In Different Semiconductor Regions (e.g., Heterojunctions) (epo) Patents (Class 257/E29.091)
  • Publication number: 20100230684
    Abstract: A semiconductor device includes a channel layer, an electron-supplying layer provided on the channel layer, a cap layer provided on the electron-supplying layer and creating lattice match with the channel layer, and ohmic electrodes provided on the cap layer. The cap layer has a composition of (InyAl1-y)zGa1-zN (0?y?1, 0?z?1). The z for such cap layer monotonically decreases as being farther away from the electron-supplying layer.
    Type: Application
    Filed: May 7, 2007
    Publication date: September 16, 2010
    Applicant: NEC CORPORATION
    Inventors: Yasuhiro Okamoto, Yuji Ando, Takashi Inoue, Tatsuo Nakayama, Hironobu Miyamoto
  • Publication number: 20100230687
    Abstract: In a group III nitride hetero junction transistor 11a, a second AlY1InY2Ga1-Y1-Y2N layer 15 forms a hetero junction 21 with a first AlX1InX2Ga1-X1-X2N layer 13a. A first electrode 17 forms a Schottky junction with the first AlX1InX2Ga1-X1-X2N layer 13a. The first AlX1InX2Ga1-X1-X2N layer 13a and the second AlY1InY2Ga1-Y1-Y2N layer 15 are provided over a substrate 23. The electrodes 17a, 18a, and 19a include a source electrode, a gate electrode, and a drain electrode, respectively. The carbon concentration NC13 in the first AlX1InX2Ga1-X1-X2N layer 13a is less than 1×1017 cm?3. The dislocation density D in the second AlY1InY2Ga1-Y1-Y2N layer 15 is 1×108 cm?2. The hetero junction 21 generates a two-dimensional electron gas layer 25. These provide a low-loss gallium nitride based electronic device.
    Type: Application
    Filed: October 28, 2008
    Publication date: September 16, 2010
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Shin Hashimoto, Tatsuya Tanabe
  • Publication number: 20100230690
    Abstract: A group III nitride semiconductor device having a gallium nitride based semiconductor film with an excellent surface morphology is provided. A group III nitride optical semiconductor device 11a includes a group III nitride semiconductor supporting base 13, a GaN based semiconductor region 15, an active layer active layer 17, and a GaN semiconductor region 19. The primary surface 13a of the group III nitride semiconductor supporting base 13 is not any polar plane, and forms a finite angle with a reference plane Sc that is orthogonal to a reference axis Cx extending in the direction of a c-axis of the group III nitride semiconductor. The GaN based semiconductor region 15 is grown on the semipolar primary surface 13a. A GaN based semiconductor layer 21 of the GaN based semiconductor region 15 is, for example, an n-type GaN based semiconductor, and the n-type GaN based semiconductor is doped with silicon.
    Type: Application
    Filed: February 26, 2010
    Publication date: September 16, 2010
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Takashi KYONO, Yusuke YOSHIZUMI, Yohei ENYA, Katsushi AKITA, Masaki UENO, Takamichi SUMITOMO, Takao NAKAMURA
  • Publication number: 20100220761
    Abstract: A gallium nitride-based semiconductor optical device is provided that includes an indium-containing gallium nitride-based semiconductor layer that exhibit low piezoelectric effect and high crystal quality. The gallium nitride-based semiconductor optical device 11a includes a GaN support base 13, a GaN-based semiconductor region 15, and well layers 19. A primary surface 13a tilts from a surface orthogonal to a reference axis that extends in a direction from one crystal axis of the m-axis and the a-axis of GaN toward the other crystal axis. The tilt angle AOFF is equal to the angle defined by a vector VM and a vector VN. The inclination of the primary surface is shown by a typical m-plane SM and m-axis vector VM. The GaN-based semiconductor region 15 is provided on the primary surface 13a. In the well layers 19 in an active layer 17, both the m-plane and the a-plane of the well layers 19 tilt from a normal axis AN of the primary surface 13a. The indium content of the well layers 19 is 0.1 or more.
    Type: Application
    Filed: March 2, 2010
    Publication date: September 2, 2010
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Yohei ENYA, Yusuke YOSHIZUMI, Hideki OSADA, Keiji ISHIBASHI, Katsushi AKITA, Masaki UENO
  • Publication number: 20100219449
    Abstract: The disclosure relates to a zero-bias heterojunction diode detector with varying impedance. The detector includes a substrate supporting a Schottky structure and an Ohmic contact layer. A metallic contact layer is formed over the Ohmic layer. The Schottky structure comprises a plurality of barrier layers and each of the plurality of barriers layers includes a first material and a second material. In one embodiment, the composition percentage of the second material in each of the barrier layers increases among the plurality of barrier layers from the substrate to the metal layer in order to provide a graded periodicity for the Schottky structure.
