Multiple Quantum Well Structure (epo) Patents (Class 257/E31.033)
  • Patent number: 10585239
    Abstract: A photodiode (PD) device that monolithically integrates a PD element with a waveguide element is disclosed. The PD device includes a conducting layer with a first region and a second region next to the first region, where the PD element exists in the first region, while, the waveguide element exists in the second region and optically couples with the PD element. The waveguide element includes a core layer and a cladding layer on the conducting layer, which forms an optical confinement structure. The PD element includes an absorption layer on the conducting layer and a p-type cladding layer on the absorption layer, which form another optical confinement structure. The absorption layer has a length at least 12 ?m measured from the interface against the core layer.
    Type: Grant
    Filed: March 1, 2019
    Date of Patent: March 10, 2020
    Assignee: Sumitomo Electric Device Innovations, Inc.
    Inventors: Yoshihiro Yoneda, Takuya Okimoto, Kenji Sakurai
  • Patent number: 10297701
    Abstract: An optical switching device includes: an optical absorbing layer having a first superlattice structure and responding to an incident light; an excitation layer having a second superlattice structure and producing an electron by thermal excitation; and a barrier layer having a third superlattice structure, the optical absorbing layer and the barrier layer enabling a first band offset and a second band offset to form a well in a conduction band of the second superlattice structure of the excitation layer with reference to a conduction band of the first superlattice structure of the optical absorbing layer and a conduction band of the third superlattice structure of the barrier layer, respectively.
    Type: Grant
    Filed: January 30, 2018
    Date of Patent: May 21, 2019
    Assignee: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Sundararajan Balasekaran, Kohei Miura
  • Patent number: 9728473
    Abstract: A method of manufacturing a semiconductor device includes forming a film along a surface of a semiconductor substrate in a first surface area state having a first surface area by supplying a reaction gas at a first flow rate. The method further includes detecting a transition from the first surface area state to a second surface area state having a second surface area different from the first surface area. The method still further includes forming the film by changing the flow rate of the reaction gas from the first flow rate to a second flow rate different from the first flow rate after detecting the transition from the first surface area state to the second surface area state.
    Type: Grant
    Filed: March 2, 2015
    Date of Patent: August 8, 2017
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masayuki Kitamura, Atsuko Sakata, Satoshi Wakatsuki
  • Patent number: 9478942
    Abstract: A ring cavity light-emitting transistor device, including: a planar semiconductor structure of a semiconductor base layer of a first conductivity type between semiconductor collector and emitter layers of a second conductivity type; base, collector, and emitter metalizations respectively coupled with the base layer, said collector layer, and said emitter layer, the base metalization including at least one annular ring coupled with a surface of the base layer; and an annular ring-shaped optical resonator in a region of the semiconductor structure generally including the interface of the base and emitter regions; whereby application of electrical signals with respect to the base, collector, and emitter metalizations causes light emission in the base layer that propagates in the ring-shaped optical resonator cavity.
    Type: Grant
    Filed: May 26, 2015
    Date of Patent: October 25, 2016
    Assignee: The Board of Trustees of The University of Illinois
    Inventors: Milton Feng, Nick Holonyak, Jr., Mong-Kai Wu
  • Patent number: 9040955
    Abstract: Provided are a semiconductor device and an optical sensor device, each having reduced dark current, and detectivity extended toward longer wavelengths in the near-infrared. Further, a method for manufacturing the semiconductor device is provided. The semiconductor device 50 includes an absorption layer 3 of a type II (GaAsSb/InGaAs) MQW structure located on an InP substrate 1, and an InP contact layer 5 located on the MQW structure. In the MQW structure, a composition x (%) of GaAsSb is not smaller than 44%, a thickness z (nm) thereof is not smaller than 3 nm, and z??0.4x+24.6 is satisfied.
    Type: Grant
    Filed: May 19, 2011
    Date of Patent: May 26, 2015
    Assignee: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Kei Fujii, Katsushi Akita, Takashi Ishizuka, Hideaki Nakahata, Yasuhiro Iguchi, Hiroshi Inada, Youichi Nagai
  • Patent number: 9012886
    Abstract: According to one embodiment, a semiconductor light emitting device includes: a first semiconductor layer; a second semiconductor layer; and a light emitting layer provided between the first and the second semiconductor layers. The first semiconductor layer includes a nitride semiconductor, and is of an n-type. The second semiconductor layer includes a nitride semiconductor, and is of a p-type. The light emitting layer includes: a first well layer; a second well layer provided between the first well layer and the second semiconductor layer; a first barrier layer provided between the first and the second well layers; and a first Al containing layer contacting the second well layer between the first barrier layer and the second well layer and containing layer containing Alx1Ga1-x1N (0.1?x1?0.35).
