Patents by Inventor Carlos A. Paz de Araujo

Carlos A. Paz de Araujo has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6133050
    Abstract: A precursor solution formed of a liquid polyoxyalkylated metal complex in as solvent is applied to a substrate in the formation of a metal oxide thin film. The liquid thin film is baked in air to a temperature up to 500.degree. C. while UV radiation having a wavelength ranging from 180 nm to 300 nm is applied. The thin film can be twice-baked at increasing temperatures while UV radiation is applied at one or both bakings. The film is then annealed at temperature ranging from about 700.degree. C. to 850.degree. C. to produce a thin-film solid metal oxide product. Alternatively, the UV radiation may be applied to the liquid precursor, the thin film may be annealed with UV radiation, or combinations of such applications of UV radiation to the precursor, to the thin film before or after baking, and/or UV annealing may be used. The use of UV radiation significantly reduces the leakage current and carbon impurity content of the final metal oxide.
    Type: Grant
    Filed: March 17, 1995
    Date of Patent: October 17, 2000
    Assignees: Symetrix Corporation, Matsushita Electronics Corporation
    Inventors: Masamichi Azuma, Larry D. McMillan, Carlos A. Paz de Araujo, Michael C. Scott
  • Patent number: 6130103
    Abstract: An integrated circuit is formed that contains a ferroelectric element comprising metal oxide material containing at least two metals. Various methods and structures are applied to minimize the degradation of ferroelectric properties caused by hydrogen during fabrication of the circuit. Oxygen is added to the some elements of the integrated circuit to serve as a getter of hydrogen during fabrication steps. To minimize hydrogen degradation, the ferroelectric compound can be fabricated from a liquid precursor containing one or more of the constituent metals in excess of the amount corresponding to a stoichiometrically balanced concentration. A hydrogen barrier layer, preferably comprising titanium nitride, is formed to cover the top of the ferroelectric element. A hydrogen heat treatment in hydrogen gas is performed on the integrated circuit at a temperature from 200.degree. to 350.degree. C.
    Type: Grant
    Filed: April 17, 1998
    Date of Patent: October 10, 2000
    Assignees: Symetrix Corporation, NEC Corporation
    Inventors: Joseph D. Cuchiaro, Akira Furuya, Carlos A. Paz de Araujo, Yoichi Miyasaka
  • Patent number: 6116184
    Abstract: A mass flow controller controls the delivery of a precursor to a mist generator. The precursor is misted utilizing a venturi in which a combination of oxygen and nitrogen gas is charged by a corona wire and passes over a precursor-filled throat. The mist is refined using a particle inertial separator, electrically filtered so that it comprises predominately negative ions, passes into a velocity reduction chamber, and then flows into a deposition chamber through inlet ports in an inlet plate that is both a partition between the chambers and a grounded electrode. The inlet plate is located above and substantially parallel to the plane of the substrate on which the mist is to be deposited. The substrate is positively charged to a voltage of about 5000 volts. There are 440 inlet ports per square inch in an 39 square inch inlet port area of the inlet plate directly above the substrate. The inlet port area is approximately equal to the substrate area.
    Type: Grant
    Filed: November 17, 1997
    Date of Patent: September 12, 2000
    Assignees: Symetrix Corporation, Primaxx, Inc.
    Inventors: Narayan Solayappan, Robert W. Grant, Larry D. McMillan, Carlos A. Paz de Araujo
  • Patent number: 6110531
    Abstract: A mist is generated by a venturi from liquid precursors containing compounds used in chemical vapor deposition, transported in carrier gas through tubing at ambient temperature, passed into a heated zone where the mist droplets are gasified at a temperature of between 100.degree. C. and 200.degree. C., which is lower than the decomposition temperature of the precursor compounds. The gasified liquid is injected through an inlet assembly into a deposition reactor in which there is a substrate heated to from 400.degree. C. to 600.degree. C., on which the gasified compounds decompose and form a thin film of layered superlattice compound.