    Type: Application
    Filed: February 27, 2009
    Publication date: September 2, 2010
    Applicant: TELEDYNE SCIENTIFIC & IMAGING, LLC
    Inventors: Hooman Kazemi, Chanh Nguyen, Berinder Brar
  • Publication number: 20100213513
    Abstract: A hyperabrupt diode structure includes a substrate formed from a low-ohmic contact material, a graded semiconductor layer comprising gallium arsenide, an offset layer comprising indium gallium phosphide over the graded semiconductor layer, a contact layer comprising gallium arsenide over the offset layer, a first electrical contact on the substrate, the first electrical contact forming a cathode of the hyperabrupt diode structure, and a second electrical contact over the contact layer, the second electrical contact forming an anode of the hyperabrupt diode structure.
    Type: Application
    Filed: February 26, 2009
    Publication date: August 26, 2010
    Applicant: Skyworks Solutions, Inc.
    Inventors: Peter J. Zampardi, HsiangChih Sun
  • Patent number: 7781805
    Abstract: A memory array having memory cells comprising a diode and an antifuse can be made smaller and programmed at lower voltage by using an antifuse material having a higher dielectric constant and a higher acceleration factor than those of silicon dioxide, and by using a diode having a lower band gap than that of silicon. Such memory arrays can be made to have long operating lifetimes by using the high acceleration factor and lower band gap materials. Antifuse materials having dielectric constants between 5 and 27, for example, hafnium silicon oxynitride or hafnium silicon oxide, are particularly effective. Diode materials with band gaps lower than that of silicon, such as germanium or a silicon-germanium alloy, are particularly effective.
    Type: Grant
    Filed: February 6, 2009
    Date of Patent: August 24, 2010
    Assignee: SanDisk 3D LLC
    Inventors: Xiaoyu Yang, Roy E. Scheurelein, Feng Li, Albert T. Meeks
  • Publication number: 20100207167
    Abstract: A semiconductor epitaxial substrate includes: a single crystal substrate; an AlN layer epitaxially grown on the single crystal substrate; and a nitride semiconductor layer epitaxially grown on the AlN layer, wherein an interface between the AlN layer and nitride semiconductor layer has a larger roughness than an interface between the single crystal substrate and AlN layer, and a skewness of the upper surface of the AlN layer is positive.
    Type: Application
    Filed: May 3, 2010
    Publication date: August 19, 2010
    Applicants: FUJITSU LIMITED, HITACHI CABLE, LTD.
    Inventors: Kenji IMANISHI, Toshihide KIKKAWA, Takeshi TANAKA, Yoshihiko MORIYA, Yohei OTOKI
  • Publication number: 20100207124
    Abstract: A semiconductor epitaxial substrate includes: a single crystal substrate; an AlN layer epitaxially grown on the single crystal substrate; and a nitride semiconductor layer epitaxially grown on the AlN layer, wherein an interface between the AlN layer and nitride semiconductor layer has a larger roughness than an interface between the single crystal substrate and AlN layer, and a skewness of the upper surface of the AlN layer is positive.
    Type: Application
    Filed: May 3, 2010
    Publication date: August 19, 2010
    Applicants: FUJITSU LIMITED, HITACHI CABLE, LTD.
    Inventors: Kenji IMANISHI, Toshihide KIKKAWA, Takeshi TANAKA, Yoshihiko MORIYA, Yohei OTOKI
  • Publication number: 20100193843
    Abstract: A manufacture method of a multilayer structure having a non-polar a-plane {11-22} III-nitride layer includes forming a nucleation layer on a r-plane substrate, wherein the nucleation layer is composed of multiple nitride layers; and forming a non-polar a-plane {11-20} III-nitride layer on the nucleation layer. The nucleation layer features reduced stress, reduced phase difference of lattice, blocked elongation of dislocation, and reduced density of dislocation. Thus, the non-polar a-plane {11-20} III-nitride layer with flat surface can be formed.
    Type: Application
    Filed: May 19, 2009
    Publication date: August 5, 2010
    Applicant: NATIONAL CHIAO TUNG UNIVERSITY
    Inventors: Wei-I Lee, Jenn-Fang Chen, Chen-Hao Chiang
  • Publication number: 20100187544
    Abstract: In one aspect, a method includes fabricating a gallium nitride (GaN) layer with a first diamond layer having a first thermal conductivity and a second diamond layer having a second thermal conductivity greater than the first thermal conductivity. The fabricating includes using a microwave plasma chemical vapor deposition (CVD) process to deposit the second diamond layer onto the first diamond layer.
    Type: Application
    Filed: April 2, 2010
    Publication date: July 29, 2010
    Applicant: Raytheon Company
    Inventors: Ralph Korenstein, Steven D. Bernstein, Stephen J. Pereira
  • Publication number: 20100147370
    Abstract: Embodiments of the invention are provided for a thin film stack containing a plurality of epitaxial stacks disposed on a substrate and a method for forming such a thin film stack. In one embodiment, the epitaxial stack contains a first sacrificial layer disposed over the substrate, a first epitaxial film disposed over the first sacrificial layer, a second sacrificial layer disposed over the first epitaxial film, and a second epitaxial film disposed over the second sacrificial layer. The thin film stack may further contain additional epitaxial films disposed over sacrificial layers. Generally, the epitaxial films contain gallium arsenide alloys and the sacrificial layers contain aluminum arsenide alloys. Methods provide the removal of the epitaxial films from the substrate by etching away the sacrificial layers during an epitaxial lift off (ELO) process. The epitaxial films are useful as photovoltaic cells, laser diodes, or other devices or materials.