    Type: Grant
    Filed: March 14, 2013
    Date of Patent: April 21, 2015
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Jongil Hwang, Shinji Saito, Rei Hashimoto, Shinya Nunoue
  • Patent number: 8981343
    Abstract: A semiconductor device includes a p-type semiconductor layer, an n-type semiconductor layer, a pn junction portion at which the p-type semiconductor layer and the n-type semiconductor layer are joined to each other, and a multiple quantum barrier structure or a multiple quantum well structure that is provided in at least one of the p-type semiconductor layer and the n-type semiconductor layer and functions as a barrier against at least one of electrons and holes upon biasing in a forward direction. Upon biasing in a reverse direction, a portion that allows band-to-band tunneling of electrons is formed at the pn junction portion.
    Type: Grant
    Filed: January 16, 2013
    Date of Patent: March 17, 2015
    Assignee: Fujitsu Limited
    Inventor: Tsuyoshi Takahashi
  • Patent number: 8901412
    Abstract: The disclosure relates to multiple quantum well (MQW) structures for intrinsic regions of monolithic photovoltaic junctions within solar cells which are substantially lattice matched to GaAs or Ge. The disclosed MQW structures incorporate quantum wells formed of quaternary InGaAsP, between barriers of InGaP.
    Type: Grant
    Filed: September 28, 2009
    Date of Patent: December 2, 2014
    Assignee: JDS Uniphase Corporation
    Inventor: John Roberts
  • Patent number: 8890113
    Abstract: A light-emitting device epitaxially-grown on a GaAs substrate which contains an active region composed of AlxGa1-xAs alloy or of related superlattices of this materials system is disclosed. This active region either includes tensile-strained GaP-rich insertions aimed to increase the forbidden gap of the active region targeting the bright red, orange, yellow, or green spectral ranges, or is confined by regions with GaP-rich insertions aimed to increase the barrier height for electrons in the conduction band preventing the leakage of the nonequilibrium carriers outside of the light-generation region.
    Type: Grant
    Filed: June 4, 2012
    Date of Patent: November 18, 2014
    Inventors: Nikolay Ledentsov, James Lott, Vitaly Shchukin
  • Patent number: 8883548
    Abstract: Electronic device quality Aluminum Antimonide (AlSb)-based single crystals produced by controlled atmospheric annealing are utilized in various configurations for solar cell applications. Like that of a GaAs-based solar cell devices, the AlSb-based solar cell devices as disclosed herein provides direct conversion of solar energy to electrical power.
    Type: Grant
    Filed: October 24, 2011
    Date of Patent: November 11, 2014
    Assignee: Lawrence Livermore National Security, LLC
    Inventors: John W. Sherohman, Jick Hong Yee, Arthur W. Combs, III
  • Patent number: 8822315
    Abstract: A method is disclosed for treating a silicon carbide substrate for improved epitaxial deposition thereon and for use as a precursor in the manufacture of devices such as light emitting diodes. The method includes the steps of implanting dopant atoms of a first conductivity type into the first surface of a conductive silicon carbide wafer having the same conductivity type as the implanting ions at one or more predetermined dopant concentrations and implant energies to form a dopant profile, annealing the implanted wafer, and growing an epitaxial layer on the implanted first surface of the wafer.
    Type: Grant
    Filed: December 22, 2004
    Date of Patent: September 2, 2014
    Assignee: Cree, Inc.
    Inventors: Davis Andrew McClure, Alexander Suvorov, John Adam Edmond, David Beardsley Slater, Jr.
  • Patent number: 8822977
    Abstract: A photodetector and a method of manufacturing the photodetector are provided, in which variation in sensitivity is suppressed over the near-infrared region from the short wavelength side including 1.3 ?m to the long wavelength side. The photodetector includes, on an InP substrate, an absorption layer of a type II multiple quantum well structure comprising a repeated structure of a GaAsSb layer and an InGaAs layer, and has sensitivity in the near-infrared region including wavelengths of 1.3 ?m and 2.0 ?m. The ratio of the sensitivity at the wavelength of 1.3 ?m to the sensitivity at the wavelength of 2.0 ?m is not smaller than 0.5 but not larger than 1.6.
    Type: Grant
    Filed: June 15, 2011
    Date of Patent: September 2, 2014
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Katsushi Akita, Takashi Ishizuka, Kei Fujii, Hideaki Nakahata, Youichi Nagai, Hiroshi Inada, Yasuhiro Iguchi
  • Patent number: 8822975
    Abstract: A method of manufacturing a semiconductor laser having an end face window structure, by growing over a substrate a nitride type Group III-V compound semiconductor layer including an active layer including a nitride type Group III-V compound semiconductor containing at least In and Ga, the method includes the steps of: forming a mask including an insulating film over the substrate, at least in the vicinity of the position of forming the end face window structure; and growing the nitride type Group III-V compound semiconductor layer including the active layer over a part, not covered with the mask, of the substrate.
