Abstract: Disclosed is a light emitting device including a substrate, a first buffer layer disposed on the substrate, the first buffer layer comprising aluminum nitride (AlN), an insertion layer disposed on the first buffer layer, the insertion layer comprising aluminum (Al), and a light emitting structure disposed on the insertion layer, the light emitting structure comprising a first semiconductor layer, a second semiconductor layer, and an active layer interposed between the first semiconductor layer and the second semiconductor layer.
Type:
Application
Filed:
February 6, 2012
Publication date:
June 7, 2012
Inventors:
Seungkeun Nam, Junghun Jang, Jeongsik Lee
Abstract: A method for producing a Group III nitride semiconductor light-emitting device includes forming a first stripe-pattern embossment on the top surface of a sapphire substrate, so that first grooves parallel to the x-axis direction (the c-axis direction of the sapphire substrate) are periodically arranged at specific intervals. Subsequently, an insulating film is formed over the entire surface of the first stripe-pattern embossment. Next, a second stripe-pattern embossment is formed so that second grooves, each having a flat bottom surface, are periodically arranged at specific intervals and parallel to the y-axis direction, which is orthogonal to the x-axis direction. A GaN crystal is grown through MOCVD on side surfaces of each second groove of the sapphire substrate, to thereby form, on the sapphire substrate, an m-plane GaN base layer. An LED device structure is formed on the base layer, to thereby produce a light-emitting device.
Abstract: A III-nitride light emitting diode grown on a semipolar {20-2-1} plane of a substrate and characterized by high power, high efficiency and low efficiency droop.
Type:
Application
Filed:
October 27, 2011
Publication date:
May 24, 2012
Applicant:
THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
Inventors:
Yuji Zhao, Junichi Sonoda, Chih-Chien Pan, Shinichi Tanaka, Steven P. DenBaars, Shuji Nakamura
Abstract: An electrical device includes a charge carrier transport layer formed using a ternary semiconducting compound having a stoichiometry of 1:1:1 and an element combination selected from the set of I-II-V, I-III-IV, II-II-IV, and I-I-VI; or having a stoichiometry of 3:1:2 and an element combination selected from the set of I-III-V; or having a stoichiometry of 2:1:1 and an element combination selected from the set of I-II-IV. In some embodiments, the charge carrier transport layer is used as the radiation absorption layer for a photovoltaic cell, or a light emitting layer of a light emitting device. Other devices, such as laser diode, a photodetection device, an optical modulator, a transparent electrode and a window layer, can also be formed using the ternary semiconducting compound as the charge carrier transport.
Type:
Application
Filed:
November 17, 2011
Publication date:
May 24, 2012
Applicant:
The Board of Trustees of the Leland Stanford Junior University
Abstract: Provided are a light emitting device, a light emitting device package, and a lighting apparatus. The light emitting device includes: an n-type semiconductor layer including a first area and a second area in a plane; an n-type contact layer disposed on the n-type semiconductor layer and has a first thickness in the first area and a second thickness in the second area; an undoped semiconductor layer disposed on the n-type contact layer having the first thickness in the first area; an active layer disposed on the undoped semiconductor layer in the first area; a p-type semiconductor layer disposed on the active layer in the first area; a first electrode disposed on the n-type contact layer having the second thickness in the second area; and a second electrode disposed on the p-type semiconductor layer.
Abstract: Provided are a light emitting device, a light emitting device package, and a lighting system. The light emitting device comprises a first conductive type first semiconductor layer, an active layer, a second conductive type second semiconductor layer, a reliability enhancement layer, and a second conductive type third semiconductor layer. The active layer is disposed on the first conductive type first semiconductor layer. The second conductive type second semiconductor layer is disposed on the active layer. The reliability enhancement layer is disposed on the second conductive type second semiconductor layer. The second conductive type third semiconductor layer is disposed on the reliability enhancement layer and comprises a light extraction pattern. The reliability enhancement layer and the active layer are spaced apart from each other by a distance of 0.3 ?m to 5 ?m.