    Type: Application
    Filed: December 7, 2009
    Publication date: June 17, 2010
    Applicant: ALTA DEVICES, INC.
    Inventors: Gang He, Andreas Hegedus
  • Publication number: 20100148195
    Abstract: 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 InxGa1-xN nucleation layer on the heated substrate, depositing a semipolar nitride semiconductor thin film on the InxGa1-xN nucleation layer, and cooling the substrate under a nitrogen overpressure.
    Type: Application
    Filed: February 22, 2010
    Publication date: June 17, 2010
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: John F. Kaeding, Dong-Seon Lee, Michael Iza, Troy J. Baker, Hiroshi Sato, Benjamin A. Haskell, James S. Speck, Steven P. DenBaars, Shuji Nakamura
  • Publication number: 20100133547
    Abstract: A semiconductor sensor determines physical and/or chemical properties of a medium, in particular a pH sensor. The semiconductor sensor has an electronic component with a sensitive surface, said component being constructed for its part on the basis of semiconductors with a large band gap (wide-gap semiconductor). The sensitive surface is provided at least in regions with a functional layer sequence which has an ion-sensitive surface. The functional layer sequence has at least one layer which is impermeable at least for the medium and/or the materials or ions to be determined.
    Type: Application
    Filed: August 8, 2006
    Publication date: June 3, 2010
    Inventors: Mike Kunze, Ingo Daumiler
  • Publication number: 20100127275
    Abstract: A GaN-based field effect transistor 101 comprises: a substrate 101; a channel layer 104 comprised of p-type GaN-based semiconductor material formed on the substrate 101; an electron supplying layer 106 formed on said channel layer 104 and comprised of GaN-based semiconductor material which has band gap energy greater than that of said channel layer 104; a gate insulating film 111 formed on a surface of said channel layer which was exposed after a part of said electron supplying layer was removed; a gate electrode 112 formed on said gate insulating film; a source electrode 109 and a drain electrode 110 formed so that said gate electrode 112 positions in between them; and a second insulating film 113 formed on said electron supplying layer, which is a different insulating film from said gate insulating film 111 and has electron collapse decreasing effect.
    Type: Application
    Filed: November 25, 2009
    Publication date: May 27, 2010
    Applicant: FURUKAWA ELECTRIC CO., LTD.
    Inventors: Nomura Takehiko, Sato Yoshihiro, Kambayashi Hiroshi, Kaya Shusuke, Iwami Masayuki, Kato Sadahiro
  • Publication number: 20100123139
    Abstract: An aspect of the present invention inheres in a semiconductor wafer includes a support substrate, a first nitride semiconductor layer, at least an upper surface of which has become monocrystalline, the first semiconductor layer being provided on the support substrate, and a second nitride semiconductor layer containing nitrogen and gallium, the second nitride semiconductor layer being provided on the upper surface of the first nitride semiconductor layer.
    Type: Application
    Filed: November 17, 2009
    Publication date: May 20, 2010
    Applicant: Sanken Electric Co., Ltd.
    Inventor: Ken Sato
  • Publication number: 20100117118
    Abstract: A method for providing a periodic table group III nitrides materials based heterojunction device comprising growing all layers therein by molecular beam epitaxy to result having a crystal defects concentration sufficiently small to allow electron mobilities in the sheet charge region to exceed 1100 cm2/volt-second. The invention includes the heterojunction device provided by this method.
    Type: Application
    Filed: August 7, 2009
    Publication date: May 13, 2010
    Inventors: Amir M. Dabiran, Andrew M. Wowchak
  • Publication number: 20100117094
    Abstract: The present invention provides a gallium nitride type epitaxial crystal, a method for producing the crystal, and a field effect transistor using the crystal. The gallium nitride type epitaxial crystal comprises a base substrate and the following (a) to (e), wherein a connection layer comprising a gallium nitride type crystal is arranged in an opening of the non-gallium nitride type insulating layer to electrically connect the first buffer layer and the p-conductive type semiconductor crystal layer. (a) a gate layer, (b) a high purity first buffer layer containing a channel layer contacting an interface on the base substrate side of the gate layer, (c) a second buffer layer arranged on the base substrate side of the first buffer layer, (d) a non-gallium nitride type insulating layer arranged on the base substrate side of the second buffer layer, and having the opening at a part thereof, and (e) a p-conductive type semiconductor crystal layer arranged on the base substrate side of the insulating layer.