    Type: Grant
    Filed: April 20, 2012
    Date of Patent: September 2, 2014
    Assignee: Sony Corporation
    Inventors: Masaru Kuramoto, Eiji Nakayama, Yoshitsugu Ohizumi
  • Patent number: 8816320
    Abstract: A GaN-containing semiconductor light emitting device includes: an n-type semiconductor layer formed of GaN-containing semiconductor, an active layer formed on the n-type semiconductor layer, formed of GaN-containing semiconductor, and having a multiple quantum well structure including a plurality of barrier layers and well layers stacked alternately, and a p-type semiconductor layer formed on the active layer and formed of GaN-containing semiconductor, wherein: the barrier layers comprise: a first barrier layer disposed nearest to the n-type semiconductor layer among the barrier layers and formed of a GaN/AlGaN layer, and second barrier layers disposed nearer to the p-type semiconductor layer than the first barrier layer and including an InGaN/GaN layer which has a layered structure of a InGaN sublayer and a GaN sublayer; and the well layers are each formed of an InGaN layer having a narrower band gap than that in the InGaN sublayer.
    Type: Grant
    Filed: January 17, 2013
    Date of Patent: August 26, 2014
    Assignee: Stanley Electric Co., Ltd.
    Inventors: Sho Iwayama, Masahiko Moteki
  • Patent number: 8803126
    Abstract: A solid-state imaging device includes a first electrode, a second electrode disposed opposing to the first electrode, and a photoelectric conversion layer, which is disposed between the first electrode and the second electrode and in which narrow gap semiconductor quantum dots are dispersed in a conductive layer, wherein one electrode of the first electrode and the second electrode is formed from a transparent electrode and the other electrode is formed from a metal electrode or a transparent electrode.
    Type: Grant
    Filed: August 22, 2013
    Date of Patent: August 12, 2014
    Assignee: Sony Corporation
    Inventor: Atsushi Toda
  • Patent number: 8803128
    Abstract: A composite material is described. The composite material comprises semiconductor nanocrystals, and organic molecules that passivate the surfaces of the semiconductor nanocrystals. One or more properties of the organic molecules facilitate the transfer of charge between the semiconductor nanocrystals. A semiconductor material is described that comprises p-type semiconductor material including semiconductor nanocrystals. At least one property of the semiconductor material results in a mobility of electrons in the semiconductor material being greater than or equal to a mobility of holes. A semiconductor material is described that comprises n-type semiconductor material including semiconductor nanocrystals. At least one property of the semiconductor material results in a mobility of holes in the semiconductor material being greater than or equal to a mobility of electrons.
    Type: Grant
    Filed: September 8, 2011
    Date of Patent: August 12, 2014
    Assignee: InVisage Technologies, Inc.
    Inventors: Edward Hartley Sargent, Ghada Koleilat, Larissa Levina
  • Patent number: 8759816
    Abstract: A composite material is described. The composite material comprises semiconductor nanocrystals, and organic molecules that passivate the surfaces of the semiconductor nanocrystals. One or more properties of the organic molecules facilitate the transfer of charge between the semiconductor nanocrystals. A semiconductor material is described that comprises p-type semiconductor material including semiconductor nanocrystals. At least one property of the semiconductor material results in a mobility of electrons in the semiconductor material being greater than or equal to a mobility of holes. A semiconductor material is described that comprises n-type semiconductor material including semiconductor nanocrystals. At least one property of the semiconductor material results in a mobility of holes in the semiconductor material being greater than or equal to a mobility of electrons.
    Type: Grant
    Filed: September 16, 2011
    Date of Patent: June 24, 2014
    Assignee: InVisage Technologies, Inc.
    Inventors: Edward Hartley Sargent, Keith William Johnston, Andras Geza Pattantyus-Abraham, Jason Paul Clifford
  • Patent number: 8742399
    Abstract: A quantum dot, which is an ultrafine grain, has a core-shell structure having a core portion and a shell portion protecting the core portion. The surface of the shell portion is covered with two kinds of surfactants, a hole-transporting surfactant and an electron-transporting surfactant, which are concurrently present. Moreover, the hole-transporting surfactant has a HOMO level which tunneling-resonates with the valence band of the quantum dot and the electron-transporting surfactant has a LUMO level which tunneling-resonates with the transfer band of the quantum dot. Thus, a nanograin material which has good carrier transport efficiency and is suitable for use in a photoelectric conversion device is achieved.
    Type: Grant
    Filed: March 26, 2012
    Date of Patent: June 3, 2014
    Assignee: Murata Manufacturing Co., Ltd.
    Inventor: Koji Murayama
  • Patent number: 8735202
    Abstract: A monolithic, multi-bandgap, tandem solar photovoltaic converter has at least one, and preferably at least two, subcells grown lattice-matched on a substrate with a bandgap in medium to high energy portions of the solar spectrum and at least one subcell grown lattice-mismatched to the substrate with a bandgap in the low energy portion of the solar spectrum, for example, about 1 eV.
