Sputter Coating Patents (Class 505/731)
  • Patent number: 8119571
    Abstract: Novel articles and methods to fabricate same with self-assembled nanodots and/or nanorods of a single or multicomponent material within another single or multicomponent material for use in electrical, electronic, magnetic, electromagnetic and electrooptical devices is disclosed. Self-assembled nanodots and/or nanorods are ordered arrays wherein ordering occurs due to strain minimization during growth of the materials. A simple method to accomplish this when depositing in-situ films is also disclosed. Device applications of resulting materials are in areas of superconductivity, photovoltaics, ferroelectrics, magnetoresistance, high density storage, solid state lighting, non-volatile memory, photoluminescence, thermoelectrics and in quantum dot lasers.
    Type: Grant
    Filed: August 3, 2006
    Date of Patent: February 21, 2012
    Inventors: Amit Goyal, Sukill Kang
  • Patent number: 7919435
    Abstract: The present invention relates to a method for producing a defect-containing superconducting film, the method comprising (a) depositing a phase-separable layer epitaxially onto a biaxially-textured substrate, wherein the phase-separable layer includes at least two phase-separable components; (b) achieving nanoscale phase separation of the phase-separable layer such that a phase-separated layer including at least two phase-separated components is produced; and (c) depositing a superconducting film epitaxially onto said phase-separated components of the phase-separated layer such that nanoscale features of the phase-separated layer are propagated into the superconducting film.
    Type: Grant
    Filed: September 30, 2008
    Date of Patent: April 5, 2011
    Assignee: UT-Battelle, LLC
    Inventor: Amit Goyal
  • Patent number: 6632539
    Abstract: The polycrystalline thin film is made of a composite oxide of a cubic crystal system which has a pyrochlore type crystalline structure of a composition represented as either AZrO or AHfO (A in the formula represents a rare earth element selected from among Y, Yb, Tm, Er, Ho, Dy, Eu, Gd, Sm, Nd, Pr, Ce and La) formed on the film forming surface of the polycrystalline substrate, wherein the grain boundary misalignment angle between the same crystal axes of different crystal grains in the polycrystalline thin film along a plane parallel to the film forming surface of the polycrystalline substrate are controlled within 30°.
    Type: Grant
    Filed: July 25, 2001
    Date of Patent: October 14, 2003
    Assignees: Fujikura Ltd., International Superconductivity Technology Center,
    Inventors: Yasuhiro Iijima, Mariko Kimura, Takashi Saitoh
  • Patent number: 6426320
    Abstract: A method for fabricating superconductor articles with an epitaxial layer is described. The method can be performed under conditions of relatively high pressure and low substrate surface temperature. The resulting epitaxial layers can demonstrate various advantageous features, including low pore density and/or inclusions with small average particle size diameter.
    Type: Grant
    Filed: December 29, 1999
    Date of Patent: July 30, 2002
    Assignee: American Superconductors Corporation
    Inventors: Leslie G. Fritzemeier, David M. Buczek
  • Patent number: 6218341
    Abstract: A process for preparing a superconductor which is a low anisotropy, high temperature superconductor, includes providing a target in molded form comprised of one of the superconductor or constituent elements of the superconductor, the superconductor having a layered crystal structure, having a superconducting transition temperature, Tc, of 110 K or more, and having a composition expressed by Cu1−zMzAe2Cax−1CuxOy where M is at least one member selected from the group consisting of (a) a trivalent ion of Tl, and (b) polyvalent ions of Mo, W, and Re, Ae is at least one of Ba and Sr, x ranges from 1 to 10, and y ranges from 2x+1 to 2x+4, and z ranges from 0<z≦0.5; and forming a film of the superconductor from the target on a substrate by one of sputtering or laser abrasion.
    Type: Grant
    Filed: June 4, 1999
    Date of Patent: April 17, 2001
    Assignee: Agency of Industrial Science and Technology
    Inventors: Hideo Ihara, Masayuki Hirabayashi, Akira Iyo
  • Patent number: 6214772
    Abstract: A method is presented for making a polycrystalline thin film (B) by depositing particles emitted from a target (36) on a substrate base (A) to form the film (B) constituted by the target material while concurrently irradiating the depositing particles with an ion beam generated by an ion source (39) at an angle of incidence, in a range of 50 to 60 degrees to a normal (H) to a film surface, and maintaining a film temperature at less than 300 degrees Celsius. This method is effective in producing an excellent alignment of crystal axes of the grains in the film when the film thickness exceeds 200 nm. The target material includes yttrium-stabilized zirconia but other material can also be used. A layer (C) of a superconducting substance formed on top of the polycrystalline thin film (B) produces a superconducting film (22) exhibiting excellent superconducting properties.
    Type: Grant
    Filed: June 18, 1998
    Date of Patent: April 10, 2001
    Assignee: Fujikura Ltd.