    Type: Application
    Filed: February 7, 2008
    Publication date: May 13, 2010
    Applicant: SUMITOMO CHEMICAL COMPANY, LIMITED
    Inventors: Naohiro Nishikawa, Hiroyuki Sazawa, Masahiko Hata
  • Publication number: 20100109018
    Abstract: A method for fabricating a single crystal, high quality, semi-insulating (SI) gallium nitride (GaN) layer using an AlxGa1-xN blocking layer. A buffer layer is grown on a substrate, the AlxGa1-xN blocking layer is grown on the buffer layer, and a single crystal, high quality, SI-GaN layer is grown on the AlxGa1-xN blocking layer. The AlxGa1-xN blocking layer acts as a diffusion blocking layer that prevents the diffusion of donors from the substrate from reaching the SI-GaN layer. The resulting SI-GaN layer reduces parasitic current flow and parasitic capacitive effects in electronic devices.
    Type: Application
    Filed: November 2, 2009
    Publication date: May 6, 2010
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Zhen Chen, Umesh K. Mishra, Steven P. DenBaars, Shuji Nakamura
  • Patent number: 7705371
    Abstract: A field effect transistor includes a nitride semiconductor layered structure that is formed on a substrate and includes a capping layer made of a compound represented by a general formula of InxAlyGa1-yN (wherein 0<x?1, 0?y <1 and 0<x+y?1). A non-alloy source electrode and a non-alloy drain electrode are formed on the capping layer so as to be spaced from each other.
    Type: Grant
    Filed: April 3, 2007
    Date of Patent: April 27, 2010
    Assignee: Panasonic Corporation
    Inventors: Satoshi Nakazawa, Tetsuzo Ueda
  • Patent number: 7700972
    Abstract: A semiconductor device comprises an AlN layer, a GaN layer, and an AlGaN layer sequentially formed on a semiconductor substrate. A first opening extends through said GaN layer and said AlGaN layer and exposes part of an upper surface of the AlN layer. A second opening extends through the semiconductor substrate and exposes a part of a lower surface of the AlN layer, in a location facing the first opening. A upper electrode is exposed on an upper surface of the AlN layer in the first opening; and a lower electrode is disposed on a lower surface of the AlN layer in the second opening.
    Type: Grant
    Filed: June 20, 2008
    Date of Patent: April 20, 2010
    Assignee: Mitsubishi Electric Corporation
    Inventors: Hideo Takeuchi, Yoshitsugu Yamamoto
  • Publication number: 20100090225
    Abstract: A nitride semiconductor device includes: a main semiconductor region comprising a first nitride semiconductor layer having a first band gap, and a second nitride semiconductor layer having a second band gap larger than the first band gap, a heterojunction being formed between the first nitride semiconductor layer and a the second nitride semiconductor layer such that two-dimensional electron gas layer can be caused inside the first nitride semiconductor layer based on the heterojunction; a source electrode formed on the main semiconductor region; a drain electrode formed on the main semiconductor region and separated from the source electrode; a third nitride semiconductor layer formed on the first nitride semiconductor layer and between the source electrode and the drain electrode; and a gate electrode formed on the third nitride semiconductor layer. The third nitride semiconductor layer has a third band gap smaller than the first band gap.
    Type: Application
    Filed: October 14, 2009
    Publication date: April 15, 2010
    Applicant: SANKEN ELECTRIC CO., LTD.
    Inventor: Ken SATO
  • Publication number: 20100090250
    Abstract: A semiconductor device includes: a semiconductor layer; at least one electrode formed on a semiconductor layer to be in contact with the semiconductor layer; and a passivation film covering the semiconductor layer and at least part of the top surface of the electrode to protect the semiconductor layer and formed of a plurality of sub-films. The passivation film includes a first sub-film made of aluminum nitride.
    Type: Application
    Filed: December 14, 2009
    Publication date: April 15, 2010
    Applicant: PANASONIC CORORATION
    Inventors: Tomohiro MURATA, Hiroaki Ueno, Hidetoshi Ishida, Tetsuzo Ueda, Yasuhiro Uemoto, Tsuyoshi Tanaka, Daisuke Ueda
  • Publication number: 20100072516
    Abstract: A nitride semiconductor device includes an active layer formed between an n-type cladding layer and a p-type cladding layer, and a current confining layer having a conductive area through which a current flows to the active layer. The current confining layer includes a first semiconductor layer, a second semiconductor layer and a third semiconductor layer. The second semiconductor layer is formed on and in contact with the first semiconductor layer and has a smaller lattice constant than that of the first semiconductor layer. The third semiconductor layer is formed on and in contact with the second semiconductor layer and has a lattice constant that is smaller than that of the first semiconductor layer and larger than that of the second semiconductor layer.
    Type: Application
    Filed: September 10, 2009
    Publication date: March 25, 2010
    Inventors: Satoshi TAMURA, Ryo KAJITANI
  • Publication number: 20100065890
    Abstract: A semiconductor substrate, of GaAs with a semiconductor layer sequence applied on top of the substrate. The semiconductor layer sequence comprises a plurality of semiconductor layers of Al1-yGayAs1-xPx with 0?x?1 and 0?y?1. A number of the semiconductor layers respectively comprising a phosphorus component x which is greater than in a neighboring semiconductor layer lying thereunder in the direction of growth of the semiconductor layer sequence. Two semiconductor layers directly preceding the uppermost semiconductor layer of the semiconductor layer sequence have a smaller lattice constant than the uppermost layer.