    Type: Grant
    Filed: September 23, 2011
    Date of Patent: May 27, 2014
    Assignee: Alliance for Sustainable Energy, LLC
    Inventor: Mark W. Wanlass
  • Patent number: 8729527
    Abstract: A light-receiving element includes a group III-V compound semiconductor stacked structure that includes an absorption layer having a pn-junction therein. The stacked structure is formed on a group III-V compound semiconductor substrate. The absorption layer has a multiquantum well structure composed of group III-V compound semiconductors, and the pn-junction is formed by selectively diffusing an impurity element into the absorption layer. A diffusion concentration distribution control layer composed of a III-V group semiconductor is disposed in contact with the absorption layer on a side of the absorption layer opposite the side adjacent to the group III-V compound semiconductor substrate. The bandgap energy of the diffusion concentration distribution control layer is smaller than that of the group III-V compound semiconductor substrate. The concentration of the impurity element selectively diffused in the diffusion concentration distribution control layer is 5×1016/cm3 or less toward the absorption layer.
    Type: Grant
    Filed: April 19, 2012
    Date of Patent: May 20, 2014
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Yasuhiro Iguchi, Kohei Miura, Hiroshi Inada, Youichi Nagai
  • Patent number: 8703526
    Abstract: A method of fabricating a transparent electrode for use in a quantum dot sensitized solar cell, and a quantum dot sensitized solar cell fabricated according to the method are provided.
    Type: Grant
    Filed: December 15, 2010
    Date of Patent: April 22, 2014
    Assignee: Korea Institute of Science and Technology
    Inventors: Jaehoon Kim, Byoung Koun Min, Jae-Duck Kim, Jong Min Park, Wonho Jang
  • Patent number: 8643058
    Abstract: An electro-optical device can include a plurality of nanocrystals positioned between a first electrode and a second electrode. The nanocrystal and at least one electrode can have a band gap offset sufficient to inject a charge carrier from the first electrode or second electrode into the nanocrystal. The device can be a secondary photoconductor.
    Type: Grant
    Filed: July 31, 2007
    Date of Patent: February 4, 2014
    Assignee: Massachusetts Institute of Technology
    Inventors: Moungi Bawendi, Venda J. Porter, Marc Kastner, Tamar Mentzel
  • Publication number: 20140014902
    Abstract: A method for manufacturing a photodiode including the steps of providing a substrate, solution depositing a quantum nanomaterial layer onto the substrate, the quantum nanomaterial layer including a number of quantum nanomaterials having a ligand coating, and applying a thin-film oxide layer over the quantum nanomaterial layer.
    Type: Application
    Filed: July 16, 2012
    Publication date: January 16, 2014
    Applicant: The Boeing Company
    Inventors: Larken E. Euliss, G. Michael Granger, Keith J. Davis, Nicole L. Abueg, Peter D. Brewer, Brett Nosho
  • Patent number: 8552415
    Abstract: A solid-state imaging device includes a first electrode, a second electrode disposed opposing to the first electrode, and a photoelectric conversion layer, which is disposed between the first electrode and the second electrode and in which narrow gap semiconductor quantum dots are dispersed in a conductive layer, wherein one electrode of the first electrode and the second electrode is formed from a transparent electrode and the other electrode is formed from a metal electrode or a transparent electrode.
    Type: Grant
    Filed: January 25, 2010
    Date of Patent: October 8, 2013
    Assignee: Sony Corporation
    Inventor: Atsushi Toda
  • Patent number: 8492746
    Abstract: A light emitting diode (LED) die includes a wavelength conversion layer having a base material, and a plurality of particles embedded in the base material including wavelength conversion particles, and reflective particles. A method for fabricating light emitting diode (LED) dice includes the steps of mixing the wavelength conversion particles in the base material to a first weight percentage, mixing the reflective particles in the base material to a second weight percentage, curing the base material to form a wavelength conversion layer having a selected thickness, and attaching the wavelength conversion layer to a die.
    Type: Grant
    Filed: May 4, 2012
    Date of Patent: July 23, 2013
    Assignee: SemiLEDS Optoelectronics Co., Ltd.
    Inventor: Jui-Kang Yen
  • Publication number: 20130175500
    Abstract: A transmissive light modulator including a first reflection layer; a first active layer, arranged on the first reflection layer and including a plurality of quantum well layers and a plurality of barrier layers; a second reflection layer arranged on the first active layer; a second active layer, arranged on the second reflection layer and including a plurality of quantum well layers and a plurality of barrier layers; and a third reflection layer arranged on the second active layer, wherein the first reflection layer and the third reflection layer are each doped with a first type dopant, and the second reflection layer is doped with a second type dopant, which is electrically opposite to the first type dopant.
    Type: Application
    Filed: September 14, 2012
    Publication date: July 11, 2013
    Applicants: GWANGJU INSTITUTE OF SCIENCE AND TECHNOLOGY, SAMSUNG ELECTRONICS CO., LTD.