    Type: Grant
    Filed: July 14, 1997
    Date of Patent: August 29, 2000
    Assignee: Symetrix Corporation
    Inventors: Carlos A. Paz de Araujo, Larry D. McMillan, Narayan Solayappan, Jeffrey W. Bacon
  • Patent number: 6104049
    Abstract: A coating of liquid precursor containing a metal is applied to a first electrode, baked on a hot plate in oxygen ambient at a temperature not exceeding 300.degree. C. for five minutes, then RTP annealed at 675.degree. C. for 30 seconds. The coating is then annealed in oxygen or nitrogen ambient at 700.degree. C. for one hour to form a thin film of layered superlattice material with a thickness not exceeding 90 nm. A second electrode is applied to form a capacitor, and a post-anneal is performed in oxygen or nitrogen ambient at a temperature not exceeding 700.degree. C. If the material is strontium bismuth tantalate, the precursor contains u mole-equivalents of strontium, v mole-equivalents of bismuth, and w mole-equivalents of tantalum, where 0.8.ltoreq.u.ltoreq.1.0, 2.0.ltoreq.v.ltoreq.2.3, and 1.9.ltoreq.w.ltoreq.2.1.
    Type: Grant
    Filed: January 11, 1999
    Date of Patent: August 15, 2000
    Assignee: Symetrix Corporation
    Inventors: Narayan Solayappan, Vikram Joshi, Carlos A. Paz de Araujo, Larry D. McMillan, Shinichiro Hayashi, Tatsuo Otsuki
  • Patent number: 6080592
    Abstract: An integrated curcuit includes a layered superlattice material having the .sub.formula A1w1.sup.+a1 A2.sub.w2.sup.+a2 . . . Aj.sub.wj.sup.+aj S1.sub.x1.sup.+s1 S2.sub.x2.sup.+s2 . . . Sk.sub.xk.sup.+sk B1.sub.y1.sup.+b1 B2.sub.y2.sup.+b2 . . . Bl.sub.yl.sup.+bl Q.sub.z.sup.-2, where A1, A2 . . . Aj represent A-site elements in a perovskite-like structure, S1, S2 . . . Sk represent superlattice generator elements, B1, B2 . . . Bl represent B-site elements in a perovskite-like structure, Q represents an anion, the superscripts indicate the valences of the respective elements, the subscripts indicate the number of atoms of the element in the unit cell, and at least w1 and y1 are non-zero. Some of these materials are extremely low fatigue ferroelectrics and are applied in non-volatile memories. Others are high dielectric constant materials that do not degrade or breakdown over long periods of use and are applied in volatile memories.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: June 27, 2000
    Assignee: Symetrix Corporation
    Inventors: Carlos A. Paz de Araujo, Joseph D. Cuchiaro, Michael C. Scott, Larry D. McMillan
  • Patent number: 6072207
    Abstract: A liquid precursor containing a metal is applied to a substrate, RTP baked, and annealed to form a layered superlattice material. Special polyoxyalkylated precursor solutions are designed to optimize polarizability of the corresponding metal oxide materials by adding dopants including stoichiometric excess amounts of bismuth and tantalum. The RTP baking process is especially beneficial in optimizing the polarizability of the resultant metal oxide.
    Type: Grant
    Filed: March 17, 1995
    Date of Patent: June 6, 2000
    Assignees: Symetrix Corporation, Olympus Optical Co., Ltd.