    Type: Application
    Filed: November 19, 2009
    Publication date: March 18, 2010
    Inventors: Norbert Linder, Günther Grönninger, Peter Heidborn, Klaus Streubel, Siegmar Kugler
  • Publication number: 20100065865
    Abstract: A method of forming a nitride semiconductor through ion implantation and an electronic device including the same are disclosed. In the method, an ion implantation region composed of a line/space pattern is formed on a substrate at an ion implantation dose of more than 1E17 ions/cm2 to 5E18 ions/cm2 or less and an ion implantation energy of 30˜50 keV, and a metal nitride thin film is grown on the substrate by epitaxial lateral overgrowth, thereby decreasing lattice defects in the metal nitride thin film. Thus, the electronic device has improved efficiency.
    Type: Application
    Filed: April 28, 2009
    Publication date: March 18, 2010
    Applicant: Korea University Industrial & Academic Collaboration Foundation
    Inventors: Dong-Jin BYUN, Bum-Joon Kim, Jung-Geun Jhin, Jong-Hyeob Baek
  • Publication number: 20100052016
    Abstract: A method of manufacturing a nitride semiconductor structure includes disposing a semiconductor substrate in a molecular beam epitaxy reactor; growing a wetting layer comprising AlxInyGa(1?(x/y))As(0?x+y?1) or AlxInyGa(1?(x/y))P(0?x+y?1) on the substrate; in-situ annealing the wetting layer; growing a first AlGaInN layer on the wetting layer using plasma activated nitrogen as the source of nitrogen with an additional flux of phosphorous or arsenic; and growing a second AlGaInN layer on the first AlGaInN layer using ammonia as a source of nitrogen.
    Type: Application
    Filed: August 28, 2008
    Publication date: March 4, 2010
    Inventors: Stewart Edward HOOPER, Jonathan Heffernan
  • Publication number: 20100044753
    Abstract: A nitride semiconductor device 2 comprises a nitride semiconductor layer 10. A gate insulating film 16 is formed on the surface of the nitride semiconductor layer 10. The gate insulating film 16 includes a portion composed of an aluminum nitride film 15 and a portion composed of an insulating material 14 that contains at least one of oxygen or silicon. A region W2 of the nitride semiconductor layer 10 facing the aluminum nitride film 15 is included in a region W1 of the nitride semiconductor layer 10 facing a gate electrode 18. The nitride semiconductor device 2 may further comprise a nitride semiconductor lower layer 8. The nitride semiconductor layer 10 may be stacked on the surface of the nitride semiconductor lower layer 8. The nitride semiconductor layer 10 may have a larger band gap than that of the nitride semiconductor lower layer 8 and have a heterojunction formed there between.
    Type: Application
    Filed: August 20, 2009
    Publication date: February 25, 2010
    Inventors: Masahiro SUGIMOTO, Hiroyuki Ueda, Tsutomu Uesugi, Masakazu Kanechika, Tetsu Kachi
  • Publication number: 20100032717
    Abstract: A nitride-based semiconductor device is provided. The nitride-base semiconductor device includes a substrate comprising one or more locally etched regions and a buffer layer comprising one or multiple InAlGaN layers on the substrate. A channel layer includes GaN on the buffer layer. A barrier layer includes one or multiple AlGaN layers on the channel layer.
    Type: Application
    Filed: October 13, 2009
    Publication date: February 11, 2010
    Inventors: Tomas Palacios, Jinwook Chung
  • Publication number: 20100032719
    Abstract: Disclosed are probes for scanning probe microscopy comprising a semiconductor heterostructure and methods of making the probes. The semiconductor heterostructure determines the optical properties of the probe and allows for optical imaging with nanometer resolution.
    Type: Application
    Filed: October 9, 2008
    Publication date: February 11, 2010
    Inventors: Seunghun HONG, Taekyeong KIM
  • Publication number: 20100032683
    Abstract: The GaN-based semiconductor element 20 of the present invention comprises the buffer layer 2 formed on the sapphire (0001) substrate 1, the channel layer 3 comprised of the undoped GaN layer, and the electron supply layer 4 comprised of the undoped AlGaN layer. The buffer layer 2 is comprised of the n-GaN layer having n-type conductivity. The configuration is adopted as the structure to be able to control the electric potential of the buffer layer 2, wherein the source electrode 6 is implanted into the epitaxial layer (the channel layer 3 and the electron supply layer 4) to be formed on the buffer layer 2, and it is extended to the depth reaching the buffer layer 2 for ohmic contacting to the buffer layer 2. It is able to fix the electric potential of the buffer layer 2 comprised of the n-GaN layer for being equal to that of the source electrode 6 because the source electrode 6 is ohmic contacted to the buffer layer 2.