    Inventors: Yong-chul CHO, Yong-tak LEE, Jang-woo YOU, Byung-hoon NA, Yong-hwa PARK, Chang-young PARK, Hee-ju CHIO, Gun-wu JU
  • Patent number: 8461571
    Abstract: In accordance with an example embodiment of the present invention, an apparatus including a nanopillar and a graphene film, the graphene film being in contact with a first end of the nanopillar, wherein the nanopillar includes a metal, the contact being configured to form an intrinsic field region in the graphene film, and wherein the apparatus is configured to generate a photocurrent from a photogenerated charge carrier in the intrinsic field region.
    Type: Grant
    Filed: June 29, 2011
    Date of Patent: June 11, 2013
    Assignee: Nokia Corporation
    Inventor: Alan Colli
  • Patent number: 8461570
    Abstract: A method for manufacturing a semiconductor device, by which a multiple quantum well structure having a large number of pairs can be efficiently grown while maintaining good crystalline quality, and the semiconductor device, are provided. The semiconductor device manufacturing method of the present invention includes a step of forming a multiple quantum well structure 3 having 50 or more pairs of group III-V compound semiconductor quantum wells. In the step of forming the multiple quantum well structure 3, the multiple quantum well structure is formed by metal-organic vapor phase epitaxy using only metal-organic sources (all metal-organic source MOVPE).
    Type: Grant
    Filed: July 7, 2010
    Date of Patent: June 11, 2013
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Kei Fujii, Takashi Ishizuka, Katsushi Akita, Youichi Nagai, Tatsuya Tanabe
  • Publication number: 20130107344
    Abstract: A microcavity-controlled two-dimensional carbon lattice structure device selectively modifies to reflect or to transmit, or emits, or absorbs, electromagnetic radiation depending on the wavelength of the electromagnetic radiation. The microcavity-controlled two-dimensional carbon lattice structure device employs a graphene layer or at least one carbon nanotube located within an optical center of a microcavity defined by a pair of partial mirrors that partially reflect electromagnetic radiation. The spacing between the mirror determines the efficiency of elastic and inelastic scattering of electromagnetic radiation inside the microcavity, and hence, determines a resonance wavelength of electronic radiation that is coupled to the microcavity. The resonance wavelength is tunable by selecting the dimensional and material parameters of the microcavity. The process for manufacturing this device is compatible with standard complementary metal oxide semiconductor (CMOS) manufacturing processes.
    Type: Application
    Filed: October 31, 2011
    Publication date: May 2, 2013
    Applicants: International Business Machines Corporation, Karlsruher Institut fuer Technologie
    Inventors: Phaedon Avouris, Mathias B. Steiner, Michael Engel, Ralph Krupke, Andrea C. Ferrari, Antonio Lombardo
  • Patent number: 8431928
    Abstract: Provided herein are PIN structures including a layer of amorphous n-type silicon, a layer of intrinsic GaAs disposed over the layer of amorphous n-type silicon, and a layer of amorphous p-type silicon disposed over the layer of intrinsic GaAs. The layer of intrinsic GaAs may be engineered by the disclosed methods to exhibit a variety of structural properties that enhance light absorption and charge carrier mobility, including oriented polycrystalline intrinsic GaAs, embedded particles of intrinsic GaAs, and textured surfaces. Also provided are devices incorporating the PIN structures, including photovoltaic devices.
    Type: Grant
    Filed: December 15, 2011
    Date of Patent: April 30, 2013
    Assignee: The University of Utah Research Foundation
    Inventors: Ashutosh Tiwari, Makarand Karmarkar, Nathan Wheeler Gray
  • Publication number: 20130092222
    Abstract: A device includes a generally planar substrate and a plurality of light absorbing elements extending outwardly from the substrate. Each of the light absorbing elements includes a doped outer shell, an inner core disposed inside the outer shell and a two-dimensional electron gas sheet extending and confined between the outer shell and the inner core, with a concentric cylinder of two-dimensional electron or hole gas produced in the junction between the outer shell and the inner core.
    Type: Application
    Filed: October 15, 2012
    Publication date: April 18, 2013
    Applicant: NANOGRASS SOLAR LLC
    Inventor: NanoGrass Solar LLC
  • Patent number: 8415192
    Abstract: A composite material is described. The composite material comprises semiconductor nanocrystals, and organic molecules that passivate the surfaces of the semiconductor nanocrystals. One or more properties of the organic molecules facilitate the transfer of charge between the semiconductor nanocrystals. A semiconductor material is described that comprises p-type semiconductor material including semiconductor nanocrystals. At least one property of the semiconductor material results in a mobility of electrons in the semiconductor material being greater than or equal to a mobility of holes. A semiconductor material is described that comprises n-type semiconductor material including semiconductor nanocrystals. At least one property of the semiconductor material results in a mobility of holes in the semiconductor material being greater than or equal to a mobility of electrons.