Type:
Application
Filed:
January 25, 2012
Publication date:
May 17, 2012
Inventors:
Yong Tae MOON, Yong Seon Song, Sung Hoon Jung, Joong Seo Park, Sang Jun Lee, Jeong Tak Oh, Rak Jun Choi
Abstract: A light emitting device includes a pair of electrodes facing to each other and a phosphor layer which is sandwiched between the pair of electrodes and includes phosphor particles placed therein. The phosphor particles include an n-type nitride semiconductor part and a p-type nitride semiconductor part, the n-type nitride semiconductor part and the p-type nitride semiconductor part are made of respective single crystals having wurtzite-type crystal structures having c axes parallel with each other, and the phosphor particles include an insulation layer provided to overlie one end surface out of their end surfaces perpendicular to the c axes.
Abstract: A method for production of a plurality of semiconductor chips (6) in a wafer composite. A semiconductor layer sequence (2) is grown on a growth substrate (1), metallization (3) is applied to the semiconductor layer sequence (2), a metal layer (4) is electrochemically deposited onto the metallization (3), and the semiconductor layer sequence (2) is then structured and separated to form individual semiconductor chips (6). The electrochemically applied metal layer (4) is particularly suitable for use as a heat spreader, for dissipation of the heat produced by the semiconductor chips (6).
Type:
Grant
Filed:
September 28, 2006
Date of Patent:
May 15, 2012
Assignee:
OSRAM Opto Semiconductors GmbH
Inventors:
Stephan Lutgen, Tony Albrecht, Wolfgang Reill
Abstract: For a nitride semiconductor light emitting device, a c-axis vector of hexagonal GaN of a support substrate is inclined to an X-axis direction with respect to a normal axis Nx normal to a primary surface. In a semiconductor region an active layer, a first gallium nitride-based semiconductor layer, an electron block layer, and a second gallium nitride-based semiconductor layer are arranged along the normal axis on the primary surface of the support substrate. A p-type cladding layer is comprised of AlGaN, and the electron block layer is comprised of AlGaN. The electron block layer is subject to tensile strain in the X-axis direction. The first gallium nitride-based semiconductor layer is subject to compressive strain in the X-axis direction. The misfit dislocation density at an interface is smaller than that at an interface. A barrier to electrons at the interface is raised by piezoelectric polarization.
Abstract: Provided is a Group III nitride semiconductor device, which comprises an electrically conductive substrate including a primary surface comprised of a first gallium nitride based semiconductor, and a Group III nitride semiconductor region including a first p-type gallium nitride based semiconductor layer and provided on the primary surface. The primary surface of the substrate is inclined at an angle in the range of not less than 50 degrees, and less than 130 degrees from a plane perpendicular to a reference axis extending along the c-axis of the first gallium nitride based semiconductor, an oxygen concentration Noxg of the first p-type gallium nitride based semiconductor layer is not more than 5×1017 cm?3, and a ratio (Noxg/Npd) of the oxygen concentration Noxg to a p-type dopant concentration Npd of the first p-type gallium nitride based semiconductor layer is not more than 1/10.
Abstract: Provided is a Group III nitride semiconductor laser diode with a cladding layer capable of providing high optical confinement and carrier confinement. An n-type Al0.08Ga0.92N cladding layer is grown so as to be lattice-relaxed on a (20-21)-plane GaN substrate. A GaN optical guiding layer is grown so as to be lattice-relaxed on the n-type cladding layer. An active layer, a GaN optical guiding layer, an Al0.12Ga0.88N electron blocking layer, and a GaN optical guiding layer are grown so as not to be lattice-relaxed on the optical guiding layer. A p-type Al0.08Ga0.92N cladding layer is grown so as to be lattice-relaxed on the optical guiding layer. A p-type GaN contact layer is grown so as not to be lattice-relaxed on the p-type cladding layer, to produce a semiconductor laser. Dislocation densities at junctions are larger than those at the other junctions.
Abstract: A method for fabricating a III-nitride semiconductor film, comprising depositing or growing a III-nitride semiconductor film in a semiconductor light absorbing or light emitting device structure; and growing a textured or structured surface of the III-nitride nitride semiconductor film in situ with the growing or the deposition of the III-nitride semiconductor film, by controlling the growing of the III-nitride semiconductor film to obtain a texture of the textured surface, or one or more structures of the structured surface, that increase output power of light from the light emitting device, or increase absorption of light in the light absorbing device.