    Inventors: Yasuhiro Iijima, Mariko Hosaka, Nobuo Tanabe, Nobuyuki Sadakata, Takashi Saitoh
  • Patent number: 6172008
    Abstract: A process for preparing an oxide thin film which has a crystalline, clean and smooth surface on a substrate. The process is conducted by using an apparatus comprising a vacuum chamber in which an oxidizing gas of O2 including O3 can be supplied near the substrate so that pressure around the substrate can be increased while maintaining high vacuum near an evaporation source and Knudsen cell evaporation sources arranged in the vacuum chamber wherein the substrate is heated, molecular beam of constituent atoms of the oxide excluding oxygen are supplied from the K cell evaporation sources, an oxidizing gas is locally supplied to the vicinity of the substrate and a growing thin film is illuminated by ultraviolet.
    Type: Grant
    Filed: March 28, 1995
    Date of Patent: January 9, 2001
    Assignee: Sumitomo Electric Industries Ltd.
    Inventor: Takao Nakamura
  • Patent number: 6110392
    Abstract: The invention is a process for reducing roughness of a surface of a superconductor material (23) having an undesirable surface roughness (30 and 32) and a trilayer superconductor integrated circuit (100). The process for reducing roughness of a surface of superconductor material having an undesirable surface roughness includes coating the surface with an oxide layer (40) to fill the undesirable surface roughness and to produce an exposed oxide surface (42) with a roughness less than the surface roughness; and etching the exposed oxide surface to remove a thickness of the oxide layer followed by removing at least a portion of the oxide layer filling the undesirable surface roughness and a portion of the surface of the superconductor material to produce an exposed etched surface (44) comprised of at least the superconductor material which has a surface roughness less than the undesirable surface roughness.
    Type: Grant
    Filed: September 18, 1998
    Date of Patent: August 29, 2000
    Assignee: TRW Inc.
    Inventors: George L. Kerber, Michael Leung
  • Patent number: 6060433
    Abstract: The invention provides a structure comprising a high temperature superconducting layer deposited on a ceramic polycrystalline ferrite plate suitable for making commercial microwave devices. In one embodiment, the high temperature superconductor is yttrium barium copper oxide (YBCO), the ferrite is yttrium iron garnet (YIG), and the microwave device is a phase shifter. The method of making this embodiment comprises, polishing the YIG plate, depositing biaxially oriented yttria-stabilized zirconia (YSZ) to form a crystalline template using an ion-beam-assisted-deposition technique, depositing a CeO.sub.2 lattice matching buffer layer using pulsed laser deposition, depositing YBCO using pulsed laser deposition, and annealing the YBCO in oxygen. Etching the YBCO to form a meanderline patterned waveguide results in a high figure-of-merit microwave phase shifter when the device is cooled with liquid nitrogen and an external magnetic field is applied.
    Type: Grant
    Filed: January 26, 1999
    Date of Patent: May 9, 2000
    Assignee: NZ Applied Technologies Corporation
    Inventors: Yi-Qun Li, Hua Jiang
  • Patent number: 6037313
    Abstract: The method for forming superconducting films of complex oxide compounds in a process chamber according to the present invention includes the steps of:(a) placing a substrate near a target in a chamber so that the substrate is positioned to be generally perpendicular to a surface of the target, the target comprising a target material of complex oxide compounds; and(b) irradiating a laser beam to the surface of the target to vaporize or sublime the target material forming over the target a flame-shaped plume having on axis generally perpendicular to the surface of the target so that the target material is deposited onto a surface of the substrate, the surface of the substrate maintaining the position to be generally perpendicular to the surface of the target and being generally parallel to the axis of the plume, wherein the target rotates on an axis perpendicular to the surface of the target and the substrate rotates on an axis perpendicular to the surface of the substrate (off-axis geometry), and wherein the l
    Type: Grant
    Filed: September 12, 1995
    Date of Patent: March 14, 2000
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Tatsuoki Nagaishi, Hideo Itozaki
  • Patent number: 6027564
    Abstract: A method for fabricating composite articles with an epitaxial layer is described. The method can be performed under conditions of relatively high pressure and low substrate surface temperature. The resulting epitaxial layers can demonstrate various advantageous properties, such as low pore density and/or inclusions with small average particle size diameter.
    Type: Grant
    Filed: January 15, 1998
    Date of Patent: February 22, 2000
    Assignee: American Superconductor Corporation
    Inventors: Leslie G. Fritzemeier, David M. Buczek
  • Patent number: 6022832
    Abstract: A method for fabricating superconductor articles with an epitaxial layer is described. The method can be performed under conditions of relatively high pressure and low substrate surface temperature. The resulting epitaxial layers can demonstrate various advantageous features, including low pore density and/or inclusions with small average particle size diameter.