    Type: Grant
    Filed: September 16, 2011
    Date of Patent: April 9, 2013
    Assignee: InVisage Technologies, Inc.
    Inventors: Edward Hartley Sargent, Jiang Tang
  • Publication number: 20130075694
    Abstract: Processes for forming quantum well structures which are characterized by controllable nitride content are provided, as well as superlattice structures, optical devices and optical communication systems based thereon.
    Type: Application
    Filed: October 22, 2012
    Publication date: March 28, 2013
    Applicant: Technion Research & Development Foundation Ltd.
    Inventor: Technion Research & Development Foundation Ltd
  • Publication number: 20130068286
    Abstract: Nanowire-based photovoltaic energy conversion devices and related fabrication methods therefor are described. A plurality of photovoltaic (PV) nanowires extend outwardly from a surface layer of a substrate, each PV nanowire having a root end near the substrate surface layer and a tip end opposite the root end. For one preferred embodiment, a canopy-style tip-side electrode layer contacts the tip ends of the PV nanowires and is separated from the substrate surface layer by an air gap layer, the PV nanowires being disposed within the air gap layer. For another preferred embodiment, a tip-side electrode layer is disposed upon a layer of optically transparent, electrically insulating solid filler material that laterally surrounds the PV nanowires along a portion of their lengths, wherein an air gap is disposed between the solid filler layer and the substrate surface layer. Methods for fabricating the nanowire-based photovoltaic energy conversion devices are also described.
    Type: Application
    Filed: August 23, 2010
    Publication date: March 21, 2013
    Inventors: Shih-Ping Wang, Nobuhiko Kobayashi, Yu-Min Houng
  • Publication number: 20130062593
    Abstract: Frontside-illuminated barrier infrared photodetector devices and methods of fabrication are disclosed. In one embodiment, a frontside-illuminated barrier infrared photodetector includes a transparent carrier substrate, and a plurality of pixels. Each pixel of the plurality of pixels includes an absorber layer, a barrier layer on the absorber layer, a collector layer on the barrier layer, and a backside electrical contact coupled to the absorber layer. Each pixel has a frontside and a backside. The absorber layer and the barrier layer are non-continuous across the plurality of pixels, and the barrier layer of each pixel is closer to a scene than the absorber layer of each pixel. A plurality of frontside common electrical contacts is coupled to the frontside of the plurality of pixels, wherein the frontside of the plurality of pixels and the plurality of frontside common electrical contacts are bonded to the transparent carrier substrate.
    Type: Application
    Filed: September 13, 2012
    Publication date: March 14, 2013
    Applicant: L-3 Communications Cincinnati Electronics Corporation
    Inventors: Robert A. Jones, David Forrai, Richard L. Rawe, JR.
  • Patent number: 8390004
    Abstract: A light-emitting structure includes a p-doped region for injecting holes and an n-doped region for injecting electrons. At least one InGaN quantum well of a first type and at least one InGaN quantum well of a second type are arranged between the n-doped region and the p-doped region. The InGaN quantum well of the second type has a higher indium content than the InGaN quantum well of the first type.
    Type: Grant
    Filed: August 25, 2008
    Date of Patent: March 5, 2013
    Assignee: OSRAM Opto Semiconductors GmbH
    Inventors: Adrian Stefan Avramescu, Hans-Juergen Lugauer, Matthias Peter, Stephan Miller
  • Publication number: 20130049569
    Abstract: Wavelength converters, including polarization-enhanced carrier capture converters, for solid state lighting devices, and associated systems and methods are disclosed. A solid state radiative semiconductor structure in accordance with a particular embodiment includes a first region having a first value of a material characteristic and being positioned to receive radiation at a first wavelength. The structure can further include a second region positioned adjacent to the first region to emit radiation at a second wavelength different than the first wavelength. The second region has a second value of the material characteristic that is different than the first value, with the first and second values of the characteristic forming a potential gradient to drive electrons, holes, or both electrons and holes in the radiative structure from the first region to the second region. In a further particular embodiment, the material characteristic includes material polarization.
    Type: Application
    Filed: August 23, 2011
    Publication date: February 28, 2013
    Applicant: MICRON TECHNOLOGY, INC.
    Inventors: Martin F. Schubert, Vladimir Odnoblyudov
  • Publication number: 20130048940
    Abstract: Solid state radiation transducer (SSRT) assemblies and method for making SSRT assemblies. In one embodiment, a SSRT assembly comprises a first substrate having an epitaxial growth material and a radiation transducer on the first substrate. The radiation transducer can have a first semiconductor material grown on the first substrate, a second semiconductor material, and an active region between the first and second semiconductor materials. The SSRT can also have a first contact electrically coupled to the first semiconductor material and a second contact electrically coupled to the second semiconductor material. The first substrate has an opening through which radiation can pass to and/or from the first semiconductor material.