Type:
Application
Filed:
October 27, 2011
Publication date:
May 3, 2012
Applicant:
THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
Inventors:
Michael Iza, Carl J. Neufeld, Samantha C. Cruz, Robert M. Farrell, James S. Speck, Shuji Nakamura, Steven P. DenBaars, Umesh K. Mishra
Abstract: A method of fabricating group-III nitride semiconductor laser device includes: preparing a substrate comprising a hexagonal group-III nitride semiconductor and having a semipolar principal surface; forming a substrate product having a laser structure, an anode electrode, and a cathode electrode, where the laser structure includes a semiconductor region and the substrate, where the semiconductor region is formed on the semipolar principal surface; scribing a first surface of the substrate product in a direction of an a-axis of the hexagonal group-III nitride semiconductor to form first and second scribed grooves; and carrying out breakup of the substrate product by press against a second surface of the substrate product, to form another substrate product and a laser bar.
Abstract: According to one embodiment, a method is disclosed for manufacturing a semiconductor light emitting device. The method can include a crystal growth process. The crystal growth process is configured to grow a stacked structure of compound semiconductor composed of a group III element and a group V element on a substrate by a metal organic chemical vapor deposition process. The substrate is mounted on a substrate mounting portion provided on a surface of a tray placed above a heating device. A compound semiconductor film includes at least one group III element forming the stacked structure and at least one group V element forming the stacked structure. The compound semiconductor film is previously formed on a surface of the substrate mounting portion before growing the stacked structure. The substrate is mounted on the substrate mounting portion via the compound semiconductor film, and the stacked structure is grown on the substrate.
Abstract: The light emitting semiconductor device (1) of the present invention is made of nitrides of group III metals and comprises a layer structure comprising an n-type semiconductor layer (2), a p-type semiconductor layer (3), an active region (4) between the n-type semiconductor layer and the p-type semiconductor layer. The layer structure has a contact surface (5) defined by one of the n-type and p-type semiconductor layers and comprises further a reflective contact structure (6) attached to the contact surface. According to the present invention, the reflective contact structure (6) comprises: a first transparent conductive oxide (TCO) contact layer (13), having a poly-crystalline structure, attached to the contact surface (5) of the layer structure; a second transparent conductive oxide (TCO) contact layer (14) having an amorphous structure; and a metallic reflective layer (15) attached to the second TCO layer.
Type:
Application
Filed:
June 3, 2010
Publication date:
May 3, 2012
Inventors:
Vladislav E. Bougrov, Maxim A. Odnoblyudov, Mikael Mulot
Abstract: A light emitting diode device includes a substrate; a first conducting terminal and a second conducting terminal receiving the alternative current signal; a first and a third light-emitting diode groups disposed on the substrate including a plurality of light emitting diodes electrically connecting with the first conducting terminal and the second conducting terminal and emitting light during the positive half power cycle; a second and the third light-emitting diode groups disposed on the substrate including a plurality of light emitting diodes electrically connecting with the first conducting terminal and the second conducting terminal and emitting light during the negative half power cycle; wherein one light emitting diode in the first light-emitting diode group includes more than three conductive connecting points to electrically connect to the second light-emitting diode group and the third light-emitting diode group.
Abstract: A method of fabricating a III-nitride semiconductor laser device includes: preparing a substrate having a hexagonal III-nitride semiconductor and having a semipolar primary surface; forming a substrate product having a laser structure, an anode electrode and a cathode electrode, the laser structure including a substrate and a semiconductor region formed on the semipolar primary surface; scribing a first surface of the substrate product in part in a direction of the a-axis of the hexagonal III-nitride semiconductor; and carrying out breakup of the substrate product by press against a second surface of the substrate product, to form another substrate product and a laser bar.
Abstract: A method for fabricating a semi-polar III-nitride substrate for semi-polar III-nitride device layers, comprising providing a vicinal surface of the III-nitride substrate, so that growth of relaxed heteroepitaxial III-nitride device layers on the vicinal surface compensates for epilayer tilt of the III-nitride device layers caused by one or more misfit dislocations at one or more heterointerfaces between the device layers.
