Forming Josephson Element Patents (Class 505/817)
  • Patent number: 8735326
    Abstract: Methods of forming superconducting devices are disclosed. In one embodiment, the method can comprise depositing a protective barrier layer over a superconducting material layer, curing the protective barrier layer, depositing a photoresist material layer over the protective barrier layer and irradiating and developing the photoresist material layer to form an opening pattern in the photoresist material layer. The method can further comprise etching the protective barrier layer to form openings in the protective barrier layer based on the opening pattern, etching the superconductor material layer based on the openings in the protective barrier layer to form openings in the superconductor material layer that define a first set of superconductor material raised portins and stripping the photoresist material layer and the protective barrier layer.
    Type: Grant
    Filed: May 19, 2010
    Date of Patent: May 27, 2014
    Assignee: Northrop Grumman Systems Corporation
    Inventors: Erica Folk, Patrick B. Shea, Andrew C. Loyd
  • Patent number: 8055318
    Abstract: A new family of superconducting materials with critical temperature up to 55 K have recently been discovered, comprising a crystal structure with atomic layers of iron and arsenic alternating with atomic layers of rare-earth oxide or alkaline earth. The present invention identifies structures for integrated circuit elements (including Josephson junctions) in these and related materials. These superconducting circuit elements will operate at a higher temperature than low-temperature superconductors such as niobium, and may be easier to manufacture than prior-art high-temperature superconductors based on copper-oxides.
    Type: Grant
    Filed: April 22, 2009
    Date of Patent: November 8, 2011
    Assignee: Hypres, Inc.
    Inventor: Alan M. Kadin
  • Patent number: 5710437
    Abstract: A radiation detecting device including a superconducting tunnel junction having a three-layer structure formed by depositing a lower electrode, a tunnel barrier layer, and an upper electrode in sequence. The upper electrode, the tunnel barrier layer and lower electrode have substantially aligned side walls around substantially their entire perimeters such that a cross-section of the three-layer structure along a path perpendicular to a direction of the deposition is substantially constant in shape and size along the direction of the deposition and such that no portion of the lower electrode or the upper electrode extends beyond the tunnel barrier layer. At least one of the upper electrode and the lower electrode is made of superconducting material.
    Type: Grant
    Filed: March 2, 1994
    Date of Patent: January 20, 1998
    Assignee: Nippon Steel Corporation
    Inventors: Masahiko Kurakado, Toru Takahashi, Atsuki Matsumura
  • Patent number: 5582877
    Abstract: A process for fabricating the Josephson junction includes the steps of preparing a substrate, forming a first superconducting layer, forming a second superconducting layer transversely on the first layer with an insulating layer interposed therebetween wherein the insulating layer is an oxide or nitride of the superconducting material, and injecting ion beams into the insulating layer so as to form low oxygen- or nitrogen-concentrated area linking the first and second layers.
    Type: Grant
    Filed: February 24, 1995
    Date of Patent: December 10, 1996
    Assignee: Shimadzu Corporation
    Inventors: Shinji Nagamachi, Masahiro Ueda, Kei Shinada, Mitsuyoshi Yoshii
  • Patent number: 5477061
    Abstract: A Josephson device comprises a first electrode layer of a superconducting material and containing Nb therein as a constituent element, an overlayer of a nitride of a refractory metal element provided on the first electrode layer, a barrier layer of an insulating compound that contains the metal element as a constituent element and acting as a barrier of a Josephson junction, the barrier layer being provided on the overlayer, and a second electrode layer of a superconducting material and containing Nb therein as a constituent element, the second electrode layer being provided on the barrier layer.
    Type: Grant
    Filed: September 20, 1991
    Date of Patent: December 19, 1995
    Assignee: Fujitsu Limited
    Inventor: Shinichi Morohashi
  • Patent number: 5401530
    Abstract: A process for producing a Josephson device is disclosed, wherein a Josephson junction is formed over a recess step by oblique deposition and a protective layer of conducting material or semiconducting material is formed on the Josephson junction. The actual thickness of the Josephson junction is controlled to be smaller due to the proximity effect.
    Type: Grant
    Filed: March 3, 1994
    Date of Patent: March 28, 1995
    Assignee: Osaka Gas Company, Ltd.
    Inventors: Itsuro Tamura, Satoshi Fujita, Masao Wada
  • Patent number: 5382566
    Abstract: A Josephson junction device comprising a single crystalline substrate including principal surface, a layer of the same material as the substrate formed on the principal surface of the substrate so as to form a step on the principal surface, and an oxide superconductor thin film formed on the principal surface of the substrate. The oxide superconductor thin film includes a first and a second superconducting portions respectively positioned above and below the step, which are constituted of single crystals of the oxide superconductor, a junction portion between the first and the second superconducting portions, which is constituted of a single crystal of the oxide superconductor of which crystal orientation is different from those of the first and second superconducting portions, and grain boundaries between the first superconducting portion and the junction portion and between the second superconducting portion and the junction portion, which constitute one weak link of the Josephson junction.