    Type: Application
    Filed: August 4, 2009
    Publication date: February 11, 2010
    Inventors: Nariaki Ikeda, Seikoh Yoshida, Masatoshi Ikeda
  • Publication number: 20100025696
    Abstract: The process according to the present invention is adapted to produce a silicon carbide substrate for microelectronic applications; it comprises the following steps: a) providing a conductive silicon carbide wafer, and b) growing an epitaxial layer of intrinsic silicon carbide on said wafer.
    Type: Application
    Filed: September 19, 2007
    Publication date: February 4, 2010
    Inventors: Giuseppe Abbondanza, Danilo Crippa
  • Publication number: 20100006894
    Abstract: The semiconductor device includes a P-type group III-V nitride semiconductor layer, an N-type group III-V nitride semiconductor layer, and an electrode in contact with both of the P-type group III-V nitride semiconductor layer and the N-type group III-V nitride semiconductor layer. The electrode includes a first electrode portion made of a first conductive material, and a second electrode portion, made of a second conductive material different from the first conductive material, bonded to the first electrode portion. The first electrode portion is in contact with the P-type group III-V nitride semiconductor layer, and the second electrode portion is in contact with the N-type group III-V nitride semiconductor layer.
    Type: Application
    Filed: August 22, 2007
    Publication date: January 14, 2010
    Applicant: ROHM CO., LTD.
    Inventors: Hiroaki Ohta, Hidemi Takasu
  • Publication number: 20100008391
    Abstract: A nitride based semiconductor device includes: an n-type cladding layer; an n-type GaN based guide layer placed on the n-type cladding layer; an active layer placed on the n-type GaN based guide layer; a p-type GaN based guide layer placed on the active layer; an electron block layer placed on the p-type GaN based guide layer; a stress relaxation layer placed on the electron block layer; and a p-type cladding layer placed on the stress relaxation layer, and the nitride based semiconductor device alleviates the stress occurred under the influence of the electron block layer, does not affect light distribution by the electron block layer, reduces threshold current, can suppress the degradation of reliability, can suppress degradation of the emitting end surface of the laser beam, can improve the far field pattern, and is long lasting, and fabrication method of the device is also provided.
    Type: Application
    Filed: March 4, 2009
    Publication date: January 14, 2010
    Applicant: ROHM CO., LTD.
    Inventors: Daisuke Nakagawa, Yoshinori Tanaka, Masahiro Murayama, Takao Fujimori, Shinichi Kohda
  • Patent number: 7646040
    Abstract: A boron phosphide-based semiconductor device having a junction structure of a Group-III nitride semiconductor layer and a boron phosphide layer with excellent device properties is provided. The boron phosphide-based compound semiconductor device has a heterojunction structure comprising a Group-III nitride semiconductor layer and a boron phosphide layer, wherein the surface of the Group-III nitride semiconductor layer has (0.0.0.1.) crystal plane, and the boron phosphide layer is a {111}-boron phosphide layer having a {111} crystal plane stacked on the (0.0.0.1.) crystal plane of the Group-III nitride semiconductor layer in parallel to the (0.0.0.1.) crystal plane.
    Type: Grant
    Filed: November 27, 2003
    Date of Patent: January 12, 2010
    Assignee: Showa Denko K.K.
    Inventor: Takashi Udagawa
  • Patent number: 7638818
    Abstract: A semiconductor device, and particularly a high electron mobility transistor (HEMT), having a plurality of epitaxial layers and experiencing an operating (E) field. A negative ion region in the epitaxial layers to counter the operating (E) field. One method for fabricating a semiconductor device comprises providing a substrate and growing epitaxial layers on the substrate. Negative ions are introduced into the epitaxial layers to form a negative ion region to counter operating electric (E) fields in the semiconductor device. Contacts can be deposited on the epitaxial layers, either before or after formation of the negative ion region.
    Type: Grant
    Filed: July 7, 2006
    Date of Patent: December 29, 2009
    Assignee: Cree, Inc.
    Inventors: Yifeng Wu, Marcia Moore, Tim Wisleder, Primit Parikh
  • Publication number: 20090315075
    Abstract: A semiconductor device is, constituted by: a nitride group semiconductor functional layer which includes a first nitride group semiconductor region, a second nitride group semiconductor region provided on the first nitride group semiconductor region by a hetero junction, and a two-dimensional carrier gas channel near the hetero junction of the first nitride group semiconductor region; a first main electrode and a second main electrode connected to the two-dimensional carrier gas channel by ohmic contact; and a gate electrode disposed between the first main electrode and the second main electrode. The nitride group semiconductor region has different thicknesses between the second main electrode and the gate electrode, and between the first main electrode and the gate electrode.
    Type: Application
    Filed: May 22, 2009
    Publication date: December 24, 2009
    Applicant: Sanken Electric Co., Ltd.
    Inventor: Ken Sato
  • Patent number: 7622791
    Abstract: A III-V group nitride system semiconductor substrate is of a III-V group nitride system single crystal. The III-V group nitride system semiconductor substrate has a flat surface, and a vector made by projecting on a surface of the substrate a normal vector of a low index surface closest to the substrate surface at an arbitrary point in a plane of the substrate is converged on a specific point or a specific region inside or outside the plane of the substrate.