Type:
Application
Filed:
October 26, 2011
Publication date:
April 26, 2012
Applicant:
THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
Inventors:
James S. Speck, Anurag Tyagi, Alexey E. Romanov, Shuji Nakamura, Steven P. DenBaars
Abstract: An exemplary LED chip includes a substrate, a buffer layer formed on the substrate and a light emitting layer formed on the buffer layer. The light emitting layer includes an n-type semiconductor layer and a p-type semiconductor layer. A first electrode is electrically connected with one of the n-type semiconductor layer and the p-type semiconductor layer. A second electrode is electrically connected with the other one of the n-type semiconductor layer and the p-type semiconductor layer. A bonding pad is formed on a top surface of the first electrode. A bonding wire is secured to the bonding pad. A ratio between a contacting area between the bonding pad and the top surface of the first electrode and an area of the top surface of the first electrode is no less than 6:10.
Type:
Application
Filed:
July 7, 2011
Publication date:
April 26, 2012
Applicant:
ADVANCED OPTOELECTRONIC TECHNOLOGY, INC.
Abstract: A method for making a solid state semiconductor device includes: providing a substrate; forming a buffer layer on the substrate; forming a first epitaxial layer on the buffer layer; forming a surface-textured second epitaxial layer on the first epitaxial layer by chemical vapor deposition; and forming a solid state stacked layer structure having a PN-junction type light-emitting part on a textured surface of the second epitaxial layer.
Type:
Application
Filed:
June 30, 2011
Publication date:
April 26, 2012
Applicant:
ADVANCED OPTOELECTRONIC TECHNOLOGY, INC.
Abstract: A nitride-based semiconductor light-emitting device according to the present invention has a nitride-based semiconductor multilayer structure 50a, which includes: an active layer 32 including an AlaInbGacN crystal layer (where a+b+c=1, a?0, b?0 and c?0); an AldGaeN overflow suppressing layer 36 (where d+e=1, d>0, and e?0); and an AlfGagN layer 38 (where f+g=1, f?0, g?0and f<d). The AldGaeN overflow suppressing layer 36 is arranged between the active layer 32 and the AlfGagN layer 38. The AldGaeN overflow suppressing layer 36 includes an In-doped layer 35 that is doped with In at a concentration of 1×1016 atms/cm3 to 8×1018 atms/cm3. A normal to the principal surface of the nitride-based semiconductor multilayer structure 50a defines an angle of 1 to 5 degrees with respect to a normal to an m plane.
Abstract: There is provided a light emitting device that includes a base wafer that contains silicon, a plurality of seed bodies provided in contact with the base wafer, and a plurality of Group 3-5 compound semiconductors that are each lattice-matched or pseudo-lattice-matched to corresponding seed bodies. In the device, a light emitting element that emits light in response to current supplied thereto is formed in at least one of the plurality of the Group 3-5 compound semiconductors, and a current limiting element that limits the current supplied to the light emitting element is formed in at least one of the plurality of the Group 3-5 compound semiconductors other than the Group 3-5 compound semiconductor in which the light emitting element is formed.
Abstract: A method of fabricating a group-III nitride semiconductor laser device includes: preparing a substrate of a hexagonal group-III nitride semiconductor, where the substrate has a semipolar primary surface; forming a substrate product having a laser structure, an anode electrode and a cathode electrode, where the laser structure includes the substrate and a semiconductor region, and where the semiconductor region is formed on the semipolar primary surface; scribing a first surface of the substrate product in part in a direction of the a-axis of the hexagonal group-III nitride semiconductor; and carrying out breakup of the substrate product by press against a second surface of the substrate product, to form another substrate product and a laser bar.
Abstract: A method for producing a Group III nitride semiconductor light-emitting device includes an n-type layer, a light-emitting layer, and a p-type layer, each of the layers being formed of Group III nitride semiconductor, being sequentially deposited via a buffer layer on a textured sapphire substrate. A buried layer is formed of Group III nitride semiconductor on the buffer layer, at a temperature lower by 20° C. to 80° C. than the temperature of 1000° C. to 1200° C. when the n-type layer is deposited on the buried layer. The texture provided on the sapphire substrate may have a depth of 1 ?m to 2 ?m and a side surface inclined by 40° to 80°. A preventing layer may be formed of GaN at 600° C. to 1050° C. so as to cover the entire top surface of the buffer layer.