    Type: Grant
    Filed: June 1, 1993
    Date of Patent: January 17, 1995
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Saburo Tanaka, Takashi Matsuura, Hideo Itozaki
  • Patent number: 5321276
    Abstract: A superconducting tunnel junction radiation sensing device includes first and second superconductor electrodes and a tunnel barrier layer interposed therebetween. The tunnel barrier layer is made up of a thin-wall portion and a thick-wall portion each formed of a semiconductor or an insulator, and each having opposite surfaces respectively contacting the first and second superconductor electrodes, and each extending adjacent each other in a same horizontal plane between the first and second electrodes. The thick-wall portion has a vertical thickness which is at least twice that of the thin-wall portion. Furthermore, the thickness of the thin-wall portion is such that a tunnel effect is enabled therethrough form the first electrode to the second electrode, and the thickness of the thick-wall portion is such that a tunnel effect is substantially prohibited therethrough from the first electrode to the second electrode.
    Type: Grant
    Filed: October 1, 1991
    Date of Patent: June 14, 1994
    Assignee: Nippon Steel Corporation
    Inventors: Masahiko Kurakado, Atsuki Matsumura, Takeshi Kaminaga, Tooru Takahashi
  • Patent number: 5313074
    Abstract: In a Josephson device which can be employed as a sensor including superconductor for measuring an extremely weak magnetic field, a Josephson junction consisting of superconducting material is formed, and a covering layer consisting of ordinary conducting metal or semiconductor is formed on the Josephson junction. This enables the Josephson junction to be isolated from the oxidized atmosphere. Further, the covering layer is not to present any deterioration such as cracks even upon being subjected to a thermal hysteresis from very low temperature to ordinary temperature.
    Type: Grant
    Filed: November 27, 1991
    Date of Patent: May 17, 1994
    Assignee: Osaka Gas Company Limited
    Inventors: Itsuro Tamura, Satoshi Fujita, Masao Wada
  • Patent number: 5306705
    Abstract: A non-linear superconducting junction device comprising a layer of high transient temperature superconducting material which is superconducting at an operating temperature, a layer of metal in contact with the layer of high temperature superconducting material and which remains non-superconducting at the operating temperature, and a metal material which is superconducting at the operating temperature and which forms distributed Sharvin point contacts with the metal layer.
    Type: Grant
    Filed: May 6, 1993
    Date of Patent: April 26, 1994
    Assignee: Board of Trustees of the Leland Stanford Junior University
    Inventors: Matthew J. Holcomb, William A. Little
  • Patent number: 5306521
    Abstract: A method of manufacturing a DC superconducting quantum interference device comprises forming an insulating film over a portion of a resistance film. A lower electrode superconducting film is formed over the resistance film and the insulating film. A barrier layer is formed on a portion of the lower electrode superconducting film. An upper electrode is formed sandwiching the barrier layer between the lower electrode superconducting film and the upper electrode, so as to form a Josephson junction. To reduce the number of manufacturing steps, the lower electrode superconducting film is photolithographically patterned and/or etched to simultaneously form an input coil, a feedback coil and the Josephson junction. In another embodiment, after forming the upper electrode, an insulating film is formed over at least a portion of the lower electrode superconducting film. A superconducting film is formed over the insulating film in contact with the upper electrode.
    Type: Grant
    Filed: February 24, 1992
    Date of Patent: April 26, 1994
    Assignee: Seiko Instruments Inc.
    Inventors: Nobuhiro Shimizu, Kazuo Chinone, Norio Chiba
  • Patent number: 5306927
    Abstract: A high current amplifier, three terminal device, comprising a Josephson tunnel junction and a Schottky diode is configured so that the Josephson junction and Schottky diode share a common base electrode which is made very thin. Electrons which cross the Schottky barrier are supplied to the Josephson junction to obtain the amplified output current.
    Type: Grant
    Filed: August 15, 1991
    Date of Patent: April 26, 1994
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: Bruce J. Dalrymple, Arnold H. Silver, Randy W. Simon
  • Patent number: 5231295
    Abstract: A field-effect transistor comprises, on a substrate, a layer of semiconductor material incorporating natural or artificial inclusions of superconducting material. The source, drain and gate electrodes are made on this layer. Applications: field-effect transistors with low gate control voltage. FIG. 3.
    Type: Grant
    Filed: August 16, 1991
    Date of Patent: July 27, 1993
    Assignee: Thomson-CSF
    Inventors: Stephane Tyc, Alain Schuhl
  • Patent number: 5131976
    Abstract: A Josephson junction apparatus comprises a polymeric film having flexiblity, and a Josephson junction circuit formed on the polymeric film. The Josephson junction circuit includes a Josephson junction device and a wiring for connecting to the Josephson junction device. Namely, the Josephson junction apparatus has flexibility, and thus the Josephson junction apparatus can be placed not only on a flat surface but also it can be placed on a curved surface in practice. Furthermore, in the Josephson junction apparatus, when a functional polymeric film is used as a substrate of a Josephson junction of the Josephson junction device, a protective film is previously formed over the functional polymeric film, so that a wetting of the functional polymer film, which is caused by water or organic solvents being used used repeatedly during the manufacturing process, can be prevented and a dimensional stability of the film can be increased.