    Type: Grant
    Filed: January 15, 1998
    Date of Patent: February 8, 2000
    Assignee: American Superconductor Corporation
    Inventors: Leslie G. Fritzemeier, David M. Buczek
  • Patent number: 5939361
    Abstract: A substrate is set in a reaction chamber, to heat the substrate to a predetermined temperature. Tl, Ba, Ca, Cu and O are supplied to the substrate by a Tl evaporation source and a target, to cause a TlBaCaCuO film to grow on the substrate. The TlBaCaCuO film is crystallized for each formation of each of its blocks each having a layered structure. In an incomplete block which is being formed, the amount of evaporation of Tl by the heating is large, so that the amount of evaporation of Tl varies depending on the ratio of an uncrystallized region on its surface. In a complete block after the formation, the amount of evaporation of Tl by the heating is small, and is approximately constant. Film growth is stopped for a predetermined time period for each formation of the block, to control the amount of supply of Tl depending on the forming step of the block.
    Type: Grant
    Filed: March 17, 1998
    Date of Patent: August 17, 1999
    Assignee: Sanyo Electric Co., Ltd.
    Inventor: Masaaki Nemoto
  • Patent number: 5922651
    Abstract: Herein disclosed is a superconductive thin film formation method of forming a superconductive thin film having a high critical temperature and a low surface resistance. The method comprises a first step of depositing a superconductive thin film layer on a substrate under a first condition. The superconductive thin film layer has a thickness smaller than that of the superconductive thin film. The method further comprises a second step of introducing oxygen under a second condition. The method further comprises a third step of depositing a superconductive thin film layer on the previously deposited superconductive thin film layer under the first condition and fourth step of introducing oxygen under the second condition. The method further comprises a fifth step of repeating the third and fourth steps until the sum of the thicknesses of the superconductive thin film layers is substantially equal to the predetermined thickness of the superconductive thin film.
    Type: Grant
    Filed: November 25, 1997
    Date of Patent: July 13, 1999
    Assignee: Advanced Mobile Telecommunication Technology Inc.
    Inventors: Hiroki Hoshizaki, Masahiro Kawamura
  • Patent number: 5900391
    Abstract: Herein disclosed is a method for depositing a high Tc superconducting thin film. The superconducting thin film is deposited on one surface of a substrate. The substrate is exposed to an electromagnetic wave to heat the substrate during the process for depositing the superconducting thin film. Before the processes for depositing the superconducting thin film and exposing the substrate to the electromagnetic wave, a dummy film is formed on the other surface of the substrate. The dummy film has absorbency of the electromagnetic wave which is higher than that of the substrate. The dummy film together with the substrate is exposed to the electromagnetic wave while the superconducting thin film is deposited on the one surface of the substrate. The superconducting thin film thus deposited has superconductivity and high quality crystal structure.
    Type: Grant
    Filed: November 26, 1996
    Date of Patent: May 4, 1999
    Assignee: Advanced Mobile Telecommunication Technology Inc.
    Inventors: Nobuyoshi Sakakibara, Hiroki Hoshizaki, Yoshiki Ueno
  • Patent number: 5679625
    Abstract: A method of making a superconducting thin film of a Y--Ba--Cu--O series material by using a diode parallel plate type sputtering apparatus including a vacuum chamber, a substrate disposed within the vacuum chamber and having a substantially flat surface on which the superconducting thin film is to be formed, and a plate-shaped target functioning as a cathode and disposed within the vacuum chamber to parallelly face to the flat surface of the substrate, the target being made of the same material as the superconducting thin film, a plasma gas being introduced into the vacuum chamber, and a voltage being applied between the cathode and the substrate, wherein the method comprises the steps of applying a high frequency voltage having a frequency higher than 40 MHz between the cathode and the substrate to generate plasma of the introduced gas, superimposing a DC voltage (V) on the high frequency voltage in a polarity that the cathode becomes negative, and setting the DC voltage at a value where the DC voltage is su
    Type: Grant
    Filed: November 22, 1995
    Date of Patent: October 21, 1997
    Assignees: Nippon Steel Corporation, International Superconductivity Technology Center, Mitsubish Electric Corporation, Hokkaido Electric Power Co., Inc.
    Inventors: Wataru Ito, Tadataka Morishita, Norio Homma, Yukihisa Yoshida
  • Patent number: 5667650
    Abstract: An improved device for off-axis magnetron sputter deposition of inorganic oxide compounds having a sputter gun, target, substrate, gas flow means and enclosure chamber wherein the improvement comprises a hollow gas flow manifold positioned between the substrate and the target having at least one gas inlet and at least one outlet opening on the manifold, said outlet opening positioned to direct the gas flow away from the target and in the direction of the substrate, and a process for such deposition are disclosed.
    Type: Grant
    Filed: February 14, 1995
    Date of Patent: September 16, 1997
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Dean Willett Face, Kirsten Elizabeth Myers
  • Patent number: 5650378
    Abstract: The present invention relates to a polycrystalline thin film deposit acting as a substrate material composed of grains of a cubic structure in which the intergranular misorientation, defined as the orientation difference between the a-axes (or b-axes) of the neighboring grains, is less than 30 degrees. Such a substrate base is produced by depositing a target material on a base material by sputtering while irradiating the substrate base with ion beams at an oblique angle to the base. The preferred range of the oblique angle is between 40 to 60 degrees. Examples are presented of application of such textured polycrystalline substrate base for the production of superconducting oxide thin layer of outstanding superconducting properties.