Abstract: A structure of semiconductor device includes a first semiconductor layer; an intermediate layer on a surface of said first semiconductor layer; a second semiconductor layer on said intermediate layer, wherein said intermediate layer and said second semiconductor layer are integrated to a set of sub-structures; and a semiconductor light emitting device on said second semiconductor layer.
Type:
Application
Filed:
December 8, 2011
Publication date:
April 5, 2012
Applicant:
ADVANCED OPTOELECTRONIC TECHNOLOGY, INC.
Inventors:
SHIH CHENG HUANG, PO MIN TU, YING CHAO YEH, WEN YU LIN, PENG YI WU, SHIH HSIUNG CHAN
Abstract: A light-emitting diode having a high output, high efficiency, and a long service life under a high-humidity environment is provided. The light-emitting diode (1) includes a compound semiconductor layer (2) having a light-emitting section (7), ohmic electrodes (4, 5) provided on the main light extraction surface of the compound semiconductor layer (2), and an electrode protection layer (6) for protecting the ohmic electrodes (4, 5), wherein the Al concentrations of the surfaces (2a, 2b) of the compound semiconductor layer (2), which include the main light extraction surface, are 20% or less and the As concentration of the surfaces (2a, 2b) is less than 1%, and the electrode protection layer (6) has a two-layer structure composed of a first protective film (12) provided so as to cover the ohmic electrodes (4, 5) and a second protective film (13) provided so as to cover at least an end portion of the first protective film (12).
Abstract: Gallium nitride (GaN) based semiconductor devices and methods of manufacturing the same. The GaN-based semiconductor device may include a conductive heat dissipation substrate (that is, a thermal conductive substrate); an GaN-based multi-layer arranged on the heat dissipation substrate; and a Schottky electrode arranged on the GaN-based multi-layer. While such a GaN-based semiconductor device is being manufactured, a wafer bonding process and a laser lift-off process may be used.
Abstract: Disclosed is a light emitting device. The light emitting device includes a substrate, a semiconductor layer on the substrate, and an electrode on the semiconductor layer, wherein the substrate has at least one side surface having a predetermined tilt angle with respect to a bottom surface of the substrate, wherein the predetermined tilt angle is an obtuse angle, and wherein a side surface of the semiconductor layer disposes vertically.
Abstract: The sapphire substrate has a principal surface for growing a nitride semiconductor to form a nitride semiconductor light emitting device and comprising a plurality of projections of the principal surface, wherein an outer periphery of a bottom surface of each of the projections has at least one depression. This depression is in the horizontal direction. The plurality of projections are arranged so that a straight line passes through the inside of at least any one of projections when the straight line is drawn at any position in any direction in a plane including the bottom surfaces of the plurality of projections.
Abstract: The invention is applicable for use in conjunction with a light-emitting semiconductor structure that includes a semiconductor active region of a first conductivity type containing a quantum size region and having a first surface adjacent a semiconductor input region of a second conductivity type that is operative, upon application of electrical potentials with respect to the active and input regions, to produce light emission from the active region. A method is provided that includes the following steps: providing a semiconductor output region that includes a semiconductor auxiliary layer of the first conductivity type adjacent a second surface, which opposes the first surface of the active region, and providing the auxiliary layer as a semiconductor material having a diffusion length for minority carriers of the first conductivity type material that is substantially shorter than the diffusion length for minority carriers of the semiconductor material of the active region.
Abstract: A group III nitride nanorod light emitting device and a method of manufacturing thereof. The method includes preparing a substrate, forming an insulating film including one or more openings exposing parts of the substrate on the substrate, growing first conductive group III nitride nanorod seed layers on the substrate exposed through the openings by supplying a group III source gas and a nitrogen (N) source gas thereto, growing first conductive group III nitride nanorods on the first conductive group III nitride nanorod seed layers by supplying the group III source gas and an impurity source gas in a pulse mode and continuously supplying the N source gas, forming an active layer on a surface of each of the first conductive group III nitride nanorods, and forming a second conductive nitride semiconductor layer on the active layer.