    Type: Application
    Filed: August 26, 2011
    Publication date: February 28, 2013
    Applicant: MICRON TECHNOLOGY, INC.
    Inventors: Scott E. Sills, Anton J. De Villiers
  • Patent number: 8384064
    Abstract: An electroluminescent device comprising a pair of electrodes, and an electroluminescent layer containing at least a luminescent layer, situated between the electrodes. The luminescent layer has a matrix material containing at least one organic compound, and quantum dots whose surfaces are protected by a protective material and that are dispersed in the matrix material. The protective material contains a first protective material. The absolute value of the ionization potential Ip(h), the absolute value of the electron affinity Ea(h), and the band gap Eg(h) of the first protective material, the absolute value of the ionization potential Ip(m), the absolute value of the electron affinity Ea(m), and the band gap Eg(m) of the organic compound, and the band gap Eg(q) of the quantum dots fulfill all of the conditions (A) to (C): (A) Ip(h)<Ip(m)+0.1 eV, (B) Ea(h)>Ea(m)?0.1 eV, and (C) Eg(q)<Eg(h)<Eg(m).
    Type: Grant
    Filed: September 26, 2008
    Date of Patent: February 26, 2013
    Assignee: Dai Nippon Printing Co., Ltd.
    Inventors: Tomonori Akai, Yasuhiro Iizumi
  • Publication number: 20130045383
    Abstract: An array of titanium dioxide nanostructures for solar energy utilization includes a plurality of nanotubes, each nanotube including an outer layer coaxial with an inner layer, where the inner layer comprises p-type titanium dioxide and the outer layer comprises n-type titanium dioxide. An interface between the inner layer and the outer layer defines a p-n junction.
    Type: Application
    Filed: August 19, 2011
    Publication date: February 21, 2013
    Inventors: Xiaofeng Qiu, Mariappan Parans Paranthaman, Miaofang Chi, Ilia N. Ivanov, Zhenyu Zhang
  • Publication number: 20130032782
    Abstract: The invention comprises an optoelectronic platform with a carbon-based conduction layer and a layer of colloidal quantum dots on top as light absorbing material. Photoconductive gain on the order of 106 is possible, while maintaining de operating voltage low. The platform can be used as a transistor.
    Type: Application
    Filed: August 1, 2012
    Publication date: February 7, 2013
    Inventors: KONSTANTATOS Gerasimos, KOPPENS Frank
  • Publication number: 20130032780
    Abstract: A photodiode and the like capable of preventing the responsivity on the short wavelength side from deteriorating while totally improving the responsivity in a type II MQW structure, is provided. The photodiode is formed on a group III-V compound semiconductor substrate 1, and includes a pixel P. The photodiode includes an absorption layer 3 of a type II MQW structure, which is located on the substrate 1. The MQW structure includes fifty or more pairs of two different types of group III-V compound semiconductor layers 3a and 3b. The thickness of one of the two different types of group III-V compound semiconductor layers, which layer 3a has a higher potential of a valence band, is thinner than the thickness of the other layer 3b.
    Type: Application
    Filed: September 28, 2011
    Publication date: February 7, 2013
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Kei Fujii, Takashi Ishizuka, Katsushi Akita, Yasuhiro Iguchi, Hiroshi Inada, Youichi Nagai
  • Patent number: 8368051
    Abstract: An infrared detector having a hole barrier region adjacent to one side of an absorber region, an electron barrier region adjacent to the other side of the absorber region, and a semiconductor adjacent to the electron barrier.
    Type: Grant
    Filed: July 10, 2009
    Date of Patent: February 5, 2013
    Assignee: California Institute of Technology
    Inventors: David Z. Ting, Sumith V. Bandara, Cory J. Hill, Sarath D. Gunapala
  • Publication number: 20130019930
    Abstract: A method of forming an optoelectronic device. The method includes providing a deposition surface and contacting the deposition surface with a ligand exchange chemical and contacting the deposition surface with a quantum dot (QD) colloid. This initial process is repeated over one or more cycles to form an initial QD film on the deposition surface. The method further includes subsequently contacting the QD film with a secondary treatment chemical and optionally contacting the surface with additional QDs to form an enhanced QD layer exhibiting multiple exciton generation (MEG) upon absorption of high energy photons by the QD active layer. Devices having an enhanced QD active layer as described above are also disclosed.
    Type: Application
    Filed: July 20, 2011
    Publication date: January 24, 2013
    Applicant: Alliance for Sustainable Energy, LLC
    Inventors: Octavi Escala Semonin, Joseph M. Luther, Matthew C. Beard, Hsiang-Yu Chen
  • Publication number: 20130001514
    Abstract: In accordance with an example embodiment of the present invention, an apparatus including a nanopillar and a graphene film, the graphene film being in contact with a first end of the nanopillar, wherein the nanopillar includes a metal, the contact being configured to form an intrinsic field region in the graphene film, and wherein the apparatus is configured to generate a photocurrent from a photogenerated charge carrier in the intrinsic field region.