    Type: Grant
    Filed: August 3, 1995
    Date of Patent: July 22, 1997
    Assignee: Fujikura Ltd.
    Inventors: Yasuhiro Iijima, Nobuo Tanabe
  • Patent number: 5648321
    Abstract: Described is a process for manufacturing thin films by periodically depositing (DEP) a number of block layers consisting of different base materials on a substrate (multilayer deposition), wherein the thickness of the layers (LT) is restricted to one to 20 monolayers and deposition as well as crystallization of the thin film is completed at approximately constant temperature without performing a separate annealing step. The method can be used to produce thin films of high-T.sub.c -superconductors. It allows a better control of the crystal growth of ternary or higher compounds with comparatively large unit cells.
    Type: Grant
    Filed: September 13, 1993
    Date of Patent: July 15, 1997
    Assignee: International Business Machines Corporation
    Inventors: Johannes Georg Bednorz, Andrei Catana, Jean Pierre Locquet, Erich Maechler, Carl Alexander Mueller
  • Patent number: 5629268
    Abstract: A process for depositing successively a plurality of thin films on a bottom superconductor layer made of oxide superconductor deposited on a substrate in a single chamber under a condition, the bottom superconductor layer is heated in ultra-high vacuum at a temperature which is lower than the oxygen-trap temperature (T.sub.trap) at which oxygen enter into the oxide superconductor but higher than a temperature which is lower by 100.degree. C. than the oxygen-trap temperature (T.sub.trap -100.degree. C.) and then the first thin film is deposited thereon.
    Type: Grant
    Filed: June 1, 1995
    Date of Patent: May 13, 1997
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: So Tanaka, Takao Nakamura, Michitomo Iiyama
  • Patent number: 5595959
    Abstract: A method of forming a high-Tc microbridge superconductor device is disclosed, which comprises the steps of forming an inclined step on the surface of a substrate, the inclined step having an angle of inclination of from about 20 to about 80 degrees; depositing a layer of c-axis oriented superconductor material overlying the substrate such that there is a break in the layer of superconductor material at the inclined step; and depositing a layer of normal material overlying the layer of c-axis oriented superconductor material.
    Type: Grant
    Filed: November 22, 1994
    Date of Patent: January 21, 1997
    Assignee: Biomagnetic Technologies, Inc.
    Inventors: Mark S. DiIorio, Shozo Yoshizumi, Kai-Yuen Yang
  • Patent number: 5585332
    Abstract: A perovskite type superconductor film having a high content, almost a single phase, of the high Tc phase is formed by the steps of: depositing at least one first film of a first material (e.g., a composite oxide of Bi-Sr-Ca-Cu-O system or Tl-Ba-Ca-Cu-O system) constituting a perovskite type superconductor over a substrate; depositing at least one second film of a second material containing an oxide or element (Bi.sub.2 O.sub.3, Tl.sub.2 O.sub.3, PbO.sub.x, etc., particularly PbO.sub.x) having a vapor pressure of more than 10.sup.-4 Pa at 800.degree. C. at least as a main component over the substrate; to thereby form a stack of the first and second films; and heat treating the stack of the first and second films to form the perovskite type superconductor film on the substrate. Further, preferred compositions of the as-deposited films or stack are determined.
    Type: Grant
    Filed: January 25, 1995
    Date of Patent: December 17, 1996
    Assignee: Fujitsu Limited
    Inventors: Atsushi Tanaka, Nobuo Kamehara, Koichi Niwa
  • Patent number: 5567674
    Abstract: A thin film of oxide superconductor consisting of more than two portions (1, 11, 12) each possessing a predetermined crystal orientation and deposited on a common surface of a substrate (2). At least one selected portion (10) of thin film of oxide superconductor is deposited on a thin under-layer (4, 100) which facilitates crystal growth of selected portions and which is deposited previously on the substrate. The selected portions (10) may consist of a-axis oriented thin film portions while non-selected portions (11, 12) may consists of c-axis oriented thin film portions. The thin under-layer can be a buffer layer (4) or a very thin film (100) of oxide superconductor.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: October 22, 1996
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Hiroshi Inada, Michitomo Iiyama
  • Patent number: 5488031
    Abstract: A process for making high temperature superconducting oxide films comprising using a sintered body of Y-Ba-Cu-O or Bi-Sr-Ca-Cu-O oxide as a sputtering target and using a mixture of argon and oxygen as a sputtering gas, forming glow discharge between the substrate and the target under a pressure of 0.5-2.5 torr and at a sputtering current density of 5-35 mA/cm.sup.2, and then cooling the substrate after the oxide film has been grown to a desired thickness. The critical temperature of the in-situ produced superconducting oxide film of Y-Ba-Cu-O is 90 K and that of Ba-Sr-Ca-Cu-O is 80 K.An apparatus for the preparation of high temperature superconducting oxide films is also provided. The apparatus for in-situ making such high temperature superconducting oxide film is easy to heat the substrate and control its temperature without problems of conventional deposition methods.