    Type: Grant
    Filed: November 13, 1990
    Date of Patent: July 21, 1992
    Assignee: Fujitsu Limited
    Inventor: Hiromasa Hoko
  • Patent number: 5057485
    Abstract: In a device wherein a region which includes a superconducting weak link or a Josephson junction is irradiated with light or an electromagnetic wave so as to detect the light or an electromagnetic wave on the basis of the change of a superconducting critical current or an output voltage; a light-sensitive superconducting device characterized in that the surface of a superconductor lies in contact with a photoconductive semiconductor in at least a part of the whole of the region which is irradiated with the light or the electromagnetic wave.
    Type: Grant
    Filed: May 11, 1988
    Date of Patent: October 15, 1991
    Assignee: Hitachi, Ltd.
    Inventors: Toshikazu Nishino, Ushio Kawabe, Mutsuko Hatano
  • Patent number: 4994434
    Abstract: A process is disclosed of producing on a crystalline silicon substrate a barrier layer triad capable of protecting a rare earth alkaline earth copper oxide conductive coating from direct interaction with the substrate. A silica layer of at least 2000 .ANG. in thickness is deposited on the silicon substrate, and followed by deposition on the silica layer of a Group 4 heavy metal to form a layer having a thickness in the range of from 1500 to 3000 .ANG.. Heating the layers in the absence of a reactive atmosphere to permit oxygen migration from the silica layer forms a barrier layer triad consisting of a silica first triad layer located adjacent the silicon substrate, a heavy Group 4 metal oxide third triad layer remote from the silicon substrate, and a Group 4 heavy metal silicide second triad layer interposed between the first and third triad layers.
    Type: Grant
    Filed: March 21, 1989
    Date of Patent: February 19, 1991
    Assignee: Eastman Kodak Company
    Inventors: Liang-Sun Hung, John A. Agostinelli
  • Patent number: 4985117
    Abstract: A method of manufacturing Josephson junctions includes steps of high Tc superconductor thin films on a substrates by chemical vapor deposition using raw materials, which includes at least yttrium, barium and copper, serving as vapor generating sources, and fabricating the high Tc superconductor thin films into micro-bridges to produce Josephson junctions.
    Type: Grant
    Filed: January 1, 1990
    Date of Patent: January 15, 1991
    Assignees: Kabushiki Kaisha Riken, Research Development Corporation of Japan
    Inventors: Hideyuki Kurosawa, Toshio Hirai, Hisanori Yamane, Tsutomu Yamashita
  • Patent number: 4891355
    Abstract: A method of producing a superconducting circuit by forming a film having a superconducting phase on a substrate and applying a laser beam to a part of the superconducting phase to cause transition of the part of the superconducting phase into a non-superconducting phase.
    Type: Grant
    Filed: August 22, 1988
    Date of Patent: January 2, 1990
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Noriki Hayashi, Satoshi Takano, Kenji Miyazaki, Noriyuki Yoshida
  • Patent number: 4878094
    Abstract: A self-powered electronic component, particularly, a Josephson junction, is formed of a layer of a superconductor epitaxially grown on a substrate formed of a single crystal of silicon. In accordance with one embodiment of the invention, the expitaxial superconductor layer is separated into two parts by a groove defined by a thin growth region, forming the Josephson junction. On the epitaxial layer at the first side of the junction is deposited a thin layer of an insertion material forming the positive pole of the Josephson junction as well as the cathode of a solid state power generator. On the epitaxial layer and over the thin layer of insertion material is deposited a separator, or fast ion conductor, which assumes the weak link of the Josephson junction as well as separates the ion source from the electronic exchanger and assumes the fast ion transport.
    Type: Grant
    Filed: March 30, 1988
    Date of Patent: October 31, 1989
    Inventor: Minko Balkanski
  • Patent number: H873
    Abstract: A method of making a Josephson Junction is disclosed which includes the steps of depositing a base electrode layer of a refractory superconducting material on a substrate, depositing a first passivation layer on the base electrode, depositing a barrier layer of refractory insulating semiconducting material on the passivation layer, depositing a second passivation layer on the barrier layer, and depositing a counter electrode on the second passivation layer. The layers are deposited at a substrate temperature of from about 50.degree. C. to about 700.degree. C. in an Ultra-High Vacuum sputtering system at a base pressure of less than or equal to 5.times.10.sup.-8 Torr. In the preferred embodiment a base electrode and counter electrode of NbN are separated by a barrier layer of hydrogenated silicon. When exposed to high post processing temperatures this structure maintains a chemically stable interface with the substrate.
    Type: Grant
    Filed: June 30, 1989
    Date of Patent: January 1, 1991
    Assignee: United States of America
    Inventors: Edward Cukauskas, William Carter