Type:
Application
Filed:
September 13, 2011
Publication date:
March 22, 2012
Inventors:
Han Kyu Seong, Hun Jae Chung, Jung Ja Yang, Cheol Soo Sone
Abstract: The present invention provides a semiconductor light-emitting device that includes a compound semiconductor layer formed by laminating a first clad layer, a light-emitting layer and a second clad layer, a plurality of first ohmic electrodes formed on the first clad layer, a plurality of second ohmic electrodes formed on the second clad layer, a transparent conductive film that is formed on the first clad layer of the compound semiconductor layer and is conductively connected to the first ohmic electrodes, a bonding electrode formed on the transparent conducting film, and a support plate that is positioned on the second clad layer side of the compound semiconductor layer and is conductively connected to the second ohmic electrodes.
Abstract: A gallium nitride (GaN) light emitting device and a method of manufacturing the same are provided, the method including sequentially forming a buffer layer and a first nitride layer on a silicon substrate, and forming a plurality of patterns by dry etching the first nitride layer. Each pattern includes a pair of sidewalls facing each other. A reflective layer is deposited on the first nitride layer so that one sidewall of the pair is exposed by the reflective layer. An n-type nitride layer that covers the first nitride layer is formed by horizontally growing an n-type nitride from the exposed sidewall, and a GaN-based light emitting structure layer is formed on the n-type nitride layer.
Type:
Grant
Filed:
May 12, 2010
Date of Patent:
March 20, 2012
Assignee:
Samsung Electronics Co., Ltd.
Inventors:
Young-jo Tak, Jun-youn Kim, Hyun-gi Hong, Jae-won Lee, Hyung-su Jeong
Abstract: A high-power and high-efficiency light emitting device with emission wavelength (?peak) ranging from 280 nm to 360 nm is fabricated. The new device structure uses non-polar or semi-polar AlInN and AlInGaN alloys grown on a non-polar or semi-polar bulk GaN substrate.
Type:
Application
Filed:
November 21, 2011
Publication date:
March 15, 2012
Applicant:
THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
Inventors:
Roy B. Chung, Zhen Chen, James S. Speck, Steven P. DenBaars, Shuji Nakamura
Abstract: Method of producing a photonic device including at least one light source and at least one photodetector on a structure including a waveguide layer, this method comprising the following steps: a) growing successively on a substrate (10), a photodetection structure (11) and a light source structure (12), the photodetection structure and the light source structure being made of a stack of layers, the light source layers being stacked on top of the photodetector layers and both structures sharing one of these layers.
Type:
Application
Filed:
February 1, 2010
Publication date:
March 15, 2012
Applicants:
CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE, COMMISSARIAT A L'ENERGIE ATOMIQUE ET AUX ENERGIES ALTERNATIVES
Inventors:
Laurent Grenouillet, Jean-Marc Fedeli, Liu Liu, Regis Orobtchouk, Philippe Regreny, Gunther Roelkens, Pedro Rojo-Romeo, Dries Van Thourhout
Abstract: A method for manufacturing a nitride semiconductor device such as a nitride semiconductor light emitting device, a transistor device or the like. The method includes the steps of forming a buffer crystalline layer of the nitride semiconductor made of AlxGayIn1-x-yN (0?x?1, 0?y ?1 and 0?x+y?1), in which both an a-axis and a c-axis are aligned, directly on a substrate lattice-mismatched with the nitride semiconductor without forming an amorphous low temperature buffer layer, by plasma laser deposition(PLD) method, and growing epitaxially the nitride semiconductor layer on the buffer layer so as to form a device such as a nitride semiconductor light emitting diode, by metal organic chemical vapor deposition (MOCVD).
Abstract: A GaN-based semiconductor light emitting device 11a includes a substrate 13 composed of a GaN-based semiconductor having a primary surface 13a tilting from the c-plane toward the m-axis at a tilt angle ? of more than or equal to 63 degrees and less than 80 degrees, a GaN-based semiconductor epitaxial region 15, an active layer 17, an electron blocking layer 27, and a contact layer 29. The active layer 17 is composed of a GaN-based semiconductor containing indium. The substrate 13 has a dislocation density of 1×107 cm?2 or less. In the GaN-based semiconductor light emitting device 11a provided with the active layer containing indium, a decrease in quantum efficiency under high current injection can be moderated.