    Inventors: Hiroyuki Yoshimori, Carlos A. Paz De Araujo, Takeshi Ito, Michael C. Scott, Larry D. McMillan
  • Patent number: 6056994
    Abstract: A precursor liquid comprising several metal 2-ethylhexanoates, such as strontium, tantalum, and bismuth 2-ethylhexanoates, in a xylenes/methyl ethyl ketone solvent is prepared, and deposited on a substrate. In one embodiement the substrate is placed within a vacuum deposition chamber, the precursor liquid is misted, and the mist is flowed into the deposition chamber while maintaining the chamber at ambient temperature to deposit the precursor liquid on the substrate. In another embodiment, the precursor is spin-coated on the substrate. The liquid is dried, baked, and annealed to form a thin film of a layered superlattice material, such as strontium bismuth tantalate, on the substrate.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: May 2, 2000
    Assignee: Symetrix Corporation
    Inventors: Carlos A. Paz de Araujo, Larry D. McMillan, Michael C. Scott, Joseph D. Cuchiaro
  • Patent number: 6051858
    Abstract: A transistor on a silicon substrate is covered by an insulating layer. A conducting plug passes through the insulating layer to the transistor drain. The bottom electrode of a ferroelectric capacitor that directly overlies the plug and drain contacts the plug. The ferroelectric layer is self-patterned and completely overlies the memory cell. A self-patterned sacrificial layer completely overlies the ferroelectric layer. The bottom electrode of the capacitor is completely enclosed by the ferroelectric layer, the insulating layer, and the conducting plug.
    Type: Grant
    Filed: July 15, 1997
    Date of Patent: April 18, 2000
    Assignees: Symetrix Corporation, Mitsubishi Materials Corporation
    Inventors: Hiroto Uchida, Nobuyuki Soyama, Katsumi Ogi, Michael C. Scott, Joseph D. Cuchiaro, Larry D. McMillan, Carlos A. Paz de Araujo
  • Patent number: 6037046
    Abstract: An electromagnetic wave absorption panel for use in building construction includes a protective tile layer, an absorber layer, a metal reflective layer, and a building support layer, such as concrete. The absorber layer is multi-component structure, such as: a high dielectric constant layer and ferrite layer; a ferrite layer and a low dielectric constant layer; a ferrite and a polymer; a polymer and a material having a higher dielectric constant than the polymer; a ferroelectric, a ferrite, and a polymer; a ferrite, a polymer, and a high dielectric constant material; and a high dielectric constant material, a material in which the imaginary part of the permeability is greater than or equal to the real part of the permeability, and a low dielectric constant material. The invention also includes combinations of the above, such as: a high dielectric constant material, a ferrite, and a low dielectric constant material; and multiple layers of a ferrite and a polymer.
    Type: Grant
    Filed: January 13, 1997
    Date of Patent: March 14, 2000
    Assignees: Symetrix Corporation, Fujita Corporation
    Inventors: Vikram Joshi, Kenichi Kimura, Carlos A. Paz de Araujo, Hiroshi Kiyokawa
  • Patent number: 6025619
    Abstract: A method for fabricating an integrated circuit capacitor having a dielectric layer comprising BST with excess A-site and B-site materials such as barium and titanium added. An organometallic or metallic soap precursor solution is prepared comprising a stock solution of BST of greater than 99.999% purity blended with excess A-site and B-site materials such as barium and titanium such that the barium is in the range of 0.01-100 mol %, and such that the titanium is in the range of 0.01-100 mol %. A xylene exchange is then performed to adjust the viscosity of the solution for spin-on application to a substrate. The precursor solution is spun on a first electrode, dried at 400.degree. C. for 2 to 10 minutes, then annealed at 650.degree. C. to 800.degree. C. for about an hour to form a layer of BST with excess titanium. A second electrode is deposited, patterned, and annealed at between 650.degree. C. to 800.degree. C. for about 30 minutes.
    Type: Grant
    Filed: December 2, 1997
    Date of Patent: February 15, 2000
    Inventors: Masamichi Azuma, Carlos A. Paz De Araujo, Michael C. Scott
  • Patent number: 6022669
    Abstract: A first photosensitive liquid solution is applied to a substrate, patterned through exposure to radiation and development, and annealed to form a desired solid material, such as SrBi.sub.2 Ta.sub.2 O.sub.9, that is incorporated into a component of an integrated circuit Fabrication processes are designed protect the self-patterned solid material from conventional IC processing and to protect the conventional materials, such as silicon, from elements in the self-patterned solid material. In one embodiment, a layer of bismuth oxide is formed on the SrBi.sub.2 Ta.sub.2 O.sub.9 and a silicon oxide hole is etched to the bismuth oxide. The bismuth oxide protects the SrBi.sub.2 Ta.sub.2 O.sub.9 from the etchant, and is reduced by the etchant to bismuth. Any remaining bismuth oxide and much of the bismuth are vaporized in the anneal, and the remaining bismuth is incorporated into the SrBi.sub.2 Ta.sub.2 O.sub.9.