    Type: Grant
    Filed: April 5, 1995
    Date of Patent: January 30, 1996
    Assignee: Industrial Technology Research Institute
    Inventor: Ran-Jin Lin
  • Patent number: 5478800
    Abstract: A process for preparing a superconducting thin film of K.sub.2 NiF.sub.4 -type oxides such as [La, Ba ].sub.2 CuO.sub.4, or [La, Sr ].sub.2 CuO having higher transition temperature of superconductivity which can be used for Josephson Junctions devices or the like by sputtering technique.The process of the present invention is characterized in that the target used in the sputtering technique is composed of a mixture of compounds which .contain at least La, one element M selected from a group of Ia, IIa and IIIa elements of the Periodic Table, and Cu. The compounds may be oxides, carbonates, nitrate or sulfates of La, said element M, and Cu. Said mixture which is used as the target is preferably sintered into a form of a sintered body. The substrate on which the thin film is deposited is preferably heated at a temperature between 100 and 1,200.degree. C. during sputtering and the deposited thin film is preferably heat-treated at a temperature between 600.degree. and 1,200.degree. C.
    Type: Grant
    Filed: November 28, 1994
    Date of Patent: December 26, 1995
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Hideo Itozaki, Nobuhiko Fujita, Kengo Okura
  • Patent number: 5476838
    Abstract: The invention relates to a process for producing thin films in which the pressure of the process gas is kept constant in a process chamber with a gas inlet and outlet, a target and a substrate, while material is sputtered from the target and deposited on the substrate. The invention also relates to a process for producing thin films. It is the purpose of the invention to create a process providing a more homogenous film. According to the invention, to this end the process gas is caused to reach the plasma. Alternatively, either one or several emission lines may be spectroscopically detected in a spatial region and, after a desired cross sectional shape has been set, it is kept constant in time by subsequently regulating the process gas mixing ratio.
    Type: Grant
    Filed: October 14, 1993
    Date of Patent: December 19, 1995
    Assignee: Forschungszentrum Julich
    Inventors: Roger Wordenweber, Ursus Kruger, Rolf Kutzner
  • Patent number: 5439877
    Abstract: In-situ process are provided for 1) depositing on a substrate a crystalline thin film of a high temperature superconducting oxide by exposing the back surface of the substrate, i.e., the surface of the substrate opposite the surface on which the thin film is deposited, to radiation from a direct radiant heat source, thereby heating the substrate to the desired growth temperature, and maintaining the radiation and thereby the desired growth temperature during the deposition of the thin film, and 2) depositing a crystalline thin film of high temperature superconducting oxides onto both the front and back surfaces of a substrate.
    Type: Grant
    Filed: March 24, 1994
    Date of Patent: August 8, 1995
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Dean W. Face
  • Patent number: 5430014
    Abstract: c-axis oriented YBa.sub.2 Cu.sub.3 O.sub.7 layers are grown with intervening SrTiO.sub.3 layers bridged over steps at which there is a transformation to a-axis crystal-oriented growth. The multilayer superconductor has YBa.sub.2 Cu.sub.3 O.sub.7 layers which are not thicker than 500 nm while the intervening layers of SrTiO.sub.3 have thicknesses of 20 to 30 nm.
    Type: Grant
    Filed: October 30, 1992
    Date of Patent: July 4, 1995
    Assignee: Forschungszentrum Julich GmbH
    Inventors: Helmut Soltner, Ulrich Poppe, Knut Urban
  • Patent number: 5426092
    Abstract: A thin film, high T.sub.c fluorinated, superconducting having a lattice structure differing from the lattice structure of the material substrate, such as sapphire or stainless steel, upon which it is grown. The superconducting material is characterized by basal plane alignment of the unit cells thereof even though the substrate does not possess a perovskite lattice structure. A laser ablation technique is used to evaporate material from a fluorinated pellet of target material to deposit the fluorinated superconducting material on the substrate. The instant invention provides for a low pressure and relatively low temperature method of depositing a superconducting film which is characterized by (1) a minimal number of high angle grain boundaries typically associated with polycrystalline films, and (2) aligned a, b, and c axes of the unit cells thereof so as to provide for enhanced current carrying capacities.
    Type: Grant
    Filed: June 25, 1992
    Date of Patent: June 20, 1995
    Assignee: Energy Conversion Devices, Inc.
    Inventors: Stanford R. Ovshinsky, Rosa Young
  • Patent number: 5389606
    Abstract: An in-situ process for preparing thin films which contain relatively volatile and involatile oxides is disclosed, in particular, crystalline thin films of oxides of conductors, superconductors or ferroelectric materials, wherein separate sources of the relatively volatile and involatile oxides during depositon of the thin film are employed.