Abstract: Favorable-quality III-V crystals are easily obtained at low cost without causing cracks, even when using a variety of substrates, and can be used to manufacture semiconductor devices with good quality and at high yields. The III-V crystals are characterized by the following properties: the carrier concentration, resistivity, and dislocation density of the III-V compound crystal are uniform to within ±30% variation along the surface; the III-V compound crystal is misoriented from the c-plane such that the crystal surface does not include any region where its off-axis angle with the c-plane is 0°; and the full width at half-maximum in XRD at the crystal center of the III-V compound is not greater than 150 arcsec.
Type:
Grant
Filed:
November 13, 2009
Date of Patent:
March 13, 2012
Assignee:
Sumitomo Electric Industries, Ltd.
Inventors:
Seiji Nakahata, Koji Uematsu, Ryu Hirota
Abstract: A light emitting device is provided. In the light emitting device, a multi-layer for intercepting a reverse voltage applied to an active layer is formed between the active layer and a GaN layer. Accordingly, the reliability and operational characteristic of the light emitting device can be improved.
Abstract: According to one embodiment, in a light emitting device, a substrate is transparent to a wavelength of emitted light. A first dielectric layer is formed in a first region on the substrate, and has a refractive index smaller than a refractive index of the substrate. A second dielectric layer is formed in a second region on the substrate surrounding the first region, and has a refractive index larger than the refractive index of the substrate. A first semiconductor layer is formed on the first dielectric layer, the second dielectric layer and the substrate. A second semiconductor layer is formed on the first semiconductor layer, and includes an active layer having a PN junction.
Abstract: A semiconductor compound structure and a method of fabricating the semiconductor compound structure using graphene or carbon nanotubes, and a semiconductor device including the semiconductor compound structure. The semiconductor compound structure includes a substrate; a buffer layer disposed on the substrate, and formed of a material including carbons having hexagonal crystal structures; and a semiconductor compound layer grown and formed on the buffer layer.
Type:
Application
Filed:
April 27, 2011
Publication date:
March 8, 2012
Applicant:
SAMSUNG ELECTRONICS CO., LTD.
Inventors:
Jun-hee CHOI, Un-jeong KIM, Sang-jin LEE
Abstract: An (Al,Ga,In)N-based light emitting diode (LED), comprising a p-type surface of the LED bonded with a transparent submount material to increase light extraction at the p-type surface, wherein the LED is a substrateless membrane.
Type:
Application
Filed:
November 15, 2011
Publication date:
March 8, 2012
Applicant:
THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
Inventors:
Kenji Iso, Hirokuni Asamizu, Makoto Saito, Hitoshi Sato, Steven P. DenBaars, Shuji Nakamura
Abstract: A semiconductor sensor, solar cell or emitter, or a precursor therefor, has a substrate and one or more textured semiconductor layers deposited onto the substrate. The textured layers enhance light extraction or absorption. Texturing in the region of multiple quantum wells greatly enhances internal quantum efficiency if the semiconductor is polar and the quantum wells are grown along the polar direction. Electroluminescence of LEDs of the invention is dichromatic, and results in variable color LEDs, including white LEDs, without the use of phosphor.
Type:
Application
Filed:
September 23, 2011
Publication date:
March 8, 2012
Inventors:
Theodore D. Moustakas, Jasper S. Cabalu
Abstract: A method for enhancing light extraction of a light emitting device is disclosed. The method includes the steps of: providing a site layer on the light emitting device; placing a protection layer on the site layer; forming an array of pores through the protection layer and the site layer; and growing on the site layer an oxide layer, having a plurality of rods, each of which is formed in one of the pores. The shapes of the rods can be well controlled by adjusting reactive temperature, time and N2/H2 concentration ratio of atmosphere such that the shape and light escape angle of the rods can be changed.