    Type: Grant
    Filed: July 26, 1996
    Date of Patent: February 8, 2000
    Assignees: Symetrix Corporation, Mitsubishi Materials Corporation
    Inventors: Hiroto Uchida, Nobuyuki Soyama, Kensuke Kageyama, Katsumi Ogi, Michael C. Scott, Joseph D. Cuchiaro, Gary F. Derbenuick, Larry D. McMillan, Carlos A. Paz de Araujo
  • Patent number: 6017579
    Abstract: A new method (P200) is provided for making magnesium oxide layers (122) in plasma displays (100). A magnesium carboxylate liquid precursor solution is applied to a display panel (102), dried, and annealed to yield a solid magnesium oxide layer (122) having excellent electro-optical performance.
    Type: Grant
    Filed: April 14, 1997
    Date of Patent: January 25, 2000
    Assignees: Symetrix Corporation, Matsushita Electronics Corporation
    Inventors: Gota Kano, Carlos A. Paz De Araujo, Koji Arita, Michael C. Scott, Larry D. McMillan, Shinichiro Hayashi
  • Patent number: 5997642
    Abstract: A mass flow controller controls the delivery of a precursor to a mist generator. The precursor is misted utilizing a venturi in which a combination of oxygen and nitrogen gas is charged by a corona wire and passes over a precursor-filled throat. The mist is electrically filtered so that it comprises predominately negative ions, passes into a velocity reduction chamber, and then flows into a deposition chamber through inlet ports in an inlet plate that is both a partition between the chambers and a grounded electrode. The inlet plate is located above and substantially parallel to the plane of the substrate on which the mist is to be deposited. The substrate is positively charged to a voltage of about 5000 volts. There are 440 inlet ports per square inch in an 39 square inch inlet port area of the inlet plate directly above the substrate. The inlet port area is approximately equal to the substrate area.
    Type: Grant
    Filed: November 17, 1997
    Date of Patent: December 7, 1999
    Assignee: Symetrix Corporation
    Inventors: Narayan Solayappan, Larry D. McMillan, Carlos A. Paz de Araujo
  • Patent number: 5972428
    Abstract: A liquid primer is misted, flowed into a deposition chamber and deposited on a substrate. A liquid precursor is then misted, flowed into a deposition chamber and deposited on the substrate. The primer and precursor are dried to form a solid thin film, which is then annealed to form a part of an electronic component in an integrated circuit, such as the dielectric in a memory cell. The primer is a solvent, and the precursor includes a metal carboxylate, a metal alkoxide, or a metal alkoxycarboxylate in a precursor solvent. Preferably, the primer and the precursor solvent are the same solvent, such as 2-methoxyethanol, xylenes, or n-butyl acetate.
    Type: Grant
    Filed: March 5, 1996
    Date of Patent: October 26, 1999
    Assignees: Symetrix Corporation, Matsushita Electronics Corporation
    Inventors: Shinichiro Hayashi, Larry D. McMillan, Masamichi Azuma, Carlos A. Paz de Araujo
  • Patent number: 5966318
    Abstract: A memory includes a bitline data signal input (24), at least one memory unit (20), a writing circuit (128) which writes a polarization state into each memory unit (20) responsive to the bitline data signal input, and a sensing circuit (130) that senses a polarization state of each memory unit (20). Each memory unit (20) includes a ferroelectric capacitor (22) and a buffer amplifier (26) in electrical series relationship with the ferroelectric capacitor (22) and the bitline data signal input (24). The buffer amplifier (26) capacitively isolates the ferroelectric capacitor (22) from the bitline data signal input (24) so that the ferroelectric capacitor (22) may be made smaller in size than would otherwise be the case.