    Type: Grant
    Filed: November 12, 1993
    Date of Patent: February 14, 1995
    Assignee: E. I. du Pont de Nemours and Company
    Inventor: Dean W. Face
  • Patent number: 5376627
    Abstract: Provided herein is a method of efficiently preparing a thin film having a higher critical temperature as to an oxide superconducting material containing Tl. A thin film of an oxide containing Tl is formed and then heat treated at a temperature of about 850.degree. to 950.degree. C. for a short time, and thereafter further heat treated at a temperature, which is lower than the preceding heat treatment temperature, of at least about 750.degree. C. for a long time. The thin film is heat treated in an atmosphere having an oxygen partial pressure of not more than about 0.1 atm. In formation of a Tl superconducting thin film, on the other hand, a 1212 phase layer is reacted with an amorphous Ca--Cu--O layer to form a 1223 phase layer, or a layer containing volatile metal elements (Tl, Bi and Pb, for example) and oxygen is reacted with another layer containing other elements than the volatile metal elements to form a superconducting film having a high critical temperature.
    Type: Grant
    Filed: March 5, 1993
    Date of Patent: December 27, 1994
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Yasuko Torii, Katsuya Hasegawa, Hiromi Takei
  • Patent number: 5364835
    Abstract: A method of producing an oxide superconducting material comprises the steps of adding a halogen element to an oxide superconducting material by ion injection and thermal diffusion, forming a film either on the oxide material before or after the adding step, and applying heat treatment after the forming step to improve the electric property in the near-surface portion.
    Type: Grant
    Filed: February 16, 1993
    Date of Patent: November 15, 1994
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventor: Shunpei Yamazaki
  • Patent number: 5362710
    Abstract: A process for preparing a thin film of superconducting material is disclosed in which films are deposited from a defined target. The thin films prepared by the process are characterized by high critical temperature of superconductivity and a smaller discrepancy between the critical temperature and the onset temperature at which superconductivity is observed.
    Type: Grant
    Filed: December 28, 1992
    Date of Patent: November 8, 1994
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Nobuhiko Fujita, Tadakazu Kobayashi, Hideo Itozaki, Saburo Tanaka, Shuji Yazu, Tetsuji Jodai
  • Patent number: 5342828
    Abstract: A superconducting Tl--Pb--Sr--Ca--Cu--O thin film comprised of at least one phase of the formula Tl.sub.0.5 Pb.sub.0.5 Sr.sub.2 Ca.sub.1+n Cu.sub.2+n O.sub.7+2n where n=0, 1 or 2 is disclosed, which is prepared by a process comprising sputtering an oxide film onto a dielectric substrate from an oxide target containing preselected amounts of Tl, Pb, Sr, Ca and Cu, and heating an oxygen-containing atmosphere in the deposited film in the presence of a source of thallium oxide and lead oxide and cooling the film.
    Type: Grant
    Filed: January 29, 1993
    Date of Patent: August 30, 1994
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Dennis J. Kountz, Frank M. Pellicone
  • Patent number: 5330966
    Abstract: An oxide superconducting layer is formed on a base material of silver, whose single side is coated with MgO, or single-crystalline MgO for depositing a Bi.sub.2 Sr.sub.2 Ca.sub.2 Cu.sub.3 phase in a crystallographically oriented state by sputtering, CVD or laser ablation. Metal lead or lead oxide is then laid thereon by sputtering to obtain a two-layer structure, and the two-layer structure is heat treated in the atmospheric air. Thus, a bismuth oxide superconducting film, which is excellent in crystal orientation as well as denseness and thereby having high critical current density, is formed on the base material.
    Type: Grant
    Filed: June 26, 1992
    Date of Patent: July 19, 1994
    Assignees: Sumitomo Electric Industries, Inc., The Kansai Electric Power Co., Inc.
    Inventors: Noriki Hayashi, Satoshi Takano
  • Patent number: 5317006
    Abstract: An improved cathode for a sputtering system includes a metal cylinder and strips of material bonded to the inside of the metal cylinder and/or material sprayed onto the inside of the metal cylinder. The strips may have various specified compositions and/or configurations and/or other characteristics which enhance the ability of the sputtering system to deposit films of high temperature superconductor material on substrates.
    Type: Grant
    Filed: October 4, 1991
    Date of Patent: May 31, 1994
    Assignee: Microelectronics and Computer Technology Corporation
    Inventor: Nalin Kumar
  • Patent number: 5314870
    Abstract: A process for preparing a thin film of oxide superconductor on a single crystal substrate of semiconductor by RF sputtering. At first, an under-layer of an oxide having a thickness of 50 to 200 .ANG. is deposited on the single crystal substrate of semiconductor at a substrate temperature of lower than 500.degree. C., and secondly an upper-layer of superconducting oxide material is deposited on said under-layer at a substrate temperature of higher than 600.degree. C.
    Type: Grant
    Filed: October 19, 1992
    Date of Patent: May 24, 1994
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Takashi Matsuura, Kenjiro Higaki, Hideo Itozaki
  • Patent number: 5312803
    Abstract: In an oxide superconducting film wiring, when the line width is reduced, the evaporation of a component during firing becomes so vigorous that it becomes impossible to form a desired single crystal phase, which causes a significant lowering in the properties of the oxide superconducting wiring. This problem can be solved by preventing the evaporation of the evaporable component during the firing. Examples of this include a process wherein plate is placed above the superconductor forming material film wiring pattern on the substrate so as to face each other, the plate comprising a material having no chemical influence on the superconducting wiring, and a pattern of a material containing an evaporable component is arbitrarily formed, a process wherein a pattern having a smaller line width is sandwiched between patterns having a larger line width, and a process wherein the firing atmosphere or the concentration of the evaporable component in the pattern is varied depending upon the line width.