    Type: Grant
    Filed: August 22, 2007
    Date of Patent: November 24, 2009
    Assignee: Hitachi Cable, Ltd.
    Inventor: Masatomo Shibata
  • Publication number: 20090278172
    Abstract: The field effect transistor includes a laminated structure in which a buffer layer, and an electron transporting layer (undoped GaN layer), and an electron supplying layer (undoped AlGaN layer) are laminated in sequence on a sapphire substrate. An npn laminated structure is formed on a source region of the electron supplying layer, and a source electrode is formed on the npn laminated structure. A drain electrode is formed in a drain region of the electron supplying layer, and an insulating film is formed in an opening region formed in the gate region. When a forward voltage greater than a threshold is applied to the gate electrode, an inversion layer is formed and the drain current flows. By changing a thickness and an impurity concentration of the p-type GaN layer, the threshold voltage can be controlled. The electrical field concentration between the gate electrode and the drain electrode is relaxed due to the drift layer, and voltage resistance improves.
    Type: Application
    Filed: March 5, 2009
    Publication date: November 12, 2009
    Inventors: Shusuke Kaya, Seikoh Yoshida, Sadahiro Kato, Takehiko Nomura, Nariaki Ikeda, Masayuki Iwami, Yoshihiro Sato, Hiroshi Kambayashi, Yuki Niiyama, Masatoshi Ikeda
  • Publication number: 20090278171
    Abstract: A high linearity doped-channel FET, comprises a substrate, a buffer layer, a channel layer and a cap layer stacked downwardly thereon. The cap layer has a source region, a drain region with a distance apart from the source region and a gate region formed by removing part of the cap layer between the source region and the drain region. A source electrode and a drain electrode are respectively formed on the source region and the drain region, and a gate electrode is formed on the gate region, wherein the source region and the drain region of the cap layer are respectively provided with an opening for forming a good ohmic contact between the source region and the drain region with the channel layer respectively.
    Type: Application
    Filed: May 9, 2008
    Publication date: November 12, 2009
    Applicant: WIN Semiconductors Corp.
    Inventors: Iris Hsieh, Jeff Yeh, Cheng-Guan Yuan, Yu Chi Wang
  • Publication number: 20090250723
    Abstract: In an electronic device of the present invention a gate Schottky electrode is formed on an active layer constructed of a GaN layer and an AlGaN layer, and a source ohmic electrode and a drain ohmic electrode are further formed on both sides of the gate Schottky electrode on the active layer. A dielectric layer (TiO2 layer) of a stepwise laminate structure is formed on the AlGaN layer so that the electric field distribution between the gate Schottky electrode and the drain ohmic electrode is substantially uniformed. The dielectric constant of TiO2 of the dielectric layer is made higher than the dielectric constant of GaN and AlGaN of the active layer.
    Type: Application
    Filed: June 15, 2009
    Publication date: October 8, 2009
    Inventor: John Kevin Twynam
  • Publication number: 20090236634
    Abstract: A nitride semiconductor epitaxial wafer includes a growth substrate including a surface for growing a nitride semiconductor thereon, a first structure layer formed on the growth substrate, a dislocation propagation direction changing layer formed on the first structure layer for changing a propagation direction of a dislocation propagated in the first structure layer into a lateral direction, a second structure layer formed on the dislocation propagation direction changing layer, and a buffer layer formed on the second structure layer for changing a propagation direction of a dislocation propagated in the second structure layer.
    Type: Application
    Filed: March 17, 2009
    Publication date: September 24, 2009
    Applicant: Hitachi Cable, Ltd.
    Inventors: Yoshihiko Moriya, Takeshi Tanaka, Yohei Otoki, Masae Sahara
  • Publication number: 20090224270
    Abstract: A group III nitride semiconductor thin film and a group III nitride semiconductor light emitting device using the same. The group III nitride semiconductor thin film includes a substrate with a concave and convex portions formed thereon; a buffer layer formed on the substrate and made of a group III nitride; and an epitaxial growth layer formed on the buffer layer and made of (11-20) plane gallium nitride. The group III nitride light emitting device includes the group III nitride semiconductor thin film. The present invention allows a high quality a-plane group III nitride semiconductor thin film and a group III nitride semiconductor light emitting device using the same.
    Type: Application
    Filed: April 14, 2009
    Publication date: September 10, 2009
    Applicants: SAMSUNG ELECTRO-MECHANICS CO., LTD., THE UNIVERSITY OF TOKUSHIMA
    Inventors: Rak Jun CHOI, Naoi YOSHIKI, Sakai SHIRO
  • Patent number: 7585706
    Abstract: The semiconductor device of this invention includes an active region formed from a group III nitride semiconductor grown on a substrate and an insulating oxide film formed in a peripheral portion of the active region by oxidizing the group III nitride semiconductor. On the active region, a gate electrode in Schottky contact with the active region extending onto the insulating oxide film and having an extended portion on the insulating oxide film is formed, and ohmic electrodes respectively serving as a source electrode and a drain electrode are formed with space from side edges along the gate length direction of the gate electrode.
