPOLAR OR SEMIPOLAR (Ga,Al,In,B)N SUBSTRATES - A structure for improving the mirror facet cleaving yield of (Ga,Al,In,B)N laser diodes grown on nonpolar or semipolar (Ga,Al,In,B)N substrates. The structure comprises a nonpolar or semipolar (Ga,Al,In,B)N laser diode including a waveguide core that provides sufficient optical confinement for the device's operation in the absence of p-type doped aluminum-containing waveguide cladding layers, and one of more n-type doped aluminum-containing layers that can be used to assist with facet cleaving along a particular crystallographic plane. | 01-13-2011 |
| 20110012234 | METHOD FOR GROWTH OF SEMIPOLAR (AL,IN,GA,B)N OPTOELECTRONIC DEVICES - A method of fabricating an optoelectronic device, comprising growing an active layer of the device on an oblique surface of a suitable material, wherein the oblique surface comprises a facetted surface. The present invention also discloses a method of fabricating the facetted surfaces. One fabrication process comprises growing an epitaxial layer on a suitable material, etching the epitaxial layer through a mask to form the facets having a specific crystal orientation, and depositing one or more active layers on the facets. Another method comprises growing a layer of material using a lateral overgrowth technique to produce a facetted surface, and depositing one or more active layers on the facetted surfaces. The facetted surfaces are typically semipolar planes. | 01-20-2011 |
| 20110032965 | OPTIMIZATION OF LASER BAR ORIENTATION FOR NONPOLAR AND SEMIPOLAR (Ga,Al,In,B)N DIODE LASERS - Optical gain of a nonpolar or semipolar Group-III nitride diode laser is controlled by orienting an axis of light propagation in relation to an optical polarization direction or crystallographic orientation of the diode laser. The axis of light propagation is substantially perpendicular to the mirror facets of the diode laser, and the optical polarization direction is determined by the crystallographic orientation of the diode laser. To maximize optical gain, the axis of light propagation is oriented substantially perpendicular to the optical polarization direction or crystallographic orientation. | 02-10-2011 |
| 20110037052 | METALORGANIC CHEMICAL VAPOR DEPOSITION (MOCVD) GROWTH OF HIGH PERFORMANCE NON-POLAR III-NITRIDE OPTICAL DEVICES - A method of device growth and p-contact processing that produces improved performance for non-polar III-nitride light emitting diodes and laser diodes. Key components using a low defect density substrate or template, thick quantum wells, a low temperature p-type III-nitride growth technique, and a transparent conducting oxide for the electrodes. | 02-17-2011 |
| 20110037085 | THIN P-TYPE GALLIUM NITRIDE AND ALUMINUM GALLIUM NITRIDE ELECTRON-BLOCKING LAYER FREE GALLIUM NITRIDE-BASED LIGHT EMITTING DIODES - A light emitting diode (LED) having a p-type layer having a thickness of 100 nm or less, an n-type layer, and an active layer, positioned between the p-type layer and the n-type layer, for emitting light, wherein the LED does not include a separate electron blocking layer. | 02-17-2011 |
| 20110044364 | STRUCTURE AND METHOD FOR ACHIEVING SELECTIVE ETCHING IN (Ga,Al,In,B)N LASER DIODES - A structure and method that can be used to achieve selective etching in (Ga, Al, In, B) N laser diodes, comprising fabricating (Ga, Al, In, B) N laser diodes with one or more Al-containing etch stop layers. | 02-24-2011 |
| 20110062415 | ANISOTROPIC STRAIN CONTROL IN SEMIPOLAR NITRIDE QUANTUM WELLS BY PARTIALLY OR FULLY RELAXED ALUMINUM INDIUM GALLIUM NITRIDE LAYERS WITH MISFIT DISLOCATIONS - An epitaxial structure for a III-Nitride based optical device, comprising an active layer with anisotropic strain on an underlying layer, where a lattice constant and strain in the underlying layer are partially or fully relaxed in at least one direction due to a presence of misfit dislocations, so that the anisotropic strain in the active layer is modulated by the underlying layer. | 03-17-2011 |
| 20110062449 | TECHNIQUE FOR THE GROWTH AND FABRICATION OF SEMIPOLAR (GA,AL,IN,B)N THIN FILMS, HETEROSTRUCTURES, AND DEVICES - A method for growth and fabrication of semipolar (Ga, Al, In, B)N thin films, heterostructures, and devices, comprising identifying desired material properties for a particular device application, selecting a semipolar growth orientation based on the desired material properties, selecting a suitable substrate for growth of the selected semipolar growth orientation, growing a planar semipolar (Ga, Al, In, B)N template or nucleation layer on the substrate, and growing the semipolar (Ga, Al, In, B)N thin films, heterostructures or devices on the planar semipolar (Ga, Al, In, B)N template or nucleation layer. The method results in a large area of the semipolar (Ga, Al, In, B)N thin films, heterostructures, and devices being parallel to the substrate surface. | 03-17-2011 |
| 20110064103 | SEMIPOLAR NITRIDE-BASED DEVICES ON PARTIALLY OR FULLY RELAXED ALLOYS WITH MISFIT DISLOCATIONS AT THE HETEROINTERFACE - A dislocation-free high quality template with relaxed lattice constant, fabricated by spatially restricting misfit dislocation(s) around heterointerfaces. This can be used as a template layer for high In composition devices. Specifically, the present invention prepares high quality InGaN templates (In composition is around 5-10%), and can grow much higher In-composition InGaN quantum wells (QWs) (or multi quantum wells (MQWs)) on these templates than would otherwise be possible. | 03-17-2011 |
| 20110103418 | SUPERLUMINESCENT DIODES BY CRYSTALLOGRAPHIC ETCHING - An optoelectronic device, comprising an active region and a waveguide structure to provide optical confinement of light emitted from the active region; a pair of facets on opposite ends of the device, having opposite surface polarity; and one of the facets which has been roughened by a crystallographic chemical etching process, wherein the device is a nonpolar or semipolar (Ga,In,Al,B)N based device. | 05-05-2011 |
| 20110108886 | METHOD OF CONTROLLING STRESS IN GROUP-III NITRIDE FILMS DEPOSITED ON SUBSTRATES - Methods of controlling stress in GaN films deposited on silicon and silicon carbide substrates and the films produced therefrom are disclosed. A typical method comprises providing a substrate and depositing a graded gallium nitride layer on the substrate having a varying composition of a substantially continuous grade from an initial composition to a final composition formed from a supply of at least one precursor in a growth chamber without any interruption in the supply. A typical semiconductor film comprises a substrate and a graded gallium nitride layer deposited on the substrate having a varying composition of a substantially continuous grade from an initial composition to a final composition formed from a supply of at least one precursor in a growth chamber without any interruption in the supply. | 05-12-2011 |