    Type: Grant
    Filed: June 16, 1992
    Date of Patent: May 17, 1994
    Assignee: Fujitsu Limited
    Inventors: Atsushi Tanaka, Kazunori Yamanaka, Nobuo Kamehara, Koichi Niwa
  • Patent number: 5308801
    Abstract: A method is disclosed to increase the critical transition temperature of superconducting materials by the selective application of stress to specific crystal directions. It has been found that by applying tensile stresses in certain directions and compressive stresses in other directions that the critical temperature of superconducting materials can be substantially increased.
    Type: Grant
    Filed: July 22, 1992
    Date of Patent: May 3, 1994
    Assignees: Duke University, IBM Corporation
    Inventors: F. Hadley Cocks, Nancy J. Bolinger, Holly M. Hammarstrom
  • Patent number: 5306405
    Abstract: A method for preparing a slurry target for use in a sputtering apparatus. The target material is ground into a powder form, and mixed with a solvent to form a slurry. The slurry is poured into a target mold and allowed to slow dry by evaporation at or near room temperature. The target is mechanically stable, can be positioned in any orientation without falling out of the mold, and resists failure from thermal stresses during sputtering.
    Type: Grant
    Filed: June 26, 1992
    Date of Patent: April 26, 1994
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Robert D. Lorentz, Joseph H. Sexton
  • Patent number: 5306698
    Abstract: Improved processes for making thin film and bulk thallium superconductors are described, as well as Tl superconductors having high critical current densities and low surface impedance. An annealing step in a reduced oxygen atmosphere is used to convert compounds containing thallium, calcium, barium and copper to a Tl-2223 superconducting phase or to convert an oxide having the nominal composition Tl.sub.2 Ca.sub.2 Ba.sub.2 Cu.sub.3 O.sub.x to a crystalline Tl-2223 phase. The oxygen pressure during annealing is controlled to be below the thermodynamic stability limit for conversion of Tl-2223 to Tl-2122 and secondary phases. Temperatures less than 880.degree. C. are used, the oxygen pressure being sufficient to prevent excess thallium loss so that the Tl content in the final Tl-2223 phase is Tl.sub.1.6-2.0. Electrical devices including SQUIDs can be made with these improved superconductors.
    Type: Grant
    Filed: October 10, 1991
    Date of Patent: April 26, 1994
    Assignee: International Business Machines Corporation
    Inventors: Byung T. Ahn, Robert B. Beyers, Wen Y. Lee
  • Patent number: 5306702
    Abstract: A process for producing a Bi-based perovskite superconducting film, comprising the steps of forming on a substrate a Pb-film, containing Bi-base material film comprising Bi, Pb, Sr, Ca and Cu in a Bi:Pb:Sr:Ca:Cu molar ratio of (1.9 to 2.1):(1.2 to 2.2, preferably 1.5 to 1.8):2:(1.9 to 2.2):(3 to 3.5) and sintering the Pb-containing Bi-base material film in an oxygen-containing atmosphere. The sintering step includes a main sintering period of 20 to 120 minutes, in which the temperature is raised from a first temperature to a second temperature, with the second temperature being in a range of 850.degree. to 860.degree. C., and the temperature rise in the main sintering period of 20 to 120 minutes being from 3.degree. to 10.degree. C.
    Type: Grant
    Filed: June 17, 1992
    Date of Patent: April 26, 1994
    Assignee: Fujitsu Limited
    Inventors: Atsushi Tanaka, Nobuo Kamehara, Koichi Niwa
  • Patent number: 5296455
    Abstract: A compound oxide superconductor represented by the general formula:Bi.sub.4+d (Sr.sub.1-x, Ca.sub.x).sub.m Cu.sub.n O.sub.p+yin which,"d" is an amount of excess bismuth and satisfies a range of 0<d.ltoreq.1.2,"m" is a number which satisfies a range of 6.ltoreq.m.ltoreq.10,"n" is a number which satisfies a range of 4.ltoreq.n.ltoreq.8,"p"=6+m+n,"x" is a number which satisfies a range of 0<x<1, and"y" is a number which satisfies a range of -2.ltoreq.<y.ltoreq.+2.A preferred example is a compound oxide system having the following general formula:Bi.sub.4+d Sr.sub.4 Ca.sub.4 Cu.sub.6 O.sub.20+yin which "d" is a number which satisfies the range 0.4.ltoreq.d.ltoreq.1.2 and "y" is a number which satisfies a range of -2.ltoreq.y.ltoreq.+2. The critical current density (J.sub.c) is improved by increasing the amount of bismuth with respect to the stoichiometric amount. A superconducting thin film is deposited on a substrate by physical vapor deposition such as sputtering.