    Type: Application
    Filed: June 29, 2011
    Publication date: January 3, 2013
    Inventor: Alan COLLI
  • Publication number: 20120326124
    Abstract: A method of fabricating a frontside-illuminated inverted quantum well infrared photodetector may include providing a quantum well wafer having a bulk substrate layer and a quantum material layer, wherein the quantum material layer includes a plurality of alternating quantum well layers and barrier layers epitaxially grown on the bulk substrate layer. The method further includes applying at least one frontside common electrical contact to a frontside of the quantum well wafer, bonding a transparent substrate to the frontside of the quantum well wafer, thinning the bulk substrate layer of the quantum well wafer, and etching the quantum material layer to form quantum well facets that define at least one pyramidal quantum well stack. A backside electrical contact may be applied to the pyramidal quantum well stack. In one embodiment, a plurality of quantum well stacks is bonded to a read-out integrated circuit of a focal plane array.
    Type: Application
    Filed: September 6, 2012
    Publication date: December 27, 2012
    Applicant: L-3 Communications Cincinnati Electronics Corporation
    Inventors: David Forrai, Darrel Endres, Robert Jones, Michael James Garter
  • Patent number: 8334157
    Abstract: A method of manufacturing a semiconductor device comprises depositing a semiconductor layer over a semiconductor surface having at least one first region with a first (average surface lattice) parameter value and at least one second region having a second parameter value different from the first. The semiconductor layer is deposited to a thickness so self-organized islands form over both the first and second regions. The difference in the parameter value means the islands over the first region have a first average parameter value and the islands over the second region have a second average parameter value different from the first. A capping layer is deposited over islands and has a greater forbidden bandgap than the islands whereby the islands form quantum dots, which have different properties over the first and second regions due to difference(s) between the first and second region islands.
    Type: Grant
    Filed: August 12, 2008
    Date of Patent: December 18, 2012
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Tim Michael Smeeton, Katherine Louise Smith, Mathieu Xavier Sénès, Stewart Edward Hooper
  • Publication number: 20120298957
    Abstract: The present invention provides a light receiving element array etc., having a high light-reception sensitivity in the near-infrared region, an optical sensor device, and a method for producing the light receiving element array. A light receiving element array 55 includes an n-type buffer layer 2 disposed on an InP substrate 1, an absorption layer 3 having a type-II MQW, a contact layer 5 disposed on the absorption layer, and a p-type region extending to the n-type buffer layer 2 through the absorption layer 3, wherein the p-type region formed by selective diffusion is separated from the p-type region of an adjacent light receiving element by a region that is not subjected to selective diffusion, and, in the n-type buffer layer, a p-n junction 15 is formed on a crossed face of a p-type carrier concentration of the p-type region and an n-type carrier concentration of the buffer layer.
    Type: Application
    Filed: March 10, 2011
    Publication date: November 29, 2012
    Applicant: Sumitomo Electric Industries, Ltd.
    Inventors: Yasuhiro Iguchi, Hiroshi Inada, Youichi Nagai, Hideaki Nakahata, Katsushi Akita, Takashi Ishizuka, Kei Fujii
  • Patent number: 8309391
    Abstract: A method for manufacturing an array-type nanotube layer for a thin-film solar cell comprises the steps of: preparing an isotropic Si-substrate; sputtering a metal Ti layer onto the isotropic Si-substrate; heat-treating the Ti-coated Si-substrate in a vacuum heat-treatment environment; annealing the Ti-coated Si-substrate in an annealing heat-treatment environment to produce an intermediate-phase metal Ti layer; anodizing the intermediate-phase metal Ti layer so as to transform the intermediate-phase metal Ti layer into an array-type nanotube layer for the solar cell; and finally applying a reverse voltage to separate the array-type nanotube layer from the isotropic Si-substrate.
    Type: Grant
    Filed: February 23, 2011
    Date of Patent: November 13, 2012
    Inventor: Nan-Hui Yeh
  • Publication number: 20120280208
    Abstract: This invention describes a field-effect transistor in which the channel is formed in an array of quantum dots. In one embodiment the quantum dots are cladded with a thin layer serving as an energy barrier. The quantum dot channel (QDC) may consist of one or more layers of cladded dots. These dots are realized on a single or polycrystalline substrate. When QDC FETs are realized on polycrystalline or nanocrystalline thin films they may yield higher mobility than in conventional nano- or microcrystalline thin films. These FETs can be used as thin film transistors (TFTs) in a variety of applications. In another embodiment QDC-FETs are combined with: (a) coupled quantum well SWS channels, (b) quantum dot gate 3-state like FETs, and (c) quantum dot gate nonvolatile memories.
    Type: Application
    Filed: May 7, 2012
    Publication date: November 8, 2012
    Inventor: Faquir Chand Jain