Abstract: This invention provides a self supporting substrate which consists of a n-type conductive aluminum nitride semiconductor crystal and is useful for manufacturing the vertical conductive type AlN semiconductor device. The n-type conductive aluminum nitride semiconductor crystal, by which the self supporting substrate is made up, contains Si atom at a concentration of 1×1018 to 5×1020 cm?3 is substantially free of halogen atoms and substantially does not absorb the light having the energy of not more than 5.9 eV. The self supporting substrate can be obtained by a method comprising the steps of forming an AlN crystal layer on a single crystal substrate such as a sapphire by the HVPE method, preheating the obtained substrate having the AlN crystal layer to a temperature of 1,200° C. or more, forming a second layer consisting of the n-type conductive aluminum nitride semiconductor crystal is formed on the AlN crystal layer in high rate by the HVPE method and separating the second layer from the obtained laminate.
Type:
Grant
Filed:
February 2, 2008
Date of Patent:
March 6, 2012
Assignees:
Tokuyama Corporation, Tokyo University of Agriculture and Technology
Abstract: The invention provides a liquid fluorescent composition. The liquid fluorescent composition includes at least (a) 0.001-2 parts by weight of a fluorescent material; and (b) 100 parts by weight of a cyclic solvent having a boiling point above 100° C. The invention also provides a light emitting device containing the above liquid fluorescent composition.
Abstract: The present invention discloses a high-reflectivity and low-defect density LED structure. A patterned dielectric layer is embedded in a sapphire substrate via semiconductor processes, such as etching and deposition. The dielectric layer is formed of two materials which are alternately stacked and have different refractive indexes. An N-type semiconductor layer, an activation layer and a light emitting layer which is a P-type semiconductor layer are sequentially formed on the sapphire substrate. An N-type electrode and a P-type electrode are respectively coated on the N-type semiconductor layer and the P-type semiconductor layer. The dielectric layer can lower the defect density of the light emitting layer during the epitaxial growth process. Further, the dielectric layer can function as a high-reflectivity area to reflect light generated by the light emitting layer and the light is projected downward to be emitted from the top or the lateral. Thereby is greatly increased the light-extraction efficiency.
Abstract: The present disclosure relates to a III-nitride semiconductor light-emitting device including a substrate with a first groove and a second groove formed therein, the substrate including a first surface and a second surface opposite to the first surface, a plurality of III-nitride semiconductor layers including a first semiconductor layer formed over the first surface of the substrate, a second semiconductor layer formed over the first III-nitride semiconductor layer, and an active layer disposed between the first and second III-nitride semiconductor layers and generating light by recombination of electrons and holes, a first opening formed on the first groove, a second opening formed on the second groove, a first electrode electrically connected from the second surface to the first III-nitride semiconductor layer through the first groove, and a second electrode electrically connected from the second surface to the second III-nitride semiconductor layer through the second groove and the second opening.
Abstract: Presented is a method for producing an optoelectronic component. The method includes separating a semiconductor layer based on a III-V-compound semiconductor material from a substrate by irradiation with a laser beam having a plateau-like spatial beam profile, where individual regions of the semiconductor layer are irradiated successively.
Type:
Application
Filed:
October 26, 2011
Publication date:
February 16, 2012
Applicant:
Osram Opto Semiconductors GmbH
Inventors:
Michael FEHRER, Berthold Hahn, Volker Härle, Stephan Kajser, Frank Otte, Andreas Plössl
Abstract: A light emitting diode and a fabricating method thereof are provided. A first-type semiconductor layer, a light emitting layer and a second-type semiconductor layer with a first surface are sequentially formed a substrate. Next, the first surface is treated during a surface treatment process to form a current-blocking region which extends from the first surface to the light emitting layer to a depth of 1000 angstroms. Afterward, a first electrode is formed above the current-blocking region of the second-type semiconductor layer, and a second electrode is formed to electrically contact to the first-type semiconductor layer. Since the current-blocking region is formed with a determined depth within the second-type semiconductor layer, the light extraction efficiency of the light emitting diode may be increased.
Type:
Application
Filed:
February 17, 2011
Publication date:
February 16, 2012
Applicant:
Lextar Electronics Corporation
Inventors:
Mong-Ea Lin, Yao-Hui Lin, Chao-Ming Chiu, Chang-Ming Lu