    Type: Grant
    Filed: May 7, 1992
    Date of Patent: March 22, 1994
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Keizo Harada, Hideo Itozaki, Kenjiro Higaki, Shuji Yazu
  • Patent number: 5296458
    Abstract: An epitaxial structure comprising a silicon containing substrate and a high T.sub.c copper-oxide-based superconducting layer, which may include an intermediate layer between the silicon substrate and the superconductor layer. Epitaxial deposition is accomplished by depositing a superconductor on a (001) surface of silicon in a manner in which the unit cell of the superconductor layer has two out of three of its crystallographic axes rotated 45 degrees with respect to the corresponding axes of the silicon unit cell, the remaining axis of the superconductor unit cell being normal to the Si (001) surface.
    Type: Grant
    Filed: June 4, 1992
    Date of Patent: March 22, 1994
    Assignee: International Business Machines Corporation
    Inventor: Franz J. Himpsel
  • Patent number: 5292718
    Abstract: Improvement in a process for fabricating a superconducting junction by depositing successively a first oxide superconductor thin layer, a non-superconducting intermediate thin film layer and a second oxide superconductor thin film layer on a substrate in this order.In the invention, the non-superconducting intermediate thin film layer is composed of MgO and the substrate is preheated at 600.degree.-650.degree. C. for at least 5 minutes in the presence of O.sub.2, and is heated at a temperature between 200.degree. and 400.degree. C. during the non-superconducting intermediate thin film layer is deposited.
    Type: Grant
    Filed: October 6, 1992
    Date of Patent: March 8, 1994
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Saburo Tanaka, Hidenori Nakanishi, Hideo Itozaki, Takashi Matsuura
  • Patent number: 5290758
    Abstract: Coatings such as high Tc superconductor material on substrates which incorporate reactive gases like oxygen and nitrogen are formed by providing the substrate so that it is spaced from the target region in a coating chamber, forming particles of the coating material by plasma from a cathodic target and entraining the particles to the substrate spaced from the plasma in a gas stream including the reactive gas and at a pressure of 0.1 to 20 mbar.
    Type: Grant
    Filed: March 10, 1992
    Date of Patent: March 1, 1994
    Assignee: Forschungszentrum Julich GmbH
    Inventor: Roger Wordenweber
  • Patent number: 5286712
    Abstract: This invention relates to new superconducting material having a composition represented by the general formula:A.sub.u B.sub.v C.sub.w D.sub.x E.sub.
    Type: Grant
    Filed: September 30, 1992
    Date of Patent: February 15, 1994
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Nobuhiko Fujita, Tadakazu Kobayashi, Hideo Itozaki, Saburo Tanaka, Shuji Yazu, Tetsuji Jodai
  • Patent number: 5283233
    Abstract: A method for producing a superconducting layer of YBa.sub.2 CU.sub.3 O.sub.7 on a sapphire substrate utilizes the steps of epitaxially growing an intermediate layer that at least contains a yttrium-stabilized zirconium oxide layer directly on the substrate, and then epitaxially growing a superconducting layer on the intermediate layer. In one embodiment, the step of growing the intermediate layer grows two sub-layers, with the first sub-layer being a yttrium-stabilized zirconium oxide layer and a second sub-layer being a yttrium oxide layer applied onto the first sub-layer.
    Type: Grant
    Filed: October 3, 1991
    Date of Patent: February 1, 1994
    Assignee: Siemens Aktiengesellschaft
    Inventors: Harald Schmidt, Klaudia Hradil, Wolfram Wersing
  • Patent number: 5280013
    Abstract: A superconducting electronic circuit device, useful when impedance matching is desired, especially suited to microwave frequencies, consisting of a thin dielectric layer with superconducting layers on both sides. A superconductor such as Yttrium Barium Copper Oxide (YBCO) is formed on a first substrate such as lanthanum aluminate. A protective layer like gold is deposited on the YBCO and a second carrier substrate is bonded to the protected YBCO. The first substrate is then thinned into a thin dielectric film and a second layer of superconductor is epitaxially grown thereon to create the desired circuits.
    Type: Grant
    Filed: October 29, 1992
    Date of Patent: January 18, 1994
    Assignee: Conductus, Inc.
    Inventors: Nathan Newman, Aharon Kapitulnik, Brady F. Cole, Randy W. Simon
  • Patent number: 5276010
    Abstract: A process for producing an oxide crystalline thin film having a structure in which atomic layers having different chemical compositions are laminated along the film thickness direction, the process including the steps of depositing amorphous atomic layers on a substrate, layer by layer and heating the amorphous deposit to crystallize the deposit, the respective amorphous atomic layers having the same chemical compositions as those of the corresponding atomic layers of the oxide crystal structure and being stacked in an order corresponding to the atomic lamination of the crystal structure.
    Type: Grant
    Filed: February 15, 1991
    Date of Patent: January 4, 1994
    Assignee: Fujitsu Limited
    Inventor: Nobuo Sasaki