    Type: Grant
    Filed: September 18, 2007
    Date of Patent: September 8, 2009
    Assignee: Panasonic Corporation
    Inventors: Katsunori Nishii, Kaoru Inoue, Toshinobu Matsuno, Yoshito Ikeda, Hiroyuki Masato
  • Publication number: 20090218578
    Abstract: A semiconductor device comprises an AlN layer, a GaN layer, and an AlGaN layer sequentially formed on a semiconductor substrate. A first opening extends through said GaN layer and said AlGaN layer and exposes part of an upper surface of the AlN layer. A second opening extends through the semiconductor substrate and exposes a part of a lower surface of the AlN layer, in a location facing the first opening. A upper electrode is exposed on an upper surface of the AlN layer in the first opening; and a lower electrode is disposed on a lower surface of the AlN layer in the second opening.
    Type: Application
    Filed: June 20, 2008
    Publication date: September 3, 2009
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Hideo Takeuchi, Yoshitsugu Yamamoto
  • Publication number: 20090218596
    Abstract: Various embodiments provide a buffer layer that is grown over a silicon substrate that provides desirable device isolation for devices formed relative to III-V material device layers, such as InSb-based devices, as well as bulk thin film grown on a silicon substrate. In addition, the buffer layer can mitigate parallel conduction issues between transistor devices and the silicon substrate. In addition, the buffer layer addresses and mitigates lattice mismatches between the film relative to which the transistor is formed and the silicon substrate.
    Type: Application
    Filed: February 13, 2009
    Publication date: September 3, 2009
    Inventors: Mantu K. Hudait, Mohamad A. Shaheen, Loren A. Chow, Peter G. Tolchinsky, Joel M. Fastenau, Dmitri Loubychev, Amy W. K. Liu
  • Publication number: 20090206324
    Abstract: Dislocation removal from a group III-V film grown on a semiconductor substrate is generally described. In one example, an apparatus includes a semiconductor substrate, a buffer film including a group III-V semiconductor material epitaxially coupled to the semiconductor substrate wherein the buffer film includes material melted by laser pulse irradiation and recrystallized to substantially remove dislocations or defects from the buffer film, and a first semiconductor film epitaxially grown on the buffer film wherein a lattice mismatch exists between the semiconductor substrate and the first semiconductor film.
    Type: Application
    Filed: February 15, 2008
    Publication date: August 20, 2009
    Inventors: Mantu K. Hudait, Peter G. Tolchinsky, Jack T. Kavalieros, Marko Radosavljevic
  • Publication number: 20090206371
    Abstract: A nitride semiconductor device includes a first, a second, and a third nitride semiconductor layers that are laminated on a foundation semiconductor layer in stated order, the third nitride semiconductor layer having a wider band gap as compared with the second nitride semiconductor layer, a recess area that is dug from an upper surface of the third nitride semiconductor layer down to a middle of the second nitride semiconductor layer, a first electrode and a second electrode respectively formed on one side and the other side of the recess area so as to be in contact with one of the third nitride semiconductor layer and the second nitride semiconductor layer, a dielectric film formed on the third nitride semiconductor layer and an inner surface of the recess area, and a control electrode formed on the dielectric film in the recess area.
    Type: Application
    Filed: February 18, 2009
    Publication date: August 20, 2009
    Inventor: Tohru OKA
  • Patent number: 7573059
    Abstract: A device grade III-V quantum well structure formed on a silicon substrate using a composite buffer architecture and the method of manufacture is described. Embodiments of the present invention enable III-V InSb quantum well device layers with defect densities below 1×108 cm?2 to be formed on silicon substrates. In an embodiment of the present invention, an InSb quantum well layer is sandwiched between two larger band gap barrier layers. In an embodiment of the present invention, InSb quantum well layer is strained. In a specific embodiment, the two larger band gap barrier layers are graded.
    Type: Grant
    Filed: August 2, 2006
    Date of Patent: August 11, 2009
    Assignee: Intel Corporation
    Inventors: Mantu K. Hudait, Mohamad A. Shaheen, Loren A. Chow, Peter G. Tolchinsky, Dmitri Loubychev, Joel M. Fastenau, Amy W. K. Liu
  • Publication number: 20090194791
    Abstract: A compound semiconductor device including an electron transport layer that is formed on a substrate and includes a III-V nitride compound semiconductor, a gate insulating film that is positioned above the compound semiconductor layer, and a gate electrode that is positioned on the gate insulating film. The gate insulating film includes a first insulating film that includes oxygen, at least a single metal element selected from a metal bonding with the oxygen and forming a metal oxide having a dielectric constant no less than 10, and at least a single metal element selected from Si and Al.
    Type: Application
    Filed: March 27, 2009
    Publication date: August 6, 2009
    Applicant: FUJITSU LIMITED
    Inventor: Masahito Kanamura