    Type: Grant
    Filed: December 17, 1996
    Date of Patent: October 12, 1999
    Assignee: Raytheon Company
    Inventors: O. Glenn Ramer, John J. Drab, Larry D. McMillan, Carlos A. Paz de Araujo
  • Patent number: 5965219
    Abstract: UV radiation is applied to a substrate in a deposition chamber to desorb water and other contaminates from it. A liquid precursor is misted, flowed into the deposition chamber and deposited on a substrate while UV radiation is applied to the mist. The film of liquid on the substrate is dried and annealed on the substrate while the UV radiation is applied to form a solid thin film of a metal oxide. The thin film is then incorporated into an electronic device of an integrated circuit fabricated on the substrate. The application of UV radiation to both the mist during deposition and the thin film after deposition significantly increases the quality of the resulting integrated circuits. The process has been found to be particularly excellent for making BST, strontium bismuth tantalate, and strontium bismuth niobate.
    Type: Grant
    Filed: January 25, 1996
    Date of Patent: October 12, 1999
    Assignees: Symetrix Corporation, Matsushita Electronics Corporation
    Inventors: Shinichiro Hayashi, Larry D. McMillan, Carlos A. Paz de Araujo
  • Patent number: 5962085
    Abstract: A substrate is located within a deposition chamber, the substrate defining a substrate plane. A barrier plate is disposed in spaced relation above the substrate and substantially parallel thereto, the area of said barrier plate in a plane parallel to said substrate being substantially equal to said area of said substrate in said substrate plane, i.e. within 10% of said substrate area. The barrier plate has a smoothness tolerance of 5% of the average distance between said barrier plate and said substrate. A mist is generated, allowed to settle in a buffer chamber, filtered through a 1 micron filter, and flowed into the deposition chamber between the substrate and barrier plate to deposit a liquid layer on the substrate. The liquid is dried to form a thin film of solid material on the substrate, which is then incorporated into an electrical component of an integrated circuit.
    Type: Grant
    Filed: March 4, 1996
    Date of Patent: October 5, 1999
    Assignees: Symetrix Corporation, Matsushita Electronics Corporation
    Inventors: Shinichiro Hayashi, Larry D. McMillan, Masamichi Azuma, Carlos A. Paz de Araujo
  • Patent number: 5955754
    Abstract: Metal alkoxycarboxylate-based liquid precursor solutions are used form electronic devices (100) that include mixed layered superlattice materials (112) of a type having discrete oxygen octahedral layers (124) and (128) collated with a superlattice-generator layer (116). The precursor solutions include a plurality of metal moieties in effective amounts for yielding the layered superlattice materials. These metal moieties are mixed to include an A/B portion capable of forming an A/B layer (124), a perovskite-like AB layer portion capable of forming a perovskite-like AB octahedral layer (128), and a superlattice-generator portion capable of forming the superlattice-generator layer (116). The precursors are deposited in liquid form upon a substrate and annealed to provide the layered superlattice materials.
    Type: Grant
    Filed: March 17, 1995
    Date of Patent: September 21, 1999
    Assignees: Symetrix Corporation, Matsushita Electronics Corporation
    Inventors: Masamichi Azuma, Carlos A. Paz De Araujo, Larry D. McMillan
  • Patent number: 5942376
    Abstract: Solution films of a photosensitive metal arylketone alcoholate are micro-patterned by exposure to ultraviolet radiation under a mask. The resultant patterns are developed in an apolar solvent and annealed to provide thin film metal oxides for use in integrated circuits.
    Type: Grant
    Filed: August 14, 1997
    Date of Patent: August 24, 1999
    Assignees: Symetrix Corporation, Mitsubishi Materials Corporation
    Inventors: Hiroto Uchida, Nobuyuki Soyama, Kensuke Kageyama, Katsumi Ogi, Michael C. Scott, Larry D. McMillan, Carlos A. Paz de Araujo